Gas unit with pressure regulator - has servo controlled stage with safety valves for full isolation

摘要

The gas unit has an inlet (12) and outlet (14), with the gas pressure regulating stage (16) located in between. The regulator has first (18) and second (20) safety valves, each of which has a solenoid actuator (30,42) and a poppet (22,34) Regulation of the output pressure is controlled by displacement of a spool (60) that is displaced dependent upon the pressuree differential. The lower end carries a diaphragm actuator (72) that provides a servo actuation to control the connection between the input (48) and output (50) chamber.