Abstract: A stem shoulder seal with double rings is composed of a sealing ring, a clamping ring and a spherical or conical stem shoulder, and the sealing ring is of a self-energized seal designed to its ultimate allowable strength and automatically free of any load beyond its ultimate strength. An assembly of independent dual stem seals, consisting of a stem shoulder seal with double rings, a stem cylinder seal with triangular sections and an isolating mating, can ensure that a stem has three seals which get well seated automatically at the same time to bear an identical ultimate medium pressure independently or without any mutual interference in service when assembled to the extent that the stem operating torque is just definitely increased, thereby ensuring that a stem sealing has a triple safety.

Abstract: A flow control valve in which corrosion is less likely to occur in the vicinity of a radial step portion in a gas passage of a housing and a method for manufacturing the same are provided. A flow control valve includes: a housing formed with a gas passage including a first cylinder member accommodating portion, a second cylinder member accommodating portion, and a radial step portion; a first cylinder member accommodated in the first cylinder member accommodating portion; a second cylinder member accommodated in the second cylinder member accommodating portion; and a valve body that is rotatably arranged inside the first cylinder member and the second cylinder member in the radial direction. The housing is formed of cast iron. At least surfaces of the first cylinder member and the second cylinder member are formed of a highly corrosion resistant material.

Abstract: A floating ball valve has a metal multiple component seat installed in the seat pocket. The multiple component seat further includes a support ring and at least one seal element. The support ring and the seal element are juxtaposed and both are adjacent to the ball when the floating ball valve is in a closed position. The support ring is in a overlapping complimentary position with respect to the seal element, the seal element having greater elasticity than the support ring and the support ring having a greater load bearing strength than the seal element.

Abstract: Seals for use in valves are described. An example seal includes a ring-shaped cartridge. The cartridge has a first portion and a second portion. The first and second portions hold a sealing portion, and the first and second portions have respective first and second curved surfaces adjacent to a sealing surface of the sealing portion. Radii of curvature of the curved surfaces enable an initial point of contact between a flow control member and the cartridge to be on the sealing surface when the flow control member moves to a closed position.

Abstract: A fluid control valve includes: a valve housing having an inlet port and an outlet port; a drive source mounted on the valve housing; a valve shaft configured to be moved by the drive source; and a valve member mounted so as to extend radially with respect to an axial center of the valve shaft, wherein the valve member includes: a valve frame having a cylindrical portion configured to allow insertion of the valve shaft, and a seal member mounted on the extending portion and configured to be capable of coming into abutment with the valve seat, a portion of the valve shaft housed in the mounting portion is formed with a through hole in the direction orthogonal to the axial center, and a rotatable spherical body is arranged in the through hole, and the mounting portion is fixed to the spherical body by caulking.

Abstract: A seal for an air valve having a valve shaft rotatably carried in a bore formed in a body and a valve head carried by the valve shaft to control air flow through an air passage as the valve shaft is rotated. The seal may include a pair of spaced apart sealing members adapted to engage the body within the air passage to seal a junction between the valve and air passage. The seal may also include an intermediate member between and interconnecting the sealing members, where the intermediate member is flexible to permit movement of at least a portion of the sealing members toward each other and the intermediate member is also resilient to yieldably bias the sealing members away from each other at least when the sealing members are displaced toward each other.

Abstract: A bellows energized seal assembly includes a seal body, a main seal that is axially slidable within the seal body, and a bellows connected to the seal body and the main seal. The bellows both biases the main seal and provides a seal between the seal body and the main seal.

Abstract: A valve 33 has a deformed circular shape such that a diameter in an axis orthogonal direction that is orthogonal to a rotation center axis X is longer than that in an axial direction that is parallel to the rotation center axis X, and a front surface of a semicircle on one side of the valve and a rear surface of a semicircle on the other side thereof about the rotation center axis X as a boundary are abutted against valve seats 34a.

Abstract: Seals, ball valve assemblies, and methods of operating ball valves assemblies are provided. The seal includes an annular jacket, a restrictor, and a spring energizer. The annular jacket includes a first annular pocket and a second annular pocket. The restrictor is disposed in the first annular pocket and is capable of restricting shrinkage of the first annular pocket to a predetermined diameter range, if the seal is exposed to a temperature within a predetermined temperature range. The spring energizer is disposed in the second annular pocket and is configured to supply a force against the annular jacket to maintain the seal against a contact surface.

Abstract: Rotary valves are disclosed, comprising a seal sheet affixed to a rotor. At least some area, namely a “rotor plate surface mating area” is provided, over which a seal sheet anchoring assembly can directly abut, along a planar portion, the rotor plate surface that is in contact with the seal sheet. This advantageously provides an area of direct contacting between the seal sheet anchoring assembly, or one of its components, and the rotor plate, with the abutting surfaces being defined by consistently rigid materials (e.g., metals such as stainless steel) that undergo substantially no deformation, compression, or softening over conditions of normal operation.

Abstract: The present invention is directed to an injection molding valve configured to prevent the leaking or stringing of injected thermoplastic from the valve. The valve includes a housing having a first bore along a length thereof and a second bore intersecting the first bore. A rotatable member is inserted through the second bore and is in communication with a lever for the actuation thereof. The rotatable member includes a hole therethrough such that when the hole is aligned with the first bore, thermoplastic may travel freely through the first bore. The second bore further includes at least one groove in communication with a port for receiving injected thermoplastic. The injected thermoplastic is hardened to form an seal therein and configured to prevent thermoplastic from leaking out of the valve housing.

Abstract: Flexible seals for process control valves are disclosed. An example disclosed seal includes a seal for use with a butterfly valve. The example seal includes a substantially flexible ring-shaped carrier configured to be fixed within the butterfly valve and to surround a flow control aperture therein. Additionally, the seal includes a ring-shaped cartridge coupled to an inner diameter of the ring-shaped carrier. The cartridge includes a first portion and a second portion coupled to the first portion to define a circumferential opening to hold a seal ring.

Abstract: Butterfly valve plate sealing assemblies are provided that include a sealing ring and a retention spacer disposed at least partially within a sealing ring groove formed about a periphery of a butterfly valve plate. The sealing ring includes a first portion, a second portion configured substantially perpendicular to the first portion, and a substantially L-shaped cross-section. The sealing ring is positioned at least partially within a groove opening and a groove body defining the sealing ring groove. The retention spacer is positioned at least partially within the groove opening and adjacent the first portion of the sealing ring. The retention spacer is configured to limit expansion of the sealing ring when under the influence of a pressurized fluid flow. The second portion of the sealing ring may be configured to optimize stiffness for a desired sealing ring tension.

Abstract: A differential pressure sealing device for use with ball valves that utilizes the pressure of the fluid being communicated in a piping system to increase the sealing force created by the sealing device. Fluid being communicated through a ball valve is provided to a sealing device that includes some type of element for creating a bias force. The pressure of the fluid being communicated increases the sealing pressure created by the sealing device. In this manner, the bias force created in the sealing device benefits from the pressure of the fluid being communicated to enhance the sealing when used with a ball valve or similar component.

Abstract: A plenum assembly for carrying air in a supply system includes a duct including an opening formed with an inner surface through which air can flow; a door supported for movement between multiple positions which distributes air to the desired output path; and a seal secured to the door. In a vehicles HVAC system, numerous doors are utilized to provide comfort to the passengers based upon user input. The potential exists that some positions of the doors my lead to unwanted noise. A modification to the seal of the door with variable gap widths alleviates this issue and improves satisfaction.

Abstract: The disclosed embodiments include systems and methods for retaining a seat insert of a ball valve in place within a seat ring of the ball valve. In particular, the seat insert is an annular ring having a tapered section on an outer wall of the annular ring. The tapered section of the seat insert is configured to mate with a shoulder in an outer surface of a profiled groove of the seat ring. The seat insert snaps into the profiled groove with the shoulder, thereby preventing axial movement of the seat insert with respect to the profiled groove of the seat ring. In addition, a locking ring also fits within the profiled groove of the seat ring to prevent axial and radial movement of the seat insert with respect to the profiled groove of the seat ring. More specifically, once the seat insert has been snapped into place within the profiled groove of the seat ring, the locking ring is also inserted into the profiled groove of the seat ring.

Abstract: An upstream seat ring and an auxiliary seat ring, which improve valve's capability resistant to erosion by the fluid carrying solid particles or containing liquid drops. One end of the auxiliary seat ring passes through bore of the upstream seat ring and the other end is fixed in the pocket of the valve upstream passageway. There are many bar barriers or analogous mechanism with rectangular, tooth-like or any other geometrical shapes cross-section around the circumferential surface of their bores, which are radially concaved inward or projected outward from the circumferential surface, are longitudinally extended an overall distance from one radial end face of the seats to opposite radial end face or a distance from the radial end face next to the upstream surface of the valve closure member towards the opposite radial end face, and spaced each other radially.

Abstract: A ball valve or any other type of valve in which sealing surface of the seat ring and surface of closure member keep relative sliding contact during opening and closing movement of the valves. One or more annular grooves cut into sealing surface of the seat ring around it's bore are filled with lubricant or grease used for lubricating the surfaces so as to avoid or mitigate their abrasive wear or galling caused by frictional heat.

Abstract: Embodiments and methods are disclosed herein that relate to a valve assembly. The valve assembly includes a housing having a passage formed therethrough, and a valve ball having a through hole and disposed in the housing, in which the valve ball is rotatable between an open position that has the through hole aligned with the passage and a closed position that has the through hole misaligned with the passage. The valve assembly further includes a seat having a first tapered surface and disposed in the housing adjacent to the valve ball, wherein the seat is biased towards the valve ball, and a seat holder having a second tapered surface and disposed in the housing adjacent to the seat such that the first tapered surface of the seat is disposed adjacent to the second tapered surface of the seat holder.

Abstract: In an embodiment of the present invention, a valve seal for a ball valve includes a ball configured to mate with a tail piece, an annular seat ring to facilitate the mating of the ball with the tail piece, the seat ring having an angled wall having a first groove for accommodating a first seal and a second groove for accommodating a second seal, the first seal having a different Young's modulus from the second seal.

Abstract: The resilient seated butterfly valve has a common spherical center for receiving either an on-center or off-center disc, both of which are rotatably mounted in the body. A seal has a seat spherical surface. The seal is affixed to the circumference of the valve chamber. It has an on-center seal region for engagement with the on-center spherical sealing edge of the on-center disc. The seal has an off-center seal region for engagement with the off-center spherical sealing edge of the off-center disc. The seal may include an outlet flange, an outlet ramp, an inlet ramp, and an inlet flange. The front face of the seal for the off-center disc extends beyond the position of the front face of the seal for the on-center disc.

Abstract: There is provided a flow path opening/closing apparatus that can enhance airtightness so as to be capable of being used for a high-speed processing under a high pressure, while keeping advantages, which are a non-contact valve element, high exhausting capability, and high response speed. A butterfly valve includes a body having a flow path through which a fluid flows; and a valve element that can rotate in the flow path about a rotation axis vertical to the flow path, wherein a seal length extending wall for extending a seal length in a direction of the flow path at a gap, which is formed between the body and the valve element when the valve element is fully closed, is formed to project along an edge of the valve element.

Abstract: The invention relates to a passive valve for multi-valve devices for sealing a container or a line. According to one aspect of the invention, the passive valve is free of bearing supports which protrude in a positive sense out of the passive valve. The invention also relates to a multi-valve device for contamination-free connection of two containers or two lines with partial valves that can be rotated about a single axis. According to this aspect of the invention, at least three partial valves, which are arranged essentially parallel to one another and can be put under tension so they can be sealed with respect to their surroundings, can be rotated about the single shared axis.

Abstract: Aspects of the invention are associated with the discovery of methods for operating rotary valves that reduce or minimize wear of the seal sheet, which is often the limiting factor in overall processing capability of the valve. The control of certain parameters associated with the rotary valve operation, and particularly the seating pressure of the seal sheet (e.g., the dome pressure), can extend the useful life of the seal sheet, thereby avoiding excessive maintenance and downtime costs. In preferred embodiments, control is on a real time basis.

Abstract: A high temperature ball valve seal is disclosed that achieves Class IV shutoff for operating temperatures above 550 degrees F. The ball valve seal includes a C-seal positioned between a main seal and a seal housing to prevent fluid from flowing through a secondary flowpath when the ball valve is in a closed position.

Abstract: The invention relates to a sealing arrangement in a rotating control valve of a pressure fluid-operated percussion device, to which percussion device a tool is mountable movable in its longitudinal direction, the percussion device containing a work chamber and a transmission piston mounted movable to compress the tool suddenly to generate a stress pulse to the tool, inlet and outlet channels for conducting pressure fluid to the percussion device and away from it, and a control valve having a rotating switch member with channels to connect inlet and outlet channels through the channels of the switch member to alternately conduct the pressure fluid through the channels to the work chamber and, correspondingly, away from the work chamber, and in the inlet channel of the pressure fluid at the switch member side end thereof at least one sealing sleeve for the purpose of sealing the inlet channel to the switch member.

Abstract: A valve element mechanism for an exhaust gas circulation valve has: a primary eccentricity A causing a center O of a support shaft 4 rotatably provided in a housing 2 to separate from a centerline P of a seal surface 2b of a valve seat 2a with which a valve element 5 opening and closing a fluid passage by being rotated by the support shaft 4 contacts; a secondary eccentricity B causing the center O of the support shaft 4 to separate from a centerline Q of the housing 2, and a tertiary eccentricity C causing an apex G of a cone shape 6 defining a seal surface 5a of the valve element 5 and the seal surface 2b of the valve sheet 2a to position at a side opposite from the support shaft 4 and to tilt against a centerline of the housing 2.

Abstract: A fluid flow control device includes a valve body, a bonnet, a control assembly, and a seal assembly. The valve body defines an inlet portion, an outlet portion, a bonnet opening, and a fluid flow path extending between the inlet portion and the outlet portion. The bonnet is disposed in the bonnet opening. The control assembly is at least partly supported by the bonnet, and includes a ball element disposed within the valve body and rotatable between an open position and a closed position. The valve body defines an internal recess at a location downstream from the inlet portion and adjacent the bonnet opening. The seal assembly is disposed within the internal recess and includes a movable sleeve seal, a retaining device, and one or more sealing elements for preventing leakage between the sleeve seal and the retaining device and/or the valve body.

Abstract: A ball valve sealing ring is provided for sealing between a ball valve member a valve body. The sealing ring may comprise a ring body having a ball valve member-contacting surface and one or more valve body-contacting shoulders for contacting the valve seat. The sealing ring may comprise a resilient ring core for providing bending resistance. The resilient ring core may be at least partially conical and may have a curved cross-section with a convex side oriented towards the member-contacting surface. The cross section may be of a geometry corresponding to the outer contour of the ring body or shoulders and may have ends bent towards the member-contacting surface. The ring core may also have a plurality of apertures spaced about its circumference. The sealing ring may be elastically deflected upon contact with the valve member. Also provided is a ball valve seating arrangement comprising the aforementioned sealing ring.

Abstract: A rotary valve comprising sliding members for supplying treatment gas containing water vapor to a plurality of treatment processes is provided. The rotary valve comprises sliding members (1, 2; 4, 6), through which open flow passages (8, 9, 10), having sliding surfaces slidable to each other and a mechanical seal mechanism for switching the flow passages (8, 9, 10) while sealing fluid by preliminarily pressing the sliding surfaces, wherein the sliding surface of each sliding members (1, 2; 4, 6) is made of hydrophobic material (2, 4) different in hardness from the other.

Abstract: The present invention provides a robust, durable and reliable cylindrical valve having closable, radially extending openings for use in cementing, injection, including hydraulic fracturing, and production in wells having high pressures and large pressure differences. The valve may comprise scraping rings in order to remove deposits and the like when it is to be closed after use. Magnets or other suitable means indicates whether the valve is in an open or closed position.

Abstract: A ball valve (10) for sealing a conduit (12) is described. The ball valve includes a housing having a throughbore and a valve seat. An apertured ball element (18) is mounted within the housing and is rotatable about an axis of rotation (38) between a throughbore open and a throughbore closed position. The apertured ball element (18) has a first portion (20) and a second portion (22) coupled together which are rotatable and moveable relative to each other. The first portion has a sealing surface for engaging with the valve seat. In use, in the throughbore closed position, the second portion is moveable relative to the first portion to axially displace the first portion from the axis of rotation towards the valve seat such that the sealing surface on the first portion of the apertured ball forms a seal with valve seat.

Abstract: A rotating valve assembly includes an inner cup having at least one inlet port; an outer cup having at least one inlet port, the outer cup rotatably mounted concentric with the inner cup by a bearing arrangement; and a cooling system located between the inner cup and the bearing arrangement for providing a thermal barrier between the inner cup and the bearing arrangement. The valve assembly also includes a labyrinth sealing arrangement located around the at least one inlet port of one of the inner and outer cups for preventing leakage of pressure waves generated by detonations or quasi-detonations within a combustion chamber of the inner cup.

Abstract: A rotary valve includes a main body provided with a valve chamber for receiving a plate valve, formed with an annular neck and bored with an intermediate hole extending downward to the valve chamber for positioning a valve rod, which is disposed in the intermediate hole when the main body is being shaped. A seal washer has its outer annular side provided with a serrated surface so that, when shaped, the main body can be combined with the serrated surface to let the seal washer covered by the inner annular wall of the valve chamber. The seal washer has an inner annular side symmetrically formed with an upper and a lower small flat surface respectively matching with an upper and a lower flat surface of the valve plate, having an upper and a lower side respectively bored with a hole for a valve rod to be inserted therein and fixed with the valve plate.

Abstract: An automatic vacuum-relief apparatus for liquid suction systems includes a vessel defining a chamber filled with liquid in communication with a liquid flow line, a rotary shaft extending through the chamber to support a valve device adjacent to the liquid flow line and to move the valve device to open a relief-air flow channel to relieve increased suction caused by inlet blockage, and a piston on the rotary shaft responsive to suction increases within the liquid flow line and chamber to actuate shaft rotation. The valve device, chamber and relief-air flow channel are configured and arranged to cause a spurt of liquid from the chamber into the inlet while the valve device is moving from its isolating position toward its opening position upon inlet blockage, whereby the spurt of liquid pushes the blockage away from the inlet and the relief air reduces the suction.

Abstract: A floating ball valve has a metal multiple component seat installed in the seat pocket. The multiple component seat further includes a support ring and at least one seal element. The support ring and the seal element are juxtaposed and both are adjacent to the ball when the floating ball valve is in a closed position. The support ring is in a overlapping complimentary position with respect to the seal element, the seal element having greater elasticity than the support ring and the support ring having a greater load bearing strength than the seal element.

Abstract: A ball valve comprising a housing, a ball seat disposed within the housing, and a ball rotatably movable within the housing, and engageable with the ball seat in order to provide a seal within the ball valve and the ball seat, wherein the ball seat comprises multiple seat surfaces independently capable of engaging the ball, a first seat surface engaging the ball to form a first seal, and being arranged such that pressure acting from above pushes the first seat surface against the ball; a second seat surface being movable relative to the first seat surface and engaging the ball to form a second seal, the second seat surface being arranged such that pressure acting from below causes the second seat surface to move relative to the first seat surface and pushes the second seat surface into contact with the ball.

Abstract: A valve arrangement has an annular housing with valve seat and a two-part valve plate that is rotatable about an axis. The seat is in the form of a disk including two adjacent openings with a web between and the axis is parallel to the web. The two parts of the valve plate are next to each other with their planes parallel and offset in a perpendicular direction. They are connected to each other through one of the openings by a connection piece extending through the one opening. In a closed position for the valve, the valve plate part are respectively positioned on opposite sides of the valve seat and cover and seal the respective openings due to a seal that is between the valve plate parts and the valve seat.

Abstract: A ball valve having improved sealing between the valve member and the valve body is presented. Improved sealing is realized by providing a sealing member that is allowed to float on the outer surface of the valve member in the closed position. By being able to float on the outer surface, the sealing member can compensate for any variations in the valve member as a result of machining tolerances or variations in position of the valve member due to changes in pressure within the valve, thereby providing dynamic sealing The dynamic sealing is also provided by configuring the valve member such that it causes the sealing member to be exposed to a higher biasing force in the closed position than in the open position.

Abstract: A shear valve assembly includes a stationary valve manifold having a manifold planar surface containing a plurality of manifold input ports and one or more manifold output ports, a movable valve switch having a switch planar surface in slidable, interactive contact with the manifold planar surface forming an interactive contact junction, the switch planar surface having a fluid switching channel capable of connecting one of the plurality of manifold input ports with one of the one or more manifold output ports, a surface modifying component disposed at the interactive contact junction that provides a period of extended useful life of the manifold planar surface and the switch planar surface beyond the useful life of pre-lubricated interactive contact junction, a drive shaft connected to the valve switch, and a valve housing supporting the stationary valve manifold, the movable valve switch, and the drive shaft.

Abstract: A gas separation device is disclosed. In particular, seal assemblies and adsorbent element constructions for a gas separation device such as a pressure swing adsorption device are disclosed. The seal assembly can be part of a rotary valve and can include a seal backer and a floating seal positioned within a bore in the seal backer. The floating seal is configured to press towards and seal against an adjacent rotor. Valve action is provided as apertures in the floating seal and rotor are brought into and then out of alignment as a result of relative rotation therebetween. The seal assembly can include two types of gas chambers to apply balanced sealing pressures over the sealing surface of the valve, one type configured to receive pressurized process gas from within the device and the other configured to receive gas from an independently controlled pressurized gas source.

Abstract: A pressure differential valve apparatus that includes a valve, the valve having a valve head and a valve stem connected perpendicular to the valve head, the valve head having a valve face with an opening that continues inside an interior of the valve head to an intersection with the valve stem and along a length of the valve stem to a top of the valve stem, wherein the apparatus allows unobstructed pressure readings when the valve face is rotated in a radial direction within an area of flow of a cylinder head.

Abstract: A valve seal for use with a valve having a valve element including a plurality of radiused corners. The valve element is rotatably mounted within a frame disposed in a flowbody. The valve seal including a plurality of curved portions in cooperative alignment with the radiused corners of the valve element. The valve seal being partially disposed within a mounting groove formed in an edge surface about a substantial portion of the valve element. A plurality of flexure joints are formed in the seal member and in spaced relation from the curved portions. The plurality of flexure joints providing spring loading of the seal relative to the frame when the valve element is in a closed position.

Abstract: A typical rotary face seal employs a seal ring rotating relative to a sealing surface and also employs means to urge the seal ring towards the sealing surface in order to effect a seal. The seal ring may itself comprise a seal face bonded to a backing ring. In certain applications, the seal face may deform significantly as a result of the temperature variations experienced and an undesirable crowning of the seal face may occur. Such crowning may be reduced by employing an improved seal ring with anti-crowning features in which the thickness of an edge of the seal face is different from that in the middle of the seal face, or in which a relief slot is employed in the seal face. The improved seal ring is particularly suited for rotary face seals used in a rotary valve in a rotary gas separation device.

Abstract: Ball valves that include a gland that is interposed between a spring and a seat. The ball valves include a valve body, a ball, a valve seat, and an annular spring. The spring urges the gland member toward the valve seat to urge the valve seat toward the ball.

Abstract: A valve arrangement includes an inlet conduit defining an inlet passage adapted for communication with a supply of pressurized motive fluid, a first planar surface spaced radially from the inlet conduit, first and second supply passages communicating through the first planar surface, and a rotary valve. The rotary valve includes a second planar surface abutting against the first planar surface and a valve passage communicating through the second planar surface. The rotary valve is rotatable to place the inlet passage in communication with a selected one of the first and second supply passages through the valve passage, and is adapted to conduct the pressurized motive fluid from the inlet passage to the selected one of the first and second supply passages.

Abstract: A shaft protection washer to protect a rotating shaft in a “measurement while drilling” (MWD) tool. Use of the shaft protection washer renders the rotating shaft less susceptible to erosion from the drilling fluid flowing between the rotating component and the stationary component.

Abstract: There is a closure member for rotating or reciprocating movement between upstream and downstream passageways of a valve. A device, which consists of two or more elongated tubes whose cross sections form up into one or more files in moving direction of the closure member to divide the upstream passageway into many channels capable of leading the fluid to flow through, is disposed in the upstream passageway of the valve upstream of the closure member, consequently the upstream surface of the closure member can respectively open or close each channel in sequence while the closure member is rotating or reciprocating in the valve.

Abstract: A ball valve having reduced torque requirements for rotation is presented. Torque reduction is realized by providing a shaped sealing back member to provide a back force behind essentially the entire sealing surface of the downstream seal. Torque reduction is also realized by providing a dynamic sealing configuration that varies the sealing force over the valve's operating pressure conditions. An initial bias sealing force is applied by a spring member which also provides a low uniform as-assembled valve torque. As fluid pressure increases, the sealing pressure also increases as an o-ring is forced along a ramped surface of the seal. As inlet pressure decreases, the o-ring is allowed to back down the ramped surface to reduce the sealing force against the valve member. This sealing configuration allows for reverse flow or improper installation of the ball valve, and bottoms out to maintain a sealing force at higher back pressure conditions.

Abstract: Relief valve in a turbomachine, comprising a gate (116) designed to be mounted so as to pivot about a shaft (120) for the opening and closing of an orifice for the passage of air, a seal (152) and means (158) for attaching the seal to the peripheral edge of the gate, the gate and the attachment means being made of a plastic and formed of a single piece or secured to one another by welding or bonding.