Fault and Repair of Flow Control Valve

Fault and Repair of Flow Control Valve

The flow control valve is used to control the flow of liquid in the hydraulic system to control the movement speed of the actuator. Flow valves include throttle valve, speed regulating valve, overflow throttle valve, diversion and collection valve and single flow stabilizing valve.

Common faults of flow control valve

The characteristic of the flow control valve is to control the oil flow by changing the size of the throttle port (throttle gap) under a certain pressure difference and ensure smooth operation. This type of valve has a high failure rate in the low speed and small flow regulation section, because the orifice in the low speed section is small, it is sensitive to the cleanliness of the oil, and has strict requirements on the internal structure and base sealing, and requires a stable speed regulation. The common faults of flow control valve mainly include flow regulation failure, unstable flow and too large internal leakage. The main reasons are that the valve core is clamped radially and the adjustment device fails, the oil is dirty, the installation is improper, the tightness of the tightening screws is uneven or too tight, which makes the valve body deformed, which may cause the valve core to be clamped radially and make the adjustment fail. The production flow may be unstable if the locking device is loose, the throttle port is blocked, and the oil inlet and outlet are inversely connected. The slide valve sealed by the clearance is excessively worn, which increases the internal leakage and also causes unstable flow.

Repair of the flow control valve

According to the fault phenomenon of the flow control valve, find out the cause of the fault and then repair it. Check the geometric accuracy of valve core and valve sleeve. If the clearance is too small, grinding repair shall be carried out to avoid jamming. If the gap is too large, brush plating technology can be used to repair the valve core. The valve core and seat with poor sealing shall be ground. If the spring is deformed or broken, it should be corrected or replaced.