Abstract: A flange assembly and related methods of connecting two exhaust pipes together with a flange assembly are provided. The flange assembly includes a first flange having a first mating face and a second flange connected to the first flange, wherein the second flange has a second mating face. A sealing structure is formed with the mating faces of the first and second flanges, wherein the sealing structure comprises a groove positioned on the first mating face and a ridge positioned in the second mating face, wherein the ridge occupies at least a portion of the groove with the first flange connected to the second flange.

Abstract: A dosing module (1) for introducing a reducing agent into an exhaust system of an internal combustion engine for exhaust aftertreatment. The dosing module (1) comprises a flange (20). The flange (20) is secured to a connecting flange (11) on an exhaust pipe. A sealing element (22) located between the flange (20) and the connecting flange (11) is designed as a single layer and separates an interior (26) of the exhaust pipe from an exterior (27) of the exhaust pipe. The sealing element (22) is disposed in the area of the center of gravity (42) of the dosing module (1).

Abstract: An exhaust gas purification device capable of enhancing handling operability such as maintenance of an engine includes two gas purification bodies which purify exhaust gas discharged from the engine, inner cases in which the gas purification bodies are incorporated, and outer cases in which the inner cases are incorporated. The outer cases are arranged side by side in a moving direction of exhaust gas and connected to each other. One of the adjoining inner cases is inserted into the other inner case to form a double-layer structure. A loosely-fitting gap is formed between an inner side surface of the one inner case and an outer side surface of the other inner case.

Abstract: A connection system for carrying a refrigerant may provide a hybrid redundancy in sealing a refrigerant flow from the surround system environment. The connection system may include a first sealing ring of a first type and a second sealing ring of a second type positioned downstream from the first sealing ring. In some embodiments, the first sealing ring may be in a groove positioned around the outside diameter of a male fitting. The second sealing ring may be positioned at an interface between the male fitting and a female fitting. In some embodiments, flanges of each fitting define the interface so that the second sealing ring may be positioned between the flanges of each fitting. The second sealing ring may be selected from a material that has a wider range of operating temperature than the first sealing ring so that in the event of failure in the first sealing ring, the second sealing ring may prevent leakage.

Abstract: A marine riser assembly having a first tubular member having an external surface with a plurality of first axially spaced formations, a second tubular member having an external surface with a plurality of second axially spaced formations thereon, a segmented ring in surrounding relationship to the first and second tubular members, the segmented ring having an inner surface with a plurality of formations engageable with the formations on the first and second tubular members, the engageable formations serving to urge the first and second tubular members toward each other when the segmented ring is subjected to radially inwardly directed compressive forces, a sleeve in surrounding relationship to force the engageable formations together and a seal assembly for sealing against external and internal pressure.

Abstract: A disclosed connector assembly for a refrigerant system mounted within an aircraft includes a metal seal disposed within a seal bore of a connector and compressed against a seal face of a nipple secured to the connector by a threaded member. The connector includes a seal bore that receives the metal seal with the inner portion of the seal bore open to the bore. In one example, the connector and nut are formed from aluminum and the nipple is formed from stainless steel and includes an aluminum coating applied to surfaces in contact with the metal seal and the connector.

Abstract: A method and apparatus for a Boiling Water Reactor (BWR) jet pump slip joint internal seal for an interface between an inlet mixer and a diffuser of a jet pump assembly. The internal seal effectively mitigates leakage and slip joint flow induced vibration (FIV) between the inlet mixer and diffuser to reduce damage to many of the jet pump assembly components. A metallic seal of the slip joint internal seal flares out to conform the internal seal to a range of gap sizes, and compresses or springs back to nominal dimensions as thermal expansion and contraction occurs. The internal seal is self-expanding/self-tightening, as the internal seal flares further outward as a result of the internal pressure caused by flowing fluids in an operating jet pump assembly.

Abstract: A threadless connection for coupling segments of pipe longitudinally end to end includes a pin end having a groove for receiving therein a locking ring. A box end has a groove for receiving the locking ring therein when the pin end is inserted into the box end. The locking ring has an uncompressed diameter selected to exert lateral force on the groove in the box end when assembled to the pin end.

Abstract: A disclosed connector assembly for a refrigerant system mounted within an aircraft includes a metal seal disposed within a seal bore of a connector and compressed against a seal face of a nipple secured to the connector by a threaded member. The connector includes a seal bore that receives the metal seal with the inner portion of the seal bore open to the bore. In one example, the connector and nut are formed from aluminum and the nipple is formed from stainless steel and includes an aluminum coating applied to surfaces in contact with the metal seal and the connector.

Abstract: Each of ridges 7 on respective opposite side surfaces of a gasket 4 has a trapezoidal cross sectional shape defined by an outer tapered face 7a providing an outer peripheral surface, an inner tapered face 7b providing an inner peripheral surface and a flat face 7c providing a top end surface. The hardness of the gasket 4, the angle between the tapered faces 7a, 7b of the ridge 7, the height of the ridge 7 and the area of the flat top end face 7c of the ridge are so determined that the value of thrust for tightening up the coupling is between a predetermined minimum value and a predetermined maximum value.

Abstract: Each of ridges 7 on respective opposite side surfaces of a gasket 4 has a trapezoidal cross sectional shape defined by an outer tapered face 7a providing an outer peripheral surface, an inner tapered face 7b providing an inner peripheral surface and a flat face 7c providing a top end surface. The hardness of the gasket 4, the angle between the tapered faces 7a, 7b of the ridge 7, the height of the ridge 7 and the area of the flat top end face 7c of the ridge are so determined that the value of thrust for tightening up the coupling is between a predetermined minimum value and a predetermined maximum value.

Abstract: A connector assembly and method of creating a connection is described. The connector assembly includes a connector fitting having at least one receiving component on an end of the connector fitting and a gasket having at least one appendage, where the at least one appendage of the gasket engages the at least one receiving component to create an at least temporary secured attachment of the gasket to the connector fitting end.

Abstract: A sealing element including a tube-shaped body of metallic material and first and second male sealing members arranged at a respective end of the body. At least two intermediate members are arranged in series in the body between the first and second male sealing members. Each one of the intermediate members is compressible so as to be capable to store elastic energy when the body is subjected to axial compression and includes a protuberance arranged in the body and extending around the center axis of the body. A coupling device provided with such a sealing element.

Abstract: A female undersea hydraulic coupling member is equipped with a pressure-energized seal configured to seal between the body of the female member and the probe of a corresponding male hydraulic coupling member in response to ambient hydrostatic pressure. In one particular preferred embodiment, the pressure-energized seal is a metal J seal retained within a removable seal cartridge.

Abstract: A connection assembly for pipes is provided. The assembly includes a pipe, a corrugated conduit, a circumferentially contractible seal positioned between portions of the conduit and the pipe, a clamp encircling the conduit, seal and pipe, and a plurality of discrete projections on the inside of the seal to limit the extent of overlap between the pipe and the conduit. The seal is circumferentially contractible to secure the conduit and the pipe together with the seal serving to effect a gas-tight seal while filling the annular gap between the conduit and pipe.

Abstract: A pipe clamp includes a deformable cylindrical sealing sleeve having a continuous side wall with a slotted opening extending 180 degrees around the circumference of the side wall adapted to receive a gate valve plate. The slotted opening has protruding lips bordered by clamping wedges. Clamps are provided for clamping the sealing sleeve to a pipe. Pressure members are provided. A clamping force with pressure members upon the clamping wedges to clamp the lips into a closed position thereby creating a fluid tight seal when the gate valve plate is removed.

Abstract: A flowline connection assembly connects first and second tubular members to each other. Each tubular member has an external flange on its end. A recess is formed in the bore at the end of each of the tubular members. A seal ring extends into each of the conical recesses. A clamp with two halves, each with cam surfaces that engage the flanges and pull the tubular members axially toward each other. Bolts extend from one clamp half into the other. A retainer ring on each bolt retains the bolts with one of the clamp halves.

Abstract: A metallic seal or gasket for use in the joining of cryogenic fluid conduits, the seal or gasket having a generally planar and serpentine periphery defining a central aperture. According to a preferred embodiment, the periphery has at least two opposing elongated serpentine sides and two opposing arcuate ends joining the opposing elongated serpentine sides and is of a hexagonal cross-section.

Abstract: An expansion joint lies between a device and pipe and allows for movement at the joint. Embodiments utilize a case pipe, a sliding ring formed to house seals, and a flange that holds the sliding ring in place. A pipe contacts an inner seal inside the sliding ring which is compressed against the pipe beyond its memory and forms a tight seal, yet allows for pipe to move through the apparatus. At least one outer seal is compressed within its memory which allows for rotation of pipe and/or sliding ring relative to the apparatus about the axis of the pipe. Allows for unlimited travel of pipe and unlimited rotation. The apparatus becomes more efficient as contaminants fill the seals. Works below, at and beyond 1300 degree media, for example any liquid or gas. May be disassembled easily maintained.

Abstract: A trailer hitch assembly includes a receiver portion including a cylindrically-shaped cavity, a bushing member received within the cavity of the receiver portion, and a hitch member that includes a shaft pivotally received within the bushing member. At least a selected one of the bushing member and the shaft is constructed of a material that substantially eliminates the need for using a separately applied lubricant during use of the trailer hitch assembly.

Abstract: An adapter assembly having an intermediate ring and a screw-in part for a fluid plug-in system. The adapter assembly includes an externally threaded portion for threading into a threaded bore and an actuating shoulder. A receiving groove is formed in the transition between the actuating shoulder and the externally threaded portion with a first sealing ring is disposed therein. The intermediate ring fits onto the externally threaded portion and has opposing axially spaced annular portions. A first annular portion cooperates with the receiving groove and the actuating shoulder to form a first sealing chamber for the first sealing ring. A second sealing seat of a second annular portion facing away from the actuating shoulder cooperates with a surrounding surface adjacent to the bore and the externally threaded portion to form a second sealing chamber for the second sealing ring axially spaced from the first sealing chamber.

Abstract: A low profile tension style flexible joint for pneumatic ducting may be useful as, for example, a joint for aircraft engine pneumatic ducting. The joint of the present invention may be used at both ends of a duct that passes high temperature (up to about 1200° F.) and high pressure (up to about 110 psia) compressor air to the combustor of a turbomachine. Some turbomachines, such as the turbo engine of a jet-powered aircraft, require a very short curved duct to fit into an unusually small aircraft installation envelope. Moreover, these installations also require those features found in conventional flex joints, including being able to support the axial load inherent in pressurized ducting systems. Unlike conventional flexible joints, such as ball joints, gimble joints and pressure compensated joints, the low profile tension style flexible joint of the present invention provides a low profile, low weight design with the ability to support the axial load inherent in pressurized ducting systems.

Abstract: A flowline connection assembly connects first and second tubular members to each other. Each tubular member has an external flange on its end. A conical recess is formed in the bore at the end of each of the tubular members. A metal ring has a pair of legs extending in opposite axial directions, each of the legs having a conical outer surface that engages one of the conical recesses. Each ring has an elastomeric seal that seals the recess. A clamp has cam surfaces that engage the flanges and pull the tubular members axially toward each other.

Abstract: Two coupling members are provided in respective butting end faces thereof with annular recessed portions surrounding respective fluid channels thereof and having annular projections each formed in a bottom face of the recessed portion. A gasket comprises a sealing portion having an outside diameter smaller than the diameter of the recessed portions and is positioned between the projections of the coupling members, and a guide has an outside diameter permitting the guide to be fitted into the recessed portions and positioned externally of the sealing portion. The butting end faces of the coupling members are movable into contact with each other when the coupling is tightened up properly. The sealing portion has an annular groove formed in an outer periphery thereof, and the sealing portion and the guide are connected together by a snap ring fitted in the annular groove.

Abstract: A fuel communicating assembly including a base having a wall disposed about a longitudinal axis. The wall having a surface exposed to the longitudinal axis. The surface defining a chamber. The wall having an end that defines an aperture to the chamber. The assembly further including a component having a housing. The housing having an exterior surface. A portion of the exterior surface disposed within the chamber. A metallic member having an inner surface and an outer surface contiguous with the exterior surface of the component. The outer surface is contiguous with the surface of the wall so that the portion of the exterior surface of the component is retained within the chamber and the aperture of the chamber is hermetically sealed. A method of retaining a component within a base is also described.

Abstract: The invention relates to couplings for fluid flowlines and more particularly to couplings that can be dismantled comprising flanges and a static ball-and-socket joint for use with flowlines having a diameter lying in the range 40 mm to 200 mm and transporting fluids (gases or liquids) of high penetrability, at high temperature of up to 800° C., and at high pressure of up to 450×105 Pa. Teh device comprises a flanged coupling device with a static ball-and socket joint comprising a first coupling member (1) having a conical sealing surface (8), a second coupling member (3) having concave sealing surface (10) of spherical shape, a two-barrier metal gasket (2) disposed between the sealing surface (8, 10) of the first and second coupling members (1, 3), and assembly means (4) for assembling the first and second coupling members (1, 3) together so as to hold the gasket (2) between their respective sealing surfaces (8, 10).

Abstract: An improved seal retainer for an undersea hydraulic coupling member, which utilizes metal seals to maintain fluid integrity, is disclosed. The metal seals of the present invention are designed to either create an absolute barrier to fluid flow, or utilize a press or interference fit to create a barrier to fluid flow to ensure fluid integrity between the undersea hydraulic coupling and the environment outside the hydraulic coupling.

Abstract: A threaded joint which economically imparts effective sealing properties to a metal-to-metal seal portion and which can prevent seizing at the time of make-up comprises a steel pipe 1 having at its tip a male thread 1b and an unthreaded sealing surface 1a, and a coupling 2 having on its inner surface a female thread 2b and an unthreaded sealing surface 2a. With the yield pressure of the inner surface of the pipe being Py, (1) the average pressure Pm of the annular contact portion satisfies Pm/Py?3, and the width in the axial direction of the portion which receives a pressure Ps which satisfies Ps/Py?1 in the annular contact portion is at least 1 mm (or at least 2 mm), and the surface roughness Ry of both unthreaded sealing surfaces is at most 25 ?m (or at most 30 ?m), or (2) the relationship between the average pressure Pm of the annular contact portion and the surface roughness Ry (?m) of the unthreaded sealing surface satisfies Pm/Py?0.0032×Ry2+1.

Abstract: The fitting has a high-pressure fuel supply conduit, and the injector has a hollow body having a threaded seat engaged by a threaded portion of the fitting. The fitting has a shoulder located between the threaded portion and another portion of the fitting, and the hollow body has a shoulder on a non-recessed outer surface of the hollow body. The two shoulders are precision machined so they are parallel in use; and the usual high-pressure fuel sealing washer is inserted between the two shoulders so machined. More specifically, the shoulder of the fitting has a groove housing the washer, and the shoulder of the hollow body undergoes circular spot facing to form a series of circular cavities concentric with the axis of the threaded seat and characteristic of Ra=1.6 surface roughness.

Abstract: A connection structure providing a sealed joint between first and second fluid conducting parts has a first seal surface on a first part, a second seal surface on a second part, and an annular elastomeric gasket positioned between the first and second seal surfaces. At least one of the first and second seal surfaces has at least one projection extending from a respective seal surface. The projection is adapted to pierce the elastomeric gasket and abut the opposing seal surfaces upon assembly of the first and second parts at relatively low, hand-tool torque levels.

Abstract: A metal-to-metal sealing element for a wellhead assembly which includes at least first and second adjacent components and first and second generally annular sealing surfaces that are each formed on a corresponding one of the components. The sealing element comprises an annular base, an annular sealing lip which projects radially toward at least one of the first and second sealing surfaces and which comprises a seal retaining groove, a soft metal sealing insert which is disposed within the seal retaining groove and which in use engages the at least one sealing surface, and an annular intermediate portion which extends between the base and the sealing lip. The intermediate portion presses the sealing insert against the at least one sealing surface in an interference fit relationship.

Abstract: An articulating connector system including an active connector coupled to a first line and a hub assembly coupled to a second line. The active connector includes a swivel coupling element intermediate a grip and a ball nose to allow rotational and articulating motion. A seal is coupled to the ball nose and is protected and guided by an alignment lip into mating engagement with a sealing surface defined by the hub. A clamp closes about the swivel coupling element and hub to draw together the seal and sealing surface into sealing contact to connect the first line to the second line.

Abstract: A retrofit fitting for an externally threaded male nut that carries a face seal. The fitting is an adaptor with an internal thread to be threaded onto the male nut and an external thread to receive a female nut. The fitting carries a plurality of blades that engage matching blades on a cage engaged by the female nut. The cage is compressed against a head that bears the face seal by the female nut, so that relative rotation between the heads and face seals is prevented.

Abstract: An end-sided closure of a pipe having the following features: a flanged-socket metallic member one end of which is welded to the pipe to be closed and the other end of which is designed for being orbitally welded to a pipe joining it and the outer surface of which has formed thereon an annular flange which has axially parallel threaded bores at circumferential spacings, a cap-shaped closing member adapted to be placed onto the other end of the flanged-socket member with a ceiling portion and an annular wall portion wherein the inner surface of the ceiling portion is adapted to sealingly bear against the front-end face of the other pipe end and wherein the wall portion has axially parallel through bores which can be aligned with the threaded bores, and headed screws which are adapted to be inserted through the through bores from the ceiling portion and can be turned into the threaded bores wherein the heads of the screws bear against an abutment surface of the sealing portion in order to press the inner sur

Abstract: Couplings and coupling components which prevent relative rotation between tubular members when break away torque forces are applied to the tubular members. In one embodiment, the invention is a locking ring for preventing relative axial rotation between two generally tubular members. The ring is shaped to receive a sealing gasket and has two side faces wherein each side face is shaped to frictionally engage one of the tubular members to thereby prevent relative axial rotation between the tubular members. The invention is also directed to a coupling including a locking ring and a method of making a coupling having a locking ring to prevent relative rotation between the tubular members. In another preferred embodiment, the invention is a coupling comprising two generally tubular members each having a sealing end face, a raised, annular sealing bead, an inner bore, and a frictional surface located radially outward of the sealing bead.

Abstract: A hose for transporting preferably gaseous media at high temperatures and under high pressure has a corrugated interior surface with depressions and elevations, and at least one insertion element that can be inserted in one end. The hose is characterized in that, in the region of contact between the interior surface of the hose and the exterior surface of the insertion element, at least one gasket element of crystalline material is provided. The gasket element is metal, preferably a lead or copper alloy.

Abstract: A female fitting for pipes or tubes, particularly indicated for use in cramped quarters and under highly restrictive environmental conditions, has a split front section threaded with tapered translation-type threads. A hex-nut with commensurate and similarly tapered threads is used to cinch the split front section over an engaging pipe or tube. A circular groove within the fitting can nest an O-ring or other sealing collar. A flange with flattened parallel peripheral zones surround the fitting for reinforcement and to provide a convenient clamping surface. A cutting tool with dual pairs of cutting wheels is used to score two parallel channels around the end of the pipe or tube to receive a first sealing-ring made of compressible material and a second made of the same material as the pipe or tube.

Abstract: An undersea hydraulic coupling member having a ring-shaped seal with multiple scaling surfaces extending radially inwardly therefrom is disclosed. The multiple sealing surfaces help guide the probe of the male coupling member into the female member without the risk of drag or galling of the receiving chamber or metal seal retained therein. The seal has an interfit with reverse inclined shoulders in the female member to restrain the seal from moving radially inwardly due to vacuum or low pressure.

Abstract: An annular metal-to-metal sealing system, for use in wellhead systems and having many other uses, has a metal member defining an annular internal or external sealing surface for which sealing is intended. An annular seal body composed of high strength metal material is positioned in concentric relation with the annular sealing surface and is sufficient flexible to become spring loaded, typically during assembly, for continuous application of a spring force. The annular seal body defines one or more annular seal retainer grooves each having an annular soft metal sealing insert therein, with a portion thereof exposed for sealing engagement with the annular sealing surface. The spring loaded characteristic of the annular seal body applies constant force to maintain the soft metal seal insert in constantly energized sealing relation with the annular sealing surface and maintains effective sealing even when dimensional changes to the sealing surface occur due to temperature or pressure changes.

Abstract: An undersea hydraulic coupling is disclosed having a male member with at least two radial seals around the outer circumference of the probe. The seals on the probe engage the receiving chamber and seal retainer of the female coupling member. When the seals retained in the female coupling member are worn or damaged, the seals on the male coupling member provide the primary sealing mechanism in the coupling. The coupling includes a normally closed poppet valve within each of the male female coupling members.

Abstract: An axial seal assembly is provided at the interface between adjacent wheels and spacers of a gas turbine rotor and disposed about tubes passing through openings in the rotor adjacent the rotor rim and carrying a thermal medium. Each seal assembly includes a support bushing for supporting a land of the thermal medium carrying tube, an axially registering seat bushing disposed in the opposed opening and a frustoconical seal between the seal bushing and seat. The seal bushing includes a radial flange having an annular recess for retaining the outer diameter edge of the seal, while the seat bushing has an axially facing annular surface forming a seat for engagement by the inner diameter edge of the seal.

Abstract: The invention relates to a connecting branch (10) comprising a replaceable insert part (20) which is placed in a chamber (22) in a sealed manner. Said chamber is open in the front and is located inside the connecting branch (10). A ring-shaped sealing surface having a rotating sealing bead (16) is arranged on the insert part (20). The bead can be pressed into a front surface of an axial sealing ring (14) made of a soft metal, said surface being situated opposite the connecting branch, when coupling a connecting nipple (12) to the connecting branch (10). The insert part (20) is advantageously sealed in the chamber (22) by a second axial sealing ring (32) whose sealing surfaces also having sealing beads (34, 36). The insert part (20) can be merely replaced when the sealing bead (16) is corroded or damaged. As a result, a difficult subsequent fashioning of the standard seal bead (16) on the connecting branch (10) is unnecessary.

Abstract: A coupling has a plastic socket part having a connection nipple fitted into an end of one of two tubes to be joined and having an outer surface engaging the lining of the one tube, a socket having an inner surface, and a conductive metallic lining layer on and extending between the inner and outer surface. A plastic plug part has a respective connection nipple fitted into an end of the other of the tubes and has an outer surface engaging the lining of the other tube, a plug having an outer surface and fittable in the socket, and a conductive metallic lining layer on and extending between the outer surfaces of the plug part. An electrically conductive seal ring is fixed in the socket and engages the outer surface of the plug part. The parts are made of polyoxymethylene and/or a fiber-reinforced polyamide.

Abstract: A retainer clip for holding a gasket between the ends of two coupling components includes a first resilient annular member extending circumferentially about two-thirds of a circle, a second resilient annular member having circumferential ends and a discontinuity between the ends, and a bridge connecting the first and second resilient annular members. The bridge has a circumferential extent of less than 45°, and the first resilient annular member is circumferentially expandable without causing the second resilient annular member to expand.

Abstract: A coupling assembly includes first and second coupling members or glands having end faces that sealingly engage opposite faces of an annular gasket. An end face of the coupling member includes a circumferentially continuous seal bead disposed adjacent the bore of the coupling member. A bead thus contacts the gasket along a radially inner region thereof. Disposed over a major portion of the radial face is a substantially planar region. The planar region is adapted to engage the gasket during make-up so that the user encounters an increase or positive feedback of increased torque once the coupling assembly is properly made-up. The end face also includes a raised ring disposed along the radial perimeter. The ring extends outwardly from the end face a dimension slightly greater than that of the bead so that it provides initial engagement with the gasket. This locks the coupling member and gasket against relative rotation during make-up.

Abstract: A flat ring packing to be placed between two flanges comprises two packing layers of packing material and an intermediate ring of metal, which is disposed between the two packing layers and has a common central longitudinal axis therewith. Each packing layer is fixed on the intermediate ring substantially without play radial and parallel to the axis by means of a connection.

Abstract: A pipe joint comprises a pair of tubular joint members, an annular gasket interposed between opposed end faces of the two joint members, and threaded means for joining the two joint members. Each of the joint members is prepared from a stainless steel having a surface with a Vickers hardness of at least 300. The gasket is prepared from a stainless steel comprising, in ratio by weight, 12.90 to 15.00% of Ni, 16.50 to 18.00% of Cr, 2.00 to 3.00% of Mo, up to 0.02% of C, up 0.30% of Si, up to 0.40% of Mn, up to 0.03% of P, up to 0.003% of S, up to 0.25% of Cu and up to 0.01% of Al, the gasket having a surface with a Vickers hardness of 90 to 160.

Abstract: An undersea hydraulic coupling has a bleed port for seawater external to the coupling to enter the bore of the female coupling member when the male member is partially withdrawn from the female member. A ring-shaped radial seal positioned between the coupling members allows fluid to enter through the bleed port and flow into the bore, while sealing against the flow of hydraulic fluid out of the coupling. The bleed port and ring-shaped radial seal provide for seawater to fill the vacuum between the coupling members when they are separated, thereby decreasing the separation force required.

Abstract: An undersea hydraulic coupling having a radial pressure-energized seal with a dovetail interfit is disclosed. The seal has a pair of flexible sealing surfaces for sealing with the male and female coupling members, and a cavity therebetween that is exposed to fluid pressure in the coupling. The outer circumference of the seal has a dovetail interfit between inclined shoulders in the female member bore and on a seal retainer that holds the seal in the bore.

Abstract: Each of seal projections 7, 8 is positioned radially outward of an inner periphery 1a, 2a of abutting end face of each of joint members 7, 8 and has in section a contour which comprises a circular-arc portion 7b, 8b extending radially outward from the abutting end face, and a straight portion 7a, 8a extending from the circular-arc portion 7b, 8b. The circular-arc portion 7b, 8b has a center positioned radially inward of the point of intersection of the circular-arc portion 7b, 8b and the straight portion 7a, 8a. The straight portion 7a, 8a is inclined at 30 to 60 degrees with respect to the direction of axis of the joint member.