Fault phenomenon and cause analysis of Chengrui valve|Pneumatic single seat control valve not working

Pneumatic single-seat control valve uses compressed air as the power source and cylinder as the actuator, and drives the valve by means of electric valve positioner, converter solenoid valve, retaining valve and other accessories to realize switching or proportional adjustment and receiving. The control signals of the industrial automation control system are used to complete various process parameters such as flow, pressure, temperature, etc. to adjust the pipeline medium.

The characteristics of the pneumatic single-seat control valve are simple control, fast response, and intrinsic safety. No additional explosion-proof measures are required. The following five common fault phenomena occur when the pneumatic single-seat control valve does not operate. Let us analyze the causes of these faults:

Fault phenomenon No signal, no air source.

1 gas source is not open,

2 Because the water source contains ice in the winter, the air duct is blocked or the filter and the pressure reducing valve are blocked.

3 compressor failure;

4 gas source manifold leaks.

Failure phenomenon There is a gas source and no signal.

1 regulator failure,

2 signal tube leakage;

3 positioner bellows leaking;

4 Adjust the mesh diaphragm damage.

Failure phenomenon The positioner has no air supply.

1 filter is blocked;

2 pressure reducing valve failure I

3 The pipe leaks or is blocked.

Failure phenomenon The positioner has a gas source and no output.

The orifice of the positioner is blocked.

Failure phenomenon There is signal, no action.

1 spool is detached,

2 spool is stuck with the society or with the valve seat;

3 the stem is bent or broken;

4 valve seat spool freezing or coke block dirt;

5 Actuator springs rust due to long-term use.

Zhejiang Chengrui Valve Co., Ltd. specializes in the production of pneumatic single-seat control valve, electric single-seat control valve, self-operated control valve, pneumatic shut-off valve and other products, company website:.

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