Abstract: A relief valve device having a spring, a valve bonnet, a valve stem, a disc holder, a valve disc, a huddling chamber, a blowdown ring, and a nozzle. In the valve device, the valve disc is positioned above the nozzle; the spring is disposed in the valve bonnet; the spring surrounds the valve stem such that a longitudinal axis of the spring and a longitudinal axis of the valve stem are coaxial; the disc holder surrounds an outer periphery of the valve disc and is adjacent and in direct contact with a surface of the valve disc around an entire perimeter of the valve disc; the blowdown ring is disposed at a top section of the nozzle; a bottom section of the nozzle is connected to a bottom surface of a valve body and the top section of the nozzle is connected to the valve disc; and the disc holder is filled with oil.

Abstract: An improved deflator valve is described herein. The deflator valve has a main body with one or more ports, one or more vents, or port or vent slots for introducing air into or relieving pressure from within the main body in a vortex, circular flow. The deflator valve also includes a piston having an O-ring disposed around an outer circumference of the piston. The O-ring of the piston and the ports and vents are effective for reducing noise and deflation time and improving accuracy and ease of adjusting a pressure setting. The deflator valve can further include a dual or variable rate spring that can achieve an extensive destination pressure range. The deflator valve can also include a threadless lead in, fewer valve stem threads, or a lock chuck for enhanced valve stem attachment methods.

Abstract: A method of shutting down operation of a fuel cell system comprising a fuel cell stack, the method comprising the sequential steps of: i) ceasing a supply of fuel to the fuel cell stack; ii) closing a shut-off valve on an exhaust line in fluid communication with a cathode system of the fuel cell system, the cathode system comprising a cathode fluid flow path passing through the fuel cell stack; iii) pressurising the cathode system with an air compressor in fluid communication with a cathode air inlet port in the fuel cell stack; and iv) ejecting water from the cathode flow path.

Abstract: A pressure relief device usable in a high-pressure fluid circuit for limiting the pressure in the case of a failure of a circuit component is provided, the device includes a body with a pusher sliding therein and axially movable by a spring. A ball seals an orifice connecting a chamber receiving a high-pressure fluid and another chamber. The other chamber includes at least one fluid discharge opening and the ball being held by the spring in a position closing the orifice below a predetermined pressure. The pusher devoid of axial through channels for the fluid, slides in the body and closes at least partially each discharge opening. At least one of discharge openings is connected to an opening also embodied in the body and open at least partially to the opposite side of the pusher.

Abstract: A pressure control system for controlling pressure in a tank is provided. The pressure control system includes a pressure relief valve and a rupture disc subassembly. The pressure relief valve is connected to the tank. The rupture disc subassembly is located between the pressure relief valve and the tank and is connected to the tank. The pressure relief valve is connected such that removal of the pressure relief valve does not affect the connection of the rupture disc subassembly to the tank.

Abstract: For operating pumps above the respective system resistance for all volume flows, for a spring-loaded, directly acting overflow valve for limiting the pressure in a system in which a liquid is lifted by a positive-displacement pump and flows through the system with varying rates of flow, the valve chamber (1) and the valve body (22) with the valve head (14) placed therein are constituted in such a way that the valve head, after lifting off from the valve seat (3), has a second active diameter which is bigger than the first active diameter, whereby the valve head (11) simultaneously releases, with increasing stroke of the valve body (22), an enlarging flowing-through cross section, whereby the valve body (22) is constituted in one part as a valve piston (11) sliding in the valve chamber (1) with a third active diameter which is bigger than the second active diameter so that the liquid flowing through the valve chamber (1), the valve being opened, produces a pressure difference which acts onto the valve piston (

Abstract: A diaphragm/spring operated pressure relief valve having a sensing passage of substantially the same flow area as the outlet orifice of the valve whereby failure of either diaphragm results in "fail open" configuration. In addition the effective area of the balancing diaphragm is substantially the same as the seat area of the seat seal of the outlet orifice such that a pressure or vacuum on the valve outlet pushes or pulls equally on the balancing diaphragm and the valve seat seal thereby balancing the forces and keeping the valve stable.

Abstract: In a pressure relief valve, a valve body is provided with an axial bore counterbored from each of its ends to form an inlet port for connection with a container of gas to be monitored and for receiving a valve assembly at its other end opening the valve axial bore in response to the valve being unseated by a predetermined pressure in the container. The valve assembly includes a piston-type valve normally seated in the bore by a collapsible strut or pin interposed between the valve and a plug member secured to the downstream end portion of the valve bore.

Abstract: The present invention comprises a valve body (24) with an inlet (28) and an outlet (30), and an inlet-closing poppet (32) moveably disposed within a chamber (26) in the valve body, the poppet incorporating a piston head (34) whose face (36) opposes the inlet and from which projects a plug (62) for closing-off the inlet (28) from the remainder of the piston face (36) when the poppet is at its inlet-closing position. A spring (54) urges the poppet towards its inlet-closing position with sufficient force to keep the inlet closed until the fluid reaches a preselected cracking pressure, whereupon the spring allows the poppet to be displaced slightly, exposing the remainder of the piston face to the fluid. The action of the fluid on the piston face is then sufficient to drive the poppet fully back to an annular stop (60) provided within the valve body whose engagement also serves as a partial seal about the periphery (70) of the piston.

Abstract: A fluid pressure relief valve provides automatic venting of a high pressure source to an area of lower pressure in response to pressure build-up of the source. The valve includes a valve body in which a recess is provided, a passage providing communication between one end of the recess and the source. A poppet is oriented for movement with respect to the recess and includes a sealing element adapted to close the other end of the recess by sealing engagement with the valve body. A spring urges the poppet toward sealing engagement. The poppet has ports proximate the sealing element which are covered when the sealing engagement is maintained but are uncovered progressively with movement of the poppet out of sealing engagement. If the source pressure exceeds a predetermined threshold level, the poppet is driven increasingly away from the sealing engagement with increase in pressure of the source for progressively uncovering the ports in response to dynamic impact upon the poppet by fluid flow through the valve.

Abstract: A chamber in a valve case has an inlet port of exhaled air in one of its end walls. Spaced inwardly from the side wall of the chamber is a valve seat surrounding the inlet port and engaged by one side of a sealing member, the opposite side of which is engaged by a rigid disc secured to a valve stem that extends through the port and into guiding means for the stem. The diameter of the disc is nearly as great as the diameter of the chamber. A spring in the case is compressed between the disc and the other end wall of the valve chamber for pressing the sealing member against the seat. The disc is spaced from the ported wall of the chamber far enough for the marginal portion of the disc that extends laterally out beyond the sealing member to be inclined toward the ported wall but spaced from it.