reason
1 Oil cylinder oil seal is worn or damaged
2 The priority valve is excessively worn.and the clearance between the valve stem and the valve body exceeds the specified value
3 Oil leakage in piping system
4 Severe internal leakage of working oil pump
5 Improper adjustment of safety valve, low system pressure
6 Blockage of suction pipe and filter
Method of exclusion
1 Change the oil seal
2 Disassemble and repair, make the gap reach the specified value or replace
3 Find the oil leak and clean it
4 Replace the working oil pump
5 Adjust the working pressure of the system to the specified value
6 Clean the filter and change the oil