Hydraulic Cylinder Reciprocating Combination Seals

Hydraulic cylinder reciprocating combination seals

The combination seals is the most commonly used seals in hydraulic cylinders, it is a typical lip seal consisting of a star seal that combines two or more sealing elements. DSH Seals gives you a general knowledge of the combination seals. Whether the combination seal is used for pistons or rod, the u-rings can only be sealed with a lip. The deformation of the surplus produces a seal. Due to the small contact area, the frictional force is relatively low. As the pressure increases, the elastic deformation of the lip increases, the tensile, compressive and bending stresses increase, and the radial pressing force of the u-ring automatically increases. The length in contact with the sealing surface is increased until the entire axial length of the u-ring is in contact with the sealing surface, thereby ensuring good sealing under high pressure.

combination seals ( DSH Seals product code: DAQ)

Sealing performance analysis of combination seals:

The combination seals is a self-tightening double-acting sealing element. It adopts a four-lip seal and is similar in shape to “X”. It is an improvement of the performance double on the basis of the O-rings. As with O-rings, O-rings can be replaced in most cases. The difference is that the structure of the star combination seal makes it more suitable for dynamic sealing.

Mainly because of its special star-shaped cross-section, it does not roll and twist in the groove during reciprocation. It requires a relatively small radial compression compared to the O-ring, resulting in less friction the wear amount is also small. Compared with the O-ring, its flash position is in the recess of the section, and the cross section has a good pressure distribution, which can obtain a good sealing effect. The star combination seal lip a lubricating cavity is formed between them, which has a small frictional resistance, improves the start-up, and is more suitable for transporting the seal.