O-Rings - ECO, 70 Shore A
O-rings are circular sealing rings with a round cross-section. When an O-ring is fitted into a groove and compressed between two surfaces, it forms a seal that prevents the escape of liquids or gases. O-rings are suitable for both static and dynamic applications.
These O-rings are made from ECO (epichlorohydrin rubber), a copolymer of epichlorohydrin and ethylene oxide. ECO has excellent resistance to hydrocarbon oils and fuels, very low gas permeability, and excellent resistance to ozone and weathering. Compared with standard nitrile, it offers better heat and ozone resistance, and it remains flexible at low temperatures. At 70 Shore A, the material offers a good balance of flexibility and durability, making it the standard choice for general-purpose sealing.
Chemical Compatibility
ECO is recommended for use with hydrocarbon oils, petrol, diesel and other hydrocarbon fuels.
Limitations
ECO is not recommended for use with ketones, esters, aldehydes, chlorinated hydrocarbons, nitro hydrocarbons or brake fluids. Its compression set resistance is limited at elevated temperatures.
Applications
These O-rings are suitable for automotive fuel systems, air-conditioning systems, petroleum industry equipment, pumps and valves.
Installation Guidance
Make sure that the groove and mating surfaces are clean and free from burrs. The 70 Shore A compound is flexible enough to fit easily and to seal well against a range of surface finishes. For high-pressure applications or larger clearance gaps, a harder grade or back-up rings may be required to prevent extrusion. Apply a thin film of compatible lubricant before fitting, and do not stretch or roll the O-ring over sharp edges or threads.
All dimensions are nominal. The information provided by AH Design Components Ltd is for reference only and is not a manufacturing specification. Please confirm that the product is suitable for your application before use.