Seals are materials or components that prevent fluid or solid particles from leaking between adjacent bonding surfaces and prevent external impurities such as dust and moisture from entering the interior of machinery and equipment.

 

So, do you know what forms of damage seals can have?

1) Wear and tear

The sliding between the seal and the metal surface generates friction, leading to wear of the seal. The presence of pollutants in the oil (especially metal particles) and the high roughness of the metal surface, as well as factors such as being installed too tightly, accelerate this wear.

2) Gap squeezing deformation

The sealing element liquefies under high pressure and enters the gap of the sealing surface. The relative motion between the sealing element and the sealing groove promotes this process. The squeezing of the gap can cause complete damage to the sealing element, surface tearing or breakage, and may also result in plastic deformation. Adding a sealing ring can prevent extrusion.

3) Flip over

This type of malfunction is characterized by the partial extrusion of the seal from the groove when using lip seals (such as seals in hydraulic cylinders). When hydraulic equipment is running, the pressure in the sealing groove is very high. This pressure acts on the root of the seal, and the root is worn off. Then, under the action of friction, the seal is flipped over and pulled out of the sealing groove, and the sealing lip is cut open or crushed, completely damaging the seal.

4) Valley cracking

The valley of the lip seal is a stress concentration point, which is prone to cracking when subjected to pressure impact.

5) Twist. When lip seals generate significant friction during movement, they may experience complete or partial twisting.

6) Eccentric wear

This is one of the main reasons for seal damage. The seal itself is eccentric, the sealing support surface is eccentric, and there is some roughness on the mating surface between the reciprocating parts and the seal, which is subjected to radial loads, all of which cause eccentric wear.

7) Material aging

Seals become hard, brittle, and lose their elasticity due to prolonged use, storage, or other oxidation reasons, rendering them ineffective in sealing.