The P03 type seal is a high-performance asymmetric U-shaped piston seal composed of polyurethane (PU) and polyoxymethylene (POM) integrated retaining ring. Adopting an asymmetric U-shaped cross-section structure, the seal is equipped with a pressure relief safety groove and an integral anti-extrusion ring. The outer sealing lip is designed with a retracted structure, and the inner diameter forms an interference fit with the groove bottom diameter. Compliant with ISO 5597 standard cavity dimensions, it is a professional one-way piston seal optimized for heavy-duty hydraulic working conditions, supporting back-to-back installation for dual-sided pressure scenarios.

• Polyurethane (PU): The main sealing body adopts high-performance polyurethane material, featuring excellent elasticity, compression resilience, wear resistance and superior static and dynamic sealing performance. It adapts to long-term frequent reciprocating motion of heavy-load hydraulic cylinders with stable sealing effect and strong fatigue resistance.
• Polyoxymethylene (POM): The integral POM retaining ring provides high rigidity and outstanding anti-extrusion capacity. It effectively supports the sealing body under high pressure, prevents seal deformation and extrusion damage, and greatly improves the overall structural stability and pressure resistance of the product.

• Standard ISO 5597 Cavity: Designed in strict accordance with ISO 5597 international standard groove specifications, it has strong versatility and interchangeability, convenient for standardized installation and replacement of equipment.
• Asymmetric U-shaped Cross-section & Retracted Outer Lip: The optimized asymmetric U-shaped structure and retracted outer sealing lip reduce running friction, optimize stress distribution, and improve the stability of dynamic reciprocating sealing.
• Interference Fit Design: The inner diameter is in interference fit with the groove bottom diameter, providing continuous and stable preload force to ensure tight fitting and zero-gap sealing.
• Excellent Static & Dynamic Sealing Performance: It maintains reliable pressure holding performance in static state and stable leakage-free sealing effect during high-frequency dynamic operation, adapting to long-term continuous heavy-duty work.
• High Anti-extrusion Performance: Equipped with an integral POM retaining ring, the product features ultra-high anti-extrusion ability, effectively resisting high-pressure extrusion and avoiding seal failure under large gap and high-pressure working conditions.
• Back-to-back Installation for Dual-sided Pressure: When the piston bears pressure on both sides, multiple P03 seals can be arranged back-to-back to realize stable two-way sealing, with strong adaptability to complex pressure alternating working conditions.
• Pressure Relief Safety Groove Design: The unique pressure relief safety groove effectively eliminates dynamic hysteresis stress and stick-slip problems during operation, ensuring smooth and stable movement of the cylinder.
• High Operational Reliability: The composite structure of PU main body and POM integral retaining ring, combined with optimized groove design, effectively reduces failure rate and ensures long-term stable operation of heavy-duty equipment.

Widely used in heavy-duty construction machinery, scrap steel shearing machinery and other heavy-load hydraulic equipment. It is suitable for high-pressure and heavy-duty piston sealing scenarios with bidirectional pressure alternating working conditions.