Pump oil leakage makes a large amount of hydraulic energy into heat energy, which promotes the increase of oil temperature and deterioration of working conditions. The oil leakage of the gear pump can be divided into two types: internal leakage and external leakage. Internal leakage reduces the output flow of the pump and the pressure rise is not high, and external leakage pollutes the environment in addition to the above disadvantages, so reduce internal leakage and avoid Leakage. The method to reduce internal leakage is to properly adjust the movement gap of the pump. If the gap is too large, the internal leakage will increase; if the gap is too small, the friction will increase. Causes of leakage:
1) The oil return holes on the front and rear pump covers are blocked, or this hole is not drilled through during processing. This requires cleaning or drilling through.
2) The pump cover and seal ring cooperate too loosely to form oil leakage, which can be solved by adjusting the gap.
3) The lip of the shaft seal is scratched by the keyway of the main shaft or the skeleton spring comes off. This can replace the oil seal or reinstall.
4) The sealing surface of the parts is severely scratched. The sealing surface should be re-examined to eliminate scratches.
5) The inner diameter of the groove of the oil seal is too small or the chamfer of the groove is too small, so that the oil seal is inclined, resulting in oil leakage. The size of the groove should be checked, and the groove or chamfer should be processed as specified.
6) The chamfer of the shaft is too rough or the chamfer is too small, so that the lips of the seal are rolled, and the roughness or chamfer should be checked. During assembly, grease should be applied to the chamfers.
7) If the seal is used for a long time under high temperature, or the seal is not good in gel, or the assembly is improperly lost due to elasticity, the seal must be replaced.
During installation, the pump body is reversed, and the oil outlet is connected to the unloading groove. Or in the trial rotation, the steering is wrong, the oil seal on the shaft is broken down, causing leakage. This is because the oil inlet of the pump is connected to the oil seal through the oil return channel. When the pump is reversed, the oil inlet becomes an oil outlet, and the pressure oil breaks through the oil seal through the oil return channel or flushes the oil seal out of the pump body to form an external leak. This should correct the pump steering and replace with a new oil seal.
