Which material is better for high pressure resistant O-rings?
fluororubber
When choosing a material for high-pressure O-rings, fluoroelastomer (FKM) is usually considered a better choice. Fluorine rubber is famous for its excellent chemical resistance, heat resistance and oil resistance, and is suitable for sealing requirements in harsh environments such as high temperature, high pressure and high speed. It has good mechanical properties and resistance to ozone, aging and weathering, making it very suitable for high-pressure applications.
Although other materials such as nitrile rubber (NBR) also have good oil resistance, they may harden or age in high temperature and high pressure environments. Although hydrogenated nitrile rubber (H-NBR) has improved resistance to heat and resistance to ozone, aging and weathering, it is still not as resistant to high temperatures and pressures as fluororubber. Although ethylene propylene diene rubber (EPDM) has excellent ozone and hot water resistance, its applicable temperature range and oil resistance are not as good as fluororubber. Although silicone rubber (SI/VMQ) has excellent hygiene and resistance to bacterial growth, it is not as heat- and oil-resistant as fluororubber.
Therefore, taking into account high pressure resistance, chemical corrosion resistance and heat resistance, fluorine rubber (FKM) is a better choice.