The service life and sealing performance of a seal ring in various applications depend on precise selection, which requires considering four core factors:
Media Compatibility: Ensure the rubber material is not corroded by the sealed medium (e.g., choose oil-resistant NBR for fuel applications or corrosion-resistant FKM for strong acids); otherwise, material swelling, hardening, or cracking may occur, leading to seal failure.
Temperature Range: Match the material to the operating temperature (e.g., choose VMQ for low temperatures around -40°C and FKM for high temperatures around 200°C); exceeding the material's temperature limits causes the rubber to lose elasticity and fail to seal effectively.
Pressure Rating: Select based on the pressure at the sealing interface (e.g., choose a seal ring with a thicker cross-section or a reinforced structure for high-pressure hydraulic systems, and a standard cross-section ring for low-pressure water pipes); excessive pressure can cause the seal ring to be "extruded" out of the sealing gap.
Motion State: Standard designs are suitable for static seals (e.g., flanges), whereas dynamic seals (e.g., pistons) require wear-resistant materials (such as NBR with a PTFE coating) to prevent premature wear caused by frequent friction.