Disclosed is a trigger valve methods, use and apparatus. The valve has a housing enclosing, at least in part, a cavity. There is a trigger poppet including a poppet sealing portion at least in part within the cavity, the trigger poppet configured to receive an external input at, or toward, a receiving end thereof. A trigger piston including a primary sealing portion and a major face at least in part within the cavity, the trigger piston configured to receive high pressure fluid therethrough, the trigger piston having a minor face opposite the major surface and a secondary sealing portion. The trigger poppet and trigger piston are biased towards each other at least by the high-pressure fluid acting on the minor face, such that the high-pressure fluid is sealed from the cavity by the poppet sealing portion and primary sealing portion in sealing engagement on each other. The secondary sealing portion sealing against the housing, or part thereof, preventing release of the high-pressure fluid therefrom. The poppet sealing portion when displaced from the primary sealing portion by the external input unseals the sealing engagement and allows high pressure fluid to flow into the cavity and act on the major face causing the trigger poppet to move and unseats the secondary sealing portion from the housing, or part thereof, to allow flow of high pressure fluid to then do work, or cause work to be done.

A depressurisation valve for a cooling system including a main chamber having a main valve, a pilot line having a secondary valve and a blowdown line; the main valve being located to seal a path of the coolant system of the nuclear reactor. The main chamber is connected to the cooling circuit via the pilot line allowing coolant to enter the main chamber, and the blowdown line allows coolant to escape from the main chamber, the pilot line having a lower fluid resistance than the blowdown line. The pressure of coolant in the main chamber maintains the main valve in a closed position, and under elevated temperature and/or pressure conditions fluid is prevented from entering the main chamber via a closure of the secondary valve on the pilot line and reduce the pressure from the valve, moving it to its open position.

A vent valve opens to provide a fluid path from a regulated pressure port to a vent port, a supply valve opens to provide a fluid path from the regulated pressure port to a supply pressure port. A control piston has a linear cam profile with a vent cam that opens the vent valve and a supply cam that opens the supply pressure valve.

A normally closed subplate mounted valve has a lower valve seat defining a function port, an upper seat, and a sleeve between the upper seat and the lower seat. The sleeve defines a first port. The poppet is movable within the sleeve to selectively seal against the lower seat in a piloted position or to seal against the upper seat in an offset position. The poppet blocks the first port when the poppet is positioned in an offset position. A piston shaft is affixed to the poppet for moving the poppet into the piloted or offset position. A spring biases the poppet in the offset position for preventing fluid flow into the first port. A pilot port supplies pressure for sliding the piston to compress the spring and to move the poppet away from the offset position to the piloted position so that fluid may flow into a supply port and out of the function port. A second port may be provided in the sleeve. The ports may be selectively configured for supply or vent. Components may be joined with retainer springs. The piston shaft and poppet connector may be a key and key slot engagement. The ports may be shaped for progressive exposure by movement of the poppet. The poppet may be designed to enable pressure assist through the first port when moving the poppet to the piloted position. The valve seats may be provided with angled sealing surfaces that are angularly offset from their mating counterparts.

A normally closed subplate mounted valve has a lower valve seat defining a function port, an upper seat, and a sleeve between the upper seat and the lower seat. The sleeve defines a first port. The poppet is movable within the sleeve to selectively seal against the lower seat in a piloted position or to seal against the upper seat in an offset position. The poppet blocks the first port when the poppet is positioned in an offset position. A piston shaft is affixed to the poppet for moving the poppet into the piloted or offset position. A spring biases the poppet in the offset position for preventing fluid flow into the first port. A pilot port supplies pressure for sliding the piston to compress the spring and to move the poppet away from the offset position to the piloted position so that fluid may flow into a supply port and out of the function port. A second port may be provided in the sleeve. The ports may be selectively configured for supply or vent. Components may be joined with retainer springs. The piston shaft and poppet connector may be a key and key slot engagement. The ports may be shaped for progressive exposure by movement of the poppet. The poppet may be designed to enable pressure assist through the first port when moving the poppet to the piloted position. The valve seats may be provided with angled sealing surfaces that are angularly offset from their mating counterparts.

A drill string safety valve device (1) has a body (2) with a through-going flow bore (25) and connectors (3, 4) at respective ends (19, 18) for connection to tubulars, such as pipe joints. A valve member (7; 29) is movably arranged in said flow bore (25) and configured for being set in one of two states: a first state of the valve member allows fluid to flow in both directions though the flow bore, and a second state of the valve member allows fluid flow through the flow bore in only one direction. The valve member may be a rotatable ball valve (7) with a through-going flow bore (21).

An integral valve arrangement may comprise a housing. The housing may comprise a main valve and a relief valve. The main valve may comprise an inlet and a first outlet. The relief valve may comprise a relief inlet in a side wall of the inlet, a relief outlet in a side wall of the first outlet, and a pressure relief system. The inlet and the first outlet may be substantially axially perpendicular. The relief inlet and the relief outlet may be substantially axially perpendicular. The pressure relief system may comprise a body abutting walls of the housing, a relief member disposed within the body, and a lever. The relief member may comprise an interior end and an exterior end. The lever may be rotatably coupled to the exterior end of the relief member by a connecting mechanism.

A vent valve opens to provide a fluid path from a regulated pressure port to a vent port, a supply valve opens to provide a fluid path from the regulated pressure port to a supply pressure port. A control piston has a linear cam profile with a vent cam that opens the vent valve and a supply cam that opens the supply pressure valve.

A relief valve has a valve body, a plunger assembly coupled to the valve body for selectively opening and closing the relief valve, and a support member secured to the valve body. A lockout lever is against the support member, forming a vertex. A spring rod is coupled to the lockout lever, and a spring is coupled to the spring rod, providing a bias force against the plunger assembly to normally close the relief valve. In a lockout position, the lockout lever is moved to pivot on the vertex against the support member to further compress the spring, which increases the bias force and, in turn, a cracking pressure of the relief valve.

A relief valve provides pressure relief when a fluid line exceeds a predetermined pressure. The valve includes a body which defines a cavity between inlet and outlet flowpaths. The valve includes a lever arm, which pivots around a pivot point as the valve changes between open and closed positions. A plunger assembly is disposed in the cavity and seals the cavity from the inlet and outlet flowpaths in the closed position. Fluid pressure from the inlet flow path causes the plunger assembly to contact the lever arm to urge the lever arm to rotate. The lever arm engages a spring at a further distance from the pivot point than the plunger assembly, the spring resisting pivoting of the lever arm and urging the valve to remain in the closed position unless a predetermined pressure is exceeded.