What is the range of the interference of the sealing ring is generally appropriate?

2022 06/28

The standard dynamic seal is generally 10~15% of the cut diameter, and the static seal is 15~20%. The interference of the O-ring is generally about 15%-30% in the static seal. In the dynamic seal, it is about 9%-25%, and the gas seal is halved.

Other factors that affect the sealing performance of the sealing ring
1. The hardness of the O-ring

O-ring material hardness is an important indicator for evaluating sealing performance. The hardness determines the amount of compression of the O-ring and the allowable extrusion gap of the groove. Since the nitrile seal of Shore A70 can meet most of the conditions of use, there is no special description for the sealing material, and the nitrile rubber of Shore A70 is generally provided.

2. Extrusion gap: The allowable extrusion gap gmax is related to the system pressure, the diameter of the O-ring section and the hardness of the material. Generally, the higher the working pressure, the smaller the allowable extrusion gap gmax. If the gap g exceeds the allowable range, the O-ring will be squeezed out and damaged.

3. When the pressure exceeds 5MPa, it is recommended to use a retaining ring;

4. For static sealing applications, the recommended combination is H7/g6.

Pre-compression: The O-ring is installed in the groove. To ensure its sealing performance, an initial compression should be reserved. For different applications, the amount of pre-compression relative to the section diameter W is also different. Usually about 15% to 30% in static seals, and about 9% to 25% in dynamic seals.