Abstract: A non-flowing pilot valve is disclosed having a sense piston assembly (16) and a feedback sleeve (40) co-axially mounted within a valve body (12). A dome-line chamber (32) and an exhaust-line chamber (34) are isolated from each other by a feedback sleeve top shoulder (48) contacting a pop seal (52) on the valve body (12) below set pressure. At a few percentage points of inlet (19) pressure below set pressure, a reseat seal of a foot (20) portion of the sense piston (16) contacts the bottom shoulder (48) of the feedback sleeve (40) thereby closing off the dome-line chamber (32) from below and above and “locking in” dome line pressure. An increase in inlet (19) pressure above set pressure causes the sense piston (16) to move up simultaneously carrying feedback sleeve (40) with it thereby opening the dome-line chamber (32) to the exhaust-line chamber (34) below the open top shoulder (48).

Abstract: A pilot operated safety relief valve (14) has a main piston valve member (60) mounted for reciprocal movement between open and closed positions. The lower end of piston valve member (60) has a seat retainer (87) to retain an annular seat (89) therein. An interchangeable plug (93) is removably connected by bolt (97) to seat retainer (87) and piston valve member (60). Plug (93) extends within the inlet (50) to form a restriction within the inlet (50) defining an angular orifice (99) in the open position of the piston value member (60) for controlling discharge fluid flow. Different size plugs (93, 93A, 93B) as shown in FIG. 4 may be utilized in order to provide the desired orifice size for annular orifice 99 as illustrated in FIG. 4.

Abstract: A pilot operated safety relief valve assembly including a main safety relief valve (14) and a pilot valve (36) connected directly to the relief valve (14) is disclosed. Main safety relief valve (14) has a planar mounting face (76) in contact relation with opposed mating mounting face (78) of the pilot valve (36). Dome ports (72 and 84) in contacting planar faces (76, 78) are in alignment with each other without any tubing therebetween. Exhaust ports (74 and 86) in contacting planar faces (76, 78) are in alignment with each other without any tubing therebetween. Inlet sensing ports (75D, 75E, 65D, 65E) as shown in the embodiments of FIGS. 9 and 10 in contacting planar faces (76D, 76E, 78D, 78E) are in alignment with each other without any tubing therebetween. A fluid pressure pickup fitting (48) has a port (118) which communicates with the fluid passage (50) to the pressure vessel. A test connection (120) is connected to the fluid pressure pickup fitting (48).

Abstract: A safety relief valve (10) having a main valve member (22) in a normally closed seated position has a diaphragm actuator (24) with a dome chamber (34) adjacent the outer side of the diaphragm (26). A pilot valve (28) is in fluid communication with the dome chamber (34) through a dome line (35) for controlling the opening and closing of the main valve member (22). An underdome chamber (40) on the inner side of the diaphragm (26) has an underdome line 44 extending to an underdome control valve (42) for controlling fluid communication to underdome chamber (40) from the inlet (18). An inlet line (48) extends from the inlet (18) to the underdome control valve (42). When the set pressure of the pilot valve (28) is reached, inlet fluid pressure on the inner side of the diaphragm (26) increases while dome pressure in the dome chamber (34) decreases.

Abstract: A safety relief valve (12) for a pressure vessel (10) in which the main valve member (28) includes a valve plate or disc (52) and a retainer plate (64) having a flexible membrane or diaphragm (62) stretched therebetween in a taut relation to provide a frusto-conical shape (FIG. 3) for obtaining bubble-tight sealing against valve seat (26). A fluid chamber (116) is provided between valve plate (52) and retainer plate (64) and inlet fluid pressure is communicated through opening (118) of jack screw (106) to the fluid chamber (116) for providing inlet fluid pressure thereto to force valve plate (52) and retainer plate (64) apart for tensioning of flexible membrane (62) into a frusto-conical shape. A jack screw (106) is threaded within a bushing (94) carried by retainer plate (64). Upon rotation of jack screw (106), valve plate (52) and retainer plate (64) are forced away from each other for tensioning flexible membrane (62) into a frusto-conical shape.

Abstract: A pressure operated safety or relief valve is set forth. It is constructed with a valve body enclosing a movable valve member positioned above a fixed cylindrical structure having a flow passage through it. A coil spring in a bonnet mounted above the valve member bears against the valve member and moves it into closure with a seat on the top of the cylindrical structure. The valve member includes a seal ring for sealing engagement with the seat for closure. When the valve member is opened, the valve member separates to permit pressure flow which then is directed through an annular gap between a surrounding skirt of the valve member and the exterior of a blowdown ring disposed on the cylindrical structure. The valve member snaps open, because with slight opening of the valve member, increased area beneath the valve member is acted upon by the inlet pressure to snap the valve member open.

Abstract: A shuttle valve is described which comprises a valve housing having an inlet and a plurality of outlets. An inner valve assembly is located within an internal cavity which is actuated by a shaft which extends from the internal cavity to a point external from the valve housing. The inner valve assembly comprises a valve disk having a surface which is spherical, at least in part, and a flow elbow, which is located 180.degree. away from the face of the valve disk. The valve disk and the flow elbow are connected to one another and to the shaft. The valve disk is further articulatable. The point which defines the axis of rotation of the shaft and the center point of a phantom sphere defined by the spherical surface of the valve disk, are eccentric, or displaced from one another.

Abstract: A diaphragm controlled spring loaded regulator is disclosed. Such regulator is adapted to regulate the flow of compressed gas applied to a gas blanket on top of liquids in a storage tank and to other low pressure applications. The regulator includes a piston in a valve body with an "O" ring seat contacting an annular seating surface of the valve body. A compression spring is located on one end of the piston and a diaphragm actuator responsive to remote tank pressure is provided on the other end of the piston. At closure, the piston is pressure balanced. One arrangement is provided with a rollout seal in combination with an upper piston part and tapered cylinder walls such that after the piston begins to open, increased opening force is created due to inlet pressure acting on the upper piston part. As the piston begins to close, increased closing force is created due to inlet pressure.

Abstract: An improved pilot valve is disclosed having a flow path from the inlet to the sense cavity via the valve spindle. An articulated disk is provided at the bottom of the valve spindle and is secured thereto by a hollow screw. Such articulated disk can adjust itself to the valve seat below to provide sealing of the valve to the seat in cases where the valve spindle is not perfectly axially aligned with the seat. A spacer between the upper and lower diaphragms is provided for maintenance of proper effective areas of such diaphragms and for prevention of resistance to valve stem motion.

Abstract: A high temperature safety relief system for a pressure vessel (10) including a pilot controlled main relief valve (16) and an associated non-flowing pilot valve (34) with high temperature metal or metal like seals for temperatures as high as around 1,000.degree. F. provided for both the main relief valve (16) and pilot valve (34). The main valve body (26) has a main body chamber (48) in fluid communication with the inlet flow passage (45) when the reciprocal piston valve member (88) is in seated closed position. The movement of the piston valve member (88) is cushioned during movement to open position and during movement to closed position. The non-flowing pilot valve (34) has an elongate internal housing (204) receiving the inlet line (36) along its longitudinal axis and the housing (204) is mounted for external rotational adjustment to control the blowdown pressure.

Abstract: A high temperature safety relief system for a pressure vessel (10) including a pilot controlled main relief valve (16) and an associated non-flowing pilot valve (34) with high temperature metal or metal like seals for temperatures as high as around 1000.degree. F. provided for both the main relief valve (16) and pilot valve (34). The main valve body (26) has a main body chamber (48) in fluid communication with the inlet flow passage (45) when the reciprocal piston valve member (88) is in seated closed position. The movement of the piston valve member (88) is cushioned during movement to open position and during movement to closed position. The non-flowing pilot valve (34) has an elongate internal housing (204) receiving the inlet line (36) along its longitudinal axis and the housing (204) is mounted for external rotational adjustment to control the blowdown pressure.

Abstract: A high temperature safety relief system for a pressure vessel (10) including a pilot controlled main relief valve (16) and an associated non-flowing pilot valve (34) with high temperature metal or metal like seals for temperatures as high as around 1,000.degree. F. provided for both the main relief valve (16) and pilot valve (34). The main valve body (26) has a main body chamber (48) in fluid communication with the inlet flow passage (45) when the reciprocal piston valve member (88) is in seated closed position. The movement of the piston valve member (88) is cushioned during movement to open position and during movement to closed position. The non-flowing pilot valve (34) has an elongate internal housing (204) receiving the inlet line (36) along its longitudinal axis and the housing (204) is mounted for external rotational adjustment to control the blowdown pressure.

Abstract: A safety relief system for a valve in a vent or a main flowline. The safety relief system utilizes a main actuator (24) utilized primarily for a positive pressure condition and a vacuum actuator (96) in axial alignment with the main actuator (24) utilized exclusively for a negative pressure condition. The main valve member (18) has a stem (22) which extends within both actuators (24, 96) and diaphragms (26, 100) are connected to the stem (22) for movement of the valve member (18).

Abstract: In the preferred and illustrated embodiment, a safety relief valve, subject to control of redundant pilot valves with a control system, is set forth. A safety relief valve is ordinarily installed in a fail safe circumstance; accordingly, this control system incorporates redundant pilot valves which respond independently of one another having outputs utilized in the control system to trigger operation of the safety relief valve. The control system has, in its preferred form, an elongate body mounting redundant pilot valves on common manifold passages. If any pilot valve forms a signal requiring operation of the safety relief valve, that signal for the safety relief valve adjusts the setting of the safety relief valve.

Abstract: For use with a safety relief valve, a pilot valve is disclosed. The preferred and illustrated embodiment of the pilot valve incorporates a pressure moved spindle within a housing, the housing being drilled and incorporating a valve and valve seat mechanism. The device is adapted to be connected to a high pressure inlet source. In addition, it has a flow path from the inlet through a needle orifice. This needle orifice chokes the flow into an outlet port. The outlet is provided for controlling a safety relief valve. A third path past the valve element is included which conducts fluid to an exhaust port. A coil spring forms a force in one direction for the valve element while the inlet line pressure forms a force in the opposite direction. When the inlet pressure is sufficiently high, the valve element is moved, thereby opening the valve.

Abstract: A vacuum-type holder (10) for retaining fragile articles such as semiconductor wafers (16) during a manufacturing operation, such as an electrolytic treatment includes a vacuum-operated support (36) at each of the seats (23) which exerts a supporting force against the underside (32) of the wafer (16) which is opposite to and proportional to a vacuum generated holding force which urges the wafer against the seat. The supporting force, consequently, minimizes bending stresses to which the wafer (16) could otherwise be subjected.

Abstract: In the preferred and illustrated embodiment, a low pressure safety relief valve and pilot for the safety relief valve is particularly adapted for use with steam. The pilot incorporates two diaphragms, one being a sense diaphragm responding to a pressure setting opposed by an adjustable spring, and the second being a boost diaphragm which assists opening of the pilot to a fully open position. The pilot includes an inlet supply passage communicating first through an adjustable and then a fixed orifice to define controllable pressure drops, and forms a control pressure applied to the dome of the safety relief valve. The dome pressure closes a movable piston, subject to differential areas. The safety relief valve is opened by dropping dome pressure at such time as the safety relief valve is controllably opened. The pilot valve, being equipped with a sense diaphragm and selectively boosted by a differential force acting across the boost diaphragm, drops the dome pressure, by venting to atmosphere.

Abstract: A safety pressure relief device for a refrigerated liquified gas storage vessel having a large diameter valve seat mounted on the vessel, a valve closure movably mounted to engage the valve seat to close flow therethrough and to move away from the valve seat to relieve pressure in the vessel, a spindle extending through the seat and guided by a spider spanning the seat, a spring within the vessel biasing the valve closure toward the seat and means of preselected strength retaining the valve closure on the seat unitl a preselected maximum desired fluid pressure is reached within the vessel at which time such retaining means fails and valve closure moves to open position to provide large area relief of fluid pressure from the vessel.