FFKM vs PTFE Seals \u2014 WordPress Page Preview<\/title>\n <style>\nhtml, body { margin: 0; padding: 0; }\n\/* WordPress\u300c\u5916\u89c2 \u2192 \u81ea\u5b9a\u4e49 \u2192 \u989d\u5916 CSS\u300d\uff1a\u590d\u5236\u672c\u6587\u4ef6\u5168\u90e8\u5185\u5bb9\u3002\u5168\u90e8\u89c4\u5219\u4f7f\u7528 fpt \u547d\u540d\u7a7a\u95f4\u3002 *\/\n.fpt-page,\n.fpt-page * { box-sizing: border-box; }\n.fpt-page {\n --ink: #1c2635;\n --muted: #697689;\n --line: #dde3ec;\n --paper: #fff;\n --soft: #f6f8fb;\n --deep: #080d18;\n --deep-2: #111827;\n --purple: #9d72f2;\n --purple-dark: #6643c3;\n --cyan: #51d4da;\n --cyan-dark: #168ba0;\n --amber: #ffca68;\n --coral: #f27d68;\n --shadow: 0 24px 72px rgba(26,34,59,.12);\n position: relative;\n width: 100vw;\n max-width: 100vw;\n margin-left: calc(50% - 50vw);\n overflow: visible;\n color: var(--ink);\n background: var(--paper);\n font-family: Inter,\"Avenir Next\",\"Segoe UI\",Arial,sans-serif;\n font-size: 17px;\n line-height: 1.76;\n text-rendering: 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font-weight: 820; }\n.fpt-selector-stage { position: relative; min-height: 380px; overflow: hidden; border-right: 1px solid rgba(190,202,228,.15); background: radial-gradient(circle at 50% 50%,#273249,#151f33 66%); }\n.fpt-scale { position: absolute; top: 35px; right: 25px; left: 25px; display: grid; grid-template-columns: auto 1fr auto; gap: 9px; align-items: center; }\n.fpt-scale span { color: #8390a6; font-size: 6px; font-weight: 900; letter-spacing: .08em; }\n.fpt-scale i { height: 2px; background: linear-gradient(90deg,var(--purple),var(--cyan)); }\n.fpt-choice { position: absolute; display: grid; place-items: center; width: 96px; height: 96px; border: 2px solid #59677f; border-radius: 50%; opacity: .35; transition: opacity .24s ease,transform .24s ease,box-shadow .24s ease; }\n.fpt-choice b { color: #edf4ff; font-size: 16px; }\n.fpt-choice small { margin-top: -25px; color: #8793a8; font-size: 6px; font-weight: 900; }\n.fpt-choice.is-ffkm { top: 103px; left: 27px; border-color: 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0; color: #645942; font-size: 12px; line-height: 1.62; }\n.fpt-source-note { margin: 27px 0 0 !important; padding: 17px 19px; border-left: 4px solid var(--cyan); border-radius: 0 10px 10px 0; color: #536175 !important; background: #f0f8fa; font-size: 11px; line-height: 1.65; }\n\n.fpt-recovery-stage { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; gap: 19px; align-items: center; padding: 36px 30px; }\n.fpt-recovery-stage > div { min-height: 210px; padding: 20px; border: 1px solid #dce2eb; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-recovery-stage > em { color: #909aaa; font-size: 8px; font-style: normal; font-weight: 900; text-align: center; }\n.fpt-recovery-stage > div > span { color: #684ab7; font-size: 8px; font-weight: 900; letter-spacing: .11em; }\n.fpt-recovery-stage i { display: block; width: 103px; height: 103px; margin: 25px auto; border: 28px solid #7952cd; border-radius: 50%; }\n.fpt-recovery-stage .is-loaded i { height: 72px; margin-top: 40px; margin-bottom: 41px; border-top-width: 18px; border-bottom-width: 18px; }\n.fpt-recovery-stage .is-energized i { box-shadow: inset 18px 0 0 rgba(81,212,218,.45),-13px 0 0 rgba(81,212,218,.22); }\n.fpt-recovery-stage b,\n.fpt-recovery-stage small { display: block; }\n.fpt-recovery-stage b { color: #37445a; font-size: 11px; }\n.fpt-recovery-stage small { margin-top: 5px; color: #838d9d; font-size: 9px; }\n.fpt-chip-grid { display: flex; flex-wrap: wrap; gap: 8px; margin: 29px 0; }\n.fpt-chip-grid span { padding: 8px 12px; border: 1px solid #d8cef0; border-radius: 999px; color: #684ca6; background: #f5f1fc; font-size: 9px; font-weight: 800; }\n.fpt-chip-grid.is-cyan span { border-color: #c9e4e8; color: #28798b; background: #eff9fa; }\n.fpt-evidence-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 12px; margin: 31px 0; }\n.fpt-evidence-grid > div { padding: 22px 20px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-evidence-grid > div > span { color: #684ba8; font-size: 8px; font-weight: 900; letter-spacing: .14em; }\n.fpt-evidence-grid h3 { margin: 11px 0 10px; font-size: 17px; }\n.fpt-evidence-grid p { margin: 0; color: #697587; font-size: 10px; line-height: 1.6; }\n.fpt-evidence-grid .is-dark { border-color: #4e5c73; background: #172137; }\n.fpt-evidence-grid .is-dark > span { color: var(--cyan); }\n.fpt-evidence-grid .is-dark h3 { color: #f2f6ff; }\n.fpt-evidence-grid .is-dark p { color: #acb7c9; }\n\n.fpt-ptfe-stage { position: relative; display: grid; grid-template-columns: 1fr .8fr 1fr; gap: 23px; align-items: center; padding: 42px 35px; }\n.fpt-ptfe-stage > div { position: relative; min-height: 210px; padding: 20px; border: 1px solid #dce3ec; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-ptfe-stage span { color: #24798a; font-size: 8px; font-weight: 900; letter-spacing: .11em; }\n.fpt-ptfe-stage b { display: block; margin-top: 141px; color: #425268; font-size: 10px; }\n.fpt-jacket-left,\n.fpt-jacket-right { position: absolute; top: 64px; width: 38px; height: 77px; border: 2px solid #79d4d9; background: linear-gradient(#dfffff,#6ec8cf); }\n.fpt-jacket-left { right: 36%; border-radius: 6px 16px 16px 6px; }\n.fpt-jacket-right { left: 36%; border-radius: 16px 6px 6px 16px; }\n.fpt-spring-core { background: #172137 !important; }\n.fpt-spring-core span { color: var(--amber); }\n.fpt-spring-core i { position: absolute; top: 82px; right: 25%; left: 25%; height: 45px; background: repeating-linear-gradient(135deg,transparent 0 9px,#ffca68 10px 14px,transparent 15px 23px); }\n.fpt-spring-core b { color: #d8e3f2; }\n.fpt-hardware-top,\n.fpt-hardware-bottom { position: absolute; right: 17%; left: 17%; height: 35px; border-radius: 5px; background: linear-gradient(#bbc9d0,#687984); }\n.fpt-hardware-top { top: 60px; }\n.fpt-hardware-bottom { top: 115px; }\n\n.fpt-mechanism-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-mechanism-compare > div { padding: 25px 24px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-mechanism-compare > div > span { font-size: 9px; font-weight: 900; letter-spacing: .14em; }\n.fpt-mechanism-compare h3 { margin: 10px 0 13px; font-size: 20px; }\n.fpt-mechanism-compare ol { margin: 0 0 20px; padding-left: 21px; }\n.fpt-mechanism-compare li { padding: 5px 0; color: #687487; font-size: 10px; }\n.fpt-mechanism-compare > div > b { display: block; padding: 10px; border-radius: 7px; font-size: 8px; text-align: center; }\n.fpt-mechanism-compare .is-ffkm { border-color: #cfc1ee; background: #f5f1fc; }\n.fpt-mechanism-compare .is-ffkm > span { color: #6f4dc1; }\n.fpt-mechanism-compare .is-ffkm > b { color: #eaddff; background: #51388d; }\n.fpt-mechanism-compare .is-ptfe { border-color: #c8e2e6; background: #f0f9fa; }\n.fpt-mechanism-compare .is-ptfe > span { color: #217b8d; }\n.fpt-mechanism-compare .is-ptfe > b { color: #dffcff; background: #176c7d; }\n\n.fpt-chemical-path { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr auto 1.15fr; gap: 9px; align-items: center; margin: 31px 0; padding: 25px 20px; border: 1px solid #dde3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-chemical-path > div { min-height: 118px; padding: 17px 14px; border: 1px solid #dce2eb; border-radius: 10px; background: #fff; }\n.fpt-chemical-path > i { color: #929cad; font-style: normal; }\n.fpt-chemical-path span,\n.fpt-chemical-path b { display: block; }\n.fpt-chemical-path span { color: #6950a6; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-chemical-path b { margin-top: 15px; color: #48546a; font-size: 10px; line-height: 1.5; }\n.fpt-chemical-path .is-result { border-color: #4b5b72; background: #172137; }\n.fpt-chemical-path .is-result span { color: var(--cyan); }\n.fpt-chemical-path .is-result b { color: #dbe5f3; }\n.fpt-two-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 30px 0; }\n.fpt-two-panel > div { padding: 23px 22px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-two-panel > div > span { color: #247b8d; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-two-panel h3 { margin: 10px 0 12px; font-size: 18px; }\n.fpt-two-panel p { margin: 13px 0 0; font-size: 10px; line-height: 1.58; }\n.fpt-two-panel ul,\n.fpt-material-choice ul,\n.fpt-vacuum-layout ul,\n.fpt-install-grid ul,\n.fpt-choice-card ul,\n.fpt-contact-spec ul { margin: 0; padding: 0; list-style: none; }\n.fpt-two-panel li,\n.fpt-material-choice li,\n.fpt-vacuum-layout li,\n.fpt-install-grid li,\n.fpt-choice-card li,\n.fpt-contact-spec li { position: relative; padding: 4px 0 4px 15px; color: #6a7688; font-size: 10px; line-height: 1.5; }\n.fpt-two-panel li::before,\n.fpt-material-choice li::before,\n.fpt-vacuum-layout li::before,\n.fpt-install-grid li::before,\n.fpt-choice-card li::before,\n.fpt-contact-spec li::before { content: \"\"; position: absolute; top: 11px; left: 1px; width: 5px; height: 5px; border-radius: 50%; background: #58bec5; }\n.fpt-two-panel .is-ffkm { border-color: #cec1ed; background: #f5f1fc; }\n.fpt-two-panel .is-ffkm > span { color: #6b4ab9; }\n.fpt-two-panel .is-ffkm li::before { background: var(--purple); }\n.fpt-data-strip { display: grid; grid-template-columns: repeat(6,1fr); gap: 1px; margin: 28px 0; overflow: hidden; border: 1px solid #4d5a70; border-radius: 10px; background: #4d5a70; }\n.fpt-data-strip span { padding: 16px 8px; color: #cdd6e5; background: #172137; font-size: 8px; font-weight: 900; letter-spacing: .08em; text-align: center; }\n\n.fpt-temperature-stage { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; padding: 38px 35px; }\n.fpt-temperature-stage > div { padding: 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #fff; text-align: center; }\n.fpt-temperature-stage span,\n.fpt-temperature-stage small { display: block; }\n.fpt-temperature-stage span { font-size: 8px; font-weight: 900; letter-spacing: .12em; }\n.fpt-temperature-stage i { position: relative; display: block; width: 80%; height: 18px; margin: 35px auto 30px; border-radius: 999px; background: #e1e5ec; }\n.fpt-temperature-stage i::before { content: \"\"; position: absolute; inset: 0 auto 0 0; width: 75%; border-radius: inherit; }\n.fpt-temperature-stage i b { position: absolute; top: -28px; right: 11%; font-size: 16px; font-style: normal; }\n.fpt-temperature-stage small { color: #7d8899; font-size: 9px; }\n.fpt-temperature-stage .is-ptfe span,\n.fpt-temperature-stage .is-ptfe i b { color: #207b8e; }\n.fpt-temperature-stage .is-ptfe i::before { background: var(--cyan); }\n.fpt-temperature-stage .is-ffkm span,\n.fpt-temperature-stage .is-ffkm i b { color: #6849b7; }\n.fpt-temperature-stage .is-ffkm i::before { width: 92%; background: var(--purple); }\n\n.fpt-cryo-scale { position: relative; display: grid; grid-template-columns: 1.25fr auto 1fr auto 1fr; gap: 12px; align-items: center; margin: 31px 0; padding: 30px 24px 55px; border: 1px solid #dce3ec; border-radius: 14px; background: linear-gradient(90deg,#eafafd,#f3f5fb,#faf5fd); }\n.fpt-cryo-scale > div { min-height: 128px; padding: 20px 16px; border: 1px solid #d9e2ed; border-radius: 11px; background: #fff; }\n.fpt-cryo-scale > i { width: 20px; height: 2px; background: #9aa7b8; }\n.fpt-cryo-scale span,\n.fpt-cryo-scale b,\n.fpt-cryo-scale small { display: block; }\n.fpt-cryo-scale span { color: #54647b; font-size: 16px; font-weight: 900; }\n.fpt-cryo-scale b { margin-top: 12px; color: #3d4d63; font-size: 10px; }\n.fpt-cryo-scale small { margin-top: 5px; color: #7f8b9b; font-size: 8px; }\n.fpt-cryo-scale .is-extreme { border-color: #9adce2; background: #f1fcfd; }\n.fpt-cryo-scale .is-extreme span { color: #147f94; }\n.fpt-cryo-scale .is-special { border-color: #d6cbee; background: #f8f4fd; }\n.fpt-cryo-scale .is-special span { color: #7558b6; }\n.fpt-cryo-scale > em { position: absolute; right: 25px; bottom: 17px; color: #738093; font-size: 8px; font-style: normal; font-weight: 900; letter-spacing: .1em; }\n.fpt-application-chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 28px 0; }\n.fpt-application-chips span { padding: 8px 12px; border: 1px solid #cce4e8; border-radius: 999px; color: #27798a; background: #f0fafb; font-size: 9px; font-weight: 800; }\n\n.fpt-friction-compare { display: grid; grid-template-columns: 1fr auto 1fr; gap: 22px; align-items: center; margin: 31px 0; padding: 33px 28px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-friction-compare > div { padding: 22px; border: 1px solid #dbe2eb; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-friction-compare > em { color: #8c97a8; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-friction-compare span,\n.fpt-friction-compare b,\n.fpt-friction-compare small { display: block; }\n.fpt-friction-compare span { font-size: 9px; font-weight: 900; }\n.fpt-friction-compare i { display: block; width: 82%; height: 18px; margin: 29px auto; border-radius: 999px; }\n.fpt-friction-compare b { color: #425066; font-size: 12px; }\n.fpt-friction-compare small { margin-top: 5px; color: #7e899a; font-size: 9px; }\n.fpt-friction-compare .is-ffkm span { color: #6748b7; }\n.fpt-friction-compare .is-ffkm i { background: repeating-linear-gradient(90deg,#9d72f2 0 13px,#7451c3 14px 22px); }\n.fpt-friction-compare .is-ptfe span { color: #217b8d; }\n.fpt-friction-compare .is-ptfe i { height: 7px; background: linear-gradient(90deg,#9aeeee,var(--cyan)); }\n.fpt-application-grid { display: grid; grid-template-columns: repeat(5,1fr); gap: 8px; margin: 28px 0; }\n.fpt-application-grid > div { display: flex; gap: 10px; align-items: center; min-height: 67px; padding: 13px; border: 1px solid #dce3ec; border-radius: 10px; background: #f8f9fb; }\n.fpt-application-grid i { display: grid; flex: 0 0 28px; place-items: center; width: 28px; height: 28px; border-radius: 50%; color: #21798b; background: #e4f7f8; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-application-grid span { color: #526076; font-size: 9px; font-weight: 730; }\n\n.fpt-motion-map { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; gap: 12px; align-items: center; margin: 31px 0; }\n.fpt-motion-map > div { min-height: 130px; padding: 21px 18px; border: 1px solid #dce3ec; border-radius: 11px; background: #f8f9fb; }\n.fpt-motion-map > i { color: #919cad; font-style: normal; }\n.fpt-motion-map span,\n.fpt-motion-map b,\n.fpt-motion-map small { display: block; }\n.fpt-motion-map span { color: #65738a; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-motion-map b { margin-top: 16px; color: #38465c; font-size: 12px; }\n.fpt-motion-map small { margin-top: 5px; color: #7d889a; font-size: 9px; }\n.fpt-motion-map > div:first-child { border-color: #d1c4ed; background: #f6f2fc; }\n.fpt-motion-map > div:first-child span { color: #6a4bb8; }\n.fpt-motion-map > div:last-child { border-color: #c5e4e7; background: #effafb; }\n.fpt-motion-map > div:last-child span { color: #217c8d; }\n\n.fpt-spring-stage { display: grid; grid-template-columns: 1fr auto 1.08fr auto 1fr; gap: 14px; align-items: center; padding: 36px 31px; }\n.fpt-spring-stage > div { min-height: 195px; padding: 22px 17px; border: 1px solid #dce3ec; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-spring-stage > em { color: #8e99aa; font-style: normal; }\n.fpt-spring-stage span,\n.fpt-spring-stage b,\n.fpt-spring-stage small { display: block; }\n.fpt-spring-stage span { color: #247b8c; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-spring-stage i { display: block; width: 100px; height: 47px; margin: 29px auto; background: repeating-linear-gradient(135deg,transparent 0 10px,#57cfd5 11px 15px,transparent 16px 25px); }\n.fpt-spring-stage i.is-light { opacity: .55; transform: scale(.85); }\n.fpt-spring-stage i.is-heavy { transform: scale(1.13); }\n.fpt-spring-stage b { color: #3e4d63; font-size: 12px; }\n.fpt-spring-stage small { margin-top: 5px; color: #7f8999; font-size: 9px; }\n.fpt-spring-stage .is-center { border-color: #556379; background: #172137; }\n.fpt-spring-stage .is-center span { color: var(--amber); }\n.fpt-spring-stage .is-center b { color: #f0f5ff; }\n.fpt-spring-stage .is-center small { color: #aeb9ca; }\n.fpt-material-choice { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 30px 0; }\n.fpt-material-choice > div { padding: 24px 23px; border: 1px solid #d1c4ed; border-radius: 13px; background: #f6f2fc; }\n.fpt-material-choice > div > span { color: #684ab6; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-material-choice ul { margin-top: 15px; }\n.fpt-material-choice li::before { background: var(--purple); }\n.fpt-material-choice .is-ptfe { border-color: #c3e1e5; background: #effafb; }\n.fpt-material-choice .is-ptfe > span { color: #217b8c; }\n.fpt-material-choice .is-ptfe li::before { background: var(--cyan); }\n\n.fpt-vacuum-layout { display: grid; grid-template-columns: 1fr .7fr 1fr; gap: 13px; align-items: stretch; margin: 31px 0; }\n.fpt-vacuum-layout > div { padding: 23px 21px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-vacuum-layout > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-vacuum-layout h3 { margin: 10px 0 13px; font-size: 17px; }\n.fpt-vacuum-layout .is-ffkm { border-color: #d2c5ed; background: #f6f2fc; }\n.fpt-vacuum-layout .is-ffkm > span { color: #6b4bb9; }\n.fpt-vacuum-layout .is-ffkm li::before { background: var(--purple); }\n.fpt-vacuum-layout .is-ptfe { border-color: #c7e3e6; background: #effafb; }\n.fpt-vacuum-layout .is-ptfe > span { color: #217c8d; }\n.fpt-vacuum-core { display: flex; flex-direction: column; align-items: center; justify-content: center; border-color: #4e5c74 !important; color: #edf5ff; background: #172137 !important; text-align: center; }\n.fpt-vacuum-core span { color: var(--amber); }\n.fpt-vacuum-core i { width: 86px; height: 86px; margin: 20px 0; border: 1px solid #66748b; border-radius: 50%; box-shadow: inset 0 0 0 15px #212e48,inset 0 0 0 16px #78859a; }\n.fpt-vacuum-core b { color: #dce5f3; font-size: 10px; }\n\n.fpt-pressure-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-pressure-compare > div { padding: 24px 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-pressure-compare > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-pressure-compare h3 { margin: 10px 0 8px; font-size: 18px; }\n.fpt-pressure-compare p { margin: 0 0 15px; font-size: 10px; line-height: 1.6; }\n.fpt-pressure-compare b { display: block; padding: 9px; border-radius: 7px; font-size: 8px; letter-spacing: .06em; text-align: center; }\n.fpt-pressure-compare .is-ffkm { border-color: #d1c3ee; background: #f6f2fc; }\n.fpt-pressure-compare .is-ffkm span { color: #6a4ab8; }\n.fpt-pressure-compare .is-ffkm b { color: #eadfff; background: #54398f; }\n.fpt-pressure-compare .is-ptfe { border-color: #c7e3e6; background: #effafb; }\n.fpt-pressure-compare .is-ptfe span { color: #217c8d; }\n.fpt-pressure-compare .is-ptfe b { color: #e2fcff; background: #176c7c; }\n.fpt-gap-stage { display: grid; grid-template-columns: 1.35fr .65fr; min-height: 310px; }\n.fpt-gap-stage > div { position: relative; overflow: hidden; border-right: 1px solid #dce3ec; background: #edf1f5; }\n.fpt-gap-stage > div > span { position: absolute; top: 30px; left: 30px; color: #9b4b3b; font-size: 9px; font-weight: 900; letter-spacing: .1em; }\n.fpt-gap-stage > div > em { position: absolute; top: 142px; left: 28px; color: #bd5e4d; font-size: 28px; font-style: normal; }\n.fpt-metal-top,\n.fpt-metal-bottom { position: absolute; right: 9%; left: 19%; height: 73px; border: 2px solid #85929d; background: linear-gradient(#bdc7ce,#667681); }\n.fpt-metal-top { top: 74px; }\n.fpt-metal-bottom { bottom: 59px; }\n.fpt-primary { position: absolute; z-index: 2; top: 119px; left: 42%; width: 105px; height: 105px; border: 27px solid var(--purple); border-radius: 50%; }\n.fpt-backup { position: absolute; z-index: 3; top: 125px; left: calc(42% + 78px); width: 29px; height: 92px; border-radius: 5px; background: var(--cyan); }\n.fpt-gap-stage > div > b { position: absolute; right: 5%; bottom: 17px; color: #5c697c; font-size: 8px; letter-spacing: .09em; }\n.fpt-gap-stage aside { padding: 36px 26px; background: #fff; }\n.fpt-gap-stage aside span { color: #227b8d; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-gap-stage aside p { margin: 17px 0 0; font-size: 10px; line-height: 1.62; }\n\n.fpt-semiconductor-map { display: grid; grid-template-columns: 1fr auto 1fr; gap: 17px; align-items: center; margin: 31px 0; padding: 27px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-semiconductor-map > div { min-height: 260px; padding: 23px; border: 1px solid #dce3ec; border-radius: 12px; background: #fff; }\n.fpt-semiconductor-map > i { color: #8995a7; font-size: 20px; font-style: normal; }\n.fpt-semiconductor-map span,\n.fpt-semiconductor-map b,\n.fpt-semiconductor-map small { display: block; }\n.fpt-semiconductor-map span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-semiconductor-map b { margin-top: 12px; padding-bottom: 7px; border-bottom: 1px solid #e2e6ed; color: #48556b; font-size: 10px; }\n.fpt-semiconductor-map small { margin-top: 16px; color: #7d8899; font-size: 9px; line-height: 1.5; }\n.fpt-semiconductor-map .is-ffkm { border-color: #d1c4ed; background: #f6f2fc; }\n.fpt-semiconductor-map .is-ffkm span { color: #694ab8; }\n.fpt-semiconductor-map .is-ptfe { border-color: #c6e2e6; background: #effafb; }\n.fpt-semiconductor-map .is-ptfe span { color: #217c8d; }\n\n.fpt-equipment-map { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; gap: 12px; align-items: center; margin: 31px 0; }\n.fpt-equipment-map > div { min-height: 135px; padding: 21px 18px; border: 1px solid #dce3ec; border-radius: 11px; background: #f8f9fb; }\n.fpt-equipment-map > div:nth-child(1) { border-color: #d2c5ed; background: #f6f2fc; }\n.fpt-equipment-map > div:nth-child(3) { border-color: #c8e3e7; background: #effafb; }\n.fpt-equipment-map > div:last-child { border-color: #526077; background: #172137; }\n.fpt-equipment-map > i { color: #909bad; font-style: normal; }\n.fpt-equipment-map span,\n.fpt-equipment-map b,\n.fpt-equipment-map small { display: block; }\n.fpt-equipment-map span { color: #667389; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-equipment-map b { margin-top: 16px; color: #39475e; font-size: 12px; }\n.fpt-equipment-map small { margin-top: 6px; color: #7e899b; font-size: 9px; line-height: 1.45; }\n.fpt-equipment-map > div:last-child span { color: var(--amber); }\n.fpt-equipment-map > div:last-child b { color: #f2f6ff; }\n.fpt-equipment-map > div:last-child small { color: #abb6c8; }\n.fpt-five-inputs { display: grid; grid-template-columns: repeat(5,1fr); gap: 1px; overflow: hidden; margin: 28px 0; border: 1px solid #505e74; border-radius: 10px; background: #505e74; }\n.fpt-five-inputs span { padding: 16px 8px; color: #ccd5e4; background: #172137; font-size: 8px; font-weight: 900; letter-spacing: .08em; text-align: center; }\n\n.fpt-deformation-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 31px 0; }\n.fpt-deformation-compare > div { min-height: 320px; padding: 25px 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; text-align: center; }\n.fpt-deformation-compare > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-deformation-compare i { display: block; width: 125px; height: 125px; margin: 27px auto; }\n.fpt-deformation-compare .is-ffkm { border-color: #d2c5ed; background: #f6f2fc; }\n.fpt-deformation-compare .is-ffkm > span { color: #6b4bb9; }\n.fpt-deformation-compare .is-ffkm i { height: 78px; margin-top: 51px; margin-bottom: 50px; border: 24px solid #805bd0; border-top-width: 16px; border-bottom-width: 16px; border-radius: 46%; }\n.fpt-deformation-compare .is-ptfe { border-color: #c7e3e6; background: #effafb; }\n.fpt-deformation-compare .is-ptfe > span { color: #217c8d; }\n.fpt-deformation-compare .is-ptfe i { border: 26px solid #53cbd1; border-radius: 50% 50% 36% 61%; transform: skewX(10deg); }\n.fpt-deformation-compare h3 { margin: 0 0 8px; font-size: 17px; }\n.fpt-deformation-compare p { margin: 0; font-size: 10px; line-height: 1.58; }\n.fpt-equation { display: flex; flex-wrap: wrap; gap: 9px; align-items: center; justify-content: center; margin: 30px 0; padding: 23px; border-radius: 13px; color: #eaf2ff; background: #172137; }\n.fpt-equation span { color: #9ba9bd; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-equation b { padding: 8px 10px; border: 1px solid #55637a; border-radius: 6px; color: #e4ecf8; font-size: 9px; }\n.fpt-equation i { color: var(--amber); font-size: 8px; font-style: normal; font-weight: 900; }\n\n.fpt-install-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-install-grid > div { padding: 24px 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-install-grid > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-install-grid h3 { margin: 10px 0 13px; font-size: 18px; }\n.fpt-install-grid .is-ffkm { border-color: #d1c4ed; background: #f6f2fc; }\n.fpt-install-grid .is-ffkm > span { color: #6a4ab8; }\n.fpt-install-grid .is-ffkm li::before { background: var(--purple); }\n.fpt-install-grid .is-ptfe { border-color: #c6e3e6; background: #effafb; }\n.fpt-install-grid .is-ptfe > span { color: #217c8d; }\n.fpt-orientation-card { margin: 30px 0; padding: 24px; border: 1px solid #d9d19f; border-radius: 13px; background: #fffbef; }\n.fpt-orientation-card > span { color: #84671f; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-orientation-card > div { display: grid; grid-template-columns: 1fr auto 1.4fr auto 1fr; gap: 10px; align-items: center; margin-top: 18px; }\n.fpt-orientation-card b,\n.fpt-orientation-card em { padding: 12px; border: 1px solid #e5dcb8; border-radius: 8px; color: #62583f; background: #fff; font-size: 8px; font-style: normal; text-align: center; }\n.fpt-orientation-card i { color: #9c8b55; font-style: normal; }\n.fpt-orientation-card p { margin: 15px 0 0; color: #70664d; font-size: 10px; }\n\n.fpt-cost-equation { display: grid; grid-template-columns: repeat(9,auto); gap: 8px; align-items: center; margin: 31px 0; padding: 25px 20px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-cost-equation > div { min-height: 100px; padding: 16px 11px; border: 1px solid #dce2eb; border-radius: 9px; background: #fff; }\n.fpt-cost-equation > i { color: #919cad; font-style: normal; }\n.fpt-cost-equation span,\n.fpt-cost-equation b { display: block; }\n.fpt-cost-equation span { color: #6750a5; font-size: 7px; font-weight: 900; letter-spacing: .08em; }\n.fpt-cost-equation b { margin-top: 13px; color: #536076; font-size: 9px; line-height: 1.45; }\n.fpt-cost-equation > em { grid-column: 1\/-1; padding: 10px; border-radius: 7px; color: #dfe7f5; background: #172137; font-size: 9px; font-style: normal; font-weight: 900; letter-spacing: .1em; text-align: center; }\n\n.fpt-choice-card { display: grid; grid-template-columns: 1.25fr .75fr; gap: 13px; margin: 31px 0; padding: 27px; border: 1px solid #dce3ec; border-radius: 15px; }\n.fpt-choice-card > div { padding: 3px 4px; }\n.fpt-choice-card > div > span,\n.fpt-choice-card aside > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-choice-card h3 { margin: 12px 0 15px; font-size: 22px; }\n.fpt-choice-card aside { padding: 20px; border-radius: 11px; }\n.fpt-choice-card aside b { display: block; margin-top: 10px; padding-bottom: 7px; border-bottom: 1px solid rgba(255,255,255,.12); font-size: 9px; }\n.fpt-choice-card.is-ffkm { border-color: #cfc0ed; background: #f6f2fc; }\n.fpt-choice-card.is-ffkm > div > span { color: #6c4abd; }\n.fpt-choice-card.is-ffkm li::before { background: var(--purple); }\n.fpt-choice-card.is-ffkm aside { color: #e9dfff; background: #51378b; }\n.fpt-choice-card.is-ffkm aside > span { color: #cfb6ff; }\n.fpt-choice-card.is-ptfe { border-color: #c3e3e6; background: #effafb; }\n.fpt-choice-card.is-ptfe > div > span { color: #207c8e; }\n.fpt-choice-card.is-ptfe aside { color: #dffcff; background: #176c7d; }\n.fpt-choice-card.is-ptfe aside > span { color: #9eeef0; }\n\n.fpt-spring-combination { display: grid; grid-template-columns: repeat(9,auto); gap: 8px; align-items: center; margin: 31px 0; padding: 25px 19px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-spring-combination > div { min-height: 85px; padding: 16px 10px; border: 1px solid #dce2eb; border-radius: 9px; background: #fff; }\n.fpt-spring-combination > div > span { color: #526075; font-size: 7px; font-weight: 900; letter-spacing: .07em; }\n.fpt-spring-combination > i { color: #919cad; font-style: normal; }\n.fpt-spring-combination > em { grid-column: 1\/-1; padding: 11px; border-radius: 7px; color: #e0fbff; background: #176c7d; font-size: 9px; font-style: normal; font-weight: 900; letter-spacing: .1em; text-align: center; }\n.fpt-label { display: inline-block; padding: 5px 8px; border-radius: 999px; font-size: 8px; letter-spacing: .04em; }\n.fpt-label.is-ffkm { color: #5e3daa; background: #eee6fc; }\n.fpt-label.is-ptfe { color: #176d7d; background: #e1f6f8; }\n.fpt-label.is-spring { color: #745d1e; background: #fff1c9; }\n\n.fpt-input-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 11px; margin: 31px 0; }\n.fpt-input-grid article { position: relative; min-height: 145px; padding: 23px 22px 20px 69px; border: 1px solid #dce3ec; border-radius: 12px; background: #f8f9fb; }\n.fpt-input-grid article > i { position: absolute; top: 23px; left: 21px; display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%; color: #6043aa; background: #eee8fa; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-input-grid h3 { margin: 0 0 7px; font-size: 17px; }\n.fpt-input-grid p { margin: 0; font-size: 10px; line-height: 1.58; }\n.fpt-input-grid .is-motion { border-color: #4f5e74; background: #172137; }\n.fpt-input-grid .is-motion i { color: #15333a; background: var(--cyan); }\n.fpt-input-grid .is-motion h3 { color: #f2f6ff; }\n.fpt-input-grid .is-motion p { color: #acb7c9; }\n.fpt-inline-cta { display: grid; grid-template-columns: 1fr auto auto; gap: 14px; align-items: center; margin: 27px 0; padding: 19px 22px; border: 1px solid #53647e; border-radius: 11px; color: #eff5ff !important; background: #172137; transition: transform .2s ease,background .2s ease; }\n.fpt-inline-cta:hover { background: #202d49; transform: translateY(-2px); }\n.fpt-inline-cta span { color: #a8eff0; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-inline-cta b { color: #eff5ff; font-size: 12px; }\n.fpt-inline-cta i { color: var(--amber); font-style: normal; }\n\n.fpt-mistake-list { display: grid; gap: 9px; margin: 30px 0; }\n.fpt-mistake-list article { display: grid; grid-template-columns: 48px 1fr; gap: 17px; align-items: center; padding: 17px 20px; border: 1px solid #dce3ec; border-radius: 11px; background: #f8f9fb; }\n.fpt-mistake-list article > span { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 50%; color: #a34d3c; background: #ffede8; font-size: 9px; font-weight: 900; }\n.fpt-mistake-list h3 { margin: 0 0 3px; font-size: 14px; }\n.fpt-mistake-list p { margin: 0; color: #707c8e; font-size: 10px; line-height: 1.5; }\n\n.fpt-summary-section { padding-bottom: 65px; }\n.fpt-summary-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-summary-pair > div { padding: 24px 23px; border: 1px solid #dce3ec; border-radius: 13px; }\n.fpt-summary-pair span,\n.fpt-summary-pair b { display: block; }\n.fpt-summary-pair span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-summary-pair b { margin-top: 12px; padding-bottom: 7px; border-bottom: 1px solid rgba(70,80,105,.12); color: #4c596e; font-size: 10px; }\n.fpt-summary-pair .is-ffkm { background: #f6f2fc; border-color: #d1c4ed; }\n.fpt-summary-pair .is-ffkm span { color: #6949b7; }\n.fpt-summary-pair .is-ptfe { background: #effafb; border-color: #c6e3e6; }\n.fpt-summary-pair .is-ptfe span { color: #217b8d; }\n.fpt-summary-inputs { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; justify-content: center; margin: 31px 0; padding: 25px; border-radius: 14px; background: #172137; }\n.fpt-summary-inputs span { padding: 7px 9px; border: 1px solid #526078; border-radius: 6px; color: #c0cbdb; font-size: 8px; font-weight: 900; }\n.fpt-summary-inputs i { color: #7b899f; font-size: 9px; font-style: normal; }\n.fpt-summary-inputs b { padding: 8px 11px; border-radius: 6px; color: #143039; background: var(--cyan); font-size: 9px; }\n\n.fpt-faq-list { margin: 31px 0; border-top: 1px solid #dce3ec; }\n.fpt-faq-item { border-bottom: 1px solid #dce3ec; }\n.fpt-faq-item > button { display: grid; grid-template-columns: 1fr 24px; gap: 18px; align-items: center; width: 100%; padding: 20px 4px; border: 0; color: #25344d; background: transparent; text-align: left; cursor: pointer; }\n.fpt-faq-item > button span { font-size: 14px; font-weight: 780; }\n.fpt-faq-item > button i { position: relative; width: 20px; height: 20px; border: 1px solid #c2cad9; border-radius: 50%; }\n.fpt-faq-item > button i::before,\n.fpt-faq-item > button i::after { content: \"\"; position: absolute; top: 9px; left: 5px; width: 8px; height: 1px; background: #6648b4; transition: transform .2s ease; }\n.fpt-faq-item > button i::after { transform: rotate(90deg); }\n.fpt-faq-item > button[aria-expanded=\"true\"] i::after { transform: rotate(0); }\n.fpt-faq-answer { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .28s ease; }\n.fpt-faq-answer > p { min-height: 0; margin: 0; overflow: hidden; color: #647084; font-size: 12px; line-height: 1.7; }\n.fpt-faq-item.is-open .fpt-faq-answer { grid-template-rows: 1fr; }\n.fpt-faq-item.is-open .fpt-faq-answer > p { padding: 0 42px 20px 4px; }\n\n.fpt-contact { margin-top: 78px; padding: 54px; border-radius: 20px; color: #eff5ff; background: radial-gradient(circle at 100% 0,rgba(81,212,218,.2),transparent 43%),radial-gradient(circle at 0 100%,rgba(157,114,242,.16),transparent 46%),#151f33; box-shadow: 0 30px 72px rgba(17,28,52,.2); scroll-margin-top: 100px; }\n.fpt-contact-grid { display: grid; grid-template-columns: 1.18fr .82fr; gap: 50px; align-items: center; }\n.fpt-contact .fpt-eyebrow { margin-bottom: 13px; }\n.fpt-contact h2 { margin: 0 0 17px; color: #f5f8ff; font-size: clamp(32px,4vw,50px); line-height: 1.06; letter-spacing: -.04em; }\n.fpt-contact p { margin-bottom: 25px; color: #abb7ca; font-size: 13px; line-height: 1.65; }\n.fpt-button.is-light { color: #122a31 !important; background: linear-gradient(135deg,#acf5f4,var(--cyan)); }\n.fpt-button.is-light i { margin-left: 12px; font-style: normal; }\n.fpt-contact-spec { padding: 24px; border: 1px solid #53627a; border-radius: 13px; background: rgba(255,255,255,.035); }\n.fpt-contact-spec > span { color: var(--amber); font-size: 8px; font-weight: 900; letter-spacing: .14em; }\n.fpt-contact-spec li { color: #bdc8d9; }\n.fpt-contact-spec li::before { background: var(--cyan); }\n.fpt-back-top { position: fixed; z-index: 80; right: 24px; bottom: 24px; display: grid; place-items: center; width: 44px; height: 44px; border: 1px solid #56657d; border-radius: 50%; color: #eff5ff; background: #172137; box-shadow: 0 12px 30px rgba(16,27,52,.22); opacity: 0; visibility: hidden; transform: translateY(12px); cursor: pointer; transition: opacity .2s ease,visibility .2s ease,transform .2s ease,background .2s ease; }\n.fpt-back-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0); }\n.fpt-back-top:hover { background: #22304d; }\n\n@media (max-width: 1180px) {\n .fpt-hero-inner { grid-template-columns: 1fr .86fr; width: min(1120px,calc(100% - 48px)); }\n .fpt-hero h1 { font-size: clamp(42px,5vw,64px); }\n .fpt-content-shell { grid-template-columns: 250px minmax(0,1fr); gap: 50px; width: min(1100px,calc(100% - 48px)); }\n .fpt-selector-body { grid-template-columns: .62fr .95fr 1.05fr; }\n}\n\n@media (max-width: 900px) {\n .fpt-hero { min-height: auto; }\n .fpt-hero-inner { grid-template-columns: 1fr; min-height: auto; padding: 78px 0 70px; }\n .fpt-hero-copy { max-width: 790px; }\n .fpt-hero-visual { width: min(100%,650px); justify-self: center; }\n .fpt-content-shell { display: block; width: min(790px,calc(100% - 40px)); padding-top: 42px; }\n .fpt-sidebar { margin-bottom: 36px; }\n .fpt-sidebar-card,\n .fpt-sidebar-card.is-fixed,\n .fpt-sidebar-card.is-bottom { position: relative; top: auto; right: auto; bottom: auto; left: auto; width: 100%; max-height: none; }\n .fpt-sidebar-title > span { display: none; }\n .fpt-sidebar-title button { display: flex; width: 100%; align-items: center; justify-content: space-between; }\n .fpt-toc { display: none; max-height: 55vh; }\n .fpt-sidebar-card.is-open .fpt-toc { display: block; }\n .fpt-sidebar-note { display: none; }\n .fpt-selector-body { grid-template-columns: 1fr 1.15fr; }\n .fpt-selector-controls { grid-column: span 2; display: grid; grid-template-columns: repeat(6,1fr); border-right: 0; border-bottom: 1px solid rgba(190,202,228,.15); }\n .fpt-selector-controls button { grid-template-columns: 1fr; text-align: center; }\n .fpt-selector-controls button i { display: none; }\n .fpt-data-strip { grid-template-columns: repeat(3,1fr); }\n .fpt-cost-equation { grid-template-columns: repeat(3,1fr); }\n .fpt-cost-equation > i { display: none; }\n .fpt-cost-equation > em { grid-column: span 3; }\n .fpt-contact { padding: 42px; }\n .fpt-contact-grid { grid-template-columns: 1fr; gap: 30px; }\n}\n\n@media (max-width: 680px) {\n .fpt-page { font-size: 16px; }\n .fpt-hero-inner { width: calc(100% - 32px); padding: 62px 0 55px; }\n .fpt-breadcrumb { margin-bottom: 23px; }\n .fpt-hero h1 { font-size: clamp(37px,12vw,51px); }\n .fpt-hero-deck { font-size: 16px; }\n .fpt-hero-actions { flex-direction: column; }\n .fpt-button { width: 100%; }\n .fpt-metrics div { padding-right: 10px; }\n .fpt-metrics div + div { padding-left: 10px; }\n .fpt-metrics strong { font-size: 21px; }\n .fpt-visual-label { top: 5px; left: 7px; }\n .fpt-hero-visual figcaption { margin-top: 0; text-align: center; }\n .fpt-content-shell { width: calc(100% - 28px); padding-bottom: 75px; }\n .fpt-section { padding-top: 58px; }\n .fpt-section-heading { grid-template-columns: 40px 1fr; gap: 13px; }\n .fpt-section-index { width: 40px; height: 40px; }\n .fpt-section h2 { font-size: 31px; }\n .fpt-intro > p:first-of-type { font-size: 18px; }\n .fpt-article blockquote { padding: 21px 20px 21px 26px; }\n .fpt-article blockquote p { font-size: 16px; }\n .fpt-principle-chain,\n .fpt-evidence-grid,\n .fpt-mechanism-compare,\n .fpt-two-panel,\n .fpt-temperature-stage,\n .fpt-material-choice,\n .fpt-pressure-compare,\n .fpt-semiconductor-map,\n .fpt-deformation-compare,\n .fpt-install-grid,\n .fpt-choice-card,\n .fpt-input-grid,\n .fpt-summary-pair,\n .fpt-contact-grid { grid-template-columns: 1fr; }\n .fpt-selector-head { align-items: flex-start; flex-direction: column; }\n .fpt-selector-body { display: block; }\n .fpt-selector-controls { display: grid; grid-template-columns: repeat(2,1fr); }\n .fpt-selector-stage { min-height: 350px; border-right: 0; border-bottom: 1px solid rgba(190,202,228,.15); }\n .fpt-selector-result { min-height: 300px; }\n .fpt-visual-head { align-items: flex-start; flex-direction: column; gap: 5px; }\n .fpt-visual-head strong { text-align: left; }\n .fpt-recovery-stage,\n .fpt-spring-stage { grid-template-columns: 1fr; padding: 24px 19px; }\n .fpt-recovery-stage > em,\n .fpt-spring-stage > em { transform: rotate(90deg); }\n .fpt-ptfe-stage { grid-template-columns: 1fr; padding: 24px 19px; }\n .fpt-chemical-path,\n .fpt-motion-map,\n .fpt-equipment-map { grid-template-columns: 1fr; }\n .fpt-chemical-path > i,\n .fpt-motion-map > i,\n .fpt-equipment-map > i { text-align: center; transform: rotate(90deg); }\n .fpt-data-strip,\n .fpt-five-inputs { grid-template-columns: 1fr; }\n .fpt-cryo-scale { grid-template-columns: 1fr; padding-bottom: 55px; }\n .fpt-cryo-scale > i { width: 2px; height: 18px; margin: 0 auto; }\n .fpt-friction-compare { grid-template-columns: 1fr; }\n .fpt-friction-compare > em { text-align: center; transform: rotate(90deg); }\n .fpt-application-grid { grid-template-columns: repeat(2,1fr); }\n .fpt-vacuum-layout { grid-template-columns: 1fr; }\n .fpt-gap-stage { grid-template-columns: 1fr; }\n .fpt-gap-stage > div { min-height: 300px; border-right: 0; border-bottom: 1px solid #dce3ec; }\n .fpt-semiconductor-map > i { text-align: center; }\n .fpt-orientation-card > div { grid-template-columns: 1fr; }\n .fpt-orientation-card i { text-align: center; transform: rotate(90deg); }\n .fpt-cost-equation,\n .fpt-spring-combination { grid-template-columns: 1fr; }\n .fpt-cost-equation > em,\n .fpt-spring-combination > em { grid-column: auto; }\n .fpt-spring-combination > i { text-align: center; }\n .fpt-inline-cta { grid-template-columns: 1fr auto; }\n .fpt-inline-cta span { grid-column: span 2; }\n .fpt-contact { margin-top: 55px; padding: 30px 23px; border-radius: 16px; }\n .fpt-contact h2 { font-size: 35px; }\n .fpt-back-top { right: 15px; bottom: 15px; }\n}\n\n@media (prefers-reduced-motion: reduce) {\n .fpt-page *,\n .fpt-page *::before,\n .fpt-page *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }\n}\n <\/style>\n<\/head>\n<body>\n<div class=\"fpt-page\" id=\"fpt-top\" data-fpt-page>\n <div class=\"fpt-reading-progress\" aria-hidden=\"true\"><span data-fpt-progress><\/span><\/div>\n\n <header class=\"fpt-hero\">\n <div class=\"fpt-hero-grid\" aria-hidden=\"true\"><\/div>\n <div class=\"fpt-hero-glow fpt-glow-one\" aria-hidden=\"true\"><\/div>\n <div class=\"fpt-hero-glow fpt-glow-two\" aria-hidden=\"true\"><\/div>\n <div class=\"fpt-hero-inner\">\n <div class=\"fpt-hero-copy\">\n <div class=\"fpt-breadcrumb\"><span>Walle Seals<\/span><i><\/i><span>Materials & Compatibility<\/span><\/div>\n <div class=\"fpt-eyebrow\"><b><\/b>ELASTOMER vs FLUOROPOLYMER<\/div>\n <h1>FFKM vs PTFE Seals: Which Material Is Right for Your Application?<\/h1>\n <p class=\"fpt-hero-deck\">Compare how elasticity, creep, friction, temperature, pressure, vacuum and motion change the correct choice between an FFKM O-ring and an engineered PTFE seal.<\/p>\n <div class=\"fpt-hero-actions\">\n <a class=\"fpt-button fpt-button-primary\" href=\"#fpt-overview\">Compare the materials <b>\u2193<\/b><\/a>\n <a class=\"fpt-button fpt-button-ghost\" href=\"#fpt-selection\">Open the selection guide<\/a>\n <\/div>\n <div class=\"fpt-metrics\" aria-label=\"Guide overview\"><div><strong>2<\/strong><span>material behaviors<\/span><\/div><div><strong>6<\/strong><span>service scenarios<\/span><\/div><div><strong>12<\/strong><span>selection rows<\/span><\/div><\/div>\n <\/div>\n\n <figure class=\"fpt-hero-visual\" aria-label=\"FFKM O-ring and spring energized PTFE seal comparison\">\n <div class=\"fpt-visual-label\"><span>SEALING FORCE<\/span><b>RECOVERY vs ENERGIZATION<\/b><\/div>\n <svg viewBox=\"0 0 720 620\" role=\"img\" aria-labelledby=\"fpt-hero-title fpt-hero-desc\">\n <title id=\"fpt-hero-title\">FFKM and PTFE sealing mechanisms<\/title>\n <desc id=\"fpt-hero-desc\">A split technical illustration comparing an elastomeric FFKM O-ring with a spring energized PTFE lip seal.<\/desc>\n <defs>\n <linearGradient id=\"fpt-ffkm-gradient\" x1=\"0\" y1=\"0\" x2=\"1\" y2=\"1\"><stop offset=\"0\" stop-color=\"#c899ff\"\/><stop offset=\".55\" stop-color=\"#7651ce\"\/><stop offset=\"1\" stop-color=\"#392270\"\/><\/linearGradient>\n <linearGradient id=\"fpt-ptfe-gradient\" x1=\"0\" y1=\"0\" x2=\"1\" y2=\"1\"><stop offset=\"0\" stop-color=\"#efffff\"\/><stop offset=\".45\" stop-color=\"#8fe8ea\"\/><stop offset=\"1\" stop-color=\"#278da0\"\/><\/linearGradient>\n <linearGradient id=\"fpt-metal-gradient\" x1=\"0\" y1=\"0\" x2=\"0\" y2=\"1\"><stop offset=\"0\" stop-color=\"#abc0ca\"\/><stop offset=\"1\" stop-color=\"#465b66\"\/><\/linearGradient>\n <filter id=\"fpt-shadow\" x=\"-40%\" y=\"-40%\" width=\"180%\" height=\"180%\"><feDropShadow dx=\"0\" dy=\"20\" stdDeviation=\"20\" flood-color=\"#000\" flood-opacity=\".4\"\/><\/filter>\n <filter id=\"fpt-glow\" x=\"-180%\" y=\"-180%\" width=\"360%\" height=\"360%\"><feGaussianBlur stdDeviation=\"5\" result=\"b\"\/><feMerge><feMergeNode in=\"b\"\/><feMergeNode in=\"SourceGraphic\"\/><\/feMerge><\/filter>\n <\/defs>\n <g opacity=\".26\" stroke=\"#52657a\" fill=\"none\"><path d=\"M48 118H672M48 208H672M48 298H672M48 388H672M48 478H672\" stroke-dasharray=\"3 11\"\/><path d=\"M105 70V545M225 70V545M345 70V545M465 70V545M585 70V545\" stroke-dasharray=\"3 11\"\/><\/g>\n <path d=\"M360 78V540\" stroke=\"#526478\" stroke-dasharray=\"4 9\" opacity=\".55\"\/>\n <g filter=\"url(#fpt-shadow)\">\n <rect x=\"66\" y=\"196\" width=\"254\" height=\"238\" rx=\"23\" fill=\"#17202d\" stroke=\"#65738a\"\/>\n <rect x=\"400\" y=\"196\" width=\"254\" height=\"238\" rx=\"23\" fill=\"#14242c\" stroke=\"#527b85\"\/>\n <rect x=\"93\" y=\"226\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <rect x=\"93\" y=\"355\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <ellipse cx=\"193\" cy=\"315\" rx=\"74\" ry=\"74\" fill=\"none\" stroke=\"url(#fpt-ffkm-gradient)\" stroke-width=\"39\"\/>\n <rect x=\"427\" y=\"226\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <rect x=\"427\" y=\"355\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <path d=\"M463 275h43v67c0 16-13 29-29 29h-14zM591 275h-43v67c0 16 13 29 29 29h14z\" fill=\"url(#fpt-ptfe-gradient)\" stroke=\"#dffcff\"\/>\n <path d=\"M506 317l11-17 10 17 11-17 10 17\" fill=\"none\" stroke=\"#ffcb68\" stroke-width=\"8\" stroke-linejoin=\"round\" filter=\"url(#fpt-glow)\"\/>\n <\/g>\n <g font-family=\"Arial, sans-serif\"><text x=\"193\" y=\"161\" fill=\"#d9bdff\" text-anchor=\"middle\" font-size=\"13\" font-weight=\"700\">FFKM O-RING<\/text><text x=\"193\" y=\"179\" fill=\"#8492a4\" text-anchor=\"middle\" font-size=\"9\">natural elastic recovery<\/text><text x=\"527\" y=\"161\" fill=\"#a9f5f4\" text-anchor=\"middle\" font-size=\"13\" font-weight=\"700\">PTFE LIP SEAL<\/text><text x=\"527\" y=\"179\" fill=\"#8492a4\" text-anchor=\"middle\" font-size=\"9\">spring + geometry<\/text><path d=\"M193 292v-52\" stroke=\"#c498ff\" stroke-width=\"3\"\/><path d=\"M193 338v52\" stroke=\"#c498ff\" stroke-width=\"3\"\/><path d=\"M471 305l-26-31M583 305l26-31\" stroke=\"#7ce4e6\" stroke-width=\"3\"\/><text x=\"193\" y=\"483\" fill=\"#c7a7f5\" text-anchor=\"middle\" font-size=\"10\" font-weight=\"700\">SQUEEZE \u2192 RECOVERY<\/text><text x=\"527\" y=\"483\" fill=\"#87e4e5\" text-anchor=\"middle\" font-size=\"10\" font-weight=\"700\">SPRING \u2192 LIP CONTACT<\/text><\/g>\n <g transform=\"translate(240 520)\"><rect width=\"240\" height=\"48\" rx=\"10\" fill=\"#0a111b\" stroke=\"#566477\"\/><text x=\"120\" y=\"20\" fill=\"#8291a2\" text-anchor=\"middle\" font-family=\"Arial\" font-size=\"8\" letter-spacing=\"1.4\">SAME CHEMICAL RESISTANCE CLASS<\/text><text x=\"120\" y=\"36\" fill=\"#eff8ff\" text-anchor=\"middle\" font-family=\"Arial\" font-size=\"12\" font-weight=\"700\">DIFFERENT MECHANICAL BEHAVIOR<\/text><\/g>\n <\/svg>\n <figcaption><span><\/span>The sealing mechanism\u2014not only the material name\u2014drives the design.<\/figcaption>\n <\/figure>\n <\/div>\n <\/header>\n\n <div class=\"fpt-content-shell\" data-fpt-shell>\n <aside class=\"fpt-sidebar\" data-fpt-sidebar>\n <div class=\"fpt-sidebar-card\" data-fpt-sidebar-card>\n <div class=\"fpt-sidebar-title\"><span>On this page<\/span><button type=\"button\" data-fpt-toc-toggle aria-expanded=\"false\">Contents <b>+<\/b><\/button><\/div>\n <nav class=\"fpt-toc\" data-fpt-toc aria-label=\"Article contents\">\n <a href=\"#fpt-overview\"><span>00<\/span><em>At a Glance<\/em><\/a>\n <a href=\"#fpt-ffkm\"><span>01<\/span><em>What Is FFKM?<\/em><\/a>\n <a href=\"#fpt-ptfe\"><span>02<\/span><em>What Is PTFE?<\/em><\/a>\n <a href=\"#fpt-elasticity\"><span>03<\/span><em>Fundamental Difference<\/em><\/a>\n <a href=\"#fpt-chemical\"><span>04<\/span><em>Chemical Resistance<\/em><\/a>\n <a href=\"#fpt-high-temp\"><span>05<\/span><em>High Temperature<\/em><\/a>\n <a href=\"#fpt-low-temp\"><span>06<\/span><em>Low Temperature<\/em><\/a>\n <a href=\"#fpt-friction\"><span>07<\/span><em>Friction<\/em><\/a>\n <a href=\"#fpt-dynamic\"><span>08<\/span><em>Dynamic Sealing<\/em><\/a>\n <a href=\"#fpt-spring\"><span>09<\/span><em>Spring Energized PTFE<\/em><\/a>\n <a href=\"#fpt-vacuum\"><span>10<\/span><em>Vacuum Applications<\/em><\/a>\n <a href=\"#fpt-pressure\"><span>11<\/span><em>Pressure & Extrusion<\/em><\/a>\n <a href=\"#fpt-semiconductor\"><span>12<\/span><em>Semiconductor Equipment<\/em><\/a>\n <a href=\"#fpt-pumps\"><span>13<\/span><em>Chemical Pumps & Valves<\/em><\/a>\n <a href=\"#fpt-deformation\"><span>14<\/span><em>Compression Set vs Creep<\/em><\/a>\n <a href=\"#fpt-installation\"><span>15<\/span><em>Installation Differences<\/em><\/a>\n <a href=\"#fpt-cost\"><span>16<\/span><em>Total Cost<\/em><\/a>\n <a href=\"#fpt-choose-ffkm\"><span>17<\/span><em>Choose FFKM<\/em><\/a>\n <a href=\"#fpt-choose-ptfe\"><span>18<\/span><em>Choose PTFE<\/em><\/a>\n <a href=\"#fpt-choose-spring\"><span>19<\/span><em>Choose Spring Energized<\/em><\/a>\n <a href=\"#fpt-selection\"><span>20<\/span><em>Practical Selection Table<\/em><\/a>\n <a href=\"#fpt-information\"><span>21<\/span><em>Information Required<\/em><\/a>\n <a href=\"#fpt-mistakes\"><span>22<\/span><em>Selection Mistakes<\/em><\/a>\n <a href=\"#fpt-summary\"><span>23<\/span><em>Engineering Summary<\/em><\/a>\n <a href=\"#fpt-faq\"><span>24<\/span><em>Frequently Asked Questions<\/em><\/a>\n <a href=\"#fpt-contact\"><span>25<\/span><em>Custom Seal Review<\/em><\/a>\n <\/nav>\n <div class=\"fpt-sidebar-note\"><span>CORE DIFFERENCE<\/span><p>FFKM supplies elastic recovery. PTFE supplies low friction and chemical inertness, often with engineered energization.<\/p><\/div>\n <\/div>\n <\/aside>\n\n <main class=\"fpt-main\">\n <article class=\"fpt-article\" data-fpt-article>\n <section class=\"fpt-intro\">\n <div class=\"fpt-tags\"><span>FFKM Seals<\/span><span>PTFE Seals<\/span><span>Spring Energized<\/span><span>Material Selection<\/span><\/div>\n <p>FFKM and PTFE are both highly fluorinated materials used with aggressive chemicals, high temperatures, vacuum, semiconductor processes, pharmaceutical equipment, pumps, valves and aerospace systems.<\/p>\n <p>The similarity ends at chemical resistance. FFKM is a perfluoroelastomer with rubber-like recovery. PTFE is a fluoropolymer with extremely low friction, limited natural elasticity and a tendency to creep under sustained load.<\/p>\n <blockquote><p><strong>Choose FFKM for elastomeric recovery and conventional O-ring sealing. Choose PTFE when low friction, dry running, cryogenic capability or engineered dynamic performance matters more.<\/strong><\/p><\/blockquote>\n <div class=\"fpt-principle-chain\"><div><span>FFKM<\/span><b>Squeeze<\/b><small>Elastic recovery<\/small><\/div><i>vs<\/i><div><span>PTFE<\/span><b>Lip geometry<\/b><small>Spring or pressure load<\/small><\/div><i>\u2192<\/i><div class=\"is-result\"><span>DECISION<\/span><b>Match the mechanism<\/b><small>Chemistry + motion + temperature<\/small><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-overview\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">00<\/span><div><p>FAST COMPARISON<\/p><h2>FFKM vs PTFE at a Glance<\/h2><\/div><\/div>\n <p>Use the interactive screen to identify the design direction, then verify the exact compound, hardware and duty cycle.<\/p>\n <div class=\"fpt-selector is-static\" data-fpt-selector>\n <div class=\"fpt-selector-head\"><div><span>APPLICATION SCREENING TOOL<\/span><h3>Select the dominant requirement<\/h3><\/div><strong data-fpt-selector-status>Static extreme-chemical seal<\/strong><\/div>\n <div class=\"fpt-selector-body\">\n <div class=\"fpt-selector-controls\" role=\"group\" aria-label=\"Seal application requirements\">\n <button class=\"is-active\" type=\"button\" data-fpt-case=\"static\" aria-pressed=\"true\"><i>01<\/i><span>Static \/ O-ring<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"recip\" aria-pressed=\"false\"><i>02<\/i><span>Reciprocating<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"rotary\" aria-pressed=\"false\"><i>03<\/i><span>Rotary<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"cryo\" aria-pressed=\"false\"><i>04<\/i><span>Cryogenic<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"vacuum\" aria-pressed=\"false\"><i>05<\/i><span>Vacuum<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"heat\" aria-pressed=\"false\"><i>06<\/i><span>Extreme heat<\/span><\/button>\n <\/div>\n <div class=\"fpt-selector-stage\" aria-hidden=\"true\"><div class=\"fpt-scale\"><span>ELASTIC RECOVERY<\/span><i><\/i><span>LOW FRICTION<\/span><\/div><div class=\"fpt-choice is-ffkm\"><b>FFKM<\/b><small>ELASTOMER<\/small><\/div><div class=\"fpt-choice is-ptfe\"><b>PTFE<\/b><small>FLUOROPOLYMER<\/small><\/div><div class=\"fpt-choice is-spring\"><b>SPRING<\/b><small>ENERGIZED PTFE<\/small><\/div><\/div>\n <div class=\"fpt-selector-result\" aria-live=\"polite\"><span data-fpt-result-kicker>USUALLY CONSIDER FIRST: FFKM<\/span><h3 data-fpt-result-title>Use natural recovery in a conventional O-ring gland.<\/h3><p data-fpt-result-copy>For static sealing with aggressive chemistry and high temperature, FFKM provides contact force without a separate energizer.<\/p><div><b>VERIFY<\/b><p data-fpt-result-check>Exact chemistry \u00b7 temperature \u00b7 compression set \u00b7 groove fill<\/p><\/div><a href=\"#fpt-choose-ffkm\" data-fpt-result-link>Open the FFKM decision section \u2192<\/a><\/div>\n <\/div>\n <p class=\"fpt-tool-note\">Initial screening only. Final design depends on the exact compound, seal profile, gland, counterface and operating cycle.<\/p>\n <\/div>\n <div class=\"fpt-table-wrap\" role=\"region\" aria-label=\"FFKM and PTFE overview\" tabindex=\"0\"><table><thead><tr><th>Property<\/th><th>FFKM<\/th><th>PTFE<\/th><\/tr><\/thead><tbody>\n <tr><td>Material family<\/td><td>Perfluoroelastomer<\/td><td>Fluoropolymer<\/td><\/tr><tr><td>Material behavior<\/td><td>Elastic \/ rubber-like<\/td><td>Plastic \/ non-elastomeric<\/td><\/tr><tr><td>Chemical resistance<\/td><td>Exceptional<\/td><td>Exceptional<\/td><\/tr><tr><td>Natural elastic recovery<\/td><td>Excellent<\/td><td>Limited<\/td><\/tr><tr><td>Friction<\/td><td>Moderate<\/td><td>Extremely low<\/td><\/tr><tr><td>Standard O-ring sealing<\/td><td>Excellent<\/td><td>Specialized<\/td><\/tr><tr><td>Dynamic sealing<\/td><td>Application-dependent<\/td><td>Excellent with correct design<\/td><\/tr><tr><td>Dry running<\/td><td>Limited by design<\/td><td>Excellent<\/td><\/tr><tr><td>Long-load concern<\/td><td>Compression set<\/td><td>Creep \/ deformation<\/td><\/tr><tr><td>Cryogenic capability<\/td><td>Compound-dependent<\/td><td>Excellent with correct design<\/td><\/tr><tr><td>Typical products<\/td><td>O-rings, gaskets, molded parts<\/td><td>Lip seals, energized seals, backups, gaskets<\/td><\/tr><tr><td>Energizer<\/td><td>Normally unnecessary<\/td><td>Common in demanding service<\/td><\/tr>\n <\/tbody><\/table><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-ffkm\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">01<\/span><div><p>PERFLUOROELASTOMER<\/p><h2>What Is FFKM?<\/h2><\/div><\/div>\n <p>FFKM is the ASTM designation for perfluoroelastomers engineered to combine rubber-like elasticity, broad chemical resistance and high-temperature stability.<\/p>\n <figure class=\"fpt-visual fpt-ffkm-visual\"><div class=\"fpt-visual-head\"><span>ELASTOMERIC FORCE<\/span><strong>Compression creates recoverable contact pressure<\/strong><\/div><div class=\"fpt-recovery-stage\"><div><span>FREE STATE<\/span><i><\/i><b>Original cross-section<\/b><\/div><em>COMPRESS<\/em><div class=\"is-loaded\"><span>INSTALLED<\/span><i><\/i><b>Recovery pushes outward<\/b><\/div><em>PRESSURE<\/em><div class=\"is-energized\"><span>IN SERVICE<\/span><i><\/i><b>System pressure adds load<\/b><\/div><\/div><figcaption>An FFKM O-ring normally needs no separate metallic spring.<\/figcaption><\/figure>\n <div class=\"fpt-chip-grid\"><span>O-rings<\/span><span>Gaskets<\/span><span>Valve seals<\/span><span>Mechanical seal secondary seals<\/span><span>Custom molded seals<\/span><span>Bonded components<\/span><\/div>\n <div class=\"fpt-evidence-grid\"><div><span>CHEMISTRY<\/span><h3>Grade-specific<\/h3><p>General service, acids, amines, steam and plasma can require different formulations.<\/p><\/div><div><span>PURITY<\/span><h3>Process-specific<\/h3><p>Semiconductor grades may target particles, outgassing and metal-ion contamination.<\/p><\/div><div class=\"is-dark\"><span>MECHANICS<\/span><h3>Elastic sealing<\/h3><p>Recovery, squeeze, compression set and extrusion resistance define performance.<\/p><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-ptfe\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">02<\/span><div><p>FLUOROPOLYMER<\/p><h2>What Is PTFE?<\/h2><\/div><\/div>\n <p>PTFE is a fluoropolymer with exceptional chemical resistance, extremely low friction, wide temperature capability, non-stick behavior and strong dry-running performance. It does not recover like rubber.<\/p>\n <figure class=\"fpt-visual fpt-ptfe-visual\"><div class=\"fpt-visual-head\"><span>ENGINEERED CONTACT<\/span><strong>Geometry and energization compensate for limited elastic memory<\/strong><\/div><div class=\"fpt-ptfe-stage\"><div><span>PTFE JACKET<\/span><i class=\"fpt-jacket-left\"><\/i><i class=\"fpt-jacket-right\"><\/i><b>Low-friction sealing lips<\/b><\/div><div class=\"fpt-spring-core\"><span>METAL SPRING<\/span><i><\/i><b>Continuous outward force<\/b><\/div><div><span>HARDWARE<\/span><i class=\"fpt-hardware-top\"><\/i><i class=\"fpt-hardware-bottom\"><\/i><b>Controlled mating surfaces<\/b><\/div><\/div><figcaption>PTFE seals may also use an elastomer energizer, specialized lip geometry or pressure energization.<\/figcaption><\/figure>\n <div class=\"fpt-chip-grid is-cyan\"><span>Spring energized seals<\/span><span>Rotary seals<\/span><span>Piston seals<\/span><span>Rod seals<\/span><span>Valve seats<\/span><span>Backup rings<\/span><span>Gaskets<\/span><span>PTFE O-rings<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-elasticity\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">03<\/span><div><p>HOW CONTACT FORCE IS CREATED<\/p><h2>The Fundamental Difference: Elasticity<\/h2><\/div><\/div>\n <div class=\"fpt-mechanism-compare\"><div class=\"is-ffkm\"><span>FFKM<\/span><h3>Elastic memory<\/h3><ol><li>Seal is compressed<\/li><li>Elastomer tries to recover<\/li><li>Contact pressure forms<\/li><li>System pressure adds energization<\/li><\/ol><b>NO EXTRA SPRING NORMALLY REQUIRED<\/b><\/div><div class=\"is-ptfe\"><span>PTFE<\/span><h3>Engineered energization<\/h3><ol><li>Jacket or lip is installed<\/li><li>Spring or pressure supplies load<\/li><li>Lips contact the hardware<\/li><li>Geometry manages wear and leakage<\/li><\/ol><b>ENERGIZER COMMON IN DEMANDING DUTY<\/b><\/div><\/div>\n <blockquote><p>FFKM design centers on elastic recovery and compression set. PTFE design centers on creep, lip geometry and how sealing force is maintained.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-chemical\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">04<\/span><div><p>BASE POLYMER \u2260 COMPLETE COMPOUND<\/p><h2>FFKM vs PTFE Chemical Resistance<\/h2><\/div><\/div>\n <p>Both materials cover an exceptionally broad chemical range, so the correct question is not simply \u201cwhich is more resistant?\u201d It is whether the exact FFKM formulation or PTFE compound is compatible with the complete service mixture.<\/p>\n <div class=\"fpt-chemical-path\"><div><span>BASE MATERIAL<\/span><b>FFKM or virgin PTFE<\/b><\/div><i>+<\/i><div><span>FORMULATION<\/span><b>Cure system or fillers<\/b><\/div><i>+<\/i><div><span>ENVIRONMENT<\/span><b>Chemistry + heat + time<\/b><\/div><i>\u2192<\/i><div class=\"is-result\"><span>ACTUAL RESULT<\/span><b>Volume, strength, wear and life<\/b><\/div><\/div>\n <div class=\"fpt-two-panel\"><div><span>PTFE COMPOUNDS<\/span><h3>Fillers change behavior<\/h3><ul><li>Wear resistance<\/li><li>Extrusion resistance<\/li><li>Strength<\/li><li>Thermal conductivity<\/li><\/ul><p>Some fillers can reduce compatibility with strong bases, hydrofluoric acid or other specific media.<\/p><\/div><div class=\"is-ffkm\"><span>FFKM COMPOUNDS<\/span><h3>Formulations differ<\/h3><ul><li>Acid resistance<\/li><li>Base and amine resistance<\/li><li>Steam resistance<\/li><li>Oxidizing chemistry<\/li><\/ul><p>Two FFKM grades can produce meaningfully different results in the same chemical.<\/p><\/div><\/div>\n <div class=\"fpt-data-strip\"><span>EXACT COMPOUND<\/span><span>CONCENTRATION<\/span><span>TEMPERATURE<\/span><span>DURATION<\/span><span>MIXTURES<\/span><span>PRESSURE<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-high-temp\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">05<\/span><div><p>HEAT WITH DIFFERENT LIMITS<\/p><h2>FFKM vs PTFE at High Temperature<\/h2><\/div><\/div>\n <p>Both materials perform at elevated temperature, but their advantages depend on the compound and sealing mechanism. Specialized FFKM grades can have published maximum temperatures above 300\u00b0C, while virgin PTFE is commonly used continuously around 260\u00b0C \/ 500\u00b0F.<\/p>\n <figure class=\"fpt-visual fpt-temperature-visual\"><div class=\"fpt-visual-head\"><span>GENERAL TEMPERATURE LANDSCAPE<\/span><strong>Published maxima are screening values\u2014not application guarantees<\/strong><\/div><div class=\"fpt-temperature-stage\"><div class=\"is-ptfe\"><span>VIRGIN PTFE<\/span><i><b>\u2248260\u00b0C<\/b><\/i><small>Typical continuous reference<\/small><\/div><div class=\"is-ffkm\"><span>SPECIALIZED FFKM<\/span><i><b>300\u00b0C+<\/b><\/i><small>Selected grades; service dependent<\/small><\/div><\/div><figcaption>Chemical media, pressure, motion, geometry, thermal cycling and required life can lower the practical limit.<\/figcaption><\/figure>\n <div class=\"fpt-warning\"><span>DO NOT SELECT BY MAXIMUM ALONE<\/span><p>A high-temperature FFKM may not have the right chemistry, while a PTFE design may be limited by fillers, creep, spring material or the mating hardware.<\/p><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-low-temp\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">06<\/span><div><p>THE CRYOGENIC DIVIDE<\/p><h2>FFKM vs PTFE at Low Temperature<\/h2><\/div><\/div>\n <p>PTFE can provide a major advantage in true cryogenic service. Engineered PTFE seal designs are used with liquid nitrogen, hydrogen, oxygen and helium at temperatures far below the practical low-temperature limits of typical FFKM compounds.<\/p>\n <div class=\"fpt-cryo-scale\"><div class=\"is-extreme\"><span>\u2248 \u2212260\u00b0C<\/span><b>Engineered PTFE designs<\/b><small>Application and design dependent<\/small><\/div><i><\/i><div class=\"is-special\"><span>\u2248 \u221240\u00b0C<\/span><b>Specialty low-temp FFKM<\/b><small>Compound dependent<\/small><\/div><i><\/i><div><span>\u221210 to \u221225\u00b0C<\/span><b>Typical FFKM ranges<\/b><small>Verify exact grade<\/small><\/div><em>WARMER \u2192<\/em><\/div>\n <div class=\"fpt-application-chips\"><span>LNG<\/span><span>Liquid nitrogen<\/span><span>Liquid oxygen<\/span><span>Hydrogen<\/span><span>Aerospace<\/span><span>Cryogenic valves<\/span><\/div>\n <blockquote><p>For true cryogenic sealing, an engineered PTFE seal is generally a more suitable starting point than an FFKM O-ring.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-friction\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">07<\/span><div><p>SLIDING RESISTANCE<\/p><h2>FFKM vs PTFE Friction<\/h2><\/div><\/div>\n <p>PTFE is the clear starting point when extremely low static and dynamic friction, reduced stick-slip or dry-running behavior is central to the application. FFKM behaves more like rubber and normally produces more friction.<\/p>\n <div class=\"fpt-friction-compare\"><div class=\"is-ffkm\"><span>FFKM<\/span><i><\/i><b>Moderate friction<\/b><small>Excellent for many static duties<\/small><\/div><em>SLIDING FORCE<\/em><div class=\"is-ptfe\"><span>PTFE<\/span><i><\/i><b>Extremely low friction<\/b><small>Self-lubricating dynamic behavior<\/small><\/div><\/div>\n <div class=\"fpt-application-grid\"><div><i>01<\/i><span>Reciprocating rods<\/span><\/div><div><i>02<\/i><span>Rotary shafts<\/span><\/div><div><i>03<\/i><span>Precision actuators<\/span><\/div><div><i>04<\/i><span>Analytical instruments<\/span><\/div><div><i>05<\/i><span>Semiconductor mechanisms<\/span><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-dynamic\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">08<\/span><div><p>MOTION CHANGES THE PRIORITY<\/p><h2>Dynamic Sealing: FFKM or PTFE?<\/h2><\/div><\/div>\n <div class=\"fpt-motion-map\"><div><span>STATIC<\/span><b>FFKM advantage<\/b><small>Recovery + simple O-ring gland<\/small><\/div><i>\u2192<\/i><div><span>SLOW MOVEMENT<\/span><b>Either may work<\/b><small>Chemistry and friction decide<\/small><\/div><i>\u2192<\/i><div><span>HIGH-CYCLE SLIDING<\/span><b>PTFE advantage<\/b><small>Friction + wear dominate<\/small><\/div><\/div>\n <div class=\"fpt-two-panel\"><div class=\"is-ffkm\"><span>FFKM DYNAMIC USE<\/span><h3>Useful when recovery matters<\/h3><ul><li>Critical chemical resistance<\/li><li>Relatively slow movement<\/li><li>Conventional O-ring geometry<\/li><li>Elastic conformity<\/li><\/ul><p>Watch friction, heat and wear as speed and cycling rise.<\/p><\/div><div><span>PTFE DYNAMIC USE<\/span><h3>Designed around sliding<\/h3><ul><li>Reciprocating motion<\/li><li>Rotary motion<\/li><li>Dry running<\/li><li>Precision movement<\/li><\/ul><p>Match filler, counterface hardness, surface finish, speed and lubrication.<\/p><\/div><\/div>\n <div class=\"fpt-source-note\"><b>Counterface note:<\/b> Some wear-resistant PTFE fillers can accelerate shaft wear when the mating surface is too soft. Treat the seal and counterface as one tribological system.<\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-spring\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">09<\/span><div><p>PTFE + CONTINUOUS FORCE<\/p><h2>Spring Energized PTFE vs FFKM O-Rings<\/h2><\/div><\/div>\n <p>A spring energized seal combines a PTFE or engineered polymer jacket with a metallic spring that continuously pushes the sealing lips against the hardware.<\/p>\n <figure class=\"fpt-visual fpt-spring-visual\"><div class=\"fpt-visual-head\"><span>SPRING-LOAD TRADE-OFF<\/span><strong>Contact force can be tuned for leakage, friction and wear<\/strong><\/div><div class=\"fpt-spring-stage\"><div><span>LIGHT SPRING<\/span><i class=\"is-light\"><\/i><b>Lower friction<\/b><small>Reduced wear and drive load<\/small><\/div><em>\u2194<\/em><div class=\"is-center\"><span>APPLICATION TARGET<\/span><i><\/i><b>Balanced contact<\/b><small>Leakage + friction + life<\/small><\/div><em>\u2194<\/em><div><span>HEAVY SPRING<\/span><i class=\"is-heavy\"><\/i><b>Higher sealing force<\/b><small>More friction and lip load<\/small><\/div><\/div><figcaption>Spring type, alloy and load are part of the seal specification\u2014not interchangeable details.<\/figcaption><\/figure>\n <div class=\"fpt-material-choice\"><div><span>CHOOSE AN FFKM O-RING WHEN<\/span><ul><li>Standard O-ring gland is preferred<\/li><li>Static sealing dominates<\/li><li>Elastic recovery is important<\/li><li>Very high temperature is required<\/li><li>Installation simplicity matters<\/li><\/ul><\/div><div class=\"is-ptfe\"><span>CHOOSE SPRING ENERGIZED PTFE WHEN<\/span><ul><li>Friction must be minimized<\/li><li>Dry running is required<\/li><li>Cryogenic or demanding vacuum duty exists<\/li><li>Dynamic movement is important<\/li><li>Elastomer compression set is problematic<\/li><\/ul><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-vacuum\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">10<\/span><div><p>LEAK RATE + MATERIAL BEHAVIOR<\/p><h2>FFKM vs PTFE for Vacuum Applications<\/h2><\/div><\/div>\n <p>Both materials are used in vacuum systems. The correct choice depends on whether elastic conformity, low friction, permeability, cryogenic capability or process purity limits performance.<\/p>\n <div class=\"fpt-vacuum-layout\"><div class=\"is-ffkm\"><span>FFKM ADVANTAGES<\/span><h3>Elastic static sealing<\/h3><ul><li>Continuous contact force<\/li><li>Good groove conformity<\/li><li>High-temperature capability<\/li><li>Conventional installation<\/li><li>Special low-outgassing grades<\/li><\/ul><\/div><div class=\"fpt-vacuum-core\"><span>VACUUM SYSTEM<\/span><i><\/i><b>Required leak rate<\/b><\/div><div class=\"is-ptfe\"><span>PTFE ADVANTAGES<\/span><h3>Engineered low-friction sealing<\/h3><ul><li>Low gas permeability<\/li><li>Low friction<\/li><li>Cryogenic capability<\/li><li>Broad chemical resistance<\/li><li>Spring energized options<\/li><\/ul><\/div><\/div>\n <div class=\"fpt-data-strip\"><span>OUTGASSING<\/span><span>PERMEATION<\/span><span>CROSS-SECTION<\/span><span>SURFACE FINISH<\/span><span>TEMPERATURE<\/span><span>LEAK RATE<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-pressure\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">11<\/span><div><p>GLAND DESIGN STILL RULES<\/p><h2>Pressure and Extrusion Resistance<\/h2><\/div><\/div>\n <p>Neither FFKM nor virgin PTFE should be specified for high pressure without reviewing clearance, temperature, compound deformation and backup support.<\/p>\n <div class=\"fpt-pressure-compare\"><div class=\"is-ffkm\"><span>FFKM RISK<\/span><h3>Extrusion through clearance<\/h3><p>Pressure, temperature, swelling, softness and a large gap can produce nibbled or torn edges.<\/p><b>HARDNESS \u00b7 GAP \u00b7 BACKUP RING<\/b><\/div><div class=\"is-ptfe\"><span>PTFE RISK<\/span><h3>Creep under sustained load<\/h3><p>Virgin PTFE can cold-flow; filled compounds improve compressive strength, wear and deformation resistance.<\/p><b>FILLER \u00b7 PROFILE \u00b7 SUPPORT MATERIAL<\/b><\/div><\/div>\n <figure class=\"fpt-visual fpt-gap-visual\"><div class=\"fpt-visual-head\"><span>HIGH-PRESSURE STACK<\/span><strong>Support can be as important as the primary seal material<\/strong><\/div><div class=\"fpt-gap-stage\"><div><span>PRESSURE<\/span><em>\u2192<\/em><i class=\"fpt-primary\"><\/i><i class=\"fpt-backup\"><\/i><i class=\"fpt-metal-top\"><\/i><i class=\"fpt-metal-bottom\"><\/i><b>CONTROLLED GAP<\/b><\/div><aside><span>OPTIONAL SUPPORT<\/span><p>Filled PTFE, PEEK or another high-strength material may be used as a backup element in severe duty.<\/p><\/aside><\/div><figcaption>Review peak pressure and cycling\u2014not only the normal gauge reading.<\/figcaption><\/figure>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-semiconductor\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">12<\/span><div><p>ONE TOOL, MULTIPLE MATERIALS<\/p><h2>FFKM vs PTFE for Semiconductor Equipment<\/h2><\/div><\/div>\n <p>Semiconductor systems frequently use both materials in different locations because static chamber sealing and precision chemical-delivery motion create different priorities.<\/p>\n <div class=\"fpt-semiconductor-map\"><div class=\"is-ffkm\"><span>FFKM ZONE<\/span><b>Chamber O-rings<\/b><b>Vacuum flanges<\/b><b>Process valves<\/b><b>Plasma chamber seals<\/b><small>Recovery \u00b7 purity \u00b7 heat \u00b7 plasma<\/small><\/div><i>+<\/i><div class=\"is-ptfe\"><span>PTFE ZONE<\/span><b>Chemical delivery<\/b><b>Dynamic valve seals<\/b><b>Spring energized seals<\/b><b>Precision motion<\/b><small>Friction \u00b7 dry running \u00b7 wet chemistry<\/small><\/div><\/div>\n <blockquote><p>The correct result may be a mixed-material sealing architecture rather than one universal material across the tool.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-pumps\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">13<\/span><div><p>LOCATION DETERMINES FUNCTION<\/p><h2>FFKM vs PTFE for Chemical Pumps and Valves<\/h2><\/div><\/div>\n <div class=\"fpt-equipment-map\"><div><span>STATIC BODY JOINT<\/span><b>FFKM O-ring<\/b><small>Pump casing \u00b7 valve body \u00b7 cartridge<\/small><\/div><i>\u2192<\/i><div><span>SLIDING INTERFACE<\/span><b>PTFE seal<\/b><small>Valve stem \u00b7 shaft \u00b7 dynamic seat<\/small><\/div><i>\u2192<\/i><div><span>DEMANDING DYNAMIC<\/span><b>Spring energized PTFE<\/b><small>Low friction \u00b7 vacuum \u00b7 long life<\/small><\/div><\/div>\n <div class=\"fpt-five-inputs\"><span>CHEMICAL MEDIA<\/span><span>PRESSURE<\/span><span>MOTION<\/span><span>TEMPERATURE<\/span><span>LEAKAGE REQUIREMENT<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-deformation\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">14<\/span><div><p>DIFFERENT LONG-TERM FAILURE MODES<\/p><h2>Compression Set vs Creep<\/h2><\/div><\/div>\n <div class=\"fpt-deformation-compare\"><div class=\"is-ffkm\"><span>FFKM \u00b7 COMPRESSION SET<\/span><i><\/i><h3>Elastic recovery is lost<\/h3><p>Heat, compression and chemicals can leave a permanent flat shape, reduce contact force and cause leakage.<\/p><\/div><div class=\"is-ptfe\"><span>PTFE \u00b7 CREEP \/ COLD FLOW<\/span><i><\/i><h3>Material deforms under load<\/h3><p>Time, pressure and temperature can change the profile; fillers, geometry and energization are used to control it.<\/p><\/div><\/div>\n <div class=\"fpt-equation\"><span>FFKM DESIGN<\/span><b>RECOVERY + COMPRESSION SET<\/b><i>vs<\/i><span>PTFE DESIGN<\/span><b>CREEP + ENERGIZATION<\/b><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-installation\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">15<\/span><div><p>ASSEMBLY FOLLOWS MATERIAL BEHAVIOR<\/p><h2>Installation Differences<\/h2><\/div><\/div>\n <div class=\"fpt-install-grid\"><div class=\"is-ffkm\"><span>FFKM O-RING<\/span><h3>Conventional gland installation<\/h3><ul><li>Avoid cuts and sharp edges<\/li><li>Prevent twisting<\/li><li>Use compatible lubrication<\/li><li>Control stretch<\/li><li>Confirm squeeze and fill<\/li><\/ul><\/div><div class=\"is-ptfe\"><span>PTFE SEAL<\/span><h3>Specialized tools may be required<\/h3><ul><li>Installation cones<\/li><li>Sizing tools<\/li><li>Split glands<\/li><li>Special assembly procedures<\/li><li>Correct pressure orientation<\/li><\/ul><\/div><\/div>\n <div class=\"fpt-orientation-card\"><span>SPRING ENERGIZED SEAL<\/span><div><b>PRESSURE SIDE<\/b><i>\u2192<\/i><em>OPEN JACKET \/ SPRING CAVITY<\/em><i>\u2192<\/i><b>SEALING LIPS<\/b><\/div><p>Installing a directional seal backward can prevent proper pressure energization.<\/p><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-cost\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">16<\/span><div><p>COMPARE THE COMPLETE SYSTEM<\/p><h2>Is FFKM or PTFE More Expensive?<\/h2><\/div><\/div>\n <p>There is no universal answer. FFKM molded parts have premium material cost, while a machined filled-PTFE profile, spring energized jacket and specialty alloy spring can also be expensive.<\/p>\n <div class=\"fpt-cost-equation\"><div><span>SEAL<\/span><b>Part price<\/b><\/div><i>+<\/i><div><span>HARDWARE<\/span><b>New gland or counterface<\/b><\/div><i>+<\/i><div><span>INSTALL<\/span><b>Tools and labor<\/b><\/div><i>+<\/i><div><span>RISK<\/span><b>Leakage + downtime<\/b><\/div><i>\u00d7<\/i><div><span>FREQUENCY<\/span><b>Replacement interval<\/b><\/div><em>= TOTAL SEALING COST<\/em><\/div>\n <div class=\"fpt-two-panel\"><div class=\"is-ffkm\"><span>FFKM EXAMPLE<\/span><h3>Higher material, familiar gland<\/h3><p>A premium O-ring may fit the existing groove and avoid hardware redesign.<\/p><\/div><div><span>PTFE CONVERSION EXAMPLE<\/span><h3>New geometry, longer dynamic life<\/h3><p>A spring energized conversion may require a new gland but reduce friction and replacement frequency.<\/p><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-choose-ffkm\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">17<\/span><div><p>ELASTIC EXTREME-SERVICE SEALING<\/p><h2>When Should You Choose FFKM?<\/h2><\/div><\/div>\n <div class=\"fpt-choice-card is-ffkm\"><div><span>FFKM IS USUALLY THE BETTER CANDIDATE WHEN<\/span><h3>Recovery and static sealing lead the specification.<\/h3><ul><li>You want a conventional elastomer O-ring<\/li><li>Static sealing dominates<\/li><li>Broad chemical resistance is required<\/li><li>Extreme high-temperature capability is needed<\/li><li>Elastic recovery is important<\/li><li>High-purity elastomer sealing is required<\/li><\/ul><\/div><aside><span>TYPICAL APPLICATIONS<\/span><b>Chemical reactors<\/b><b>Semiconductor chambers<\/b><b>Chemical pumps<\/b><b>Pharmaceutical valves<\/b><b>High-temperature systems<\/b><\/aside><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-choose-ptfe\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">18<\/span><div><p>LOW-FRICTION ENGINEERED SEALING<\/p><h2>When Should You Choose PTFE?<\/h2><\/div><\/div>\n <div class=\"fpt-choice-card is-ptfe\"><div><span>PTFE IS OFTEN THE BETTER CANDIDATE WHEN<\/span><h3>Motion, friction or extreme low temperature lead.<\/h3><ul><li>Friction must be very low<\/li><li>Dry running is required<\/li><li>Cryogenic temperatures are involved<\/li><li>Dynamic movement is significant<\/li><li>Chemical compatibility must be extremely broad<\/li><li>Elastomer swelling is unacceptable<\/li><\/ul><\/div><aside><span>TYPICAL APPLICATIONS<\/span><b>Rotary equipment<\/b><b>Reciprocating systems<\/b><b>Cryogenic valves<\/b><b>Chemical valves<\/b><b>HPLC equipment<\/b><b>Semiconductor mechanisms<\/b><\/aside><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-choose-spring\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">19<\/span><div><p>PTFE PROPERTIES + MECHANICAL FORCE<\/p><h2>When Should You Choose a Spring Energized PTFE Seal?<\/h2><\/div><\/div>\n <div class=\"fpt-spring-combination\"><div><span>AGGRESSIVE CHEMICAL<\/span><\/div><i>+<\/i><div><span>LOW PRESSURE \/ VACUUM<\/span><\/div><i>+<\/i><div><span>EXTREME TEMPERATURE<\/span><\/div><i>+<\/i><div><span>LOW FRICTION<\/span><\/div><i>+<\/i><div><span>DYNAMIC MOVEMENT<\/span><\/div><em>SPRING ENERGIZED PTFE<\/em><\/div>\n <blockquote><p>The spring provides continuous sealing force that PTFE cannot generate through natural elasticity alone.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-selection\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">20<\/span><div><p>INITIAL SCREENING MATRIX<\/p><h2>Practical FFKM vs PTFE Selection Table<\/h2><\/div><\/div>\n <div class=\"fpt-table-wrap\" role=\"region\" aria-label=\"Practical FFKM and PTFE selection table\" tabindex=\"0\"><table><thead><tr><th>Application requirement<\/th><th>Usually consider first<\/th><\/tr><\/thead><tbody>\n <tr><td>Standard extreme-chemical O-ring<\/td><td><b class=\"fpt-label is-ffkm\">FFKM<\/b><\/td><\/tr><tr><td>Static seal above 300\u00b0C<\/td><td><b class=\"fpt-label is-ffkm\">Suitable FFKM compound<\/b><\/td><\/tr><tr><td>Low-friction reciprocating seal<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Rotary shaft sealing<\/td><td><b class=\"fpt-label is-ptfe\">PTFE-based design<\/b><\/td><\/tr><tr><td>Cryogenic sealing<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Semiconductor chamber O-ring<\/td><td><b class=\"fpt-label is-ffkm\">Semiconductor-grade FFKM<\/b><\/td><\/tr><tr><td>Chemical valve seat<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Chemical pump secondary O-ring<\/td><td><b class=\"fpt-label is-ffkm\">FFKM<\/b><\/td><\/tr><tr><td>Dry-running seal<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Low-pressure dynamic seal<\/td><td><b class=\"fpt-label is-spring\">Spring energized PTFE<\/b><\/td><\/tr><tr><td>Conventional elastic O-ring gland<\/td><td><b class=\"fpt-label is-ffkm\">FFKM<\/b><\/td><\/tr><tr><td>Extreme chemical + precision motion<\/td><td><b class=\"fpt-label is-spring\">Spring energized PTFE<\/b><\/td><\/tr>\n <\/tbody><\/table><\/div>\n <p class=\"fpt-table-note\">This is a screening guide, not a final material approval. Verify the exact formulation, geometry and operating conditions.<\/p>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-information\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">21<\/span><div><p>INPUTS BEFORE MATERIAL SELECTION<\/p><h2>Information Needed Before Choosing<\/h2><\/div><\/div>\n <div class=\"fpt-input-grid\"><article><i>01<\/i><h3>Media<\/h3><p>Chemical names, concentrations, gases, cleaners and lubricants.<\/p><\/article><article><i>02<\/i><h3>Temperature<\/h3><p>Startup, normal, continuous maximum and peak.<\/p><\/article><article><i>03<\/i><h3>Pressure \/ vacuum<\/h3><p>Normal, maximum, vacuum level and pressure direction.<\/p><\/article><article class=\"is-motion\"><i>04<\/i><h3>Motion<\/h3><p>Static, reciprocating, rotary or oscillating; include speed, stroke and cycle frequency.<\/p><\/article><article><i>05<\/i><h3>Hardware<\/h3><p>Shaft or bore diameter, groove, clearance and surface finish.<\/p><\/article><article><i>06<\/i><h3>Current failure<\/h3><p>Leakage, swelling, set, friction, extrusion, wear and service life.<\/p><\/article><\/div>\n <a class=\"fpt-inline-cta\" href=\"#fpt-contact\"><span>READY FOR A MATERIAL REVIEW?<\/span><b>Send these six input groups<\/b><i>\u2192<\/i><\/a>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-mistakes\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">22<\/span><div><p>SEVEN AVOIDABLE ERRORS<\/p><h2>Common Selection Mistakes<\/h2><\/div><\/div>\n <div class=\"fpt-mistake-list\"><article><span>01<\/span><div><h3>Assuming PTFE behaves like a rubber O-ring<\/h3><p>Limited recovery often requires a different profile, gland or energizer.<\/p><\/div><\/article><article><span>02<\/span><div><h3>Assuming all FFKM compounds are identical<\/h3><p>Formulations vary substantially in chemical and temperature performance.<\/p><\/div><\/article><article><span>03<\/span><div><h3>Comparing only maximum temperature<\/h3><p>The highest rating may not suit the actual chemical, motion or service life.<\/p><\/div><\/article><article><span>04<\/span><div><h3>Ignoring PTFE fillers<\/h3><p>Fillers change wear, creep, pressure capability and chemical compatibility.<\/p><\/div><\/article><article><span>05<\/span><div><h3>Ignoring motion<\/h3><p>A strong static material choice may fail in high-speed dynamic service.<\/p><\/div><\/article><article><span>06<\/span><div><h3>Putting PTFE in the same FFKM groove<\/h3><p>The two materials generate and retain sealing force differently.<\/p><\/div><\/article><article><span>07<\/span><div><h3>Choosing by part price alone<\/h3><p>Hardware conversion, downtime, leakage risk and replacement frequency matter.<\/p><\/div><\/article><\/div>\n <\/section>\n\n <section class=\"fpt-section fpt-summary-section\" id=\"fpt-summary\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">23<\/span><div><p>MATERIAL NAME IS THE START<\/p><h2>Choose the Complete Sealing System<\/h2><\/div><\/div>\n <div class=\"fpt-summary-pair\"><div class=\"is-ffkm\"><span>FFKM IS AN ELASTOMER<\/span><b>Elastic recovery<\/b><b>Conventional O-ring sealing<\/b><b>Exceptional chemical resistance<\/b><b>Very high temperature capability<\/b><\/div><div class=\"is-ptfe\"><span>PTFE IS A FLUOROPOLYMER<\/span><b>Extremely low friction<\/b><b>Dry-running behavior<\/b><b>Exceptional cryogenic capability<\/b><b>Engineered dynamic sealing<\/b><\/div><\/div>\n <div class=\"fpt-summary-inputs\"><span>CHEMICAL<\/span><i>+<\/i><span>TEMPERATURE<\/span><i>+<\/i><span>PRESSURE<\/span><i>+<\/i><span>MOTION<\/span><i>+<\/i><span>GROOVE<\/span><i>+<\/i><span>SERVICE LIFE<\/span><b>= RIGHT SEAL<\/b><\/div>\n <blockquote><p>Neither FFKM nor PTFE should be selected by material name alone. Select the compound, profile, energizer, gland and counterface as one system.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-faq\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">24<\/span><div><p>QUICK ANSWERS<\/p><h2>Frequently Asked Questions<\/h2><\/div><\/div>\n <div class=\"fpt-faq-list\">\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Is FFKM the same as PTFE?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>No. FFKM is a perfluoroelastomer with rubber-like elasticity. PTFE is a fluoropolymer with very low friction and limited natural elastic recovery.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which has better chemical resistance?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Both provide exceptionally broad resistance. The exact FFKM formulation, PTFE compound, chemistry and operating conditions must be checked.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which has better high-temperature resistance?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Specialized FFKM grades can have published maxima above 300\u00b0C. Virgin PTFE is commonly used continuously around 260\u00b0C, although engineered compounds vary.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which is better at low temperatures?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>PTFE generally has a major advantage in extreme low-temperature and cryogenic applications.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which has lower friction?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>PTFE generally provides much lower friction than FFKM.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Can PTFE replace an FFKM O-ring?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Not as a direct substitution in many cases. PTFE has different recovery and creep behavior and may need a different groove or spring energizer.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Can FFKM replace PTFE?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Sometimes in static O-ring applications, but it may create more friction and have less low-temperature capability.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>What is a spring energized PTFE seal?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>It is a PTFE or engineered polymer jacket containing a metal spring that continuously pushes the sealing lips against the hardware.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which is better for vacuum?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Both can work. FFKM is convenient for elastic static sealing, while energized PTFE can offer advantages in demanding vacuum, low-friction and cryogenic duty.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which is better for semiconductor equipment?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Both are used in different locations: FFKM commonly serves chambers and static seals, while PTFE-based seals often serve dynamic mechanisms and chemical delivery.<\/p><\/div><\/div>\n <\/div>\n <\/section>\n\n <section class=\"fpt-contact\" id=\"fpt-contact\"><div class=\"fpt-contact-grid\"><div><span class=\"fpt-eyebrow\">CUSTOM FFKM & PTFE SEALING<\/span><h2>Need Help Choosing Between FFKM and PTFE?<\/h2><p>Walle Seals manufactures custom FFKM O-rings, gaskets, molded components, filled PTFE profiles and spring energized sealing solutions.<\/p><a href=\"\/contact-us\/\" class=\"fpt-button is-light\">Discuss your application <i>\u2192<\/i><\/a><\/div><div class=\"fpt-contact-spec\"><span>SEND US<\/span><ul><li>Chemicals and concentrations<\/li><li>Temperature range<\/li><li>Pressure or vacuum level<\/li><li>Static, reciprocating or rotary motion<\/li><li>Seal and groove dimensions<\/li><li>Surface finish and hardware material<\/li><li>Failure symptoms and required life<\/li><\/ul><\/div><\/div><\/section>\n <\/article>\n <\/main>\n <\/div>\n <button class=\"fpt-back-top\" type=\"button\" data-fpt-back-top aria-label=\"Back to top\"><span>\u2191<\/span><\/button>\n<\/div>\n <script>\n\/* WordPress JavaScript \u6a21\u5757\uff1a\u590d\u5236\u672c\u6587\u4ef6\u5168\u90e8\u5185\u5bb9\uff0c\u4e0d\u8981\u6dfb\u52a0 script \u6807\u7b7e\uff1b\u65e0\u9700 jQuery\u3002 *\/\n(function () {\n \"use strict\";\n\n function init(root) {\n if (!root) return;\n if (root.dataset.fptReady === \"true\") return;\n root.dataset.fptReady = \"true\";\n\n var article = root.querySelector(\"[data-fpt-article]\");\n var progress = root.querySelector(\"[data-fpt-progress]\");\n var backTop = root.querySelector(\"[data-fpt-back-top]\");\n var toc = root.querySelector(\"[data-fpt-toc]\");\n var toggle = root.querySelector(\"[data-fpt-toc-toggle]\");\n var shell = root.querySelector(\"[data-fpt-shell]\");\n var sidebar = root.querySelector(\"[data-fpt-sidebar]\");\n var card = root.querySelector(\"[data-fpt-sidebar-card]\");\n var links = toc ? 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CONSIDER FIRST: FFKM\",\n title: \"Use natural recovery in a conventional O-ring gland.\",\n copy: \"For static sealing with aggressive chemistry and high temperature, FFKM provides contact force without a separate energizer.\",\n check: \"Exact chemistry \u00b7 temperature \u00b7 compression set \u00b7 groove fill\",\n href: \"#fpt-choose-ffkm\"\n },\n recip: {\n status: \"Low-friction reciprocating duty\",\n kicker: \"USUALLY CONSIDER FIRST: SPRING ENERGIZED PTFE\",\n title: \"Combine low-friction lips with controlled spring force.\",\n copy: \"Reciprocating motion turns friction, wear, surface finish and stick-slip into primary design inputs.\",\n check: \"Speed \u00b7 stroke \u00b7 cycles \u00b7 lubrication \u00b7 counterface \u00b7 spring load\",\n href: \"#fpt-choose-spring\"\n },\n rotary: {\n status: \"Rotary shaft duty\",\n kicker: \"USUALLY CONSIDER FIRST: PTFE-BASED DESIGN\",\n title: \"Prioritize friction, heat generation and counterface wear.\",\n copy: \"PTFE compounds and profiles can be matched to speed, runout, lubrication, shaft finish and temperature.\",\n check: \"Surface speed \u00b7 shaft hardness \u00b7 finish \u00b7 runout \u00b7 lubrication\",\n href: \"#fpt-choose-ptfe\"\n },\n cryo: {\n status: \"Extreme low-temperature duty\",\n kicker: \"USUALLY CONSIDER FIRST: ENGINEERED PTFE\",\n title: \"Use a material system designed for cryogenic contraction.\",\n copy: \"PTFE retains usefulness at temperatures far below typical FFKM limits, but the jacket, spring and hardware must be designed together.\",\n check: \"Minimum temperature \u00b7 fluid \u00b7 contraction \u00b7 spring alloy \u00b7 leak rate\",\n href: \"#fpt-low-temp\"\n },\n vacuum: {\n status: \"Demanding vacuum seal\",\n kicker: \"COMPARE FFKM AND ENERGIZED PTFE\",\n title: \"Let leak rate, motion and temperature decide.\",\n copy: \"FFKM offers elastic static conformity; energized PTFE can add low friction, cryogenic capability and continuous lip load.\",\n check: \"Vacuum level 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Seals: Which Material Is Right for Your Application? Compare how elasticity, creep, friction, temperature, pressure, vacuum and motion change the correct choice between an FFKM O-ring and an engineered PTFE seal. Compare the materials \u2193 Open the […]<\/p>\n","protected":false},"author":1,"featured_media":7030,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_themeisle_gutenberg_block_has_review":false,"footnotes":""},"categories":[85,106],"tags":[],"class_list":["post-6827","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-materials-compatibility"],"_links":{"self":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts\/6827","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/comments?post=6827"}],"version-history":[{"count":1,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts\/6827\/revisions"}],"predecessor-version":[{"id":6828,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts\/6827\/revisions\/6828"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/media\/7030"}],"wp:attachment":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/media?parent=6827"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/categories?post=6827"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/tags?post=6827"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":6827,"date":"2026-09-29T15:54:58","date_gmt":"2026-09-29T07:54:58","guid":{"rendered":"https:\/\/walleglobal.com\/?p=6827"},"modified":"2026-09-29T15:55:00","modified_gmt":"2026-09-29T07:55:00","slug":"fkm-vs-joints-ptfe","status":"publish","type":"post","link":"https:\/\/walleglobal.com\/fr\/2026\/09\/ffkm-vs-ptfe-seals\/","title":{"rendered":"FFKM vs joints en PTFE : diff\u00e9rences cl\u00e9s et guide de s\u00e9lection"},"content":{"rendered":"\n\n\n\n \n \n \n FFKM vs PTFE Seals \u2014 WordPress Page Preview<\/title>\n <style>\nhtml, body { margin: 0; padding: 0; }\n\/* WordPress\u300c\u5916\u89c2 \u2192 \u81ea\u5b9a\u4e49 \u2192 \u989d\u5916 CSS\u300d\uff1a\u590d\u5236\u672c\u6587\u4ef6\u5168\u90e8\u5185\u5bb9\u3002\u5168\u90e8\u89c4\u5219\u4f7f\u7528 fpt \u547d\u540d\u7a7a\u95f4\u3002 *\/\n.fpt-page,\n.fpt-page * { box-sizing: border-box; }\n.fpt-page {\n --ink: #1c2635;\n --muted: #697689;\n --line: #dde3ec;\n --paper: #fff;\n --soft: #f6f8fb;\n --deep: #080d18;\n 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}\n.fpt-selector-controls button:hover { border-color: #7c89a3; transform: translateY(-1px); }\n.fpt-selector-controls button.is-active { border-color: var(--cyan); color: #10262d; background: linear-gradient(135deg,#adf5f4,var(--cyan)); }\n.fpt-selector-controls button i { color: #7d889e; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-selector-controls button.is-active i { color: #2d7480; }\n.fpt-selector-controls button span { font-size: 10px; font-weight: 820; }\n.fpt-selector-stage { position: relative; min-height: 380px; overflow: hidden; border-right: 1px solid rgba(190,202,228,.15); background: radial-gradient(circle at 50% 50%,#273249,#151f33 66%); }\n.fpt-scale { position: absolute; top: 35px; right: 25px; left: 25px; display: grid; grid-template-columns: auto 1fr auto; gap: 9px; align-items: center; }\n.fpt-scale span { color: #8390a6; font-size: 6px; font-weight: 900; letter-spacing: .08em; }\n.fpt-scale i { height: 2px; background: linear-gradient(90deg,var(--purple),var(--cyan)); }\n.fpt-choice { position: absolute; display: grid; place-items: center; width: 96px; height: 96px; border: 2px solid #59677f; border-radius: 50%; opacity: .35; transition: opacity .24s ease,transform .24s ease,box-shadow .24s ease; }\n.fpt-choice b { color: #edf4ff; font-size: 16px; }\n.fpt-choice small { margin-top: -25px; color: #8793a8; font-size: 6px; font-weight: 900; }\n.fpt-choice.is-ffkm { top: 103px; left: 27px; border-color: #8566c8; background: #2f2351; }\n.fpt-choice.is-ptfe { top: 103px; right: 27px; border-color: #398d9b; background: #183d47; }\n.fpt-choice.is-spring { bottom: 51px; left: 50%; width: 107px; height: 107px; border-color: #9a8c61; background: #3a3425; transform: translateX(-50%); }\n.fpt-selector.is-static .fpt-choice.is-ffkm,\n.fpt-selector.is-heat .fpt-choice.is-ffkm,\n.fpt-selector.is-recip .fpt-choice.is-spring,\n.fpt-selector.is-vacuum .fpt-choice.is-spring,\n.fpt-selector.is-rotary .fpt-choice.is-ptfe,\n.fpt-selector.is-cryo .fpt-choice.is-ptfe { opacity: 1; box-shadow: 0 0 25px rgba(81,212,218,.27); }\n.fpt-selector.is-recip .fpt-choice.is-spring,\n.fpt-selector.is-vacuum .fpt-choice.is-spring { transform: translateX(-50%) scale(1.12); }\n.fpt-selector.is-static .fpt-choice.is-ffkm,\n.fpt-selector.is-heat .fpt-choice.is-ffkm,\n.fpt-selector.is-rotary .fpt-choice.is-ptfe,\n.fpt-selector.is-cryo .fpt-choice.is-ptfe { transform: scale(1.12); }\n.fpt-selector-result { padding: 27px 24px; background: radial-gradient(circle at 100% 0,rgba(81,212,218,.1),transparent 50%); }\n.fpt-selector-result > span { color: #a7eff0; font-size: 8px; font-weight: 900; letter-spacing: .14em; }\n.fpt-selector-result h3 { margin: 11px 0 12px; color: #f1f6ff; font-size: 22px; }\n.fpt-selector-result > p { margin-bottom: 19px; color: #aab5c8; font-size: 11px; line-height: 1.65; }\n.fpt-selector-result > div { padding: 14px; border: 1px solid #46546b; border-radius: 9px; background: rgba(255,255,255,.025); }\n.fpt-selector-result > div b { color: var(--amber); font-size: 8px; letter-spacing: .13em; }\n.fpt-selector-result > div p { margin: 5px 0 0; color: #cbd4e3; font-size: 10px; }\n.fpt-selector-result > a { display: inline-flex; margin-top: 18px; color: #a8eff0; font-size: 10px; font-weight: 830; }\n.fpt-tool-note { margin: 0 !important; padding: 13px 24px; border-top: 1px solid rgba(190,202,228,.12); color: #77859b !important; font-size: 9px; }\n\n.fpt-table-wrap { margin: 31px 0; overflow-x: auto; border: 1px solid #dce3ec; border-radius: 14px; background: #fff; box-shadow: 0 18px 50px rgba(28,39,69,.06); }\n.fpt-table-wrap table { width: 100%; min-width: 650px; border-collapse: collapse; }\n.fpt-table-wrap th { padding: 16px 19px; color: #f2f6ff; background: #172137; font-size: 9px; font-weight: 900; letter-spacing: .1em; text-align: left; text-transform: uppercase; }\n.fpt-table-wrap th:nth-child(2) { background: #3b2d62; }\n.fpt-table-wrap th:nth-child(3) { background: #173d48; }\n.fpt-table-wrap td { padding: 14px 19px; border-top: 1px solid #e2e7ef; color: #536075; font-size: 11px; line-height: 1.5; }\n.fpt-table-wrap td:first-child { color: #29364c; font-weight: 730; }\n.fpt-table-wrap tr:nth-child(even) td { background: #f8f9fb; }\n.fpt-table-wrap tr:hover td { background: #f3f1fb; }\n.fpt-table-note { margin-top: -18px !important; color: #7d8899 !important; font-size: 10px; }\n.fpt-visual { margin: 34px 0 31px; overflow: hidden; border: 1px solid #dce3ec; border-radius: 17px; background: #f7f8fb; box-shadow: 0 20px 54px rgba(27,38,67,.07); }\n.fpt-visual-head { display: flex; align-items: center; justify-content: space-between; gap: 22px; padding: 17px 21px; border-bottom: 1px solid #dce3ec; background: rgba(255,255,255,.84); }\n.fpt-visual-head span { color: #6750a5; font-size: 9px; font-weight: 900; letter-spacing: .15em; }\n.fpt-visual-head strong { color: #424e62; font-size: 11px; text-align: right; }\n.fpt-visual figcaption { padding: 14px 21px; border-top: 1px solid #dce3ec; color: #788396; background: #fff; font-size: 10px; line-height: 1.55; }\n.fpt-warning { display: grid; grid-template-columns: auto 1fr; gap: 17px; align-items: start; margin: 28px 0; padding: 20px 22px; border: 1px solid #ead29e; border-radius: 12px; background: #fffaf0; }\n.fpt-warning span { padding: 4px 8px; border-radius: 5px; color: #654600; background: #ffdc8a; font-size: 8px; font-weight: 900; letter-spacing: .11em; }\n.fpt-warning p { margin: 0; color: #645942; font-size: 12px; line-height: 1.62; }\n.fpt-source-note { margin: 27px 0 0 !important; padding: 17px 19px; border-left: 4px solid var(--cyan); border-radius: 0 10px 10px 0; color: #536175 !important; background: #f0f8fa; font-size: 11px; line-height: 1.65; }\n\n.fpt-recovery-stage { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; gap: 19px; align-items: center; padding: 36px 30px; }\n.fpt-recovery-stage > div { min-height: 210px; padding: 20px; border: 1px solid #dce2eb; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-recovery-stage > em { color: #909aaa; font-size: 8px; font-style: normal; font-weight: 900; text-align: center; }\n.fpt-recovery-stage > div > span { color: #684ab7; font-size: 8px; font-weight: 900; letter-spacing: .11em; }\n.fpt-recovery-stage i { display: block; width: 103px; height: 103px; margin: 25px auto; border: 28px solid #7952cd; border-radius: 50%; }\n.fpt-recovery-stage .is-loaded i { height: 72px; margin-top: 40px; margin-bottom: 41px; border-top-width: 18px; border-bottom-width: 18px; }\n.fpt-recovery-stage .is-energized i { box-shadow: inset 18px 0 0 rgba(81,212,218,.45),-13px 0 0 rgba(81,212,218,.22); }\n.fpt-recovery-stage b,\n.fpt-recovery-stage small { display: block; }\n.fpt-recovery-stage b { color: #37445a; font-size: 11px; }\n.fpt-recovery-stage small { margin-top: 5px; color: #838d9d; font-size: 9px; }\n.fpt-chip-grid { display: flex; flex-wrap: wrap; gap: 8px; margin: 29px 0; }\n.fpt-chip-grid span { padding: 8px 12px; border: 1px solid #d8cef0; border-radius: 999px; color: #684ca6; background: #f5f1fc; font-size: 9px; font-weight: 800; }\n.fpt-chip-grid.is-cyan span { border-color: #c9e4e8; color: #28798b; background: #eff9fa; }\n.fpt-evidence-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 12px; margin: 31px 0; }\n.fpt-evidence-grid > div { padding: 22px 20px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-evidence-grid > div > span { color: #684ba8; font-size: 8px; font-weight: 900; letter-spacing: .14em; }\n.fpt-evidence-grid h3 { margin: 11px 0 10px; font-size: 17px; }\n.fpt-evidence-grid p { margin: 0; color: #697587; font-size: 10px; line-height: 1.6; }\n.fpt-evidence-grid .is-dark { border-color: #4e5c73; background: #172137; }\n.fpt-evidence-grid .is-dark > span { color: var(--cyan); }\n.fpt-evidence-grid .is-dark h3 { color: #f2f6ff; }\n.fpt-evidence-grid .is-dark p { color: #acb7c9; }\n\n.fpt-ptfe-stage { position: relative; display: grid; grid-template-columns: 1fr .8fr 1fr; gap: 23px; align-items: center; padding: 42px 35px; }\n.fpt-ptfe-stage > div { position: relative; min-height: 210px; padding: 20px; border: 1px solid #dce3ec; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-ptfe-stage span { color: #24798a; font-size: 8px; font-weight: 900; letter-spacing: .11em; }\n.fpt-ptfe-stage b { display: block; margin-top: 141px; color: #425268; font-size: 10px; }\n.fpt-jacket-left,\n.fpt-jacket-right { position: absolute; top: 64px; width: 38px; height: 77px; border: 2px solid #79d4d9; background: linear-gradient(#dfffff,#6ec8cf); }\n.fpt-jacket-left { right: 36%; border-radius: 6px 16px 16px 6px; }\n.fpt-jacket-right { left: 36%; border-radius: 16px 6px 6px 16px; }\n.fpt-spring-core { background: #172137 !important; }\n.fpt-spring-core span { color: var(--amber); }\n.fpt-spring-core i { position: absolute; top: 82px; right: 25%; left: 25%; height: 45px; background: repeating-linear-gradient(135deg,transparent 0 9px,#ffca68 10px 14px,transparent 15px 23px); }\n.fpt-spring-core b { color: #d8e3f2; }\n.fpt-hardware-top,\n.fpt-hardware-bottom { position: absolute; right: 17%; left: 17%; height: 35px; border-radius: 5px; background: linear-gradient(#bbc9d0,#687984); }\n.fpt-hardware-top { top: 60px; }\n.fpt-hardware-bottom { top: 115px; }\n\n.fpt-mechanism-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-mechanism-compare > div { padding: 25px 24px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-mechanism-compare > div > span { font-size: 9px; font-weight: 900; letter-spacing: .14em; }\n.fpt-mechanism-compare h3 { margin: 10px 0 13px; font-size: 20px; }\n.fpt-mechanism-compare ol { margin: 0 0 20px; padding-left: 21px; }\n.fpt-mechanism-compare li { padding: 5px 0; color: #687487; font-size: 10px; }\n.fpt-mechanism-compare > div > b { display: block; padding: 10px; border-radius: 7px; font-size: 8px; text-align: center; }\n.fpt-mechanism-compare .is-ffkm { border-color: #cfc1ee; background: #f5f1fc; }\n.fpt-mechanism-compare .is-ffkm > span { color: #6f4dc1; }\n.fpt-mechanism-compare .is-ffkm > b { color: #eaddff; background: #51388d; }\n.fpt-mechanism-compare .is-ptfe { border-color: #c8e2e6; background: #f0f9fa; }\n.fpt-mechanism-compare .is-ptfe > span { color: #217b8d; }\n.fpt-mechanism-compare .is-ptfe > b { color: #dffcff; background: #176c7d; }\n\n.fpt-chemical-path { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr auto 1.15fr; gap: 9px; align-items: center; margin: 31px 0; padding: 25px 20px; border: 1px solid #dde3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-chemical-path > div { min-height: 118px; padding: 17px 14px; border: 1px solid #dce2eb; border-radius: 10px; background: #fff; }\n.fpt-chemical-path > i { color: #929cad; font-style: normal; }\n.fpt-chemical-path span,\n.fpt-chemical-path b { display: block; }\n.fpt-chemical-path span { color: #6950a6; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-chemical-path b { margin-top: 15px; color: #48546a; font-size: 10px; line-height: 1.5; }\n.fpt-chemical-path .is-result { border-color: #4b5b72; background: #172137; }\n.fpt-chemical-path .is-result span { color: var(--cyan); }\n.fpt-chemical-path .is-result b { color: #dbe5f3; }\n.fpt-two-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 30px 0; }\n.fpt-two-panel > div { padding: 23px 22px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-two-panel > div > span { color: #247b8d; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-two-panel h3 { margin: 10px 0 12px; font-size: 18px; }\n.fpt-two-panel p { margin: 13px 0 0; font-size: 10px; line-height: 1.58; }\n.fpt-two-panel ul,\n.fpt-material-choice ul,\n.fpt-vacuum-layout ul,\n.fpt-install-grid ul,\n.fpt-choice-card ul,\n.fpt-contact-spec ul { margin: 0; padding: 0; list-style: none; }\n.fpt-two-panel li,\n.fpt-material-choice li,\n.fpt-vacuum-layout li,\n.fpt-install-grid li,\n.fpt-choice-card li,\n.fpt-contact-spec li { position: relative; padding: 4px 0 4px 15px; color: #6a7688; font-size: 10px; line-height: 1.5; }\n.fpt-two-panel li::before,\n.fpt-material-choice li::before,\n.fpt-vacuum-layout li::before,\n.fpt-install-grid li::before,\n.fpt-choice-card li::before,\n.fpt-contact-spec li::before { content: \"\"; position: absolute; top: 11px; left: 1px; width: 5px; height: 5px; border-radius: 50%; background: #58bec5; }\n.fpt-two-panel .is-ffkm { border-color: #cec1ed; background: #f5f1fc; }\n.fpt-two-panel .is-ffkm > span { color: #6b4ab9; }\n.fpt-two-panel .is-ffkm li::before { background: var(--purple); }\n.fpt-data-strip { display: grid; grid-template-columns: repeat(6,1fr); gap: 1px; margin: 28px 0; overflow: hidden; border: 1px solid #4d5a70; border-radius: 10px; background: #4d5a70; }\n.fpt-data-strip span { padding: 16px 8px; color: #cdd6e5; background: #172137; font-size: 8px; font-weight: 900; letter-spacing: .08em; text-align: center; }\n\n.fpt-temperature-stage { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; padding: 38px 35px; }\n.fpt-temperature-stage > div { padding: 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #fff; text-align: center; }\n.fpt-temperature-stage span,\n.fpt-temperature-stage small { display: block; }\n.fpt-temperature-stage span { font-size: 8px; font-weight: 900; letter-spacing: .12em; }\n.fpt-temperature-stage i { position: relative; display: block; width: 80%; height: 18px; margin: 35px auto 30px; border-radius: 999px; background: #e1e5ec; }\n.fpt-temperature-stage i::before { content: \"\"; position: absolute; inset: 0 auto 0 0; width: 75%; border-radius: inherit; }\n.fpt-temperature-stage i b { position: absolute; top: -28px; right: 11%; font-size: 16px; font-style: normal; }\n.fpt-temperature-stage small { color: #7d8899; font-size: 9px; }\n.fpt-temperature-stage .is-ptfe span,\n.fpt-temperature-stage .is-ptfe i b { color: #207b8e; }\n.fpt-temperature-stage .is-ptfe i::before { background: var(--cyan); }\n.fpt-temperature-stage .is-ffkm span,\n.fpt-temperature-stage .is-ffkm i b { color: #6849b7; }\n.fpt-temperature-stage .is-ffkm i::before { width: 92%; background: var(--purple); }\n\n.fpt-cryo-scale { position: relative; display: grid; grid-template-columns: 1.25fr auto 1fr auto 1fr; gap: 12px; align-items: center; margin: 31px 0; padding: 30px 24px 55px; border: 1px solid #dce3ec; border-radius: 14px; background: linear-gradient(90deg,#eafafd,#f3f5fb,#faf5fd); }\n.fpt-cryo-scale > div { min-height: 128px; padding: 20px 16px; border: 1px solid #d9e2ed; border-radius: 11px; background: #fff; }\n.fpt-cryo-scale > i { width: 20px; height: 2px; background: #9aa7b8; }\n.fpt-cryo-scale span,\n.fpt-cryo-scale b,\n.fpt-cryo-scale small { display: block; }\n.fpt-cryo-scale span { color: #54647b; font-size: 16px; font-weight: 900; }\n.fpt-cryo-scale b { margin-top: 12px; color: #3d4d63; font-size: 10px; }\n.fpt-cryo-scale small { margin-top: 5px; color: #7f8b9b; font-size: 8px; }\n.fpt-cryo-scale .is-extreme { border-color: #9adce2; background: #f1fcfd; }\n.fpt-cryo-scale .is-extreme span { color: #147f94; }\n.fpt-cryo-scale .is-special { border-color: #d6cbee; background: #f8f4fd; }\n.fpt-cryo-scale .is-special span { color: #7558b6; }\n.fpt-cryo-scale > em { position: absolute; right: 25px; bottom: 17px; color: #738093; font-size: 8px; font-style: normal; font-weight: 900; letter-spacing: .1em; }\n.fpt-application-chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 28px 0; }\n.fpt-application-chips span { padding: 8px 12px; border: 1px solid #cce4e8; border-radius: 999px; color: #27798a; background: #f0fafb; font-size: 9px; font-weight: 800; }\n\n.fpt-friction-compare { display: grid; grid-template-columns: 1fr auto 1fr; gap: 22px; align-items: center; margin: 31px 0; padding: 33px 28px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-friction-compare > div { padding: 22px; border: 1px solid #dbe2eb; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-friction-compare > em { color: #8c97a8; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-friction-compare span,\n.fpt-friction-compare b,\n.fpt-friction-compare small { display: block; }\n.fpt-friction-compare span { font-size: 9px; font-weight: 900; }\n.fpt-friction-compare i { display: block; width: 82%; height: 18px; margin: 29px auto; border-radius: 999px; }\n.fpt-friction-compare b { color: #425066; font-size: 12px; }\n.fpt-friction-compare small { margin-top: 5px; color: #7e899a; font-size: 9px; }\n.fpt-friction-compare .is-ffkm span { color: #6748b7; }\n.fpt-friction-compare .is-ffkm i { background: repeating-linear-gradient(90deg,#9d72f2 0 13px,#7451c3 14px 22px); }\n.fpt-friction-compare .is-ptfe span { color: #217b8d; }\n.fpt-friction-compare .is-ptfe i { height: 7px; background: linear-gradient(90deg,#9aeeee,var(--cyan)); }\n.fpt-application-grid { display: grid; grid-template-columns: repeat(5,1fr); gap: 8px; margin: 28px 0; }\n.fpt-application-grid > div { display: flex; gap: 10px; align-items: center; min-height: 67px; padding: 13px; border: 1px solid #dce3ec; border-radius: 10px; background: #f8f9fb; }\n.fpt-application-grid i { display: grid; flex: 0 0 28px; place-items: center; width: 28px; height: 28px; border-radius: 50%; color: #21798b; background: #e4f7f8; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-application-grid span { color: #526076; font-size: 9px; font-weight: 730; }\n\n.fpt-motion-map { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; gap: 12px; align-items: center; margin: 31px 0; }\n.fpt-motion-map > div { min-height: 130px; padding: 21px 18px; border: 1px solid #dce3ec; border-radius: 11px; background: #f8f9fb; }\n.fpt-motion-map > i { color: #919cad; font-style: normal; }\n.fpt-motion-map span,\n.fpt-motion-map b,\n.fpt-motion-map small { display: block; }\n.fpt-motion-map span { color: #65738a; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-motion-map b { margin-top: 16px; color: #38465c; font-size: 12px; }\n.fpt-motion-map small { margin-top: 5px; color: #7d889a; font-size: 9px; }\n.fpt-motion-map > div:first-child { border-color: #d1c4ed; background: #f6f2fc; }\n.fpt-motion-map > div:first-child span { color: #6a4bb8; }\n.fpt-motion-map > div:last-child { border-color: #c5e4e7; background: #effafb; }\n.fpt-motion-map > div:last-child span { color: #217c8d; }\n\n.fpt-spring-stage { display: grid; grid-template-columns: 1fr auto 1.08fr auto 1fr; gap: 14px; align-items: center; padding: 36px 31px; }\n.fpt-spring-stage > div { min-height: 195px; padding: 22px 17px; border: 1px solid #dce3ec; border-radius: 12px; background: #fff; text-align: center; }\n.fpt-spring-stage > em { color: #8e99aa; font-style: normal; }\n.fpt-spring-stage span,\n.fpt-spring-stage b,\n.fpt-spring-stage small { display: block; }\n.fpt-spring-stage span { color: #247b8c; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-spring-stage i { display: block; width: 100px; height: 47px; margin: 29px auto; background: repeating-linear-gradient(135deg,transparent 0 10px,#57cfd5 11px 15px,transparent 16px 25px); }\n.fpt-spring-stage i.is-light { opacity: .55; transform: scale(.85); }\n.fpt-spring-stage i.is-heavy { transform: scale(1.13); }\n.fpt-spring-stage b { color: #3e4d63; font-size: 12px; }\n.fpt-spring-stage small { margin-top: 5px; color: #7f8999; font-size: 9px; }\n.fpt-spring-stage .is-center { border-color: #556379; background: #172137; }\n.fpt-spring-stage .is-center span { color: var(--amber); }\n.fpt-spring-stage .is-center b { color: #f0f5ff; }\n.fpt-spring-stage .is-center small { color: #aeb9ca; }\n.fpt-material-choice { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 30px 0; }\n.fpt-material-choice > div { padding: 24px 23px; border: 1px solid #d1c4ed; border-radius: 13px; background: #f6f2fc; }\n.fpt-material-choice > div > span { color: #684ab6; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-material-choice ul { margin-top: 15px; }\n.fpt-material-choice li::before { background: var(--purple); }\n.fpt-material-choice .is-ptfe { border-color: #c3e1e5; background: #effafb; }\n.fpt-material-choice .is-ptfe > span { color: #217b8c; }\n.fpt-material-choice .is-ptfe li::before { background: var(--cyan); }\n\n.fpt-vacuum-layout { display: grid; grid-template-columns: 1fr .7fr 1fr; gap: 13px; align-items: stretch; margin: 31px 0; }\n.fpt-vacuum-layout > div { padding: 23px 21px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-vacuum-layout > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-vacuum-layout h3 { margin: 10px 0 13px; font-size: 17px; }\n.fpt-vacuum-layout .is-ffkm { border-color: #d2c5ed; background: #f6f2fc; }\n.fpt-vacuum-layout .is-ffkm > span { color: #6b4bb9; }\n.fpt-vacuum-layout .is-ffkm li::before { background: var(--purple); }\n.fpt-vacuum-layout .is-ptfe { border-color: #c7e3e6; background: #effafb; }\n.fpt-vacuum-layout .is-ptfe > span { color: #217c8d; }\n.fpt-vacuum-core { display: flex; flex-direction: column; align-items: center; justify-content: center; border-color: #4e5c74 !important; color: #edf5ff; background: #172137 !important; text-align: center; }\n.fpt-vacuum-core span { color: var(--amber); }\n.fpt-vacuum-core i { width: 86px; height: 86px; margin: 20px 0; border: 1px solid #66748b; border-radius: 50%; box-shadow: inset 0 0 0 15px #212e48,inset 0 0 0 16px #78859a; }\n.fpt-vacuum-core b { color: #dce5f3; font-size: 10px; }\n\n.fpt-pressure-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-pressure-compare > div { padding: 24px 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-pressure-compare > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-pressure-compare h3 { margin: 10px 0 8px; font-size: 18px; }\n.fpt-pressure-compare p { margin: 0 0 15px; font-size: 10px; line-height: 1.6; }\n.fpt-pressure-compare b { display: block; padding: 9px; border-radius: 7px; font-size: 8px; letter-spacing: .06em; text-align: center; }\n.fpt-pressure-compare .is-ffkm { border-color: #d1c3ee; background: #f6f2fc; }\n.fpt-pressure-compare .is-ffkm span { color: #6a4ab8; }\n.fpt-pressure-compare .is-ffkm b { color: #eadfff; background: #54398f; }\n.fpt-pressure-compare .is-ptfe { border-color: #c7e3e6; background: #effafb; }\n.fpt-pressure-compare .is-ptfe span { color: #217c8d; }\n.fpt-pressure-compare .is-ptfe b { color: #e2fcff; background: #176c7c; }\n.fpt-gap-stage { display: grid; grid-template-columns: 1.35fr .65fr; min-height: 310px; }\n.fpt-gap-stage > div { position: relative; overflow: hidden; border-right: 1px solid #dce3ec; background: #edf1f5; }\n.fpt-gap-stage > div > span { position: absolute; top: 30px; left: 30px; color: #9b4b3b; font-size: 9px; font-weight: 900; letter-spacing: .1em; }\n.fpt-gap-stage > div > em { position: absolute; top: 142px; left: 28px; color: #bd5e4d; font-size: 28px; font-style: normal; }\n.fpt-metal-top,\n.fpt-metal-bottom { position: absolute; right: 9%; left: 19%; height: 73px; border: 2px solid #85929d; background: linear-gradient(#bdc7ce,#667681); }\n.fpt-metal-top { top: 74px; }\n.fpt-metal-bottom { bottom: 59px; }\n.fpt-primary { position: absolute; z-index: 2; top: 119px; left: 42%; width: 105px; height: 105px; border: 27px solid var(--purple); border-radius: 50%; }\n.fpt-backup { position: absolute; z-index: 3; top: 125px; left: calc(42% + 78px); width: 29px; height: 92px; border-radius: 5px; background: var(--cyan); }\n.fpt-gap-stage > div > b { position: absolute; right: 5%; bottom: 17px; color: #5c697c; font-size: 8px; letter-spacing: .09em; }\n.fpt-gap-stage aside { padding: 36px 26px; background: #fff; }\n.fpt-gap-stage aside span { color: #227b8d; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-gap-stage aside p { margin: 17px 0 0; font-size: 10px; line-height: 1.62; }\n\n.fpt-semiconductor-map { display: grid; grid-template-columns: 1fr auto 1fr; gap: 17px; align-items: center; margin: 31px 0; padding: 27px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-semiconductor-map > div { min-height: 260px; padding: 23px; border: 1px solid #dce3ec; border-radius: 12px; background: #fff; }\n.fpt-semiconductor-map > i { color: #8995a7; font-size: 20px; font-style: normal; }\n.fpt-semiconductor-map span,\n.fpt-semiconductor-map b,\n.fpt-semiconductor-map small { display: block; }\n.fpt-semiconductor-map span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-semiconductor-map b { margin-top: 12px; padding-bottom: 7px; border-bottom: 1px solid #e2e6ed; color: #48556b; font-size: 10px; }\n.fpt-semiconductor-map small { margin-top: 16px; color: #7d8899; font-size: 9px; line-height: 1.5; }\n.fpt-semiconductor-map .is-ffkm { border-color: #d1c4ed; background: #f6f2fc; }\n.fpt-semiconductor-map .is-ffkm span { color: #694ab8; }\n.fpt-semiconductor-map .is-ptfe { border-color: #c6e2e6; background: #effafb; }\n.fpt-semiconductor-map .is-ptfe span { color: #217c8d; }\n\n.fpt-equipment-map { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; gap: 12px; align-items: center; margin: 31px 0; }\n.fpt-equipment-map > div { min-height: 135px; padding: 21px 18px; border: 1px solid #dce3ec; border-radius: 11px; background: #f8f9fb; }\n.fpt-equipment-map > div:nth-child(1) { border-color: #d2c5ed; background: #f6f2fc; }\n.fpt-equipment-map > div:nth-child(3) { border-color: #c8e3e7; background: #effafb; }\n.fpt-equipment-map > div:last-child { border-color: #526077; background: #172137; }\n.fpt-equipment-map > i { color: #909bad; font-style: normal; }\n.fpt-equipment-map span,\n.fpt-equipment-map b,\n.fpt-equipment-map small { display: block; }\n.fpt-equipment-map span { color: #667389; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-equipment-map b { margin-top: 16px; color: #39475e; font-size: 12px; }\n.fpt-equipment-map small { margin-top: 6px; color: #7e899b; font-size: 9px; line-height: 1.45; }\n.fpt-equipment-map > div:last-child span { color: var(--amber); }\n.fpt-equipment-map > div:last-child b { color: #f2f6ff; }\n.fpt-equipment-map > div:last-child small { color: #abb6c8; }\n.fpt-five-inputs { display: grid; grid-template-columns: repeat(5,1fr); gap: 1px; overflow: hidden; margin: 28px 0; border: 1px solid #505e74; border-radius: 10px; background: #505e74; }\n.fpt-five-inputs span { padding: 16px 8px; color: #ccd5e4; background: #172137; font-size: 8px; font-weight: 900; letter-spacing: .08em; text-align: center; }\n\n.fpt-deformation-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 31px 0; }\n.fpt-deformation-compare > div { min-height: 320px; padding: 25px 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; text-align: center; }\n.fpt-deformation-compare > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-deformation-compare i { display: block; width: 125px; height: 125px; margin: 27px auto; }\n.fpt-deformation-compare .is-ffkm { border-color: #d2c5ed; background: #f6f2fc; }\n.fpt-deformation-compare .is-ffkm > span { color: #6b4bb9; }\n.fpt-deformation-compare .is-ffkm i { height: 78px; margin-top: 51px; margin-bottom: 50px; border: 24px solid #805bd0; border-top-width: 16px; border-bottom-width: 16px; border-radius: 46%; }\n.fpt-deformation-compare .is-ptfe { border-color: #c7e3e6; background: #effafb; }\n.fpt-deformation-compare .is-ptfe > span { color: #217c8d; }\n.fpt-deformation-compare .is-ptfe i { border: 26px solid #53cbd1; border-radius: 50% 50% 36% 61%; transform: skewX(10deg); }\n.fpt-deformation-compare h3 { margin: 0 0 8px; font-size: 17px; }\n.fpt-deformation-compare p { margin: 0; font-size: 10px; line-height: 1.58; }\n.fpt-equation { display: flex; flex-wrap: wrap; gap: 9px; align-items: center; justify-content: center; margin: 30px 0; padding: 23px; border-radius: 13px; color: #eaf2ff; background: #172137; }\n.fpt-equation span { color: #9ba9bd; font-size: 8px; font-weight: 900; letter-spacing: .1em; }\n.fpt-equation b { padding: 8px 10px; border: 1px solid #55637a; border-radius: 6px; color: #e4ecf8; font-size: 9px; }\n.fpt-equation i { color: var(--amber); font-size: 8px; font-style: normal; font-weight: 900; }\n\n.fpt-install-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-install-grid > div { padding: 24px 23px; border: 1px solid #dce3ec; border-radius: 13px; background: #f8f9fb; }\n.fpt-install-grid > div > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-install-grid h3 { margin: 10px 0 13px; font-size: 18px; }\n.fpt-install-grid .is-ffkm { border-color: #d1c4ed; background: #f6f2fc; }\n.fpt-install-grid .is-ffkm > span { color: #6a4ab8; }\n.fpt-install-grid .is-ffkm li::before { background: var(--purple); }\n.fpt-install-grid .is-ptfe { border-color: #c6e3e6; background: #effafb; }\n.fpt-install-grid .is-ptfe > span { color: #217c8d; }\n.fpt-orientation-card { margin: 30px 0; padding: 24px; border: 1px solid #d9d19f; border-radius: 13px; background: #fffbef; }\n.fpt-orientation-card > span { color: #84671f; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-orientation-card > div { display: grid; grid-template-columns: 1fr auto 1.4fr auto 1fr; gap: 10px; align-items: center; margin-top: 18px; }\n.fpt-orientation-card b,\n.fpt-orientation-card em { padding: 12px; border: 1px solid #e5dcb8; border-radius: 8px; color: #62583f; background: #fff; font-size: 8px; font-style: normal; text-align: center; }\n.fpt-orientation-card i { color: #9c8b55; font-style: normal; }\n.fpt-orientation-card p { margin: 15px 0 0; color: #70664d; font-size: 10px; }\n\n.fpt-cost-equation { display: grid; grid-template-columns: repeat(9,auto); gap: 8px; align-items: center; margin: 31px 0; padding: 25px 20px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-cost-equation > div { min-height: 100px; padding: 16px 11px; border: 1px solid #dce2eb; border-radius: 9px; background: #fff; }\n.fpt-cost-equation > i { color: #919cad; font-style: normal; }\n.fpt-cost-equation span,\n.fpt-cost-equation b { display: block; }\n.fpt-cost-equation span { color: #6750a5; font-size: 7px; font-weight: 900; letter-spacing: .08em; }\n.fpt-cost-equation b { margin-top: 13px; color: #536076; font-size: 9px; line-height: 1.45; }\n.fpt-cost-equation > em { grid-column: 1\/-1; padding: 10px; border-radius: 7px; color: #dfe7f5; background: #172137; font-size: 9px; font-style: normal; font-weight: 900; letter-spacing: .1em; text-align: center; }\n\n.fpt-choice-card { display: grid; grid-template-columns: 1.25fr .75fr; gap: 13px; margin: 31px 0; padding: 27px; border: 1px solid #dce3ec; border-radius: 15px; }\n.fpt-choice-card > div { padding: 3px 4px; }\n.fpt-choice-card > div > span,\n.fpt-choice-card aside > span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-choice-card h3 { margin: 12px 0 15px; font-size: 22px; }\n.fpt-choice-card aside { padding: 20px; border-radius: 11px; }\n.fpt-choice-card aside b { display: block; margin-top: 10px; padding-bottom: 7px; border-bottom: 1px solid rgba(255,255,255,.12); font-size: 9px; }\n.fpt-choice-card.is-ffkm { border-color: #cfc0ed; background: #f6f2fc; }\n.fpt-choice-card.is-ffkm > div > span { color: #6c4abd; }\n.fpt-choice-card.is-ffkm li::before { background: var(--purple); }\n.fpt-choice-card.is-ffkm aside { color: #e9dfff; background: #51378b; }\n.fpt-choice-card.is-ffkm aside > span { color: #cfb6ff; }\n.fpt-choice-card.is-ptfe { border-color: #c3e3e6; background: #effafb; }\n.fpt-choice-card.is-ptfe > div > span { color: #207c8e; }\n.fpt-choice-card.is-ptfe aside { color: #dffcff; background: #176c7d; }\n.fpt-choice-card.is-ptfe aside > span { color: #9eeef0; }\n\n.fpt-spring-combination { display: grid; grid-template-columns: repeat(9,auto); gap: 8px; align-items: center; margin: 31px 0; padding: 25px 19px; border: 1px solid #dce3ec; border-radius: 14px; background: #f7f8fb; }\n.fpt-spring-combination > div { min-height: 85px; padding: 16px 10px; border: 1px solid #dce2eb; border-radius: 9px; background: #fff; }\n.fpt-spring-combination > div > span { color: #526075; font-size: 7px; font-weight: 900; letter-spacing: .07em; }\n.fpt-spring-combination > i { color: #919cad; font-style: normal; }\n.fpt-spring-combination > em { grid-column: 1\/-1; padding: 11px; border-radius: 7px; color: #e0fbff; background: #176c7d; font-size: 9px; font-style: normal; font-weight: 900; letter-spacing: .1em; text-align: center; }\n.fpt-label { display: inline-block; padding: 5px 8px; border-radius: 999px; font-size: 8px; letter-spacing: .04em; }\n.fpt-label.is-ffkm { color: #5e3daa; background: #eee6fc; }\n.fpt-label.is-ptfe { color: #176d7d; background: #e1f6f8; }\n.fpt-label.is-spring { color: #745d1e; background: #fff1c9; }\n\n.fpt-input-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 11px; margin: 31px 0; }\n.fpt-input-grid article { position: relative; min-height: 145px; padding: 23px 22px 20px 69px; border: 1px solid #dce3ec; border-radius: 12px; background: #f8f9fb; }\n.fpt-input-grid article > i { position: absolute; top: 23px; left: 21px; display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%; color: #6043aa; background: #eee8fa; font-size: 8px; font-style: normal; font-weight: 900; }\n.fpt-input-grid h3 { margin: 0 0 7px; font-size: 17px; }\n.fpt-input-grid p { margin: 0; font-size: 10px; line-height: 1.58; }\n.fpt-input-grid .is-motion { border-color: #4f5e74; background: #172137; }\n.fpt-input-grid .is-motion i { color: #15333a; background: var(--cyan); }\n.fpt-input-grid .is-motion h3 { color: #f2f6ff; }\n.fpt-input-grid .is-motion p { color: #acb7c9; }\n.fpt-inline-cta { display: grid; grid-template-columns: 1fr auto auto; gap: 14px; align-items: center; margin: 27px 0; padding: 19px 22px; border: 1px solid #53647e; border-radius: 11px; color: #eff5ff !important; background: #172137; transition: transform .2s ease,background .2s ease; }\n.fpt-inline-cta:hover { background: #202d49; transform: translateY(-2px); }\n.fpt-inline-cta span { color: #a8eff0; font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-inline-cta b { color: #eff5ff; font-size: 12px; }\n.fpt-inline-cta i { color: var(--amber); font-style: normal; }\n\n.fpt-mistake-list { display: grid; gap: 9px; margin: 30px 0; }\n.fpt-mistake-list article { display: grid; grid-template-columns: 48px 1fr; gap: 17px; align-items: center; padding: 17px 20px; border: 1px solid #dce3ec; border-radius: 11px; background: #f8f9fb; }\n.fpt-mistake-list article > span { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 50%; color: #a34d3c; background: #ffede8; font-size: 9px; font-weight: 900; }\n.fpt-mistake-list h3 { margin: 0 0 3px; font-size: 14px; }\n.fpt-mistake-list p { margin: 0; color: #707c8e; font-size: 10px; line-height: 1.5; }\n\n.fpt-summary-section { padding-bottom: 65px; }\n.fpt-summary-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 13px; margin: 31px 0; }\n.fpt-summary-pair > div { padding: 24px 23px; border: 1px solid #dce3ec; border-radius: 13px; }\n.fpt-summary-pair span,\n.fpt-summary-pair b { display: block; }\n.fpt-summary-pair span { font-size: 8px; font-weight: 900; letter-spacing: .13em; }\n.fpt-summary-pair b { margin-top: 12px; padding-bottom: 7px; border-bottom: 1px solid rgba(70,80,105,.12); color: #4c596e; font-size: 10px; }\n.fpt-summary-pair .is-ffkm { background: #f6f2fc; border-color: #d1c4ed; }\n.fpt-summary-pair .is-ffkm span { color: #6949b7; }\n.fpt-summary-pair .is-ptfe { background: #effafb; border-color: #c6e3e6; }\n.fpt-summary-pair .is-ptfe span { color: #217b8d; }\n.fpt-summary-inputs { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; justify-content: center; margin: 31px 0; padding: 25px; border-radius: 14px; background: #172137; }\n.fpt-summary-inputs span { padding: 7px 9px; border: 1px solid #526078; border-radius: 6px; color: #c0cbdb; font-size: 8px; font-weight: 900; }\n.fpt-summary-inputs i { color: #7b899f; font-size: 9px; font-style: normal; }\n.fpt-summary-inputs b { padding: 8px 11px; border-radius: 6px; color: #143039; background: var(--cyan); font-size: 9px; }\n\n.fpt-faq-list { margin: 31px 0; border-top: 1px solid #dce3ec; }\n.fpt-faq-item { border-bottom: 1px solid #dce3ec; }\n.fpt-faq-item > button { display: grid; grid-template-columns: 1fr 24px; gap: 18px; align-items: center; width: 100%; padding: 20px 4px; border: 0; color: #25344d; background: transparent; text-align: left; cursor: pointer; }\n.fpt-faq-item > button span { font-size: 14px; font-weight: 780; }\n.fpt-faq-item > button i { position: relative; width: 20px; height: 20px; border: 1px solid #c2cad9; border-radius: 50%; }\n.fpt-faq-item > button i::before,\n.fpt-faq-item > button i::after { content: \"\"; position: absolute; top: 9px; left: 5px; width: 8px; height: 1px; background: #6648b4; transition: transform .2s ease; }\n.fpt-faq-item > button i::after { transform: rotate(90deg); }\n.fpt-faq-item > button[aria-expanded=\"true\"] i::after { transform: rotate(0); }\n.fpt-faq-answer { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .28s ease; }\n.fpt-faq-answer > p { min-height: 0; margin: 0; overflow: hidden; color: #647084; font-size: 12px; line-height: 1.7; }\n.fpt-faq-item.is-open .fpt-faq-answer { grid-template-rows: 1fr; }\n.fpt-faq-item.is-open .fpt-faq-answer > p { padding: 0 42px 20px 4px; }\n\n.fpt-contact { margin-top: 78px; padding: 54px; border-radius: 20px; color: #eff5ff; background: radial-gradient(circle at 100% 0,rgba(81,212,218,.2),transparent 43%),radial-gradient(circle at 0 100%,rgba(157,114,242,.16),transparent 46%),#151f33; box-shadow: 0 30px 72px rgba(17,28,52,.2); scroll-margin-top: 100px; }\n.fpt-contact-grid { display: grid; grid-template-columns: 1.18fr .82fr; gap: 50px; align-items: center; }\n.fpt-contact .fpt-eyebrow { margin-bottom: 13px; }\n.fpt-contact h2 { margin: 0 0 17px; color: #f5f8ff; font-size: clamp(32px,4vw,50px); line-height: 1.06; letter-spacing: -.04em; }\n.fpt-contact p { margin-bottom: 25px; color: #abb7ca; font-size: 13px; line-height: 1.65; }\n.fpt-button.is-light { color: #122a31 !important; background: linear-gradient(135deg,#acf5f4,var(--cyan)); }\n.fpt-button.is-light i { margin-left: 12px; font-style: normal; }\n.fpt-contact-spec { padding: 24px; border: 1px solid #53627a; border-radius: 13px; background: rgba(255,255,255,.035); }\n.fpt-contact-spec > span { color: var(--amber); font-size: 8px; font-weight: 900; letter-spacing: .14em; }\n.fpt-contact-spec li { color: #bdc8d9; }\n.fpt-contact-spec li::before { background: var(--cyan); }\n.fpt-back-top { position: fixed; z-index: 80; right: 24px; bottom: 24px; display: grid; place-items: center; width: 44px; height: 44px; border: 1px solid #56657d; border-radius: 50%; color: #eff5ff; background: #172137; box-shadow: 0 12px 30px rgba(16,27,52,.22); opacity: 0; visibility: hidden; transform: translateY(12px); cursor: pointer; transition: opacity .2s ease,visibility .2s ease,transform .2s ease,background .2s ease; }\n.fpt-back-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0); }\n.fpt-back-top:hover { background: #22304d; }\n\n@media (max-width: 1180px) {\n .fpt-hero-inner { grid-template-columns: 1fr .86fr; width: min(1120px,calc(100% - 48px)); }\n .fpt-hero h1 { font-size: clamp(42px,5vw,64px); }\n .fpt-content-shell { grid-template-columns: 250px minmax(0,1fr); gap: 50px; width: min(1100px,calc(100% - 48px)); }\n .fpt-selector-body { grid-template-columns: .62fr .95fr 1.05fr; }\n}\n\n@media (max-width: 900px) {\n .fpt-hero { min-height: auto; }\n .fpt-hero-inner { grid-template-columns: 1fr; min-height: auto; padding: 78px 0 70px; }\n .fpt-hero-copy { max-width: 790px; }\n .fpt-hero-visual { width: min(100%,650px); justify-self: center; }\n .fpt-content-shell { display: block; width: min(790px,calc(100% - 40px)); padding-top: 42px; }\n .fpt-sidebar { margin-bottom: 36px; }\n .fpt-sidebar-card,\n .fpt-sidebar-card.is-fixed,\n .fpt-sidebar-card.is-bottom { position: relative; top: auto; right: auto; bottom: auto; left: auto; width: 100%; max-height: none; }\n .fpt-sidebar-title > span { display: none; }\n .fpt-sidebar-title button { display: flex; width: 100%; align-items: center; justify-content: space-between; }\n .fpt-toc { display: none; max-height: 55vh; }\n .fpt-sidebar-card.is-open .fpt-toc { display: block; }\n .fpt-sidebar-note { display: 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column; }\n .fpt-button { width: 100%; }\n .fpt-metrics div { padding-right: 10px; }\n .fpt-metrics div + div { padding-left: 10px; }\n .fpt-metrics strong { font-size: 21px; }\n .fpt-visual-label { top: 5px; left: 7px; }\n .fpt-hero-visual figcaption { margin-top: 0; text-align: center; }\n .fpt-content-shell { width: calc(100% - 28px); padding-bottom: 75px; }\n .fpt-section { padding-top: 58px; }\n .fpt-section-heading { grid-template-columns: 40px 1fr; gap: 13px; }\n .fpt-section-index { width: 40px; height: 40px; }\n .fpt-section h2 { font-size: 31px; }\n .fpt-intro > p:first-of-type { font-size: 18px; }\n .fpt-article blockquote { padding: 21px 20px 21px 26px; }\n .fpt-article blockquote p { font-size: 16px; }\n .fpt-principle-chain,\n .fpt-evidence-grid,\n .fpt-mechanism-compare,\n .fpt-two-panel,\n .fpt-temperature-stage,\n .fpt-material-choice,\n .fpt-pressure-compare,\n .fpt-semiconductor-map,\n .fpt-deformation-compare,\n .fpt-install-grid,\n .fpt-choice-card,\n .fpt-input-grid,\n .fpt-summary-pair,\n .fpt-contact-grid { grid-template-columns: 1fr; }\n .fpt-selector-head { align-items: flex-start; flex-direction: column; }\n .fpt-selector-body { display: block; }\n .fpt-selector-controls { display: grid; grid-template-columns: repeat(2,1fr); }\n .fpt-selector-stage { min-height: 350px; border-right: 0; border-bottom: 1px solid rgba(190,202,228,.15); }\n .fpt-selector-result { min-height: 300px; }\n .fpt-visual-head { align-items: flex-start; flex-direction: column; gap: 5px; }\n .fpt-visual-head strong { text-align: left; }\n .fpt-recovery-stage,\n .fpt-spring-stage { grid-template-columns: 1fr; padding: 24px 19px; }\n .fpt-recovery-stage > em,\n .fpt-spring-stage > em { transform: rotate(90deg); }\n .fpt-ptfe-stage { grid-template-columns: 1fr; padding: 24px 19px; }\n .fpt-chemical-path,\n .fpt-motion-map,\n .fpt-equipment-map { grid-template-columns: 1fr; }\n .fpt-chemical-path > i,\n .fpt-motion-map > i,\n .fpt-equipment-map > i { text-align: center; transform: rotate(90deg); }\n .fpt-data-strip,\n .fpt-five-inputs { grid-template-columns: 1fr; }\n .fpt-cryo-scale { grid-template-columns: 1fr; padding-bottom: 55px; }\n .fpt-cryo-scale > i { width: 2px; height: 18px; margin: 0 auto; }\n .fpt-friction-compare { grid-template-columns: 1fr; }\n .fpt-friction-compare > em { text-align: center; transform: rotate(90deg); }\n .fpt-application-grid { grid-template-columns: repeat(2,1fr); }\n .fpt-vacuum-layout { grid-template-columns: 1fr; }\n .fpt-gap-stage { grid-template-columns: 1fr; }\n .fpt-gap-stage > div { min-height: 300px; border-right: 0; border-bottom: 1px solid #dce3ec; }\n .fpt-semiconductor-map > i { text-align: center; }\n .fpt-orientation-card > div { grid-template-columns: 1fr; }\n .fpt-orientation-card i { text-align: center; transform: rotate(90deg); }\n .fpt-cost-equation,\n .fpt-spring-combination { grid-template-columns: 1fr; }\n .fpt-cost-equation > em,\n .fpt-spring-combination > em { grid-column: auto; }\n .fpt-spring-combination > i { text-align: center; }\n .fpt-inline-cta { grid-template-columns: 1fr auto; }\n .fpt-inline-cta span { grid-column: span 2; }\n .fpt-contact { margin-top: 55px; padding: 30px 23px; border-radius: 16px; }\n .fpt-contact h2 { font-size: 35px; }\n .fpt-back-top { right: 15px; bottom: 15px; }\n}\n\n@media (prefers-reduced-motion: reduce) {\n .fpt-page *,\n .fpt-page *::before,\n .fpt-page *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }\n}\n <\/style>\n<\/head>\n<body>\n<div class=\"fpt-page\" id=\"fpt-top\" data-fpt-page>\n <div class=\"fpt-reading-progress\" aria-hidden=\"true\"><span data-fpt-progress><\/span><\/div>\n\n <header class=\"fpt-hero\">\n <div class=\"fpt-hero-grid\" aria-hidden=\"true\"><\/div>\n <div class=\"fpt-hero-glow fpt-glow-one\" aria-hidden=\"true\"><\/div>\n <div class=\"fpt-hero-glow fpt-glow-two\" aria-hidden=\"true\"><\/div>\n <div class=\"fpt-hero-inner\">\n <div class=\"fpt-hero-copy\">\n <div class=\"fpt-breadcrumb\"><span>Walle Seals<\/span><i><\/i><span>Materials & Compatibility<\/span><\/div>\n <div class=\"fpt-eyebrow\"><b><\/b>ELASTOMER vs FLUOROPOLYMER<\/div>\n <h1>FFKM vs PTFE Seals: Which Material Is Right for Your Application?<\/h1>\n <p class=\"fpt-hero-deck\">Compare how elasticity, creep, friction, temperature, pressure, vacuum and motion change the correct choice between an FFKM O-ring and an engineered PTFE seal.<\/p>\n <div class=\"fpt-hero-actions\">\n <a class=\"fpt-button fpt-button-primary\" href=\"#fpt-overview\">Compare the materials <b>\u2193<\/b><\/a>\n <a class=\"fpt-button fpt-button-ghost\" href=\"#fpt-selection\">Open the selection guide<\/a>\n <\/div>\n <div class=\"fpt-metrics\" aria-label=\"Guide overview\"><div><strong>2<\/strong><span>material behaviors<\/span><\/div><div><strong>6<\/strong><span>service scenarios<\/span><\/div><div><strong>12<\/strong><span>selection rows<\/span><\/div><\/div>\n <\/div>\n\n <figure class=\"fpt-hero-visual\" aria-label=\"FFKM O-ring and spring energized PTFE seal comparison\">\n <div class=\"fpt-visual-label\"><span>SEALING FORCE<\/span><b>RECOVERY vs ENERGIZATION<\/b><\/div>\n <svg viewBox=\"0 0 720 620\" role=\"img\" aria-labelledby=\"fpt-hero-title fpt-hero-desc\">\n <title id=\"fpt-hero-title\">FFKM and PTFE sealing mechanisms<\/title>\n <desc id=\"fpt-hero-desc\">A split technical illustration comparing an elastomeric FFKM O-ring with a spring energized PTFE lip seal.<\/desc>\n <defs>\n <linearGradient id=\"fpt-ffkm-gradient\" x1=\"0\" y1=\"0\" x2=\"1\" y2=\"1\"><stop offset=\"0\" stop-color=\"#c899ff\"\/><stop offset=\".55\" stop-color=\"#7651ce\"\/><stop offset=\"1\" stop-color=\"#392270\"\/><\/linearGradient>\n <linearGradient id=\"fpt-ptfe-gradient\" x1=\"0\" y1=\"0\" x2=\"1\" y2=\"1\"><stop offset=\"0\" stop-color=\"#efffff\"\/><stop offset=\".45\" stop-color=\"#8fe8ea\"\/><stop offset=\"1\" stop-color=\"#278da0\"\/><\/linearGradient>\n <linearGradient id=\"fpt-metal-gradient\" x1=\"0\" y1=\"0\" x2=\"0\" y2=\"1\"><stop offset=\"0\" stop-color=\"#abc0ca\"\/><stop offset=\"1\" stop-color=\"#465b66\"\/><\/linearGradient>\n <filter id=\"fpt-shadow\" x=\"-40%\" y=\"-40%\" width=\"180%\" height=\"180%\"><feDropShadow dx=\"0\" dy=\"20\" stdDeviation=\"20\" flood-color=\"#000\" flood-opacity=\".4\"\/><\/filter>\n <filter id=\"fpt-glow\" x=\"-180%\" y=\"-180%\" width=\"360%\" height=\"360%\"><feGaussianBlur stdDeviation=\"5\" result=\"b\"\/><feMerge><feMergeNode in=\"b\"\/><feMergeNode in=\"SourceGraphic\"\/><\/feMerge><\/filter>\n <\/defs>\n <g opacity=\".26\" stroke=\"#52657a\" fill=\"none\"><path d=\"M48 118H672M48 208H672M48 298H672M48 388H672M48 478H672\" stroke-dasharray=\"3 11\"\/><path d=\"M105 70V545M225 70V545M345 70V545M465 70V545M585 70V545\" stroke-dasharray=\"3 11\"\/><\/g>\n <path d=\"M360 78V540\" stroke=\"#526478\" stroke-dasharray=\"4 9\" opacity=\".55\"\/>\n <g filter=\"url(#fpt-shadow)\">\n <rect x=\"66\" y=\"196\" width=\"254\" height=\"238\" rx=\"23\" fill=\"#17202d\" stroke=\"#65738a\"\/>\n <rect x=\"400\" y=\"196\" width=\"254\" height=\"238\" rx=\"23\" fill=\"#14242c\" stroke=\"#527b85\"\/>\n <rect x=\"93\" y=\"226\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <rect x=\"93\" y=\"355\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <ellipse cx=\"193\" cy=\"315\" rx=\"74\" ry=\"74\" fill=\"none\" stroke=\"url(#fpt-ffkm-gradient)\" stroke-width=\"39\"\/>\n <rect x=\"427\" y=\"226\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <rect x=\"427\" y=\"355\" width=\"200\" height=\"49\" rx=\"6\" fill=\"url(#fpt-metal-gradient)\"\/>\n <path d=\"M463 275h43v67c0 16-13 29-29 29h-14zM591 275h-43v67c0 16 13 29 29 29h14z\" fill=\"url(#fpt-ptfe-gradient)\" stroke=\"#dffcff\"\/>\n <path d=\"M506 317l11-17 10 17 11-17 10 17\" fill=\"none\" stroke=\"#ffcb68\" stroke-width=\"8\" stroke-linejoin=\"round\" filter=\"url(#fpt-glow)\"\/>\n <\/g>\n <g font-family=\"Arial, sans-serif\"><text x=\"193\" y=\"161\" fill=\"#d9bdff\" text-anchor=\"middle\" font-size=\"13\" font-weight=\"700\">FFKM O-RING<\/text><text x=\"193\" y=\"179\" fill=\"#8492a4\" text-anchor=\"middle\" font-size=\"9\">natural elastic recovery<\/text><text x=\"527\" y=\"161\" fill=\"#a9f5f4\" text-anchor=\"middle\" font-size=\"13\" font-weight=\"700\">PTFE LIP SEAL<\/text><text x=\"527\" y=\"179\" fill=\"#8492a4\" text-anchor=\"middle\" font-size=\"9\">spring + geometry<\/text><path d=\"M193 292v-52\" stroke=\"#c498ff\" stroke-width=\"3\"\/><path d=\"M193 338v52\" stroke=\"#c498ff\" stroke-width=\"3\"\/><path d=\"M471 305l-26-31M583 305l26-31\" stroke=\"#7ce4e6\" stroke-width=\"3\"\/><text x=\"193\" y=\"483\" fill=\"#c7a7f5\" text-anchor=\"middle\" font-size=\"10\" font-weight=\"700\">SQUEEZE \u2192 RECOVERY<\/text><text x=\"527\" y=\"483\" fill=\"#87e4e5\" text-anchor=\"middle\" font-size=\"10\" font-weight=\"700\">SPRING \u2192 LIP CONTACT<\/text><\/g>\n <g transform=\"translate(240 520)\"><rect width=\"240\" height=\"48\" rx=\"10\" fill=\"#0a111b\" stroke=\"#566477\"\/><text x=\"120\" y=\"20\" fill=\"#8291a2\" text-anchor=\"middle\" font-family=\"Arial\" font-size=\"8\" letter-spacing=\"1.4\">SAME CHEMICAL RESISTANCE CLASS<\/text><text x=\"120\" y=\"36\" fill=\"#eff8ff\" text-anchor=\"middle\" font-family=\"Arial\" font-size=\"12\" font-weight=\"700\">DIFFERENT MECHANICAL BEHAVIOR<\/text><\/g>\n <\/svg>\n <figcaption><span><\/span>The sealing mechanism\u2014not only the material name\u2014drives the design.<\/figcaption>\n <\/figure>\n <\/div>\n <\/header>\n\n <div class=\"fpt-content-shell\" data-fpt-shell>\n <aside class=\"fpt-sidebar\" data-fpt-sidebar>\n <div class=\"fpt-sidebar-card\" data-fpt-sidebar-card>\n <div class=\"fpt-sidebar-title\"><span>On this page<\/span><button type=\"button\" data-fpt-toc-toggle aria-expanded=\"false\">Contents <b>+<\/b><\/button><\/div>\n <nav class=\"fpt-toc\" data-fpt-toc aria-label=\"Article contents\">\n <a href=\"#fpt-overview\"><span>00<\/span><em>At a Glance<\/em><\/a>\n <a href=\"#fpt-ffkm\"><span>01<\/span><em>What Is FFKM?<\/em><\/a>\n <a href=\"#fpt-ptfe\"><span>02<\/span><em>What Is PTFE?<\/em><\/a>\n <a href=\"#fpt-elasticity\"><span>03<\/span><em>Fundamental Difference<\/em><\/a>\n <a href=\"#fpt-chemical\"><span>04<\/span><em>Chemical Resistance<\/em><\/a>\n <a href=\"#fpt-high-temp\"><span>05<\/span><em>High Temperature<\/em><\/a>\n <a href=\"#fpt-low-temp\"><span>06<\/span><em>Low Temperature<\/em><\/a>\n <a href=\"#fpt-friction\"><span>07<\/span><em>Friction<\/em><\/a>\n <a href=\"#fpt-dynamic\"><span>08<\/span><em>Dynamic Sealing<\/em><\/a>\n <a href=\"#fpt-spring\"><span>09<\/span><em>Spring Energized PTFE<\/em><\/a>\n <a href=\"#fpt-vacuum\"><span>10<\/span><em>Vacuum Applications<\/em><\/a>\n <a href=\"#fpt-pressure\"><span>11<\/span><em>Pressure & Extrusion<\/em><\/a>\n <a href=\"#fpt-semiconductor\"><span>12<\/span><em>Semiconductor Equipment<\/em><\/a>\n <a href=\"#fpt-pumps\"><span>13<\/span><em>Chemical Pumps & Valves<\/em><\/a>\n <a href=\"#fpt-deformation\"><span>14<\/span><em>Compression Set vs Creep<\/em><\/a>\n <a href=\"#fpt-installation\"><span>15<\/span><em>Installation Differences<\/em><\/a>\n <a href=\"#fpt-cost\"><span>16<\/span><em>Total Cost<\/em><\/a>\n <a href=\"#fpt-choose-ffkm\"><span>17<\/span><em>Choose FFKM<\/em><\/a>\n <a href=\"#fpt-choose-ptfe\"><span>18<\/span><em>Choose PTFE<\/em><\/a>\n <a href=\"#fpt-choose-spring\"><span>19<\/span><em>Choose Spring Energized<\/em><\/a>\n <a href=\"#fpt-selection\"><span>20<\/span><em>Practical Selection Table<\/em><\/a>\n <a href=\"#fpt-information\"><span>21<\/span><em>Information Required<\/em><\/a>\n <a href=\"#fpt-mistakes\"><span>22<\/span><em>Selection Mistakes<\/em><\/a>\n <a href=\"#fpt-summary\"><span>23<\/span><em>Engineering Summary<\/em><\/a>\n <a href=\"#fpt-faq\"><span>24<\/span><em>Frequently Asked Questions<\/em><\/a>\n <a href=\"#fpt-contact\"><span>25<\/span><em>Custom Seal Review<\/em><\/a>\n <\/nav>\n <div class=\"fpt-sidebar-note\"><span>CORE DIFFERENCE<\/span><p>FFKM supplies elastic recovery. PTFE supplies low friction and chemical inertness, often with engineered energization.<\/p><\/div>\n <\/div>\n <\/aside>\n\n <main class=\"fpt-main\">\n <article class=\"fpt-article\" data-fpt-article>\n <section class=\"fpt-intro\">\n <div class=\"fpt-tags\"><span>FFKM Seals<\/span><span>PTFE Seals<\/span><span>Spring Energized<\/span><span>Material Selection<\/span><\/div>\n <p>FFKM and PTFE are both highly fluorinated materials used with aggressive chemicals, high temperatures, vacuum, semiconductor processes, pharmaceutical equipment, pumps, valves and aerospace systems.<\/p>\n <p>The similarity ends at chemical resistance. FFKM is a perfluoroelastomer with rubber-like recovery. PTFE is a fluoropolymer with extremely low friction, limited natural elasticity and a tendency to creep under sustained load.<\/p>\n <blockquote><p><strong>Choose FFKM for elastomeric recovery and conventional O-ring sealing. Choose PTFE when low friction, dry running, cryogenic capability or engineered dynamic performance matters more.<\/strong><\/p><\/blockquote>\n <div class=\"fpt-principle-chain\"><div><span>FFKM<\/span><b>Squeeze<\/b><small>Elastic recovery<\/small><\/div><i>vs<\/i><div><span>PTFE<\/span><b>Lip geometry<\/b><small>Spring or pressure load<\/small><\/div><i>\u2192<\/i><div class=\"is-result\"><span>DECISION<\/span><b>Match the mechanism<\/b><small>Chemistry + motion + temperature<\/small><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-overview\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">00<\/span><div><p>FAST COMPARISON<\/p><h2>FFKM vs PTFE at a Glance<\/h2><\/div><\/div>\n <p>Use the interactive screen to identify the design direction, then verify the exact compound, hardware and duty cycle.<\/p>\n <div class=\"fpt-selector is-static\" data-fpt-selector>\n <div class=\"fpt-selector-head\"><div><span>APPLICATION SCREENING TOOL<\/span><h3>Select the dominant requirement<\/h3><\/div><strong data-fpt-selector-status>Static extreme-chemical seal<\/strong><\/div>\n <div class=\"fpt-selector-body\">\n <div class=\"fpt-selector-controls\" role=\"group\" aria-label=\"Seal application requirements\">\n <button class=\"is-active\" type=\"button\" data-fpt-case=\"static\" aria-pressed=\"true\"><i>01<\/i><span>Static \/ O-ring<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"recip\" aria-pressed=\"false\"><i>02<\/i><span>Reciprocating<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"rotary\" aria-pressed=\"false\"><i>03<\/i><span>Rotary<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"cryo\" aria-pressed=\"false\"><i>04<\/i><span>Cryogenic<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"vacuum\" aria-pressed=\"false\"><i>05<\/i><span>Vacuum<\/span><\/button>\n <button type=\"button\" data-fpt-case=\"heat\" aria-pressed=\"false\"><i>06<\/i><span>Extreme heat<\/span><\/button>\n <\/div>\n <div class=\"fpt-selector-stage\" aria-hidden=\"true\"><div class=\"fpt-scale\"><span>ELASTIC RECOVERY<\/span><i><\/i><span>LOW FRICTION<\/span><\/div><div class=\"fpt-choice is-ffkm\"><b>FFKM<\/b><small>ELASTOMER<\/small><\/div><div class=\"fpt-choice is-ptfe\"><b>PTFE<\/b><small>FLUOROPOLYMER<\/small><\/div><div class=\"fpt-choice is-spring\"><b>SPRING<\/b><small>ENERGIZED PTFE<\/small><\/div><\/div>\n <div class=\"fpt-selector-result\" aria-live=\"polite\"><span data-fpt-result-kicker>USUALLY CONSIDER FIRST: FFKM<\/span><h3 data-fpt-result-title>Use natural recovery in a conventional O-ring gland.<\/h3><p data-fpt-result-copy>For static sealing with aggressive chemistry and high temperature, FFKM provides contact force without a separate energizer.<\/p><div><b>VERIFY<\/b><p data-fpt-result-check>Exact chemistry \u00b7 temperature \u00b7 compression set \u00b7 groove fill<\/p><\/div><a href=\"#fpt-choose-ffkm\" data-fpt-result-link>Open the FFKM decision section \u2192<\/a><\/div>\n <\/div>\n <p class=\"fpt-tool-note\">Initial screening only. Final design depends on the exact compound, seal profile, gland, counterface and operating cycle.<\/p>\n <\/div>\n <div class=\"fpt-table-wrap\" role=\"region\" aria-label=\"FFKM and PTFE overview\" tabindex=\"0\"><table><thead><tr><th>Property<\/th><th>FFKM<\/th><th>PTFE<\/th><\/tr><\/thead><tbody>\n <tr><td>Material family<\/td><td>Perfluoroelastomer<\/td><td>Fluoropolymer<\/td><\/tr><tr><td>Material behavior<\/td><td>Elastic \/ rubber-like<\/td><td>Plastic \/ non-elastomeric<\/td><\/tr><tr><td>Chemical resistance<\/td><td>Exceptional<\/td><td>Exceptional<\/td><\/tr><tr><td>Natural elastic recovery<\/td><td>Excellent<\/td><td>Limited<\/td><\/tr><tr><td>Friction<\/td><td>Moderate<\/td><td>Extremely low<\/td><\/tr><tr><td>Standard O-ring sealing<\/td><td>Excellent<\/td><td>Specialized<\/td><\/tr><tr><td>Dynamic sealing<\/td><td>Application-dependent<\/td><td>Excellent with correct design<\/td><\/tr><tr><td>Dry running<\/td><td>Limited by design<\/td><td>Excellent<\/td><\/tr><tr><td>Long-load concern<\/td><td>Compression set<\/td><td>Creep \/ deformation<\/td><\/tr><tr><td>Cryogenic capability<\/td><td>Compound-dependent<\/td><td>Excellent with correct design<\/td><\/tr><tr><td>Typical products<\/td><td>O-rings, gaskets, molded parts<\/td><td>Lip seals, energized seals, backups, gaskets<\/td><\/tr><tr><td>Energizer<\/td><td>Normally unnecessary<\/td><td>Common in demanding service<\/td><\/tr>\n <\/tbody><\/table><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-ffkm\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">01<\/span><div><p>PERFLUOROELASTOMER<\/p><h2>What Is FFKM?<\/h2><\/div><\/div>\n <p>FFKM is the ASTM designation for perfluoroelastomers engineered to combine rubber-like elasticity, broad chemical resistance and high-temperature stability.<\/p>\n <figure class=\"fpt-visual fpt-ffkm-visual\"><div class=\"fpt-visual-head\"><span>ELASTOMERIC FORCE<\/span><strong>Compression creates recoverable contact pressure<\/strong><\/div><div class=\"fpt-recovery-stage\"><div><span>FREE STATE<\/span><i><\/i><b>Original cross-section<\/b><\/div><em>COMPRESS<\/em><div class=\"is-loaded\"><span>INSTALLED<\/span><i><\/i><b>Recovery pushes outward<\/b><\/div><em>PRESSURE<\/em><div class=\"is-energized\"><span>IN SERVICE<\/span><i><\/i><b>System pressure adds load<\/b><\/div><\/div><figcaption>An FFKM O-ring normally needs no separate metallic spring.<\/figcaption><\/figure>\n <div class=\"fpt-chip-grid\"><span>O-rings<\/span><span>Gaskets<\/span><span>Valve seals<\/span><span>Mechanical seal secondary seals<\/span><span>Custom molded seals<\/span><span>Bonded components<\/span><\/div>\n <div class=\"fpt-evidence-grid\"><div><span>CHEMISTRY<\/span><h3>Grade-specific<\/h3><p>General service, acids, amines, steam and plasma can require different formulations.<\/p><\/div><div><span>PURITY<\/span><h3>Process-specific<\/h3><p>Semiconductor grades may target particles, outgassing and metal-ion contamination.<\/p><\/div><div class=\"is-dark\"><span>MECHANICS<\/span><h3>Elastic sealing<\/h3><p>Recovery, squeeze, compression set and extrusion resistance define performance.<\/p><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-ptfe\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">02<\/span><div><p>FLUOROPOLYMER<\/p><h2>What Is PTFE?<\/h2><\/div><\/div>\n <p>PTFE is a fluoropolymer with exceptional chemical resistance, extremely low friction, wide temperature capability, non-stick behavior and strong dry-running performance. It does not recover like rubber.<\/p>\n <figure class=\"fpt-visual fpt-ptfe-visual\"><div class=\"fpt-visual-head\"><span>ENGINEERED CONTACT<\/span><strong>Geometry and energization compensate for limited elastic memory<\/strong><\/div><div class=\"fpt-ptfe-stage\"><div><span>PTFE JACKET<\/span><i class=\"fpt-jacket-left\"><\/i><i class=\"fpt-jacket-right\"><\/i><b>Low-friction sealing lips<\/b><\/div><div class=\"fpt-spring-core\"><span>METAL SPRING<\/span><i><\/i><b>Continuous outward force<\/b><\/div><div><span>HARDWARE<\/span><i class=\"fpt-hardware-top\"><\/i><i class=\"fpt-hardware-bottom\"><\/i><b>Controlled mating surfaces<\/b><\/div><\/div><figcaption>PTFE seals may also use an elastomer energizer, specialized lip geometry or pressure energization.<\/figcaption><\/figure>\n <div class=\"fpt-chip-grid is-cyan\"><span>Spring energized seals<\/span><span>Rotary seals<\/span><span>Piston seals<\/span><span>Rod seals<\/span><span>Valve seats<\/span><span>Backup rings<\/span><span>Gaskets<\/span><span>PTFE O-rings<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-elasticity\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">03<\/span><div><p>HOW CONTACT FORCE IS CREATED<\/p><h2>The Fundamental Difference: Elasticity<\/h2><\/div><\/div>\n <div class=\"fpt-mechanism-compare\"><div class=\"is-ffkm\"><span>FFKM<\/span><h3>Elastic memory<\/h3><ol><li>Seal is compressed<\/li><li>Elastomer tries to recover<\/li><li>Contact pressure forms<\/li><li>System pressure adds energization<\/li><\/ol><b>NO EXTRA SPRING NORMALLY REQUIRED<\/b><\/div><div class=\"is-ptfe\"><span>PTFE<\/span><h3>Engineered energization<\/h3><ol><li>Jacket or lip is installed<\/li><li>Spring or pressure supplies load<\/li><li>Lips contact the hardware<\/li><li>Geometry manages wear and leakage<\/li><\/ol><b>ENERGIZER COMMON IN DEMANDING DUTY<\/b><\/div><\/div>\n <blockquote><p>FFKM design centers on elastic recovery and compression set. PTFE design centers on creep, lip geometry and how sealing force is maintained.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-chemical\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">04<\/span><div><p>BASE POLYMER \u2260 COMPLETE COMPOUND<\/p><h2>FFKM vs PTFE Chemical Resistance<\/h2><\/div><\/div>\n <p>Both materials cover an exceptionally broad chemical range, so the correct question is not simply \u201cwhich is more resistant?\u201d It is whether the exact FFKM formulation or PTFE compound is compatible with the complete service mixture.<\/p>\n <div class=\"fpt-chemical-path\"><div><span>BASE MATERIAL<\/span><b>FFKM or virgin PTFE<\/b><\/div><i>+<\/i><div><span>FORMULATION<\/span><b>Cure system or fillers<\/b><\/div><i>+<\/i><div><span>ENVIRONMENT<\/span><b>Chemistry + heat + time<\/b><\/div><i>\u2192<\/i><div class=\"is-result\"><span>ACTUAL RESULT<\/span><b>Volume, strength, wear and life<\/b><\/div><\/div>\n <div class=\"fpt-two-panel\"><div><span>PTFE COMPOUNDS<\/span><h3>Fillers change behavior<\/h3><ul><li>Wear resistance<\/li><li>Extrusion resistance<\/li><li>Strength<\/li><li>Thermal conductivity<\/li><\/ul><p>Some fillers can reduce compatibility with strong bases, hydrofluoric acid or other specific media.<\/p><\/div><div class=\"is-ffkm\"><span>FFKM COMPOUNDS<\/span><h3>Formulations differ<\/h3><ul><li>Acid resistance<\/li><li>Base and amine resistance<\/li><li>Steam resistance<\/li><li>Oxidizing chemistry<\/li><\/ul><p>Two FFKM grades can produce meaningfully different results in the same chemical.<\/p><\/div><\/div>\n <div class=\"fpt-data-strip\"><span>EXACT COMPOUND<\/span><span>CONCENTRATION<\/span><span>TEMPERATURE<\/span><span>DURATION<\/span><span>MIXTURES<\/span><span>PRESSURE<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-high-temp\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">05<\/span><div><p>HEAT WITH DIFFERENT LIMITS<\/p><h2>FFKM vs PTFE at High Temperature<\/h2><\/div><\/div>\n <p>Both materials perform at elevated temperature, but their advantages depend on the compound and sealing mechanism. Specialized FFKM grades can have published maximum temperatures above 300\u00b0C, while virgin PTFE is commonly used continuously around 260\u00b0C \/ 500\u00b0F.<\/p>\n <figure class=\"fpt-visual fpt-temperature-visual\"><div class=\"fpt-visual-head\"><span>GENERAL TEMPERATURE LANDSCAPE<\/span><strong>Published maxima are screening values\u2014not application guarantees<\/strong><\/div><div class=\"fpt-temperature-stage\"><div class=\"is-ptfe\"><span>VIRGIN PTFE<\/span><i><b>\u2248260\u00b0C<\/b><\/i><small>Typical continuous reference<\/small><\/div><div class=\"is-ffkm\"><span>SPECIALIZED FFKM<\/span><i><b>300\u00b0C+<\/b><\/i><small>Selected grades; service dependent<\/small><\/div><\/div><figcaption>Chemical media, pressure, motion, geometry, thermal cycling and required life can lower the practical limit.<\/figcaption><\/figure>\n <div class=\"fpt-warning\"><span>DO NOT SELECT BY MAXIMUM ALONE<\/span><p>A high-temperature FFKM may not have the right chemistry, while a PTFE design may be limited by fillers, creep, spring material or the mating hardware.<\/p><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-low-temp\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">06<\/span><div><p>THE CRYOGENIC DIVIDE<\/p><h2>FFKM vs PTFE at Low Temperature<\/h2><\/div><\/div>\n <p>PTFE can provide a major advantage in true cryogenic service. Engineered PTFE seal designs are used with liquid nitrogen, hydrogen, oxygen and helium at temperatures far below the practical low-temperature limits of typical FFKM compounds.<\/p>\n <div class=\"fpt-cryo-scale\"><div class=\"is-extreme\"><span>\u2248 \u2212260\u00b0C<\/span><b>Engineered PTFE designs<\/b><small>Application and design dependent<\/small><\/div><i><\/i><div class=\"is-special\"><span>\u2248 \u221240\u00b0C<\/span><b>Specialty low-temp FFKM<\/b><small>Compound dependent<\/small><\/div><i><\/i><div><span>\u221210 to \u221225\u00b0C<\/span><b>Typical FFKM ranges<\/b><small>Verify exact grade<\/small><\/div><em>WARMER \u2192<\/em><\/div>\n <div class=\"fpt-application-chips\"><span>LNG<\/span><span>Liquid nitrogen<\/span><span>Liquid oxygen<\/span><span>Hydrogen<\/span><span>Aerospace<\/span><span>Cryogenic valves<\/span><\/div>\n <blockquote><p>For true cryogenic sealing, an engineered PTFE seal is generally a more suitable starting point than an FFKM O-ring.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-friction\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">07<\/span><div><p>SLIDING RESISTANCE<\/p><h2>FFKM vs PTFE Friction<\/h2><\/div><\/div>\n <p>PTFE is the clear starting point when extremely low static and dynamic friction, reduced stick-slip or dry-running behavior is central to the application. FFKM behaves more like rubber and normally produces more friction.<\/p>\n <div class=\"fpt-friction-compare\"><div class=\"is-ffkm\"><span>FFKM<\/span><i><\/i><b>Moderate friction<\/b><small>Excellent for many static duties<\/small><\/div><em>SLIDING FORCE<\/em><div class=\"is-ptfe\"><span>PTFE<\/span><i><\/i><b>Extremely low friction<\/b><small>Self-lubricating dynamic behavior<\/small><\/div><\/div>\n <div class=\"fpt-application-grid\"><div><i>01<\/i><span>Reciprocating rods<\/span><\/div><div><i>02<\/i><span>Rotary shafts<\/span><\/div><div><i>03<\/i><span>Precision actuators<\/span><\/div><div><i>04<\/i><span>Analytical instruments<\/span><\/div><div><i>05<\/i><span>Semiconductor mechanisms<\/span><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-dynamic\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">08<\/span><div><p>MOTION CHANGES THE PRIORITY<\/p><h2>Dynamic Sealing: FFKM or PTFE?<\/h2><\/div><\/div>\n <div class=\"fpt-motion-map\"><div><span>STATIC<\/span><b>FFKM advantage<\/b><small>Recovery + simple O-ring gland<\/small><\/div><i>\u2192<\/i><div><span>SLOW MOVEMENT<\/span><b>Either may work<\/b><small>Chemistry and friction decide<\/small><\/div><i>\u2192<\/i><div><span>HIGH-CYCLE SLIDING<\/span><b>PTFE advantage<\/b><small>Friction + wear dominate<\/small><\/div><\/div>\n <div class=\"fpt-two-panel\"><div class=\"is-ffkm\"><span>FFKM DYNAMIC USE<\/span><h3>Useful when recovery matters<\/h3><ul><li>Critical chemical resistance<\/li><li>Relatively slow movement<\/li><li>Conventional O-ring geometry<\/li><li>Elastic conformity<\/li><\/ul><p>Watch friction, heat and wear as speed and cycling rise.<\/p><\/div><div><span>PTFE DYNAMIC USE<\/span><h3>Designed around sliding<\/h3><ul><li>Reciprocating motion<\/li><li>Rotary motion<\/li><li>Dry running<\/li><li>Precision movement<\/li><\/ul><p>Match filler, counterface hardness, surface finish, speed and lubrication.<\/p><\/div><\/div>\n <div class=\"fpt-source-note\"><b>Counterface note:<\/b> Some wear-resistant PTFE fillers can accelerate shaft wear when the mating surface is too soft. Treat the seal and counterface as one tribological system.<\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-spring\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">09<\/span><div><p>PTFE + CONTINUOUS FORCE<\/p><h2>Spring Energized PTFE vs FFKM O-Rings<\/h2><\/div><\/div>\n <p>A spring energized seal combines a PTFE or engineered polymer jacket with a metallic spring that continuously pushes the sealing lips against the hardware.<\/p>\n <figure class=\"fpt-visual fpt-spring-visual\"><div class=\"fpt-visual-head\"><span>SPRING-LOAD TRADE-OFF<\/span><strong>Contact force can be tuned for leakage, friction and wear<\/strong><\/div><div class=\"fpt-spring-stage\"><div><span>LIGHT SPRING<\/span><i class=\"is-light\"><\/i><b>Lower friction<\/b><small>Reduced wear and drive load<\/small><\/div><em>\u2194<\/em><div class=\"is-center\"><span>APPLICATION TARGET<\/span><i><\/i><b>Balanced contact<\/b><small>Leakage + friction + life<\/small><\/div><em>\u2194<\/em><div><span>HEAVY SPRING<\/span><i class=\"is-heavy\"><\/i><b>Higher sealing force<\/b><small>More friction and lip load<\/small><\/div><\/div><figcaption>Spring type, alloy and load are part of the seal specification\u2014not interchangeable details.<\/figcaption><\/figure>\n <div class=\"fpt-material-choice\"><div><span>CHOOSE AN FFKM O-RING WHEN<\/span><ul><li>Standard O-ring gland is preferred<\/li><li>Static sealing dominates<\/li><li>Elastic recovery is important<\/li><li>Very high temperature is required<\/li><li>Installation simplicity matters<\/li><\/ul><\/div><div class=\"is-ptfe\"><span>CHOOSE SPRING ENERGIZED PTFE WHEN<\/span><ul><li>Friction must be minimized<\/li><li>Dry running is required<\/li><li>Cryogenic or demanding vacuum duty exists<\/li><li>Dynamic movement is important<\/li><li>Elastomer compression set is problematic<\/li><\/ul><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-vacuum\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">10<\/span><div><p>LEAK RATE + MATERIAL BEHAVIOR<\/p><h2>FFKM vs PTFE for Vacuum Applications<\/h2><\/div><\/div>\n <p>Both materials are used in vacuum systems. The correct choice depends on whether elastic conformity, low friction, permeability, cryogenic capability or process purity limits performance.<\/p>\n <div class=\"fpt-vacuum-layout\"><div class=\"is-ffkm\"><span>FFKM ADVANTAGES<\/span><h3>Elastic static sealing<\/h3><ul><li>Continuous contact force<\/li><li>Good groove conformity<\/li><li>High-temperature capability<\/li><li>Conventional installation<\/li><li>Special low-outgassing grades<\/li><\/ul><\/div><div class=\"fpt-vacuum-core\"><span>VACUUM SYSTEM<\/span><i><\/i><b>Required leak rate<\/b><\/div><div class=\"is-ptfe\"><span>PTFE ADVANTAGES<\/span><h3>Engineered low-friction sealing<\/h3><ul><li>Low gas permeability<\/li><li>Low friction<\/li><li>Cryogenic capability<\/li><li>Broad chemical resistance<\/li><li>Spring energized options<\/li><\/ul><\/div><\/div>\n <div class=\"fpt-data-strip\"><span>OUTGASSING<\/span><span>PERMEATION<\/span><span>CROSS-SECTION<\/span><span>SURFACE FINISH<\/span><span>TEMPERATURE<\/span><span>LEAK RATE<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-pressure\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">11<\/span><div><p>GLAND DESIGN STILL RULES<\/p><h2>Pressure and Extrusion Resistance<\/h2><\/div><\/div>\n <p>Neither FFKM nor virgin PTFE should be specified for high pressure without reviewing clearance, temperature, compound deformation and backup support.<\/p>\n <div class=\"fpt-pressure-compare\"><div class=\"is-ffkm\"><span>FFKM RISK<\/span><h3>Extrusion through clearance<\/h3><p>Pressure, temperature, swelling, softness and a large gap can produce nibbled or torn edges.<\/p><b>HARDNESS \u00b7 GAP \u00b7 BACKUP RING<\/b><\/div><div class=\"is-ptfe\"><span>PTFE RISK<\/span><h3>Creep under sustained load<\/h3><p>Virgin PTFE can cold-flow; filled compounds improve compressive strength, wear and deformation resistance.<\/p><b>FILLER \u00b7 PROFILE \u00b7 SUPPORT MATERIAL<\/b><\/div><\/div>\n <figure class=\"fpt-visual fpt-gap-visual\"><div class=\"fpt-visual-head\"><span>HIGH-PRESSURE STACK<\/span><strong>Support can be as important as the primary seal material<\/strong><\/div><div class=\"fpt-gap-stage\"><div><span>PRESSURE<\/span><em>\u2192<\/em><i class=\"fpt-primary\"><\/i><i class=\"fpt-backup\"><\/i><i class=\"fpt-metal-top\"><\/i><i class=\"fpt-metal-bottom\"><\/i><b>CONTROLLED GAP<\/b><\/div><aside><span>OPTIONAL SUPPORT<\/span><p>Filled PTFE, PEEK or another high-strength material may be used as a backup element in severe duty.<\/p><\/aside><\/div><figcaption>Review peak pressure and cycling\u2014not only the normal gauge reading.<\/figcaption><\/figure>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-semiconductor\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">12<\/span><div><p>ONE TOOL, MULTIPLE MATERIALS<\/p><h2>FFKM vs PTFE for Semiconductor Equipment<\/h2><\/div><\/div>\n <p>Semiconductor systems frequently use both materials in different locations because static chamber sealing and precision chemical-delivery motion create different priorities.<\/p>\n <div class=\"fpt-semiconductor-map\"><div class=\"is-ffkm\"><span>FFKM ZONE<\/span><b>Chamber O-rings<\/b><b>Vacuum flanges<\/b><b>Process valves<\/b><b>Plasma chamber seals<\/b><small>Recovery \u00b7 purity \u00b7 heat \u00b7 plasma<\/small><\/div><i>+<\/i><div class=\"is-ptfe\"><span>PTFE ZONE<\/span><b>Chemical delivery<\/b><b>Dynamic valve seals<\/b><b>Spring energized seals<\/b><b>Precision motion<\/b><small>Friction \u00b7 dry running \u00b7 wet chemistry<\/small><\/div><\/div>\n <blockquote><p>The correct result may be a mixed-material sealing architecture rather than one universal material across the tool.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-pumps\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">13<\/span><div><p>LOCATION DETERMINES FUNCTION<\/p><h2>FFKM vs PTFE for Chemical Pumps and Valves<\/h2><\/div><\/div>\n <div class=\"fpt-equipment-map\"><div><span>STATIC BODY JOINT<\/span><b>FFKM O-ring<\/b><small>Pump casing \u00b7 valve body \u00b7 cartridge<\/small><\/div><i>\u2192<\/i><div><span>SLIDING INTERFACE<\/span><b>PTFE seal<\/b><small>Valve stem \u00b7 shaft \u00b7 dynamic seat<\/small><\/div><i>\u2192<\/i><div><span>DEMANDING DYNAMIC<\/span><b>Spring energized PTFE<\/b><small>Low friction \u00b7 vacuum \u00b7 long life<\/small><\/div><\/div>\n <div class=\"fpt-five-inputs\"><span>CHEMICAL MEDIA<\/span><span>PRESSURE<\/span><span>MOTION<\/span><span>TEMPERATURE<\/span><span>LEAKAGE REQUIREMENT<\/span><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-deformation\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">14<\/span><div><p>DIFFERENT LONG-TERM FAILURE MODES<\/p><h2>Compression Set vs Creep<\/h2><\/div><\/div>\n <div class=\"fpt-deformation-compare\"><div class=\"is-ffkm\"><span>FFKM \u00b7 COMPRESSION SET<\/span><i><\/i><h3>Elastic recovery is lost<\/h3><p>Heat, compression and chemicals can leave a permanent flat shape, reduce contact force and cause leakage.<\/p><\/div><div class=\"is-ptfe\"><span>PTFE \u00b7 CREEP \/ COLD FLOW<\/span><i><\/i><h3>Material deforms under load<\/h3><p>Time, pressure and temperature can change the profile; fillers, geometry and energization are used to control it.<\/p><\/div><\/div>\n <div class=\"fpt-equation\"><span>FFKM DESIGN<\/span><b>RECOVERY + COMPRESSION SET<\/b><i>vs<\/i><span>PTFE DESIGN<\/span><b>CREEP + ENERGIZATION<\/b><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-installation\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">15<\/span><div><p>ASSEMBLY FOLLOWS MATERIAL BEHAVIOR<\/p><h2>Installation Differences<\/h2><\/div><\/div>\n <div class=\"fpt-install-grid\"><div class=\"is-ffkm\"><span>FFKM O-RING<\/span><h3>Conventional gland installation<\/h3><ul><li>Avoid cuts and sharp edges<\/li><li>Prevent twisting<\/li><li>Use compatible lubrication<\/li><li>Control stretch<\/li><li>Confirm squeeze and fill<\/li><\/ul><\/div><div class=\"is-ptfe\"><span>PTFE SEAL<\/span><h3>Specialized tools may be required<\/h3><ul><li>Installation cones<\/li><li>Sizing tools<\/li><li>Split glands<\/li><li>Special assembly procedures<\/li><li>Correct pressure orientation<\/li><\/ul><\/div><\/div>\n <div class=\"fpt-orientation-card\"><span>SPRING ENERGIZED SEAL<\/span><div><b>PRESSURE SIDE<\/b><i>\u2192<\/i><em>OPEN JACKET \/ SPRING CAVITY<\/em><i>\u2192<\/i><b>SEALING LIPS<\/b><\/div><p>Installing a directional seal backward can prevent proper pressure energization.<\/p><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-cost\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">16<\/span><div><p>COMPARE THE COMPLETE SYSTEM<\/p><h2>Is FFKM or PTFE More Expensive?<\/h2><\/div><\/div>\n <p>There is no universal answer. FFKM molded parts have premium material cost, while a machined filled-PTFE profile, spring energized jacket and specialty alloy spring can also be expensive.<\/p>\n <div class=\"fpt-cost-equation\"><div><span>SEAL<\/span><b>Part price<\/b><\/div><i>+<\/i><div><span>HARDWARE<\/span><b>New gland or counterface<\/b><\/div><i>+<\/i><div><span>INSTALL<\/span><b>Tools and labor<\/b><\/div><i>+<\/i><div><span>RISK<\/span><b>Leakage + downtime<\/b><\/div><i>\u00d7<\/i><div><span>FREQUENCY<\/span><b>Replacement interval<\/b><\/div><em>= TOTAL SEALING COST<\/em><\/div>\n <div class=\"fpt-two-panel\"><div class=\"is-ffkm\"><span>FFKM EXAMPLE<\/span><h3>Higher material, familiar gland<\/h3><p>A premium O-ring may fit the existing groove and avoid hardware redesign.<\/p><\/div><div><span>PTFE CONVERSION EXAMPLE<\/span><h3>New geometry, longer dynamic life<\/h3><p>A spring energized conversion may require a new gland but reduce friction and replacement frequency.<\/p><\/div><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-choose-ffkm\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">17<\/span><div><p>ELASTIC EXTREME-SERVICE SEALING<\/p><h2>When Should You Choose FFKM?<\/h2><\/div><\/div>\n <div class=\"fpt-choice-card is-ffkm\"><div><span>FFKM IS USUALLY THE BETTER CANDIDATE WHEN<\/span><h3>Recovery and static sealing lead the specification.<\/h3><ul><li>You want a conventional elastomer O-ring<\/li><li>Static sealing dominates<\/li><li>Broad chemical resistance is required<\/li><li>Extreme high-temperature capability is needed<\/li><li>Elastic recovery is important<\/li><li>High-purity elastomer sealing is required<\/li><\/ul><\/div><aside><span>TYPICAL APPLICATIONS<\/span><b>Chemical reactors<\/b><b>Semiconductor chambers<\/b><b>Chemical pumps<\/b><b>Pharmaceutical valves<\/b><b>High-temperature systems<\/b><\/aside><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-choose-ptfe\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">18<\/span><div><p>LOW-FRICTION ENGINEERED SEALING<\/p><h2>When Should You Choose PTFE?<\/h2><\/div><\/div>\n <div class=\"fpt-choice-card is-ptfe\"><div><span>PTFE IS OFTEN THE BETTER CANDIDATE WHEN<\/span><h3>Motion, friction or extreme low temperature lead.<\/h3><ul><li>Friction must be very low<\/li><li>Dry running is required<\/li><li>Cryogenic temperatures are involved<\/li><li>Dynamic movement is significant<\/li><li>Chemical compatibility must be extremely broad<\/li><li>Elastomer swelling is unacceptable<\/li><\/ul><\/div><aside><span>TYPICAL APPLICATIONS<\/span><b>Rotary equipment<\/b><b>Reciprocating systems<\/b><b>Cryogenic valves<\/b><b>Chemical valves<\/b><b>HPLC equipment<\/b><b>Semiconductor mechanisms<\/b><\/aside><\/div>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-choose-spring\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">19<\/span><div><p>PTFE PROPERTIES + MECHANICAL FORCE<\/p><h2>When Should You Choose a Spring Energized PTFE Seal?<\/h2><\/div><\/div>\n <div class=\"fpt-spring-combination\"><div><span>AGGRESSIVE CHEMICAL<\/span><\/div><i>+<\/i><div><span>LOW PRESSURE \/ VACUUM<\/span><\/div><i>+<\/i><div><span>EXTREME TEMPERATURE<\/span><\/div><i>+<\/i><div><span>LOW FRICTION<\/span><\/div><i>+<\/i><div><span>DYNAMIC MOVEMENT<\/span><\/div><em>SPRING ENERGIZED PTFE<\/em><\/div>\n <blockquote><p>The spring provides continuous sealing force that PTFE cannot generate through natural elasticity alone.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-selection\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">20<\/span><div><p>INITIAL SCREENING MATRIX<\/p><h2>Practical FFKM vs PTFE Selection Table<\/h2><\/div><\/div>\n <div class=\"fpt-table-wrap\" role=\"region\" aria-label=\"Practical FFKM and PTFE selection table\" tabindex=\"0\"><table><thead><tr><th>Application requirement<\/th><th>Usually consider first<\/th><\/tr><\/thead><tbody>\n <tr><td>Standard extreme-chemical O-ring<\/td><td><b class=\"fpt-label is-ffkm\">FFKM<\/b><\/td><\/tr><tr><td>Static seal above 300\u00b0C<\/td><td><b class=\"fpt-label is-ffkm\">Suitable FFKM compound<\/b><\/td><\/tr><tr><td>Low-friction reciprocating seal<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Rotary shaft sealing<\/td><td><b class=\"fpt-label is-ptfe\">PTFE-based design<\/b><\/td><\/tr><tr><td>Cryogenic sealing<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Semiconductor chamber O-ring<\/td><td><b class=\"fpt-label is-ffkm\">Semiconductor-grade FFKM<\/b><\/td><\/tr><tr><td>Chemical valve seat<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Chemical pump secondary O-ring<\/td><td><b class=\"fpt-label is-ffkm\">FFKM<\/b><\/td><\/tr><tr><td>Dry-running seal<\/td><td><b class=\"fpt-label is-ptfe\">PTFE<\/b><\/td><\/tr><tr><td>Low-pressure dynamic seal<\/td><td><b class=\"fpt-label is-spring\">Spring energized PTFE<\/b><\/td><\/tr><tr><td>Conventional elastic O-ring gland<\/td><td><b class=\"fpt-label is-ffkm\">FFKM<\/b><\/td><\/tr><tr><td>Extreme chemical + precision motion<\/td><td><b class=\"fpt-label is-spring\">Spring energized PTFE<\/b><\/td><\/tr>\n <\/tbody><\/table><\/div>\n <p class=\"fpt-table-note\">This is a screening guide, not a final material approval. Verify the exact formulation, geometry and operating conditions.<\/p>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-information\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">21<\/span><div><p>INPUTS BEFORE MATERIAL SELECTION<\/p><h2>Information Needed Before Choosing<\/h2><\/div><\/div>\n <div class=\"fpt-input-grid\"><article><i>01<\/i><h3>Media<\/h3><p>Chemical names, concentrations, gases, cleaners and lubricants.<\/p><\/article><article><i>02<\/i><h3>Temperature<\/h3><p>Startup, normal, continuous maximum and peak.<\/p><\/article><article><i>03<\/i><h3>Pressure \/ vacuum<\/h3><p>Normal, maximum, vacuum level and pressure direction.<\/p><\/article><article class=\"is-motion\"><i>04<\/i><h3>Motion<\/h3><p>Static, reciprocating, rotary or oscillating; include speed, stroke and cycle frequency.<\/p><\/article><article><i>05<\/i><h3>Hardware<\/h3><p>Shaft or bore diameter, groove, clearance and surface finish.<\/p><\/article><article><i>06<\/i><h3>Current failure<\/h3><p>Leakage, swelling, set, friction, extrusion, wear and service life.<\/p><\/article><\/div>\n <a class=\"fpt-inline-cta\" href=\"#fpt-contact\"><span>READY FOR A MATERIAL REVIEW?<\/span><b>Send these six input groups<\/b><i>\u2192<\/i><\/a>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-mistakes\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">22<\/span><div><p>SEVEN AVOIDABLE ERRORS<\/p><h2>Common Selection Mistakes<\/h2><\/div><\/div>\n <div class=\"fpt-mistake-list\"><article><span>01<\/span><div><h3>Assuming PTFE behaves like a rubber O-ring<\/h3><p>Limited recovery often requires a different profile, gland or energizer.<\/p><\/div><\/article><article><span>02<\/span><div><h3>Assuming all FFKM compounds are identical<\/h3><p>Formulations vary substantially in chemical and temperature performance.<\/p><\/div><\/article><article><span>03<\/span><div><h3>Comparing only maximum temperature<\/h3><p>The highest rating may not suit the actual chemical, motion or service life.<\/p><\/div><\/article><article><span>04<\/span><div><h3>Ignoring PTFE fillers<\/h3><p>Fillers change wear, creep, pressure capability and chemical compatibility.<\/p><\/div><\/article><article><span>05<\/span><div><h3>Ignoring motion<\/h3><p>A strong static material choice may fail in high-speed dynamic service.<\/p><\/div><\/article><article><span>06<\/span><div><h3>Putting PTFE in the same FFKM groove<\/h3><p>The two materials generate and retain sealing force differently.<\/p><\/div><\/article><article><span>07<\/span><div><h3>Choosing by part price alone<\/h3><p>Hardware conversion, downtime, leakage risk and replacement frequency matter.<\/p><\/div><\/article><\/div>\n <\/section>\n\n <section class=\"fpt-section fpt-summary-section\" id=\"fpt-summary\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">23<\/span><div><p>MATERIAL NAME IS THE START<\/p><h2>Choose the Complete Sealing System<\/h2><\/div><\/div>\n <div class=\"fpt-summary-pair\"><div class=\"is-ffkm\"><span>FFKM IS AN ELASTOMER<\/span><b>Elastic recovery<\/b><b>Conventional O-ring sealing<\/b><b>Exceptional chemical resistance<\/b><b>Very high temperature capability<\/b><\/div><div class=\"is-ptfe\"><span>PTFE IS A FLUOROPOLYMER<\/span><b>Extremely low friction<\/b><b>Dry-running behavior<\/b><b>Exceptional cryogenic capability<\/b><b>Engineered dynamic sealing<\/b><\/div><\/div>\n <div class=\"fpt-summary-inputs\"><span>CHEMICAL<\/span><i>+<\/i><span>TEMPERATURE<\/span><i>+<\/i><span>PRESSURE<\/span><i>+<\/i><span>MOTION<\/span><i>+<\/i><span>GROOVE<\/span><i>+<\/i><span>SERVICE LIFE<\/span><b>= RIGHT SEAL<\/b><\/div>\n <blockquote><p>Neither FFKM nor PTFE should be selected by material name alone. Select the compound, profile, energizer, gland and counterface as one system.<\/p><\/blockquote>\n <\/section>\n\n <section class=\"fpt-section\" id=\"fpt-faq\">\n <div class=\"fpt-section-heading\"><span class=\"fpt-section-index\">24<\/span><div><p>QUICK ANSWERS<\/p><h2>Frequently Asked Questions<\/h2><\/div><\/div>\n <div class=\"fpt-faq-list\">\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Is FFKM the same as PTFE?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>No. FFKM is a perfluoroelastomer with rubber-like elasticity. PTFE is a fluoropolymer with very low friction and limited natural elastic recovery.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which has better chemical resistance?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Both provide exceptionally broad resistance. The exact FFKM formulation, PTFE compound, chemistry and operating conditions must be checked.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which has better high-temperature resistance?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Specialized FFKM grades can have published maxima above 300\u00b0C. Virgin PTFE is commonly used continuously around 260\u00b0C, although engineered compounds vary.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which is better at low temperatures?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>PTFE generally has a major advantage in extreme low-temperature and cryogenic applications.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which has lower friction?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>PTFE generally provides much lower friction than FFKM.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Can PTFE replace an FFKM O-ring?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Not as a direct substitution in many cases. PTFE has different recovery and creep behavior and may need a different groove or spring energizer.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Can FFKM replace PTFE?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Sometimes in static O-ring applications, but it may create more friction and have less low-temperature capability.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>What is a spring energized PTFE seal?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>It is a PTFE or engineered polymer jacket containing a metal spring that continuously pushes the sealing lips against the hardware.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which is better for vacuum?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Both can work. FFKM is convenient for elastic static sealing, while energized PTFE can offer advantages in demanding vacuum, low-friction and cryogenic duty.<\/p><\/div><\/div>\n <div class=\"fpt-faq-item\"><button type=\"button\" aria-expanded=\"false\"><span>Which is better for semiconductor equipment?<\/span><i><\/i><\/button><div class=\"fpt-faq-answer\"><p>Both are used in different locations: FFKM commonly serves chambers and static seals, while PTFE-based seals often serve dynamic mechanisms and chemical delivery.<\/p><\/div><\/div>\n <\/div>\n <\/section>\n\n <section class=\"fpt-contact\" id=\"fpt-contact\"><div class=\"fpt-contact-grid\"><div><span class=\"fpt-eyebrow\">CUSTOM FFKM & PTFE SEALING<\/span><h2>Need Help Choosing Between FFKM and PTFE?<\/h2><p>Walle Seals manufactures custom FFKM O-rings, gaskets, molded components, filled PTFE profiles and spring energized sealing solutions.<\/p><a href=\"\/contact-us\/\" class=\"fpt-button is-light\">Discuss your application <i>\u2192<\/i><\/a><\/div><div class=\"fpt-contact-spec\"><span>SEND US<\/span><ul><li>Chemicals and concentrations<\/li><li>Temperature range<\/li><li>Pressure or vacuum level<\/li><li>Static, reciprocating or rotary motion<\/li><li>Seal and groove dimensions<\/li><li>Surface finish and hardware material<\/li><li>Failure symptoms and required life<\/li><\/ul><\/div><\/div><\/section>\n <\/article>\n <\/main>\n <\/div>\n <button class=\"fpt-back-top\" type=\"button\" data-fpt-back-top aria-label=\"Back to top\"><span>\u2191<\/span><\/button>\n<\/div>\n <script>\n\/* WordPress JavaScript \u6a21\u5757\uff1a\u590d\u5236\u672c\u6587\u4ef6\u5168\u90e8\u5185\u5bb9\uff0c\u4e0d\u8981\u6dfb\u52a0 script \u6807\u7b7e\uff1b\u65e0\u9700 jQuery\u3002 *\/\n(function () {\n \"use strict\";\n\n function init(root) {\n if (!root) return;\n if (root.dataset.fptReady === \"true\") return;\n root.dataset.fptReady = \"true\";\n\n var article = root.querySelector(\"[data-fpt-article]\");\n var progress = root.querySelector(\"[data-fpt-progress]\");\n var backTop = root.querySelector(\"[data-fpt-back-top]\");\n var toc = root.querySelector(\"[data-fpt-toc]\");\n var toggle = root.querySelector(\"[data-fpt-toc-toggle]\");\n var shell = root.querySelector(\"[data-fpt-shell]\");\n var sidebar = root.querySelector(\"[data-fpt-sidebar]\");\n var card = root.querySelector(\"[data-fpt-sidebar-card]\");\n var links = toc ? 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Seals: Which Material Is Right for Your Application? Compare how elasticity, creep, friction, temperature, pressure, vacuum and motion change the correct choice between an FFKM O-ring and an engineered PTFE seal. Compare the materials \u2193 Open the […]<\/p>\n","protected":false},"author":1,"featured_media":7030,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_themeisle_gutenberg_block_has_review":false,"footnotes":""},"categories":[85,106],"tags":[],"class_list":["post-6827","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-materials-compatibility"],"_links":{"self":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts\/6827","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/comments?post=6827"}],"version-history":[{"count":1,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts\/6827\/revisions"}],"predecessor-version":[{"id":6828,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/posts\/6827\/revisions\/6828"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/media\/7030"}],"wp:attachment":[{"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/media?parent=6827"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/categories?post=6827"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/walleglobal.com\/fr\/wp-json\/wp\/v2\/tags?post=6827"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}