Frequently Asked Questions — EPDM O-Rings
What is EPDM rubber?
EPDM (Ethylene Propylene Diene Monomer) is a synthetic rubber with a fully saturated polymer backbone, giving it excellent resistance to heat, ozone, UV, and weathering. It is the preferred sealing material for water, steam, and outdoor applications where NBR or FKM would degrade quickly. EPDM is also compliant with many drinking water and food contact standards.
What temperature range can EPDM o-rings handle?
EPDM o-rings operate from −55 °C to +150 °C in continuous service. Some high-temperature EPDM grades are rated to +175 °C in hot water or low-pressure steam. The low-temperature limit is one of the best among standard elastomers, making EPDM suitable for outdoor winter sealing.
What chemicals is EPDM resistant to?
EPDM has excellent resistance to water, steam and hot water (up to 150 °C), DOT 3 and DOT 4 brake fluids, dilute acids and alkalis, ketones, ozone, and UV radiation. It is entirely incompatible with petroleum-based oils, fuels, aromatic solvents, and mineral hydraulic fluids — these cause rapid swelling and failure.
What are typical applications for EPDM o-rings?
EPDM o-rings are used in hot water and steam heating systems, automotive cooling circuits (water/glycol), HVAC equipment, outdoor weatherseals and window gaskets, brake hydraulics, pharmaceutical and food processing equipment, and drinking water installations where regulatory compliance (WRAS, KTW, NSF) is required.