Pump oil leakage converts a large amount of hydraulic energy into thermal energy, causing an increase in oil temperature and deterioration of working conditions. The oil leakage of gear pumps can be divided into two types: internal leakage and external leakage. Internal leakage reduces the output flow rate of the pump and prevents pressure rise, while external leakage not only causes the above problems but also pollutes the environment. Therefore, it is necessary to reduce internal leakage and avoid external leakage. The method to reduce internal leakage is to adjust the movement clearance of the pump appropriately. If the clearance is too large, internal leakage will increase; The gap is too small and the friction increases. Causes of leakage:

1. The return oil holes on the front and rear pump covers are blocked or not drilled through during processing. This requires cleaning or drilling.

2. Loose fit between the pump cover and sealing ring can cause oil leakage, which can be solved by adjusting the clearance.

3. The shaft seal lip is scratched by the spindle keyway or the skeleton spring falls off. This can be replaced with a new oil seal or reinstalled.

4. The sealing surface of the parts is severely scratched. Re study and eliminate scratches on the sealing surface.

5. The inner diameter of the oil seal groove is too small or the groove chamfer is too small, causing the oil seal to tilt and leading to oil leakage. The size of the groove should be checked, and the groove should be processed according to the regulations or reversed

6. If the chamfer of the shaft is too rough or too small, causing the lip of the seal to curl, the roughness or chamfer should be checked. During assembly, grease should be applied to the chamfers.

7. Seals that have been used for too long at high temperatures, or have poor adhesive properties, or have lost elasticity due to improper assembly causing leakage, must be replaced.