Sealing parts are materials or components that prevent the leakage of fluids or solid particles from adjacent joint surfaces, as well as the intrusion of external impurities such as dust and moisture into machinery and equipment.
Select appropriate sealing material, hydraulic oil, and ensure compatibility with operating temperature and oil.
High geometric position accuracy (concentricity), good material quality (such as hard chromium plating), and fine surface roughness of the parts sliding relative to the sealing elements can extend service life.
① For oil seals used on the journal of hydraulic pumps and motors, the surface roughness of the sliding surface is required to be within Ra 0.25μm, and hard chromium plating is required on the surface. During specific use, the radial spring force of the oil seal lip should be appropriately adjusted according to specific conditions to make it moderately tight. During installation, an installation sleeve or thin gasket should be used to protect the sealing ring to prevent the lip from curling or twisting, causing the spring to slip out.
② The inner surface of the hydraulic cylinder barrel is commonly processed by rolling, which not only improves the surface roughness but also performs cold work hardening treatment on the surface, which is beneficial to prolong the service life of the sealing ring. In addition, the applied pressure, the length of the sliding surface, and its type also have a significant impact on the service life. Therefore, the "regular inspection" interval should be determined based on these conditions.
③ It is required to maintain a good lubrication state on the sealing surface and prevent the intrusion of dirt. Using oil that meets the specified cleanliness level and correct installation methods are also key conditions.
