Conventional Methods for Establishing Control Valve Pressure Drop In general industrial applications, control valve pressure drop has commonly been established by one of the three methods ...

This design is intended to yield a longer service life of these valves. However, as the plant ages, this design also can yield a severe modulation, or “hunting,” in these valves.

Typically, one of the two valves is a gate valve, and the other is commonly a stop-check valve. In lower pressure/temperature applications, a solid wedge gate valve can be used, while a flexible wedge ...