Patent ID: 8091582

Claim:
A system for hydraulically managing fluid pressure downstream of a main valve between a preselected upper pressure set point and a lower pressure set point, comprising: a main valve having a fluid inlet and a fluid outlet, the main valve being configured to open to increase fluid flow therethrough, and to close to reduce fluid flow therethrough; a variable orifice assembly coupled to the main valve such that the flow area of the variable orifice changes as the main valve position changes; a fixed orifice in fluid communication with an outlet of the variable orifice, wherein the fixed orifice is not in the fluid pathway of the main valve; and a control device operably associated with the main valve, an inlet of the fixed orifice and an outlet of the fixed orifice and configured to detect pressure differentials between the inlet and outlet of the fixed orifice and open and close the main valve in response to the detected pressure differentials.