Abstract: A downhole valve comprises a tubular body and a valve member. The valve member is normally closed and in the closed position may prevent or restrict passage of a working fluid through the body. The valve member is movable to an open position, a first working fluid pressure differential being necessary to move the valve member from the closed position and a lower second working fluid pressure differential being necessary to maintain the valve member in the open position.

Abstract: The fluidic system with an unclogging feature of the preferred embodiment includes a flow channel, a sheath pump to pump sheath fluid from a sheath container into an interrogation zone, and a waste pump to pump waste fluid from the interrogation zone into a waste container. The sheath pump and/or the waste pump draw sample fluid from a sample container into the interrogation zone. The fluidic system also includes a controller to adjust the flow rate of the sample fluid from the sample container into the interrogation zone. The pump and controller cooperate to propagate a pulsation through the flow channel from the pump if the flow channel is clogged. The fluidic system is preferably incorporated into a flow cytometer with a flow cell that includes the interrogation zone.

Abstract: The invention relates to a relief valve comprising a first valve body (3) for opening and closing a fluid passageway (33) between a first valve connection (31) and a second valve connection (32), a second valve body (4) which is disposed on the first valve body (3) and is used for opening and closing a valve passageway (3A) located between the first valve connection (31) and a valve interior (9) in the first valve body (3), at least one throttle duct (11) that establishes a connection between the valve interior (9) and a face (3B) of the first valve body (3), a spring (10) for moving the second valve body (4) in an opening direction of the second valve body (4), and an actuator (2, 7) for moving the second valve body (4) in a closing direction.

Abstract: A gas flow regulating device including a housing assembly, an inlet tube assembly, and a biasing device. The housing assembly has a main housing, a valve seat body, and a distal plate forming an outlet orifice. The inlet tube assembly includes a proximal inlet end, a tube forming a lumen, and a flange, and is slidably disposed within the main housing, biased to an open state by the biasing device. The flange separates middle and constant pressure chambers within the housing assembly. The inlet tube assembly is transitionable to a closed state in response to pressure in the constant pressure chamber to generate a relatively constant flow rate of air exiting the device via the outlet orifice.

Abstract: An outflow valve for an aircraft has a frame for arrangement in an opening of an outer shell of the aircraft, a first flap pivotably arranged in the frame for controlling a flow cross-section of at least one first inflow opening and at least one outflow opening. To achieve a simplified construction of the ventilation system of the aircraft, the outflow valve has a second inflow opening configured to be closable by means of a drivable adjustable member.

Abstract: The present invention relates to a method and apparatus for generating pressure suitable in magnitude for powering micro-sized devices. The present invention typically comprises a gas generation chamber that is equipped with an activation element and filled with a gas-containing liquid. Powering of the activation element causes gas within the liquid to be released. Upon release a series of pressure distribution channels deliver the gas to a wide variety of peripheral microfluidic devices. A series of one-way valves and multi-chambered configurations allow for a wide variety of pressures to be generated from a single pressure generation device. By manipulating the scale of the pressure generation device, lab-on-chip, hand held, and bench top applications are possible and may readily be interfaced to allow a substantial amount of user control of the system.

Abstract: A shear valve employing a two-stage main poppet valve. The two-stage main poppet valve that can be opened with less force than normally required by prior art designs. For example, if there is pump pressure trapped on the upstream side of the two-stage main poppet valve and little or no pressure or atmospheric pressure on the downstream side, more force than can be provided may be required to open the two-stage main poppet valve to reset the shear valve after the two-stage main poppet valve is closed. The two-stage main poppet valve is designed to first begin to equalize pressure differential across the shear valve without opening a main poppet valve head from its seat inside the shear valve. Thereafter, the main poppet valve head can be opened with less force than otherwise would be required.

Abstract: A valve includes a body, a throttling ball, and a shoe. The body includes an upstream flow passage and a downstream flow passage in fluid communication with an interior cavity of the body. The throttling ball is rotatable within the interior cavity on an axis to adjust the valve from a closed position to an open position and includes a fluid conduit extending through the throttling ball, where the fluid conduit is alignable with the upstream flow passage and the downstream flow passage. The shoe is disposed in the cavity abutting an interior surface of the cavity and includes a fluid passage there through having an inlet being alignable with the flow conduit of the throttling ball and an outlet being alignable with the downstream flow passage of the body. The interior surface of the shoe is disposed adjacent to and tracking an external surface of the throttling ball.

Abstract: One embodiment of the present invention can include a flow control device a flow control device that comprises an inlet, an outlet in fluid communication with the inlet, a pressure sensor, which may or may not be the only pressure sensor of the fluid control device, and a controller coupled to the pressure sensor. The controller can be configured to generate a valve control signal based on a measured pressure at a single pressure sensor.

Abstract: A method includes associating a plurality of valve balancing units with a plurality of valves in a hydronic network. The method also includes adjusting a setting of at least one of the valves using at least one of the valve balancing units to balance the hydronic network. Adjusting the setting could include identifying a differential pressure across a valve and a flow rate of material through that valve. Adjusting the setting could also include comparing the identified differential pressure to a target differential pressure and/or the identified flow rate to a target flow rate. Adjusting the setting could further include instructing an actuator to adjust the setting until the identified differential pressure is within a first threshold of the target differential pressure and/or the identified flow rate is within a second threshold of the target flow rate.

Abstract: A pressure type flow control device enabling a reduction in size and an installation cost by accurately controlling the flow of a fluid in a wide flow range. Specifically, the flow of the fluid flowing in an orifice (8) is calculated as Qc=KP1 (K is a proportionality factor) or Qc=KP2m(P1?P2)n (K is a proportionality factor and m and n are constants) by using a pressure P1 on the upstream side of the orifice and a pressure P2 on the downstream side of the orifice. A fluid passage between the downstream side of the control valve of the flow control device and a fluid feed pipe is formed of at least two or more fluid passages positioned parallel with each other. Orifices with different fluid flow characteristics are interposed in the fluid passages positioned parallel with each other. For the control of the fluid in a small flow area, the fluid in the small flow area is allowed to flow to one orifice.

Abstract: A gas flow rate verification unit capable of enhancing reliability of gas flow rate verification. The gas flow rate verification unit has a first cutoff valve that is connected to a flow rate control device and to which gas is inputted, a second cutoff valve for discharging the gas, a communication member for allowing the first cutoff valve and the second cutoff valve to communicate with each other, a pressure sensor for detecting the pressure of the gas supplied between the first cutoff valve and the second cutoff valve, a temperature detector for detecting the temperature of the gas supplied between the first cutoff valve and the second cutoff valve, and a control means for verifying the flow of the gas flowing in the flow control device, the verification being performed by using both the result of the pressure detected by the pressure sensor and the result of the temperatures detected by the temperature detector.

Abstract: A valve arrangement for a vacuum pump assembly selectively opens and closes communication between a vacuum pump, evacuation vessel, and a volume to be evacuated. The valve arrangement allows the evacuation vessel and any conduit connecting the vacuum pump and evacuation vessel to the volume to first be evacuated without providing a vacuum to the volume. The valve arrangement also allows the volume to be connected to the evacuation vessel but cut-off from the vacuum pump so that at initial stages of the evacuation process for the volume dead air contained within the volume may be communicated to the evacuation vessel rather than drawn out by the vacuum pump. Once the dead air, or portions thereof, has been removed from the volume, the valve arrangement may cut-off communication with the evacuation vessel, establish communication between the vacuum pump and the volume, and allow the vacuum pump to provide negative air pressure to the volume so that the volume may be evacuated.

Abstract: A gas regulator includes a housing and a pressure regulator positioned within the housing along a first axis for controlling the pressure of gas received from a pressurized source. A flow meter controls the flow rate of the gas received from the pressure regulator. The flow meter is positioned relative to the housing along a second axis, transverse to the first axis. An outlet nozzle member has a nozzle stem and is positioned along the first axis. The outlet nozzle member receives the gas from the flow meter and delivers the gas through the nozzle stem.

Abstract: The present invention provides an advanced spray control system for controlling a sprayer, which comprises a controller, a plurality of sensors and feedback means, and an output means for controlling the application system of the sprayer. The controller receives inputs from the operator through a user interface, and/or various feedback signals from the sensors of the system (e.g., a flow meter, or a pressure transducer). After processing these inputs, the controller sends signals to other components of the sprayer, such as, the pump, the storage means, the boom sections, and/or the nozzles, to maintain or change their operating conditions. Also provided are a method of controlling a sprayer using the spray control system and a sprayer comprising the spray control system of the present invention.

Abstract: A gas supply system 20 for supplying a gas into a pumping system 10 is provided, the pumping system including a plurality of pumping means 14, 16, the gas supply system comprising a gas inlet 22 and plurality of gas conduits 24, 25 fluidly connected to the gas inlet and each having a gas outlet 27, 28 fluidly connectable to the pumping system 10, wherein the gas outlets of the plurality of gas conduits are in parallel fluidly connectable to the pumping system and each gas conduit is provided with a gradient adjustment means adapted to provide at least one gradient of gas amount supplied to the pumping system.

Abstract: The invention relates to a valve (16), in which a fluid inlet opening provided in a valve housing (1) is connected to a fluid outlet opening (3) downstream of the fluid inlet opening by a fluid passage (2) and with a valve closing body (6) which may be moved between a first position which opens the fluid outlet opening (3) and a second position closing the fluid outlet opening (3) by means of an actuator, said body being housed in the valve housing (1). According to the invention, pressure waves are avoided by at least one fluid drain channel (5) branching off the fluid passage (2) via at least one fluid drain opening (4) in the vicinity of the fluid outlet opening (3) and a device is provided in the valve housing for the alternate opening of the fluid drain opening (3) and the fluid outlet opening (4) such that fluid may continuously flow through the fluid passage (2).

Abstract: A diaphragm-type control valve having a diaphragm and a valve body is provided preferably for use in the separation of and fluid control between a fluid source and a pressurized gas volume. The diaphragm element and a port in the body together form an intermediate chamber that eliminates the need for a check-valve downstream of the valve. In one preferred embodiment, an inner surface of the valve body defines a chamber having an inlet and an outlet in communication with the chamber, and an elongated seat member defining a groove in communication with the port. A diaphragm member having upper and lower surfaces is disposed within the chamber. The lower surface preferably includes a pair of spaced apart elongated members defining a channel therebetween. The diaphragm member engages the seat member placing the channel in communication with the groove to define an air seat in communication with the port.

Abstract: A subsea system comprises a wellbore within a reservoir, equipment downstream of the wellbore, and a barrier connected to the equipment. The equipment is rated for a maximum pressure that is less than a maximum reservoir pressure and equal to or greater than the maximum reservoir pressure less external hydrostatic pressure experienced by the equipment. The barrier is rated for a maximum pressure that is equal to or greater than the maximum reservoir pressure.

Abstract: Aspects include a valve comprising a flowing liquid, operable to control a flow of gas through a port. Certain aspects include reaction chambers operable to react gases, and in some aspects gases are substantially contained within an envelope comprised of a flowing liquid. Certain embodiments control gas entrance into a chamber with a valve comprised of a flowing liquid controlling gas flow through a port. Various gas scrubbing systems are described, including systems comprising reaction chambers operable to react gases that yield substantial amounts of solid reaction products. Methods for controlling gas flow are disclosed. Systems and methods include sequential steps of wet-scrubbing, reacting and further wet-scrubbing a gas stream.

Abstract: A backflow and flow rate control system, comprising: a flow restrictor; a flow regulator chamber located down-stream of the flow restrictor; a control chamber configured to receive a portion of the fluid from a location upstream of the flow restrictor; a moveable element with no sliding parts positioned between the control chamber and the flow regulator chamber, wherein the moveable element is configured to move in response to a difference in pressure between the flow regulator chamber and the control chamber; a flow rate regulator configured to control the flow rate of the fluid in response to the movement of the moveable element; and a non-return regulator coupled with the moveable element and configured to control back-flow of the fluid.

Abstract: The present invention provides a method for mixing three or more fluids inside a capillary. The present invention further provides a method for optimizing efficient mixing of two or more fluids inside a capillary, and a computer-readable medium for use by a processor to carry out this method. Additionally, the present invention provides an automated system for mixing two or more fluids inside a capillary. Also provided is a system for optimizing efficient mixing of two or more fluids inside a capillary.

Abstract: In some embodiments, apparatus for allowing one-way flow of fluid into or out of a tubular member includes a base pipe having at least one port formed therein. At least one valve is engaged with the base pipe, associated with at least one port and capable, at least temporarily, of allowing fluid flow in one direction and disallowing fluid flow in the opposite direction through the associated port(s).

Abstract: The present application is directed to an apparatus and method of managing transport of fluid commodities in a pipeline network. The method includes obtaining operational settings, which include equipment settings and measured parameters, associated with a pipeline network as a fluid commodity is transported through the pipeline network. From the operational settings, a recommendation is generated concurrently with the transport of the fluid commodity through the pipeline network to optimize at least one of the operational settings. The recommendation comprises revised equipment settings associated with equipment disposed along the pipeline network. The equipment settings in the recommendation may be based on empirical data from previous experience with the transport of fluid commodities through the pipeline network and/or based on theoretical data from modeling of the transport of the fluid commodity through the pipeline network.

Abstract: Method for controlling a compressed air unit which consists of several compressed air networks (2 and 3) having at least one commonly controllable component, characterised in that, on the basis of measurement data of at least one of the above-mentioned compressed air networks (2 and 3), at least the above-mentioned common component (11) is controlled by at least one controller (20).

Abstract: A method for operating a multi-track rotary valve having plural tracks for the separate introduction to vessels of at least 3 feed streams and the separate recovery from the vessels of at least 3 product streams and for simultaneous change of the flow paths of the streams. At least one stream is selected and maintained at lower pressure than the other streams so that any leakage flows from the other streams to the at least one selected stream.

Abstract: A method of storing and dispensing a fluid includes providing a vessel configured for selective dispensing of the fluid therefrom. The vessel contains an ionic liquid therein. The fluid is contacted with the ionic liquid for take-up of the fluid by the ionic liquid. There is substantially no chemical change in the ionic liquid and the fluid. The fluid is released from the ionic liquid and dispensed from the vessel.

Abstract: A system and method for controlling a flow of a fluid using a multi-mode control algorithm is described. One embodiment includes a method for changing the multi-mode control algorithm from a closed-loop mode to an open-loop mode. The method includes receiving at least one sensor indicator generated by a sensor. The multi-mode control algorithm is modified from the closed-loop mode to the open-loop mode when, based on the at least one sensor indicator, the threshold condition is satisfied. The multi-mode control algorithm is used by a flow controller to control a flow of a fluid according to a set point.

Abstract: A rocker type diaphragm valve is disclosed. The diaphragm (428) in the diaphragm valve is asymmetric and the stroke of the diaphragm is offset from the center of the diaphragm. The two sealing surfaces (318, 320) that the diaphragm acts against form two planes that make an angle with respect to ones another. The diaphragm (428) may be fabricated in only one piece. The diaphragm (428) may also be made from a resilient material and shaped in such a way as to create a spring force holding the diaphragm into a default position in the valve.

Abstract: A backflow prevention device is to be installed between various equipment drain lines and a drain cover or drain pipe. The backflow prevention device provides an air gap operable to prevent backflow of sewer waste into the drain lines. The device includes a drainage hub and a tubing mount attached to the drainage hub. The drainage hub defines a liquid flow conduit throw which liquid discharged from the drain lines can flow and can be connected to the drain. The tubing mount supports the drain lines in such a way that the drain line effluent is positioned to be in fluid connectivity with the upper opening of the liquid flow conduit at a vertically displaced position from the drainage hub.

Abstract: An apparatus for evaluating scientific phenomena by feeding liquid to a minute channel, which is inexpensive, imposes little environmental load and enables advanced technology to be easily enjoyed and can eliminate experimental failures due to the clogging of the minute channel with a bubble, is provided. Before starting the experiment with the experimental liquid, the preparatory step of removing air in the minute channel by vigorously injecting inert dummy liquid which does not react with the experimental liquid into the minute channel and thereby filling the minute channel with the dummy liquid is carried out. If one round of preparatory step proves insufficient to wholly remove the air in the minute channel and a bubble is found in the dummy liquid, the step will be repeated until no bubble is found any longer in the dummy liquid.

Abstract: A system and method for start flow approach control for a proportional valve in a plasma cutter is provided that includes a controller configured to determine a target gas pressure set point for a plasma cutting operation and determine a ramp pressure set point offset from the target gas pressure set point. The controller is also configured to apply a full-open drive signal to an air pressure-closing proportional valve and monitor a pressure of gas flow output from the air pressure-closing proportional valve via a sensing device. The controller is further configured to apply a ramping drive signal to the air pressure-closing proportional valve after the pressure of the gas flow has reached the ramp pressure set point and apply a target-pressure drive signal to the air pressure-closing proportional valve after the pressure of the gas flow has reached the target gas pressure set point.

Abstract: The invention relates to an electro-hydraulic leak compensating device for a mobile crane lowering brake system in an open hydraulic circuit with a hydraulic motor (5) coupled with a lifting unit (6,7), a lowering brake valve (4) and a mechanical brake (9), with a pressure sensor (13) which measures the hydraulic pressure prevailing on the load side of the hydraulic motor (5) in the hydraulic circuit and on the side of the lifting conduit (3) before the mechanical brake (9) is closed, in particular immediately before it is closed, as well as a method of electro-hydraulically compensating for leaks of a mobile crane lowering brake system in an open hydraulic circuit with a hydraulic motor (5) coupled with a lifting unit (6,7), a lowering brake valve (4) and a mechanical brake (9), comprising the following method steps: measuring the hydraulic actual pressure prevailing on the load side of the hydraulic motor (5) before the mechanical brake (9) is closed, in particular immediately before it is closed; determ

Abstract: A turbine wheel and gear system rotate an output shaft in response to flow, where the output shaft is connected to a clutch cup that engages a clutch and valve disk. The disk cooperates with a valve seat formed on a piston to permit/prevent flow within the piston. During flow, the clutch clamps to the disk, and the piston and disk move downstream until an associated control member hits a stop, opening the valve (as the disk stops), while the piston continues downstream. The clutch rotates the disk and control member, and if a maximum flow volume occurs, the control member rotates to an interrupt position and is released from the stop, closing the valve. Passages allow restricted flow to disengage the clutch and permit a spring to move the piston and valve upstream until engaging a reset cam that rotates the control member back to an initial position.

Abstract: A constant flow valve mechanism for use in an inkjet printer includes a valve. A first port, a second port, and a third port are in fluid communication with each other through the valve. A portion of the valve is moveable and associated with the first, second, and third ports to produce a change in fluid impedance between the first port and the second port and the first port and the third port such that the fluid impedance between the first port and the second port changes at the same rate and in an opposite direction as that of the fluid impedance between the first port and the third port.

Abstract: Space vehicles such as space stations are often constructed as segmented inflatable structures which are susceptible to being punctured by small meteoric materials, resulting in small insidious leaks which are difficult to locate and repair. A method and apparatus are described in which a differential pressure transducer is positioned between segments of the space vehicle. Atmospheric gas pressure of all segments is continuously monitored. Analysis is performed on any pressure differentials which are determined to exist between adjacent segments. Detection of small leaks initiates an automatic isolation of the leaking segment. Detection of catastrophic leaks initiates an emergency evacuation of personnel from the affected segment.

Abstract: An apparatus for controlling a flow rate of fluid passing through a duct (10) includes a wedge (12) to produce a resistance against a flow of the fluid; pressure sensors (20-1, 20-2), to detect an inflow pressure and an outflow pressure at the upstream and the downstream of the duct (10), respectively, a flow rate controller (22) for measuring a flow rate corresponding to a differential pressure between the inflow and the outflow pressures, comparing the measured flow rate with a predetermined flow rate to regulate an opening angle at an outflow side of the duct (10) using a calculated opening angle, wherein the calculated opening angle being corresponded to a deviation of flow rate between the measured flow rate and the predetermined flow rate; and an error detector (28) for detecting an improper increase of the differential pressure to correctly adjust the opening angle regulated by the flow rate controller.

Abstract: The present invention is a nitrous oxide safety system or method that provides a safety control valve actuated by low-vacuum fluids to control the release of nitrous oxide therethrough. The nitrous oxide safety system may include a low-vacuum fluid, a nitrous oxide fluid, a scavenging mask assembly, and a safety control valve. The low-vacuum fluid is generated by a vacuum source operating to achieve a predetermined parameter and the nitrous oxide fluid is provided by a nitrous oxide source. The scavenging mask assembly is fluidly connected with the nitrous oxide source and the vacuum source. The safety control valve is fluidly connected to the fluid connection between the nitrous oxide source and the vacuum source. The safety control valve is configured to be actuated when the low-vacuum fluid is input to the valve to release a flow of the nitrous oxide fluid through the safety control valve.

Abstract: In one set of embodiments a selected section of tubular stock has its ends welded together to form a pillow-like pressure sensing device with an entry tube and an exit tube each configured to facilitate insertion of the pressure sensing device into the flow path of IV infusate in an IV administration set or system. Fluid pressure in excess of a predetermined amount reconfigures the pressure sensing device from a generally oval configuration to a generally circular configuration to restrict and/or cut off fluid flow into the device while permitting fluid flow from the device to reduce the fluid pressure again reconfiguring the device back to its generally oval configuration and permitting fluid flow into and through the device.

Abstract: A multizone gas distribution system configured to be coupled to a process chamber is described. The multizone gas distribution system comprises a first gas distribution element and a second gas distribution element. Additionally, the multizone gas distribution system comprises a flow control system configured to divide a flow of process gas between the first gas distribution element and the second gas distribution element. Further, a system controller coupled to the flow control system is configured to adjust the flow of process gas to the first gas distribution element and the second gas distribution element according to a target flow condition. Further yet, the system controller is configured to monitor the flow control system in order to perform at least one of monitoring a flow rate, adjusting a flow rate, controlling a flow rate, determining a fault condition, and determining an erroneous fault condition.

Abstract: A pressure relief valve for blown fibre closures is provided having constituent components fabricated from plastic. An adaptor is provided for connection to a blown fibre closure, and a body welded to this adaptor, is provided to enclose a piston and a spring within, such that they are protected from the ingress of silt and water. The piston is arranged to provide a double seal such that a pressure relief valve plug and an opening in the enclosing body are closed or opened simultaneously to prevent the ingress of silt and/or water on the one hand and the unhindered escape of pressurized fluid on the other.

Abstract: A method for automatically controlling a flow in a flow line system including a flow line, a flow line inlet and outlet, and a control valve located in the flow line at the outlet. The method includes controlling the opening of the valve with a control unit. An outlet flow rate is measured or estimated from the flow line. The valve is opened. It is determined if a sudden drop occurs in any of the measurements or estimates. It is decided if a liquid blockage in the flow line is present or approaching. If a liquid blockage is indicated as present or approaching, the opening of the valve is increased by an amount determined by the measurements or estimates. Any further manipulation of the valve is inhibited before a non-zero time period has expired. The steps are repeated. Also a system and a computer program product.

Abstract: A mass flow controller includes a pressure sensor that senses pressure within the mass flow controller and displays the pressure. The pressure display may be local, mounted directly to the mass flow controller, or it may be connected through a link to the mass flow controller for remote display.

Abstract: A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

Abstract: A variable pressure regulator control device comprising a valve body having a fluid inlet, a fluid outlet, a fluid pressure-sensing chamber, and a valve seat in fluid communication with said inlet and defining an opening into said chamber, a resilient member having an outer edge and a self-restoring wall of the chamber which is responsive to pressure in said chamber, a valve stem extending through said chamber towards the valve seat, a valve element cooperating with said valve seat, said valve element being located between the valve seat and said fluid inlet, an adjuster mounted to said valve body in a position to deflect said resilient member, thereby moving the valve element away from the valve seat while said member flexes in response to pressure changes within said chamber to control the position of the valve element with respect to the valve seat, wherein said valve body includes a base incorporating said inlet, said outlet, and said valve seat, a retainer mounted atop said base, said retainer having an

Abstract: The present invention is directed to methods for controlling the flow of fluid and, more particularly, to a method of using triggerable passive valves to control the flow of fluid. In one embodiment of the present invention a method of using triggerable passive valves to control the flow of fluid is described wherein fluid is moved through a passive valve by providing pneumatic pressure between the passive valve and a flow restrictor, the pneumatic pressure exerted causing the pressure exerted by the fluid on the passive valve to exceed the burst pressure of the passive valve.

Abstract: Valve positioning systems may include one or more components and a controller. Components may include one or more electric-to-pressure output converters, relays, gas supplies, and/or actuators. A controller may adjust a position of a valve by sending a signal. The valve positioning system may individually monitor components and determine the condition of each component being individually monitored. The valve positioning system may determine if a component will fail prior to failure and/or determine if a problem will occur in a component prior to the problem occurring.

Abstract: A pipeline (12) for the transportation of a process fluid comprises an autonomous shut-off valve system comprises a shut-off valve (1) including a fluid powered valve actuator (2) moveable between a closed and an open position by means of pressure generated by the process fluid, a pressure tapping (3) in the pipeline upstream of the shut-off valve, a fluid connection to the pressure tapping arranged to deliver process fluid to power opening of the said shut-off valve, at least one pressure sensor (16) arranged in a hydraulic line extending from the pressure tapping, at least one control valve (8A, 8B, 8C) operable to permit or prevent flow of pressurised fluid to the shut-off valve actuator; and a controller (15) arranged to open and close the control valve. The control valve is commanded to open and close when pressure thresholds are reached, the pressure thresholds being detected by the pressure sensor and the control valve being commanded to close by the controller.

Abstract: A vehicle is provided with a controlled internal pressure to preclude intrusion of external atmospheric contaminants. The vehicle has an internally operable egress door. Internal pressure must be maintained low enough to allow occupants to readily open the egress door. A spring-biased poppet valve is used to maintain a requisite very low enclosure-to-atmosphere pressure differential (below 0.2 psid). The valve utilizes a diaphragm and a compression spring as force balancing elements. The compression spring has a spring constant of at least 0.5 pounds per inch.

Abstract: An orifice assembly includes a sleeve and a rod. The sleeve has a first axial end, a second axial end, an outer surface, and a bore that extends through the first and second axial ends. The second axial end defines a first opening and a second opening that extend from the outer surface into the bore. The rod includes a first portion and a second portion that is adapted for linear sliding movement in the bore of the sleeve. The second portion includes an end that cooperates with the first and second openings in the sleeve to define a first variable orifice and a second variable orifice.