The main points of the seal are as follows

(1) Choose appropriate seal material and hydraulic oil, as well as adaptability to working temperature and compatibility to oil.

(2) The geometric position accuracy (concentricity) of the sliding parts relative to the seal is high and the material is good (such as hard chrome plating) and the surface roughness is finer to extend the service life.

For oil seals used in hydraulic pumps and motor journals, not only the roughness of the sliding surface is required to be within 0.25m, but also hard chrome plating is required on the surface. In specific use, the radial direction of the oil seal lip needs to be adjusted appropriately according to the specific conditions. The spring force makes it tight enough, and an installation sleeve or thin washer should be used to protect the sealing ring during installation to prevent the lip from turning and twisting, causing the spring to slip out.

The commonly used rolling processing method for the inner surface of the hydraulic cylinder not only improves the surface roughness, but also makes the surface hardened by cold work, which is beneficial to prolong the service life of the seal ring. In addition, the pressure used, the length and type of the sliding surface also have a great influence on the service life. Therefore, the "scheduled inspection" time should be determined based on these conditions.

The lubrication of the sealing surface is required to be in good condition to prevent dirt from invading people. The use of oil up to the required cleanliness level and the correct installation method are also necessary conditions.