Backup rings are a perfect complement in use with O-rings, they serve as a protection of O-rings for a longer life. They also ensure that the O-rings retain their round shape even at high pressures and thus withstand even high pressure loads without damage. This is done by mounting the ring behind the O-ring on the low pressure side under a one-sided pressure load. In situations with changing pressure directions, we recommend the use of two backup rings, used on both sides of the O-ring.
Backup rings themselves have no sealing function, but are used in conjunction with O-rings to protect them from damage. They provide a high level of protection against damage to O-rings. For example, they serve as a supporting element to prevent gaps between radical seals and O-rings. Back Rings are widely used in hydraulics, for example in hydraulic valves and hydraulic pumps. They also provide exceptionally reliable sealing of ball valves or cylinder bottoms and heads as required in general industrial applications.
Most backup rings are made of PTFE and can therefore easily withstand extreme temperatures from -200 °C to 260 °C. In addition, there are elastomer Back Rings that can be stretched and thus easily mounted in installation grooves. Freudenberg guarantees the highest quality, durability and the best materials.
The complete range including product and material information sheets, ordering options, prices and availability can be found on our website.
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