The function of the seal is to close the gap where the oil in the tank chamber overflows, and to prevent dust, sand and other dirt from invading the inside of the tank chamber. However, if it is improperly installed or used, it will easily cause oil leakage and affect the normal operation of the machine. 75-A Cause burnt bearings, broken gears, twisted drive shafts or other serious failures.

      Seals can be roughly divided into rotary shaft oil seals, water seals, dust seals, piston and piston rod seals, etc. Many of them are used for dustproof, waterproof and sound insulation in daily life, and many of them are used for sealing oil in industrial machinery and equipment. , waterproof and dustproof and the like.