This guide provides general sourcing information. Final sealing decisions should be validated against the actual application and applicable standards.
Start with the operating conditions
The correct material depends on the fluid or gas, working temperature, pressure, motion, and expected service life. Share these conditions before comparing prices because two visually identical O-rings can perform very differently.
Common material choices
NBR is widely used with oils and general industrial fluids. FKM is selected for higher temperature and chemical resistance. EPDM is often suited to water, steam, and outdoor environments but is generally not used with petroleum oils. Silicone performs across a broad temperature range and is often selected where flexibility is important.
Confirm before mass production
Ask your supplier to confirm material, hardness, dimensions, tolerances, and test requirements in writing. For a new application, samples and application testing reduce purchasing risk before a production order.