Abstract: A control device includes a pressure-displacement transducer for triggering a control part for activating a safety valve of a pressure vessel. A space in the pressure-displacement transducer can be connected to a blow-off tank through a drainage line. A first embodiment includes a switchover valve device which is associated with the drainage line and connects the space to a take-off line instead of to the blow-off tank when the pressure in the blow-off tank is above a limiting pressure. A second embodiment includes a hydraulic compensating system which exerts a first force on the pressure-displacement transducer, from a pressure in the blow-off tank. That force counteracts a second force produced in the space by that pressure and in particular compensates for that force.

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 control valve assembly including a no-bleed pilot valve is disclosed. The pilot valve includes a pressure responsive valve adapted to move in connection with a control parameter, such as downstream fluid pressure. The pressure responsive valve selectively connects certain ports with upper and lower chambers of a control valve actuator so that the upstream and downstream fluid pressures may be used to operate the actuator.

Abstract: A pressure-control valve (1) comprises a first control piston (1), which is disposed between a first pressure chamber (6), which adjoins the first control piston (1) and is connected to at least one working line (A, B), and a second pressure chamber (7), which adjoins the first control piston (1) and is pushed against a stop (3) by a first preloading spring (4). A throttle (8) connects the first pressure chamber (6) and the second pressure chamber (7). The second pressure chamber (7) is connected to a second control piston (11), which is preloaded by a second preloading spring (17) and which, when a predetermined pressure in the second pressure chamber (7) is exceeded, is displaced to an extent such that a control edge (12) of the second control piston (11) clears a connection of the second pressure chamber (7) to a hydraulic fluid discharge point (23).

Abstract: In a rotary metering valve, a metering block is located in a chamber having a plurality of outlets. The metering block is connectable to a fluid supply and has an outlet selector rotatable to select one of several different outlets from the block to the chamber. A barrier extends between the wall of the chamber and the metering block to prevent fluid flowing in a 360 degree rotary motion around the block. A sprayer check valve is also disclosed. The valve has a diaphragm acted on by control fluid whose pressure is set to just below the spray fluid pressure and which is varied according to variations in the spray fluid pressure.

Abstract: The present invention relates to an adaptable controller for controlling environmental systems, and more particularly to an improved computer-controlled irrigation and lighting system. Scheduling is selected using a unique graphical user interface and is transmitted to the controller remotely. Sensing devices for water flow to determine leaks and calculate usage using venturi are provided which communicate with the controller to adjust output in real time based on the measurements.

Abstract: A valve control apparatus for generating an anticipatory output response for controlling a fluid flow in a fluid flow line includes a valve provided inside the fluid flow line, at least one sensor for providing at least one input signal, the at least one input signal responsive to properties of the fluid flow in advance of the valve, and a letdown back-pressure controller receiving the at least one input signal and providing a tunable output signal for selectively opening and closing the valve to vary flow in the flow line responsive to the at least one input signal.

Abstract: A control device includes a pressure-displacement transducer for triggering a control part for activating a safety valve of a pressure vessel. A space in the pressure-displacement transducer can be connected to a blow-off tank through a drainage line. A first embodiment includes a switchover valve device which is associated with the drainage line and connects the space to a take-off line instead of to the blow-off tank when the pressure in the blow-off tank is above a limiting pressure. A second embodiment includes a hydraulic compensating system which exerts a first force on the pressure-displacement transducer, from a pressure in the blow-off tank. That force counteracts a second force produced in the space by that pressure and in particular compensates for that force.

Abstract: A pressure relief system includes a relief valve for selectively discharging process media from a pressure vessel, a pilot valve for controlling the relief valve, and an isolation system for isolating the pilot valve from the process media. The pilot valve has an inlet port, a control port in communication with a dome chamber of the relief valve, and a discharge port. The isolation system includes an accumulator such as a piston-type or bladder-type accumulator, a source of pressurized control fluid, a pressure regulator, and a check valve. The accumulator has an interior chamber with an inlet in communication with an inlet of the relief valve and an outlet in communication with the inlet port of the pilot valve. An isolator such as a piston or bladder divides the interior chamber into a first portion and a second portion and prevents flow therebetween to isolate process media (located in the first portion) from control fluid (located in the second portion).

Abstract: A water purifier generally associated with a beverage dispenser is disclosed. The water purifier includes a conduit having a first end and a second end opposite to the first end, and a water purifying device disposed in the conduit between the first and second ends thereof. The first end of the conduit is arranged to conduct water to be purified into the conduit, and the second end of the conduit is arranged to conduct the purified water from the conduit to a location outside of the water purifier. A flow of the water through the conduit is completely prohibited by the cooperative operations of a pressure detector at the second end of the conduit and an electromagnetic valve at the first end of the conduit at a time when the water attempts to flow through the conduit from the second end to the first end.

Abstract: A valve control apparatus for generating an anticipatory output response for controlling a fluid flow in a fluid flow line includes a valve provided inside the fluid flow line, at least one sensor for providing at least one input signal, said at least one input signal responsive to properties of said fluid flow in advance of said valve, and a letdown back-pressure controller receiving said at least one input signal and providing a tunable output signal for selectively opening and closing said valve to vary flow in the flow line responsive to said at least one input signal.

Abstract: In a vacuum pressure control system constituted of a vacuum vessel, a vacuum pump sucking gas in the vacuum vessel, a vacuum proportional opening and closing valve disposed on a pipe connecting the vacuum vessel and the vacuum pump, the vacuum proportional opening and closing valve changing its opening to change the vacuum pressure in the vacuum vessel, a pressure sensor to measure the vacuum pressure in the vacuum vessel and a vacuum pressure control device to control the opening of the vacuum proportional opening and closing valve based on the output of the pressure sensor, the vacuum proportional opening and closing valve is provided with a valve seat, a valve member with a tapered surface in its outer periphery and a pilot valve, the valve member being movable along a center line of the valve seat to change a clearance area between the valve seat and the tapered surface, and the vacuum pressure control device controls a servo valve to change the pressure of air to be supplied to the pilot valve based on t

Abstract: A positioner and method for generating an output signal for setting a controlled object to a control condition corresponding to an input signal, including a memory unit for storing a conversion relation for converting the input signal to a command signal; a signal conversion unit for converting the input signal to the command signal based on the conversion relation; a control unit for generating the output signal for controlling the controlled object corresponding to the command signal; and a setting unit for adjusting the command signal to obtain a desired control condition for each of a plurality of selected input signals, thereby generating a modified conversion relation between the input signal and the command signal. The modified conversion relation generated by the setting unit is stored in the memory unit as the conversion relation.

Abstract: A pilot operated safety relief valve (14) in which a pilot valve (32) controls the opening and closing of the main valve member (26). The pilot valve (32) has a spindle valve member (70) between an intermediate dome fluid chamber (52) and an exhaust chamber (54) communicating with exhaust port (52) and exhaust line (38). Spindle valve member (70) has an annular sealing member or membrane (104) having a relatively thin body (105) with opposed beads (106, 108) along inner and outer peripheries of body (105) for sealing between spindle valve member (70) and the adjacent retainer sleeve (94). Any positive backpressure forces from exhaust line (38) are balanced against spindle valve member (70) by annular seal (80) and membrane (104).

Abstract: An actuator utilizing the pressure of a gas is used to operate a diaphragm-operated control valve. An operating force generated by the actuator is varied by feeding and discharging a gas such as N2 through a narrow metallic tube. This is conducted by remote control, by means of electromagnetic valves provided in an environment at room temperature. The state of the control valve is monitored by a flow rate sensor which detects an actual flow rate of a fluid being controlled. Based on a signal representative of the detected actual flow rate, the electromagnetic valves for the actuator are controlled so that the fluid always flows at a desired flow rate. The gas such as N2 is heated by a heat exchanger in a high-temperature atmosphere in the vicinity of the actuator, to thereby prevent cooling of the fluid being controlled.

Abstract: A modulating relief valve comprising a main relief valve and a dome pressure control system. The main relief valve has an inlet subject to system pressure, an outlet, a valve member normally sealing the inlet, a piston that rises and falls wit the valve member, and a dome adjacent to the piston, the dome having a dome pressure. The dome pressure control system is attached to the main relief valve.

Abstract: A method and apparatus for evacuation of liquids, such as wastewater from e.g. wash basins, urinals, bath tubs or showers, whereby the liquid is collected in a sump, generates a hydrostatic pressure and is evacuated from the sump through a vacuum pipeline after a predetermined hydrostatic pressure is generated. In order to avoid flexible control conduits and to achieve time controlled evacuation with a simple mechanism, valves are integrated in a housing and operated by pressure differences acting on diaphragms after a certain hydrostatic pressure has been generated. One of the valves opens a connection between the sump and the vacuum pipeline to evacuate the liquid.

Abstract: A water system uses a pressure reservoir of extremely small size. A valve device is placed between a water pump and the pressure reservoir. The valve device has a constant outlet pressure function to limit the flow from the pump at high pressures. The pump is turned on and off responsive to a pressure on/off switch located down stream of the valve device. The valve device maintains the pressure to the reservoir below the off switch pressure except for a dribble flow. The dribble flow fills the reservoir when there is little or no water usage from the reservoir. The dribble flow is achieved by a notch or groove in the valve surfaces of the valve device. Each time the valve opens any debris in the notch or groove is washed from the notch or groove thereby keeping the notch or groove free of debris.

Abstract: The present invention relates to a safety valve for a containment (16) comprising a tubular body composed of a main branch (11) and a secondary branch (12) connected to said main branch (11) and opening into it via an aperture in the side of said main branch, a piston (13) mounted so that it slides inside said main branch (11) to free the said lateral aperture from the main branch, an upper stop (14) and a lower stop (15) both mounted inside the main branch and limiting the upward and downward displacement of said piston (13), the lower section of said main branch (11) being subject to a reference pressure, wherein an additional safety apparatus (25) is positioned under the tubular body between the lower section of said main branch and said reference pressure such that the maximum safety throughput rate of which the valve is capable is released in the event of an incident.

Abstract: Normally closed valves that operate in the environment of nuclear power plants are provided with surface-modified valve seat components to alleviate sticking of the valves. The surface modification is achieved by ion implantation of a coating of, for example, platinum, palladium, platinum/palladium or palladium/gold on at least one valve seat component.

Abstract: A spring diaphragm for use in automatic hydraulic control valves of the type having a valve body having an inlet chamber, and an outlet chamber and a spring diaphragm interposed between the inlet and outlet chambers, which spring diaphragm, as a result of hydraulic pressure, is automatically moveable between an open and closed position, in which the diaphragm allows and prevents, respectively, communication between the inlet and outlet chambers, includes a two-part diaphragm element including a first lower part and second upper part generally spaced apart from one another, the first lower part being in the form of a flexible elastic disc which performs the function of a hermetic seal between the inlet and outlet chambers when the spring diaphragm is in the closed position and the second upper part being connected to the first part and being in the form of a resilient disc which performs the function of a spring to normally bias the spring diaphragm from the open to the closed position.

Abstract: An integrated pneumatic pressure regulator assembly including a housing having an inlet adapted for fluid communication with a supply of pneumatic pressure, an outlet adapted for fluid communication with at least one pneumatically actuated device and an exhaust port. A pilot regulator valve is in fluid communication with the inlet and is operable to provide a pilot pressure. A pilot operated regulator valve is also provided in fluid communication with the inlet and the outlet. The pilot operated regulator valve is responsive to the pilot pressure to regulate the supply pressure from the inlet to a predetermined system pressure delivered through the outlet to a pneumatically actuated device during normal operation.

Abstract: A gas blanket controller, comprising a housing defining a chamber sealed with a diaphragm on a first side of the chamber, and a fitting for a tank outlet on another side of the chamber; a rod secured to the diaphragm for movement with the diaphragm; a rod guide secured to the housing, the rod being guided by the rod guide; weights secured to the rod providing a force resisting movement of the rod; a control linkage secured to the rod; a microswitch mounted on the housing, the microswitch having a toggle that is actuated by the control linkage; a gas blanket supply line; a gas blanket motor control valve on the gas blanket supply line; a communication link between the microswitch and the gas blanket motor control valve; and the rod having a range of motion such that the toggle is operable by contact with the control linkage, whereby the microswitch opens and closes the gas blanket control valve upon operation of the toggle.

Abstract: In a vacuum pressure control system constituted of a vacuum vessel, a vacuum pump sucking gas in the vacuum vessel, a vacuum proportional opening and closing valve disposed on a pipe connecting the vacuum vessel and the vacuum pump, the vacuum proportional opening and closing valve changing its opening to change the vacuum pressure in the vacuum vessel, a pressure sensor to measure the vacuum pressure in the vacuum vessel and a vacuum pressure control device to control the opening of the vacuum proportional opening and closing valve based on the output of the pressure sensor, the vacuum proportional opening and closing valve is provided with a valve seat, a valve member with a tapered surface in its outer periphery and a pilot valve, the valve member being movable along a center line of the valve seat to change a clearance area between the valve seat and the tapered surface, and the vacuum pressure control device controls a servo valve to change the pressure of air to be supplied to the pilot valve based on t

Abstract: A portable system of inter-connected smaller and larger canisters for near simultaneous vacuum and liquid transfer free from any external power. Captured vacuum in the canisters is employed for waste liquid extraction and a subsequent pressure transfer may take place without any liquid being exposed to the atmosphere. A mechanical manifold is adapted to receive the canisters, and one or more canisters may be physically connected to the manifold and are left in place as a user drives to another site location. An intermediate canister in the system is fitted with either manual or a self tending valve for the vacuum and pressure modes of the system.

Abstract: A linear mechanical line break detector for use on a mobile transport, the mobile transport having a supplying vessel disposed thereon for transporting a fluid product, the vessel having an outlet for transferring fluid product from the supplying vessel, the flow of fluid product from the outlet being controlled by a fluid product shut off valve, the outlet being coupled to a transfer line during transfer of fluid product under pressure from the supplying vessel to a receiving vessel, the transfer line being coupled to the receiving vessel for effecting transfer of the fluid product to the receiving vessel, includes a sensor/actuator that is in fluid communication with the transfer line for sensing the pressure of the fluid product therein.

Abstract: A pneumatic regulating valve that operates on high-temperature, high-pressure gases. This invention reduces the upstream pressure of a flow of gas, which can be as high as 10,000 psia, down to a level usable by downstream control valves, which may require controlled pressure input. The springs and seals of this invention are isolated from the high temperature and pressure of the upstream gas, thus enabling regulation of gas flows of up to 10,000 psia and 2,500.degree. F.

Abstract: A valve unit comprises a single electromagnetic actuator for controlling both an ON-OFF valve for cutting off the gas and a modulation valve; the latter is subject to independent resilient loads for regulating the minimum pressure delivered and for regulating the pressure up to the maximum pressure at the modulation stage.

Abstract: A safety relief valve (10) has a diaphragm actuator (24) including a diaphragm (26) with a dome chamber (34) on one side of the diaphragm (26) and an underdome chamber (36) on an opposed side of the diaphragm (26). A diaphragm operated pilot control valve (38) has a valve body (46) with a pilot sensing port (54), a pilot dome port (64), and a pilot underdome port (60) in fluid communication with a pilot valve chamber (52). A slidable pilot valve member (68) connected to diaphragm (42) is mounted for movement between two pairs of opposed annular seats (80, 84 and 82, 86). Actuation of pilot valve member (68) at a low set pressure permits fluid communication of inlet fluid from pressure vessel (15) to underdome chamber (36) and exhaust of fluid from dome chamber (34) to boost opening of main relief valve member (22).

Abstract: The invention provides a pilot valve apparatus for use in an automatic fluid control system for maintaining pressure downstream from a main control valve between two setpoints irrespective of flow changes through the main control valve. The pilot valve has a flexible pilot diaphragm which moves with a moveable pilot valve member to cooperate with a fixed pilot valve member to control fluid flow through the pilot valve apparatus. The pilot valve controls control pressure acting on the main control valve. An actuator apparatus connected to a body of the pilot valve apparatus has a moveable actuator partition which is exposed to a pressure differential signal reflecting flow through the main control valve. A resilient connector cooperates with the actuator partition and the pilot diaphragm to permit limited relative movement therebetween, and to transfer resilient force to the pilot diaphragm resulting from movement of the actuator partition.

Abstract: A fluid flow control valve and actuator therefor for changing fluid flow rate. A fluid flow control valve comprises a housing having a bore and an inlet and an outlet which form a flow passage through the housing. The valve also comprises a piston mounted in the bore, a fluid flow orifice communicating with the inlet and the outlet, springs which bias the piston toward the inlet, and a valve seat which is matable with the piston and is slidable within the housing to vary fluid flow rate. An actuator for changing fluid flow rate of the valve is comprised of a housing having a bore, a piston dividing the bore into a first chamber and a second chamber, springs in the second chamber for biasing the piston toward the first chamber, an actuator fluid inlet communicating with the first chamber, and an actuator fluid outlet communicating with the first chamber.

Abstract: A control system for the operation of the subsurface safety valve is disclosed. The control system uses a pressurized gas chamber, as well as a shuttle valve which connects to the main fluid pressure supply from the surface. The shuttle valve is connected to the gaseous chamber as well as to a barrier piston. As a result of the arrangement, leakages between the downstream side of the operating piston and the shuttle valve result in a reestablishment of the pressure balance on the operating system which allows the subsurface safety valve to close. Additionally, in the event of loss of gaseous pressure, the same pressure-balancing effect occurs on the operating piston, which allows the subsurface safety valve to go to a closed position. The configuration of the control system, which includes a gaseous chamber, allows for disconnection of the hydraulic fluid supply before the predetermined depth is reached to facilitate the connection of a tubing hanger.

Abstract: A water purifier generally associated with a beverage dispenser is disclosed. The water purifier includes a first conduit having a first end and a second end opposite to the first end, a second conduit having a first end and a second end opposite to the first end, a cistern disposed between the first and second conduits, and a water purifying device disposed in the flow path of either the first conduit or the second conduit. The first end of the first conduit is arranged to conduct water to be purified into the first conduit, and the second end of the second conduit is arranged to conduct the purified water from the second conduit to a location outside of the water purifier. The flow of the water from the second conduit to the first conduit is completely prevented and interrupted whenever the water attempts to flow from the second end of the second conduit to the first end of the first conduit through the arrangement of the second end of the first conduit and the cistern.

Abstract: A vehicle fluid pressure supply system in which a fluid pressure supply pump (10) is connected via solenoid-operated flow control valve (15) with a plurality of separate fluid pressure operated circuits(A, B, C) each operating separate functions of the vehicle. Detectors (25, 26, 27, 30 to 35) are provided for detecting the current operative state and the fluid pressure supply status of each circuit, and an electrical control unit (28) means which receives signals from the detectors operates the control valve to direct available pump flow to the appropriate circuit to maintain each circuit at least at a minimum pressure level required to operate the associated function.

Abstract: A manifold assembly 10 for operating a safety relief valve 12 includes a manifold block 60 having a block inlet port 230, a block dome pressure port 232, and a pair of control cavities 220 and 222 each adapted for receiving a pilot valve 70 or auxiliary control member 80. Inlet control valves 74, 84, dome pressure control valves 76, 86, and test control valves 78, 88 are each mounted on the manifold block. One of the pilot valves may be maintained on-line for controlling operation of the safety relief valve, while the other pilot valve may be isolated for service. A cartridge pilot valve assembly 70 includes a bushing 126 for facilitating installation and removal of the cartridge valve assembly from the valve block. An improved metal washer 122 is provided having inner and outer knife edges 330, 334 for sealing engagement between the valve body 110 and the block 60.

Abstract: In a control valve abnormality detection method of detecting abnormality in a control valve, a characteristic expression representing the relationship between three factors in the normal state of the control valve is pre-set. The three factors consist of the displacement of the valve stem, a driving force from the valve stem driving device which changes upon displacement of the valve stem, and the force of the fluid which acts on one end of the valve stem through the valve. The three factors are detected on the basis of measurement result. On the basis of two factors selected from the detected three factors, the estimated value of one factor, which is not selected, is calculated by using the pre-set characteristic expression. The detected value of one factor, which is not selected, is compared with the calculated estimated value, and abnormality in the control valve is determined on the basis of the comparison result. A control valve abnormality detection apparatus is also disclosed.

Abstract: Each gas expansion station of a distribution network fed with gas in accordance with the invention comprises at least one regulator-expander provided with a valve member disposed on a main duct, a pilot valve, a safety valve provided with a valve member disposed in the main duct, and a differential member co-operating with the pilot valve and the safety valve which is disposed upstream from the regulator-expander to close the safety valve automatically under the control of the pilot valve in the event of the downstream pressure in the main duct downstream from the expansion station concerned exceeding a predetermined threshold value, and to operate automatically, after the downstream pressure has been restored to below the predetermined threshold value, either to reopen the safety valve if the regulator-expander of the expansion station concerned is not itself giving rise to a leak at its valve member, or else to keep the safety valve closed if the regulator-expander is not itself providing gastight sealing a

Abstract: The present invention relates to an automatic constant-pressure lift valve provided with a pilot valve unit having an A valve unit and a B valve unit, and an external control force applying means that can be simply adjusted to set a predetermined valve-outlet pressure.A main valve unit is constructed so that an abnormal rise in the valve-outlet pressure can be avoided at start and stop and continuous operation of a pumping or conveying pump facility. The automatic constant-pressure lift valve has a construction capable of easily maintaining watertightness when the line is shut off.The pilot valve unit is not provided with any fixed flow restriction regulating passage, such as a needle valve. When the main valve unit, and the A valve unit and the B valve unit of the pilot valve unit are clogged, those valves open automatically for automatic cleaning.This constant-pressure lift valve has an excellent industrial effect.

Abstract: An assembly and method for controlling the opening of a safety relief valve exposed to a system fluid pressure and containing a control fluid which controls the opening of the safety relief valve. The assembly includes a pilot valve connected to the safety relief valve and adapted to respond to a predetermined pressure of the system fluid for permitting flow of the control fluid. A regulator receives the control fluid and operates to reduce the pressure of the control fluid a predetermined amount. The safety relief valve opens in response to the reduction of the control fluid pressure, and the remaining control fluid pressure modulates the opening of the safety relief valve.

Abstract: A sensor and valving system for controlling the flow of liquid coolant in a welding electrode cooling circuit using coolant under pressure in supply and return lines. The system is responsive to loss of coolant to the welding electrodes by pressure response upon loss of coolant detection, the coolant supply is cut off and effective lines are isolated allowing for repair or replaceable without additional loss of coolant from the system.

Abstract: The invention relates to a relief valve and intends to provide a relief valve designed to improve response and operational stability. In an overload prevention safety device in which a main valve element including a pilot valve element in a valve case is arranged, a pilot valve is opened by oil pressure exerted on the pilot valve element from an oil passage formed in the main valve element while resisting to an energizing means for energizing the pilot valve element. By this operation oil pressure is exerted on the pilot valve element side of the main valve element to open the main valve. An oil passage is designed to be constructed in holes with different diameters with a small-diameter section, a taper section, and a large-diameter section continuously arranged in that order. A pilot valve seat is sealably in contact with the pilot valve element mounted at the connections between the small-diameter section and the taper section.

Abstract: A rate-of-flow control valve assembly actuable as a function of velocity of fluid in a conduit includes a sensing plate projecting into the conduit, substantially perpendicular to a direction of flow in the conduit and a sleeve valve located downstream of the sensing plate. The sleeve valve includes a substantially cylindrical, flexible rubber sleeve surrounded by a control chamber, and an outer rigid sleeve, the flexible sleeve adapted to vary the flow rate of the fluid through the sleeve valve. Also included is a spool valve controller operatively connected to the sensing plate and in communication with the control chamber in the sleeve valve, the spool valve operable to control the flow of fluid into and out of the control chamber as a function of movement of the sensing plate in the conduit.

Abstract: A control system is provided for monitoring and regulating fluid pressure at a remote and/or potentially hazardous location along the length of a fluid flow conduit, without requiring a pressure sensor device at the remote site. The control system comprises a controller responsive to fluid pressure and flow rate readings taken at a convenient and/or safe location along the length of the flow conduit, to derive fluid pressure at the remote site. The controller provides a display of the derived pressure and/or operates a control valve at the safe site to regulate the pressure at the remote site.

Abstract: An electropneumatic converter controlled by solenoid valves, in which the solenoid valves are connected respectively to the feed pressure and to atmosphere, each via a pressure regulator controlled by a differential pressure measurement device connected across a respective solenoid valve, so as to maintain a constant pressure difference across the solenoid valves.

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: An exhaust reduction system for reducing gas emissions in pipeline controlling devices which operate control valves, which system adjusts and reduces the pressure of a control stream of gas from a conventional line pressure regulator to the control valves. In a preferred embodiment the exhaust reduction system operates in cooperation with the conventional line pressure regulator which reduces the pressure of the gas from the pipeline to a selected system pressure and includes a system high pressure regulator, a system low pressure regulator and in some cases, a selector relay, for further reducing the pressure of the incoming gas and channeling the gas at reduced pressure to at least one controller.

Abstract: A dual signal head sensor, which is a fluid pressure differential sensitive control valve, has a diaphragm responsive to changes in fluid pressure on opposite sides thereof and a ported sleeve having a spool valve axially movable in response to diaphragm motion. The head sensor monitors a fluid pressure differential and provides fluidic control signals in response to sensed variations in the pressure differential. A pair of chambers separated by the diaphragm receive variously pressurized fluids and thereby impress across the diaphragm the pressure differential being monitored. The head sensor has a ported sleeve with a high pressure inlet, a low pressure return, two control connections or dual signal outputs, and a movable spool having 4 lands.

Abstract: The device for the inert rendering of a storage container 21, using a cylinder of pressurized inert gas, which has a pressurizing pipe 3 and an inert-rendering pipe 6 which are intended to be connected to the storage container, and an inert-gas intake pipe 4 intended to be connected to the cylinder of inert gas.It comprises a pilot valve 1 and a supply valve 2 controlled by the pilot valve. The control inlet of the said pilot valve 1 is connected to the pressurizing pipe 3; the inlet and the outlet of the supply valve 2 are respectively connected to the inert-gas intake pipe 4 and to the inert-rendering pipe 6.

Abstract: A valve assembly is provided to control a flow of liquid through a drain conduit from a sink in an aircraft. When the aircraft is in an inactive condition on the ground, a fluid motor presses a main valve member lightly against a main valve seat. At this time, liquid in the drain conduit can leak past the main valve member. However, at this time, the main valve member is effective to block a reverse flow of odors through the drain line into the cabin of the aircraft. When the aircraft is operating in the air above the ground, the motor presses the main valve member against the main valve seat with sufficient force to seal the drain conduit and prevent the leakage of fluid past the main valve seat. When a predetermined amount of liquid has accumulated in the drain conduit upstream from the main valve seat, a motor control assembly effects operation of the motor to move the main valve member away from the main valve seat to allow the liquid to flow through the drain conduit past the main valve seat.

Abstract: A fluid pressure variation valve for use in pressurized fluid systems situated in a pressurized fluid line, for the purpose of reducing the pressure in the fluid line when fluid is not in use, while allowing the normal high fluid pressure of the pressurized fluid system to be maintained when fluid is in use. The valve unit comprises a hollow housing where a valve is moveably situated. A diaphragm is attached to the valve. Two relief valves are disposed in the hollow housing. A first relief valve provides selective communication between the inlet and outlet of the valve housing. In the closed position, the valve defines a first chamber at the inlet of the valve body. A second chamber is defined between the outlet of the valve housing and the second relief valve. A third chamber is defined between the diaphragm and a passage connecting the second relief valve. The third chamber allows selective communication with the outlet via the second relief valve.