Common Problems and Solutions: Pressure Reducing Valve Operating Instructions

Pressure-reducing valves are key components in fluid systems, responsible for reducing high pressure fluids to the required low pressure to ensure stable system operation. However, there are a number of common failures that can occur during the use of a pressure reducing valve. This article will address these failures, provide concise and clear solutions to help users better understand and maintain the pressure reducing valve.
First, the outlet pressure is almost equal to the inlet pressure, no pressure reduction
Failure performance: the pressure reducing valve import and export pressure is very close, or even equal, and the export pressure does not change with the pressure regulating handle rotation.
Causes and solutions:
The main valve spool is stuck:
Reason: the main valve spool or valve body hole has burrs, or gap stuck with dirt.
Solution: Remove burrs, clean the valve hole and spool, and repair the accuracy.
The fit is too tight:
Cause: The main valve spool and the valve hole fit too tight, or the assembly of the hair.
Solution: Check and adjust the fit clearance, and grind the valve hole and spool if necessary.
Damping hole clogged:
CAUSE: Damping holes are clogged with dirt.
Solution: Use steel wire or compressed air to blow through the damping hole, clean and reassemble.
Oil drain hole not screwed out:
CAUSE: Drain hole oil plug not unscrewed.
SOLUTION: Unscrew the oil drain plug to ensure smooth drainage of oil.
The valve cover is assembled in the wrong direction:
Cause: The valve cover is assembled in the wrong direction.
Solution: Check the direction of valve cover assembly to ensure correct installation.
Second, the outlet pressure is very low, can not be raised
Failure performance: the outlet pressure of the pressure reducing valve is very low, even if you tighten the regulator handwheel can not be raised.
Causes and solutions:
The inlet and outlet ports are reversed:
Cause: Mounting plate design error or take over the wrong.
Solution: Check and correct the inlet and outlet connections.
Inlet port pressure too low:
Cause: Insufficient pressure upstream of the pressure reducing valve.
Solution: Identify the cause of low upstream pressure and repair.
Downstream circuit load too small:
CAUSE: Downstream load is too small to build up pressure.
SOLUTION: Increase the load by connecting a throttle valve in series downstream.
Poor contact between pilot valve and seat:
CAUSE: Dirt retention or scratches.
Solution: Clean pilot valve and seat and repair mating surfaces.
Damping hole clogged:
Cause: Damping holes are clogged with dirt.
Solution: Clean the damper hole to ensure it is clear.
Spring problem:
CAUSE: Misassembled, fatigued or broken spring.
Solution: Replace the qualified spring and adjust the pre-compression.
Pressure regulating handle problem:
CAUSE: Strained regulator handle threads or insufficient effective depth.
SOLUTION: Inspect and replace damaged parts and adjust effective depth.
Poor sealing:
CAUSE: O-ring leakage, damage or compression screw not tightened.
Solution: Check and replace the O-ring, tighten the pressure screw.
Third, does not stabilize the pressure, pressure oscillation, sometimes noisy
Failure performance: the outlet pressure of the pressure reducing valve is not stable, there are large fluctuations, and sometimes even accompanied by noise.
Causes and solutions:
Pilot-operated pressure reducing valve problem:
Reason: Pilot valve and relief valve commonality caused by the failure.
Solution: Refer to the troubleshooting and repair method of the relief valve.
Use in excess of rated flow rate:
CAUSE: Pressure reducing valve is used under conditions exceeding the rated flow rate.
Solution: Use a pressure reducing valve of suitable model specification.
High back pressure at the drain port:
Cause: Excessive back pressure at the drain port.
Solution: Ensure that the drain line is returned separately to reduce the back pressure.
Spring problem:
Cause: Deformed spring or poor stiffness.
Solution: Replace the qualified spring.
Fourth, the working pressure adjustment after the outlet pressure rises on its own
Failure to perform: The outlet pressure of the pressure reducing valve will rise on its own if the outlet flow rate is zero after it is regulated.
Reason and solution:
Main spool leakage:
Cause: The main spool fits too loosely or wears too much.
Solution: Regularly check and replace parts that are badly worn to ensure sealing performance.
Summarize
Pressure reducing valves may encounter a variety of failures in the course of use, but as long as we understand its working principle and the causes and solutions of common failures, we can effectively avoid and solve these problems. The following are some suggestions:
Regular inspection and maintenance: Regularly inspect and maintain the pressure reducing valve to ensure its normal operation.
Select the right model: Select the right model and specification of the pressure reducing valve according to the actual demand.
Correct installation and use: Install and use the pressure reducing valve correctly according to the instructions to avoid malfunction caused by improper operation.
Pay attention to sealing performance: When designing and installing pressure reducing control circuits, fully consider the importance of sealing performance.
By following the above recommendations, we can ensure the stable operation of the fluid system and extend the service life of the pressure reducing valve. We hope this article can provide users with useful reference and help!