How To Avoid Seal Failure?
Nov 22, 2022
1. Improper installation
In order to prevent the seal from being installed in the wrong direction or being damaged during installation, it is important to use the correct installation tools.
If it is difficult to install the seal in the cylinder, a special installation tool with a leading chamfer shall be used. At the same time, ensure that there is no squeal in the seal groove that damages the seal.
Another common cause of seal failure is that the seal is installed in the wrong direction. Installation training can avoid such problems. If this is not enough, the seal manufacturer should consider changing the design to avoid installing crops or using products that can only be installed in one direction.
2. Wear
As the service time increases, the seal will wear, but there are many ways to extend its service life. For example, contaminants are a common cause of excessive wear. Contaminants may come from gears or pumps rotating outside or inside the system. Although the filtering device helps prevent pollutants from affecting the seal, many devices cannot fully filter, and particles small enough to penetrate the filtering device can enter the oil cylinder and accelerate the wear of the seal.
The hydraulic oil can better isolate pollutants outside the sealing area, because if the seal fails faster than expected, the hydraulic oil can be replaced.
3. Extrusion
This type of seal failure is more familiar to designers, where overloaded pressure levels can cause seals to break and squeeze into hardware gaps. This problem can be avoided by using retaining rings or by changing the seal material from elastomer to thermoplastic. At the same time, the design can be changed to reduce the clearance of moving parts and minimize the space that can be extruded by the seals.
4. Compression permanent deformation
Low pressure leakage is a sign of reduced elasticity of seals, which is usually called compression permanent deformation. This is more likely with rubber polymer seals. The sealing element is very dependent on its elasticity under low pressure, which is why low pressure leakage is a common phenomenon of this kind of problem. The solutions include replacing seals, increasing preventive maintenance of seals, and replacing them with materials that are not easily affected by compression deformation.
