Common faults and elimination methods of pressure reducing valves

1.No decompression effect 

(1)Fault phenomenon: No decompression effect (decompression valve failure). 

Cause analysis: The spool of the pressure reducing valve is stuck at the fully open position. 

Elimination method: overhaul or replace the pressure reducing valve, check the hydraulic oil quality.

(2)Symptoms of failure: no decompression effect (cone valve failure). 

Cause analysis: The elastic coefficient of the pressure regulating spring is too large. 

Elimination method: replace the pressure regulating spring.

2.System pressure fluctuation 

(1)Failure phenomenon: system pressure fluctuation (decompression valve failure). 

Reason analysis: ① The geometric accuracy of the valve core of the pressure reducing valve is poor; ② The elastic coefficient of the spring of the pressure reducing valve is too small; ③ The damping hole is sometimes blocked and sometimes open. 

Elimination method: ① Replace the pressure reducing valve; ② Replace the spring; ③ Clean the damping hole.

3.The system pressure cannot be increased

(1)Symptom: The system pressure cannot be increased (decompression valve failure). 

Cause analysis: The pressure relief valve leaks. 

Elimination method: check and replace the sealing element of the pressure reducing valve.

(2)Fault phenomenon: the system pressure cannot be adjusted up (cone valve fault). 

Cause analysis: The elastic coefficient of the pressure regulating spring is too small. 

Elimination method: replace the pressure regulating spring.