Stop valve selection principle

- Feb 20, 2019-

A shutoff valve is a valve that moves a closure (valve) along the centerline of the seat. Depending on the form of movement of the flap, the change in the seat opening is proportional to the flap travel. Due to the relatively short opening or closing stroke of the valve stem of this type of valve, and the very reliable cutting function, and because the change of the valve seat opening is proportional to the stroke of the valve flap, it is very suitable for the adjustment of the flow rate. Therefore, this type of valve is well suited for use as a cut or adjustment and throttling.

Selection principle

1. The shut-off valve should be used on the pipeline or device of high temperature and high pressure medium. Such as thermal power plants, nuclear power plants, high-temperature, high-pressure pipelines of petrochemical systems.

2. On the pipeline where the flow resistance is not strict on the pipeline. That is, the place where the pressure loss is not considered.

3. Small valves can be used with needle valves, instrument valves, sampling valves, pressure gauge valves, etc.

4, there are flow adjustment or pressure regulation, but the adjustment accuracy is not high, and the pipeline diameter is relatively small, such as the nominal diameter of ≤ 50mm pipeline, should be used.

5. For small chemical fertilizers and large chemical fertilizers in synthetic industrial production, high-pressure angle shut-off valves or high-pressure angle throttle valves with nominal pressure PN160 nominal pressure 16MPa or PN320 nominal pressure 32MPa should be used.

6. In the desiliconization workshop and the easy coking pipeline in the production of alumina Bayer method, it is easy to select the DC type shut-off valve or the DC type throttle valve with the valve body separated, the valve seat can be removed, and the carbide seal pair.

7. In the water supply and heating projects in urban construction, it is known to pass through smaller pipelines, and the cut-off, balance valve or plunger valve can be used, such as the pipeline passing the nominal less than 150mm.