Back-Up Rings

Hard rubber molded contoured Back-Ups are routinely produced in a 90 durometer Nitrile and Viton. This provides sufficient elasticity to permit stretching over the major diameter of a piston and then snapping back into the gland groove cut into the piston.  90 durometer has sufficient hardness to resist extrusion of the softer elastomeric O-Ring performing the actual sealing function against the high pressure liquid or gas.

Back to the O-Ring Page