27 6 月
How to Select X-Rings | Professional X-Ring Sizing Guide
Choosing the proper X-Ring (star-shaped quad ring) for your sealing application follows these professional selection criteria:
1. Static Seals & Reciprocating Linear Motion
Bore-mounted (housing) seals
The inner diameter of the X-Ring should match the groove dimension, or be roughly 2% smaller than the outer diameter of the groove. The pre-compression creates stable pre-tension and effectively prevents X-Ring twisting during operation.
Shaft-mounted seals
The X-Ring inner diameter needs to equal or slightly exceed the shaft outer diameter by 0.2–0.3 mm, or 1% larger than the shaft OD. This design simplifies installation and extends the service life of the quad ring.
2. Rotary Shaft Sealing
For rotary applications, select an X-Ring whose inner diameter is 2%–5% larger than the shaft diameter.
Rubber X-Rings generate friction heat while rotating, which causes elastomer shrinkage. The enlarged inner diameter maintains proper lubrication and ensures reliable long-term sealing performance.
3. X-Ring Material & Standard Specifications
The most common material is NBR 70 Shore A (N70 nitrile rubber). You can also adopt other elastomer grades that match standard O-Ring material options.
X-Ring dimensions fully conform to universal O-Ring size standards.