4 reasons why seals are damaged in application
Nov 14, 2021
The seal is used to prevent leakage, but the cause of leakage is not always the seal. Correct application is also very important.
Design
1) The selected seal does not match the hydraulic oil, working temperature, and working pressure, resulting in damage to the seal.
2) The size of the sealing groove is incorrect, causing the sealing ring to be squeezed into the sealing gap and damaged.
3) Corresponding parts, including the bottom of the seal groove, have not reached the surface roughness, dimensional tolerance, shape and position deviation required by the supplier of the seal ring.
4) Omission of the pre-compression guide of the seals, resulting in part of the seals being cut off during installation.
5) Many seals are used to withstand positive pressure. If there is negative pressure, flow in the reverse direction. It will pull the seal ring. Therefore, it is necessary to consider various load force conditions that may be encountered in the design to avoid negative pressure.
Processing
If the bottom of the seal groove is not concentric with the outer circle, the installation space on both sides will be improperly distributed, and the compressed condition will be different after installation, and the sealing effect will also be damaged.
Installation tool
The sealing lip is the most critical part to ensure the sealing function, but it is often very delicate and delicate. If the tools used during installation are not appropriate or are too rough, they are easily damaged.
Run
1) If the metal surface of the relative movement is damaged, it is easy to damage the seal. This is particularly likely to occur at the seal of the piston rod, which is damaged by foreign objects when exposed to the outside.
2) The pollution particles in the hydraulic oil, especially the hard metal particles, are also easy to damage the sealing ring. The sealing ring has a strong adaptability to the roundness of the shaft or hole, but the sealing ability to the axial fine lines is much worse.
3) The temperature of the oil in the hydraulic cylinder is often higher than the oil tank. Therefore, pay attention to limiting the temperature in the hydraulic cylinder and not exceed the allowable temperature of the seal.
