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Back-up Rings
Double E

Back-up Rings

Parco is a leading supplier of contoured, rubber back-up rings for use with O-rings in high-pressure applications. Pressure applied evenly to both sides of a seal normally has no effect on sealing performance. When a pressure difference is anticipated, elastomer selection must also consider differential pressure resistance. High differential pressures will cause improperly specified O-rings to extrude, resulting in seal damage and eventually failure. The use of back-up rings allows for substantial improvement in extrusion resistance. Parco’s 90-durometer back-up rings offer the protection you need for high-pressure applications.

View Back-up Ring Size Chart

Below is a list of our popular compounds for back-up rings.

Elastomer Compound Durometer
(Shore A)
Color Key Properties
Nitrile 2067-90 90 Black Extrusion and abrasion resistant; high pressure resistant
Nitrile 4900-90 90 Black Low cost; general purpose
Fluorocarbon 9009-90 90 Black High-temperature resistant; AMS 7259 and AMS R 83248 and MIL R 83248 compliant; QPL-listed

Learn more about O-ring Extrusion.

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