Back-Up Ring Kits

Extrusion failure is one of the most common types of O-ring failure. When the pressure becomes too great, the O-ring will actually extrude into the clearance gap. This will quickly nibble the O-ring away causing a loss of material, and once sufficient material is lost, seal failure will quickly follow. 

There are three options to prevent this, the first of which is to reduce the clearances to lower the extrusion gap. This is obviously an expensive option, so a cheaper solution is to raise the durometer of the O-ring. Although, a higher durometer O-ring offers superior extrusion resistance, the fact that harder durometer materials have limited low pressure sealability and is often difficult to source due to material availability. The last and best option is the addition of a backup ring. A backup ring is a ring of hard, extrusion resistant material such as high durometer nitrile, nylon, Hytrel, or PTFE. A back-up ring is designed to fit between the O-ring and the extrusion gap and prevent the extrusion of the O-ring. 

Product Image Model Product Name Qty. Price Quantity Discounts
(image for) OSK™ Back-up Rings Nitrile Duro 90 Kit 36-Sizes 293-Pieces K293X36B
OSK™ Back-up Rings Nitrile Duro 90 Kit 36-Sizes 293-Pieces
Contoured Back-up Ring Kit Contoured back-up rings are anti-extrusion devices, generally recommended when systemic pressure exceeds 1500 psi. The...
In Stock: 5
Quantity Discounts
Copyright © 2024 The O-Ring Store, LLC
1847 Wilma Dr, Clarkston WA 99403
Phone 208-413-6377 - Fax 208-413-6719