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(208) 413-6377 8am-3pm Pacific Mon-Friday |Cage Code: 72PR0

Back-Up Rings

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. 


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The O-ring Store offers great deals on a large selection of AS568 Buna-N O-rings (Nitrile), Metric Buna-N O-rings (Nitrile), Standard O-rings, Metric O-rings, Viton O-rings, Viton Extreme O-rings, in many compounds and colors. We are the best source for common and not so common o-rings. Buy o-rings online, fax 208-413-3719 or call 208-413-6377. The O-ring Store can save you hundreds of dollars and deliver quicker than most o-ring suppliers world wide! Plus convenient, flat fee shipping from FedEx and the US Postal Service.


Welcome to The O-ring Store, were you can find a huge selection of o-rings, hydraulic seals, o-ring kits and accessories. We have factory and custom made repair kits to provide you with o-rings and seals to fix everything from paintball guns, pools, sprayers, air tools to large hydraulic cylinders. In addition to our inventory we use many factories, suppliers, and even competitors to get what you need, when you need it, were you need it, at an agreed upon price with no surprises. We are continuing to expanding our selection of Hydraulic Seals, Oil Seals, O-ring Kits, rebuild kits and O-rings. We make getting O-rings easy!

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