Knowledge of skeleton oil seals (2) --- Function

Knowledge of skeleton oil seals (2) --- Function

The function of the skeleton oil seal is generally to isolate the parts that need lubrication in the transmission parts from the output parts, so as not to let the lubricating oil leak, usually used in the rotating shaft, is a rotating shaft lip seal. The skeleton acts like the steel bars inside the concrete component, which strengthens and allows the oil seal to maintain its shape and tension. According to the skeleton type, it can be divided into inner skeleton oil seal, outer skeleton oil seal, inner and outer exposed skeleton oil seal. Skeleton oil seal is made of high-quality nitrile rubber and steel plate, with stable quality and long service life. Widely used in automobiles, motorcycle crankshafts, camshafts, differentials, shock absorbers, engines, axles, front and rear wheels and other parts.

1. Prevent sediment, dust, water vapor, etc. from invading the bearing from the outside;

2. Limit the leakage of lubricating oil in the bearing. The requirements for oil seals are that the size (inner diameter, outer diameter and thickness) should comply with the regulations; It is required to have appropriate elasticity, which can properly jam the shaft and play a sealing role; To be heat-resistant, wear-resistant, strong, resistant to media (oil or water, etc.), long service life.

To use oil seals reasonably, the following points should be noted:
(1) The speed of the shaft Due to the design and structural reasons, the shaft with high speed should use high-speed oil seals, and the shaft with low speed should use low-speed oil seals, and the low-speed oil seal cannot be used on high-speed shafts, and vice versa.

(2) In the case of high ambient temperature, polypropylene ester or silicone, fluorine, silicone fluororubber should be selected. And try to reduce the oil temperature in the tank. In the case of too low a temperature, cold-resistant rubber should be selected.

(3) The oil seal with general pressure has poor pressure bearing capacity, and the oil seal will be deformed when the pressure is too large. Under the condition of excessive pressure, a pressure-resistant bearing ring or a reinforced pressure-resistant oil seal should be used.

(4) The eccentricity of the installation oil seal and the shaft are too large when the eccentricity is too large, and its tightness will become worse, especially when the shaft speed is high. If the eccentricity is too large, an oil seal with a "W" section can be used.

(5) The surface finish of the shaft directly affects the service life of the oil seal, that is, the high finish of the shaft, the service life of the oil seal will be long.

(6) Pay attention to the lip of the oil seal should have a certain amount of lubricating oil.

(7) Pay special attention to preventing dust from leaching into the oil seal.