Oil seals are sealing components used to seal the rotating shafts in mechanical equipment, and the cavity is basically stationary, so oil seals are also called rotating shaft lip seals. The friction part of the machine has oil entering it when the machine is running, so oil seals are used to prevent the oil from leaking from the gaps in the machine. In addition to oil, it is also necessary to prevent the leakage of water and chemical liquids, as well as dust and sand from the outside. At this time, oil seals are also needed.