A valve body has a piston that slides within the body through four successive positions. The piston has a head, and an upper and lower skirt, with a port in the upper skirt. In the first position, a bias force urges the piston to the first of four positions, in which the piston port is closed. In a second position, the piston port aligns with a low pressure port in the valve body, when a low pressure supply of water is connected. In a third position, greater pressure again closes the piston port. In a fourth position, at a still greater pressure, the piston port aligns with a high pressure port in the valve body. The bias force or a location of the piston port can be varied for valves along a supply line, whereby varying supply pressure opens different valves, thereby enabling addressing of valves according to supply pressure.

A valve for pressurized gas or chemical agent. The valve comprises: a body with: an inlet, an outlet, and a passage which connects the inlet with the outlet and which includes a seat]. The valve further comprises a sliding piston able to engage with the seat in order to close the passage and a telescopic extension sliding against the passage in order to guide the piston in the passage at least between the open position and the closed position. The pressure difference between opposite faces of the piston pulls away the piston and the telescopic extension from the seat in order to open the passage, the passage remaining closed under pressure equilibrium. Additionally, a fire extinguishing system.

A low pressure regulator for a high pressure fuel pump includes a standard damping orifice, providing a constant level of piston movement damping by enabling a fluid pathway between a spring chamber and a return line. The low pressure regulator also includes a further damping orifice, which is covered by the piston when discharge port holes are open, the further damping orifice providing a further, variable level of piston movement damping by providing a further fluid pathway between the spring chamber and return line. The further damping orifice is open in a hydraulic accumulator mode and closed in a regulator mode, thereby reducing pressure spikes caused by insufficient spring chamber filling.

Methods and systems are provided for a zero hysteresis valve. In one example, a valve comprises protrusions shaped to maintain a distance between a moveable portion of the valve and a valve seat.

A first valve mechanism is a valve mechanism provided in a flow path coupled to a liquid ejecting head that ejects a liquid, and including a valve that opens/closes the flow path, a first communication liquid chamber that communicates with the flow path, and a first pressure receiving body that converts a pressure difference between a pressure of the first communication liquid chamber and a reference pressure into an operating force of the valve, in which a threshold pressure of the first communication liquid chamber for determining opening/closing of the valve is variable.

A pressure relief valve for a two-phase immersion cooling system is configured to support fluid flow rates up to 500 cfm, 550 cfm, 600 cfm, or even 2000 cfm. This, in turn, allows the cooling system to support computing systems with a power density greater than 250 kW. This is accomplished by the valve having a relatively large passage (e.g., 2-6 inch diameter), a relatively large spring (e.g., 1.5-1.7 inch diameter), and a guide rod rigidly coupled to the poppet and slidably coupled to a guide plate. The valve may be used as an outlet valve and coupled to an adsorbent chamber to reduce the loss of coolant from the system as air is vented to an ambient environment. The valve may be used as an inlet valve and coupled to an adsorbent chamber to reduce the intake of water vapor as air from the ambient environment flows into the system.

A pressure control system configured to respond to high-pressure conditions in a fluid conduit is disclosed. The system generally includes first and second flow restrictors positionable inline on a fluid conduit and configured to block fluid flow in the conduit and respond to a high-pressure event to allow fluid flow therethrough. The first flow restrictor is position upstream from the second flow restrictor and may open to allow fluid flow in response to the high-pressure event. The second flow restrictor provides adjustable flow of fluid therethrough or may open a bypass line in response to the high-pressure event to allow unrestricted fluid flow therethrough.

In a high-pressure pump, a relief valve main body has a rod shape. A relief valve seat portion is integrated with an end of a relief valve main body so as to be capable of contacting a relief valve seat. The relief valve main body is inserted into a guide hole portion of a support portion. The guide hole portion slidably supports an outer wall of the relief valve main body so as to guide a reciprocating movement of the relief valve main body in the axial direction. A fuel guide portion is provided at an end portion of the relief valve main body facing the pressurizing chamber and can guide a flow of the fuel in a direction radially outward of the relief valve main body on the way from the pressurizing chamber toward the valve seat portion.

A new type of pressure relief valve is described herein which has advantages over standard valves in that it may comprise a longer plunger than normal, and two guiding points located far away from each other for guiding the plunger within the housing. The valve may also comprise improved exhaust ports and an anti-rotation washer.

A back pressure balanced relief valve can include a piston, a pressure balancing device, and a pressure sensor. A pressure chamber can be created between the pressure balancing device and the piston. The pressure sensor can be configured to monitor the pressure in the pressure chamber for indications of a potential failure of the balancing device.