What is the cause of the non-action of the regulating valve?

What is the cause of the non-action of the regulating valve?

The regulating valve does not work. The symptoms and causes are as follows:

1. No signal, no gas source 1 gas source is not open, 2 due to air source water icing in winter, causing air duct blockage or filter, pressure relief valve blockage failure, 3 compressor failure; 4 gas source manifold leakage.

2. There is a gas source and no signal. 1 regulator failure, 2 signal tube leakage; 3 positioner bellows leakage; 4 regulation mesh diaphragm damage.

3. The positioner has no air supply. 1 filter blocked; 2 pressure relief valve failure; 3 pipeline leakage or blockage.

4. The positioner has a gas source and no output. The orifice of the positioner is blocked.

5. There is signal, no action. 1 spool is detached, 2 spools are stuck with the valve seat; 3 stem is bent or broken; 4 valve seat spool is frozen or coke block dirt; 5 actuator spring is rusted due to long-term use.

Control valve selection

Selection of structural form: steam flow control should select single valve seat; large diameter, large flow, low pressure difference should choose butterfly valve, but the leakage is large at this time; when the medium is high pressure, high pressure regulating valve should be selected; Sewage, prevent valve blockage, optional angle control valve; optional three-way control valve for water volume or water temperature adjustment of heat exchanger.

Selection of regulating valve diameter: When using double-position regulating valve, the valve diameter can be directly selected according to the pipe diameter; in other cases, the valve capacity should be determined according to the maximum flow rate of the medium and the valve pressure drop to calculate the flow capacity Kv value.

上一条信息：：The valve is unstable
下一条信息：Regulating valve flow characteristics selection