FLOW CONTROL VALVES

摘要

In one embodiment, a flow control valve includes a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity with first and second chambers. The valve further includes a hollow piston disposed in the first chamber and a seal separating the first and second chambers. The seal has a section within the piston that is exposed to the fluid in the first chamber. The section of the seal defines a first effective area. The valve also includes a biasing member configured to urge the piston, and a reference pressure passageway in fluid communication with the inlet and the second chamber. The valve can further include a piston seat that has a second inner effective area at least approximately equal to the first inner effective area.