Abstract: A gasket and retainer assembly for a tube coupling arranged such that the gasket can be installed into, and removed from, a retained and supported position between the coupling components with a strictly lateral movement. The assembly includes a retainer having a pair of engagement portions located on generally diametrically opposite sides of the gasket to radially grip the associated coupling component.

Abstract: A storage container (12) is filled with a combustible mixture of gases including a flammable gas and a primary gas which contains an oxidizer gas. A fill head (50) has a continuous annular ridge (130) which extends around a gas outlet (132) from the fill head. The ridge (130) indents the material of the storage container (12) around an opening (152) in the storage container through which a flow of gas is directed during filling of a chamber in the storage container to provide a gas tight seal between the ridge and the container.

Abstract: A gasket for use on a exhaust connection between an exhaust manifold and an exhaust pipe includes a spherical sealing portion which mates with sealing portions on both the exhaust manifold and the exhaust pipe. The spherical-to-spherical-to-spherical contact allows adjustment between the various sealing surfaces, while maintaining an adequate seal. Interference fits are utilized to secure the gasket to one of the exhaust manifold and exhaust pipe. Further, a method of forming the gasket involves first drawing a sheet into the general shape, and then punching all required openings in the gasket shape.

Abstract: An undersea hydraulic coupling having a male member with a stepped outer body is inserted into a female member having a bore with stepped internal cylindrical surface. The step in the male member defines first and second external cylindrical surfaces which are slidably received in the female member bore and in a sleeve member before the seals, which are retained by the sleeve member, engage the male member. Thus, the male member is more accurately positioned and guided into the seals, insuring greater seal reliability and longer seal life. The stepped surfaces also help prevent implosion of the seals due to sea pressure when the end of the male member comes out of the seals.

Abstract: A seal for the articulating ball joint of a vehicle exhaust system to prevent exhaust leakage. Vehicle exhaust systems include several connected sections to direct exhaust from the engine through the catalytic converter and out the tail pipe. At least one articulating ball joint is included to compensate for vibrational movement between the engine and the exhaust system. The joint seal of the present invention incorporate a bi-metal body with a first end secured to a portion of the clamp assembly and a second end which seals the gap between the members of the ball joint to prevent exhaust leakage therebetween.

Abstract: A fitting or fitting assembly is provided that comprises a fitting body having an enlarged first end, a nut having a circumferential ridge that has a diameter less than the first end of the fitting body so that the first end prevents the nut from sliding further in one direction, and a ring that is adapted to be assembled onto the exterior surface of the fitting body to prevent the nut from sliding further in a second direction opposite to the first direction. The nut has interior threads that are adapted to receive the external threads of a mated fitting. A method for assembling the fitting comprises the steps of sliding a nut having an internally threaded portion onto a fitting body having an enlarged end that prevents axial movement of the nut in a first direction, and press-fitting a retention ring about the fitting body at a desired position in order to limit the axial movement of the nut in a second direction opposite to the first direction.

Abstract: A pipe joint comprises a pair of tubular joint members having a gasket holding annular projection on each of butting faces thereof, an annular gasket interposed between the butting end faces of the joint members, and a nut for connecting the joint members together. When the nut is tightened up, an indentation is formed in a surface of the gasket pressed by each of the gasket holding projections, and the gasket is pressed also by a portion of the end face of each joint member having no annular projection.

Abstract: An undersea hydraulic coupling have a pair of hollow metal seals which are pressure energized to seal between the male and female members of the coupling. One of the hollow metal seals is configured to expand radially while the second hollow metal seal is compressible along the longitudinal axis of the coupling. These seals provide a fluid tight sealing arrangement upon pressurization of the coupling, without the need for external pre-load devices.

Abstract: A pipe union assembly with embodiments which are capable of use over a very wide temperature range and which may be cycled through temperatures varying widely from the ambient assembly temperature and also over a wide range of pressures without the need to be retightened. Embodiments of the invention also include structures to automatically check the flow of fluids from the components of the pipe union upon disassembly of the union. The pipe union generally comprises one or more fitting members and a sealing member. The sealing member receives a ridge formed on each fitting member in a sealing fashion. One or more external sleeves hold the fitting member and the sealing member in sealing engagement. The materials from which each fitting member and sealing member are fabricated may be chosen so as to exhibit the proper hardness characteristics and thermal expansion coefficients. A compensating washer is also provided to increase compensation for thermal contractions at low temperatures.

Abstract: Herein disclosed is a flared double-wall structure which forms one open end of a metal pipe to be connected to one end of a mating joint. The flared double-wall structure has one annular brim formed on and along the inner sheet face of the double walls and in the open end.

Abstract: A clamp system for maintaining an end of a high temperature fluid bearing tube in substantially sealing engagement with a surface and in substantial alignment with an aperture in the surface positioned substantially transverse to the tube. A bracket member is provided to hold the end of the tube against the surface. An annular flange is provided on the end of the tube, to form the seal and provide a surface against which the bracket member pushes. The annular flange is advantageously configured so as to position the seal radially away from the tube so as to reduce transmission of heat from the fluid within the tube to the seal, to, in turn, protect the material of the mating surfaces from heat degradation.

Abstract: A casing hanger seal has facilities to enable periodic testing from the exterior of the wellhead housing. The casing hanger seal has inner and outer walls separated by a cavity. An energizing member moves downward to force the inner and outer walls into engagement with the casing hanger and bore of the wellhead housing. Test passages extend through the inner and outer walls, energizing member, and wellhead housing. The test passages divide the seal member into primary and secondary seal areas. Applications of test fluid, from the exterior, to the test passages determines whether a leak is present.

Abstract: A metal to metal seal (10) is provided that comprises an annular seat (66), a seal member (90) having annular metal skirt (91) adapted to engage the annular seat (66), an undercut section behind the skirt (91), and an annular retainer member (78) disposed in the undercut section behind the skirt (91), the skirt (91) being adapted to deflect toward the retainer member (78) when pressured against the annular seat (66), the amount of deflection being limited by the angular distance between the skirt (91) and the retainer member (78). An annular stop member is provided (144) for optionally transferring excess bearing load around the skirt (91) and an adjustment member is provided (176) for selectively controlling the portion of the bearing load carried by the skirt (91) and to limit deflection of the skirt. Use of the subject metal to metal seal is (10) as a piston seal in surface controlled subsurface safety valves (38) employed in the oil and gas industry.

Abstract: An undersea hydraulic coupling having a pair of flexible, pressure-energized seals is disclosed. The seals are configured to seal radially between the male and female members of the coupling so that hydraulic fluid does not leak from the annular space between the receiving chamber and outer surface of the male member. The coupling is pressure-balanced for fluid communication through mating radial passages and the annular space between the members.

Abstract: An injector assembly is provided for use with a high heat, high pressure bustion chamber which utilizes a highly corrosive fuel. The injector assembly includes a ceramic injector which has an annular ceramic flange. A metallic retaining apparatus is provided which includes a pair of retainer plates and a tightening device. In a preferred embodiment one of the retainer plates is a retainer ring. With this arrangement the ceramic flange is clamped between the retainer ring and the retainer plate by the tightening device. The retainer ring is provided with an annular groove. An annular spring is disposed within the groove in engagement with the ceramic flange. Because of the different coefficients of expansion the metal of the retaining apparatus will expand away from the ceramic flange when the combustion chamber is operated. When this occurs the annular spring will expand to maintain a high integrity seal between the injector assembly and the combustion chamber.

Abstract: The present invention relates to face seal fittings for conduits or glands which employ metal gaskets. The fitting of the invention uses two annular end formations on each conduit endwall which sequentially engage the gasket to form two independent seals. The fitting is intended to be used in applications which have special cleanliness requirements.

Abstract: A seal for long-time exposures in oil and gas well tools. The seal is adapted for use in a sealed joint between two relatively movable members. In particular, the seal is designed for relatively slidable members. The seal has a body portion with a pair of annular arms extending from opposite sides thereof. A lip on each of the arms is adapted for engaging one of the relatively movable members. An elastomeric sealing element may be disposed in a groove in the body portion for dynamic sealing between the first and second members. Pusher rings may be disposed on opposite sides of the seal so that the seal may be clamped against one of the relatively movable members without the lips or arms longitudinally engaging either of the relatively movable members or a lock ring used to clamp the seal in place.

Abstract: A metallic sealing ring which in radial cross-section is hollow and of sinuous profile having axial end faces sinuously curved so as each to define an axially outward facing deep peripheral groove, the interior of the ring profile being in communication with the exterior thereof.

Abstract: A probe member for an undersea hydraulic coupling is disclosed having at least one circumferential depression in its outer cylindrical body, for disengaging one or more radial seals during insertion or withdrawal of the probe member from the receiving member of a coupling. The disengagement of the radial seals allows seawater to bleed from or into the space between the coupling members and thereby balance the coupling and seals to seawater pressure.

Abstract: A fitting particularly suited for use in an ultraclean environment or a very clean room. The fitting consists of tubular members or glands having annular sealing beads which project from concentric radial sidewalls and a gasket. The sealing beads engage the gasket to form a seal and radial sidewalls engage the gasket to prevent overtightening of the fitting components.

Abstract: An improved waveguide flange is disclosed for high power operation that helps prevent arcs from being initiated at the junctions between waveguide sections. The flanges at the end of the waveguide sections have counterbores surrounding the waveguide tubes. When the sections are bolted together the counterbores form a groove that holds a fully annealed copper gasket. Each counterbore has a beveled step that is specially configured to insure the gasket forms a metal-to-metal vacuum seal without gaps or sharp edges. The resultant inner surface of the waveguide is smooth across the junctions between waveguide sections, and arcing is prevented.

Abstract: An annular metallic seal element for wellhead housings to provide a fluid-tight seal with a well casing that will withstand extreme temperatures and high pressures.

Abstract: The sealing system employs a metal sealing ring having tapered surfaces which are able to slide along tapered sealing surfaces of the pipe forming members in the event of an axial movement of the pipe forming members away from each other, for example under a back fire situation. The metal sealing ring maintains effective sealing pressure and the sealing surfaces of the pipe forming members define an angle therebetween of from 30.degree. to 50.degree.. The sealing ring is made of highly elastic rust-free steel and is of wedge shape.

Abstract: The present invention relates to a union device for pipe joints, where the joint is within the wall thickness of the pipes being joined, and includes a female part (1) and a male part (2), which in substantially complemental implementation permits the male part (2) to be inserted into the female part (1). In the outer and inner peripheral surfaces of the male and female parts there are grooves (5,11) extending around the periphery such as to form a cavity for a locking ring when the joint has been assembled. In this cavity there is a locking ring having a rhomboid form in cross section with cut away portions at the long sides of the two diametrically opposite acute corners and being of a material which retains its shape with a given resiliency. This locking ring is provided with a through slit or with one or more shorter slits from its large end towards its small end.

Abstract: A coupling device for metal tubular members subjected to pressure where abutting coupling members define a V shaped groove. A metal annular V shaped sealing member constructed from resilient metal is disposed in the V shaped groove and arranged so that the sealing member has sealing edge portions which can expand longitudinally and radially to maintain a seal if the coupling members tend to separate or contract in response to pressure.

Abstract: A branch connection for a high pressure fuel rail including a passage through which high pressure fuel flows, and a plurality of through holes formed in the circumferential wall of the passage and including respective pressure receiving surfaces tapering radially outwardly from the passage. The branch connection comprises a branch element including a passage communicated with the passage of the fuel rail. The branch element includes a press head, at one end, engaged with the pressure receiving surface through a bowl-shaped seal so as to threadably secure the branch element to the fuel rail. The seal has a central hole, at least inner and outer peripheral edges of which are engaged with an end surface of the press head and the pressure receiving surface of the through hole in the fuel rail, respectively. The angle between the peripheral surface of the central hole in the seal and the pressure receiving surface is less than 90.degree..

Abstract: A butt welded and lined flange connector allows the joining of pipe sections lined with a brittle material. Spacing and a sleeved liner at the weld end protects the liner during butt welding. A conventional flange face gasket is modified to protrude into the lined zone to perform a dual sealing function. Like conventional flanged joints, the modified gasket forms a seal sandwiched between the flange interface surfaces. However, departing from current practice, the single gasket also fills the gap and seals the liner edges, protecting the pipe sections from the flowing materials. The invention avoids separate putty-like or elastomeric liner seals as well as exotic liner surface configurations. The present invention is expected to be tolerant of severe conditions and cost effective in many applications.

Abstract: A gasket and retainer arrangement for use in a coupling of the type having first and second coupling components with opposed end faces including sealing ribs extending axially therefrom with an annular sealing gasket interposed therebetween comprises a retainer device for maintaining the gasket in a predetermined located position relative to the end face of one of the components. The retainer includes a generally sleeve-like body defining a retaining portion closely received over the one component at an area rearwardly from the associated radial end face. A plurality of axially extending leg portions are spaced about the retaining portion and extend axially beyond the associated end face. The annular sealing gasket has an outer periphery of a diameter at least slightly greater than the inner diameter of the sleeve-like body with recesses formed in the outer periphery to receive the axially extending leg portions whereby the gasket is maintained in aligned relationship with the end face.

Abstract: A body is engaged with a sleeve by a direct sealing coupling. The sleeve has a flange at one end acting as a belleville spring. The flange has a sleeve sealing surface and a rear annular projection. The body has a body sealing surface at one end. The sleeve sealing surface has a conical angle and comes in contact with the body sealing surface by a female nut, a female thread of which is engaged with a male thread of the body, thereby applying fastening force onto the rear annular projection to form sealing between the body and the sleeve.

Abstract: In accordance with this invention, an adjustable coupling device for releasably interconnecting confronting ends of first and second fluid carrying conduits is provided. A bell flange is attached to the confronting end of one of the conduits. This bell flange has an arcuate internal sealing surface adjacent the lip thereof and a recess extending inwardly longitudinally from the arcuate sealing surface. A sealing flange is attached to the confronting end of the other of the conduits and is sized to be received within the bell flange. It also includes a peripheral abutment spaced from the outer end thereof. A sleeve is mounted on the end of the sealing flange and has a curved outer surface and an inner surface engageable with the abutment to limit the inward movement thereof. A sealing ring is mounted on the sealing flange adjacent the sleeve and is engageable with the arcuate sealing surface of the bell flange when the flanges are drawn together.

Abstract: A pipe connector including a main body having a stepped bore in one end for telescopic insertion over the end of a pipe, creating a stepped annular area around the pipe. A slip retaining nut is threaded into the end of the main body around the pipe, closing off the stepped annular area. Slips are carried in a tapered annular space between the nut and pipe. Prior to actuation, the slips are held up in disengaged position by shear pins. A pair of metal seal rings is disposed in the end of the stepped annular area opposite the nut. A pair of dual-acting, hydraulically actuated pistons is disposed in the stepped annular area between the metal seal rings and slips. Hydraulic pressure actuates the upper piston to move upwardly to energize the metal seals, and the lower piston to move downwardly to actuate the slips into gripping engagement with the pipe.

Abstract: A coupling for joining two tubes is manufactured of a material different from the material of the tubes. The coupling includes two parts, which can be coupled to each other. Each part includes a body with an axial bore for receiving an end of the tube. The bore has an inner wall including a ring. The ring is made of a material which can adhere to the material of the tube. Two tubes made of different material can thus be coupled and uncoupled.

Abstract: A tube or pipe coupling joint structure comprises a pair of spaced flange members adapted for relative movement toward each other along a longitudinal axis. Each of the flange members has a face surface which is generally a surface of revolution about the longitudinal axis with the face surfaces on the respective flange members being located in opposed relationship to each other. A relatively smooth thin metal gasket is positioned between the opposed face surfaces of the flange members and each of the face surfaces comprises a sealing protrusion and a stop surface for limiting penetration of the sealing protrusion into the gasket. Moreover, each sealing protrusion is a circumferentially continuous flat and polished narrow sealing band of narrow width lying in a plane which is normal or deviates from normal to the longitudinal axis by no more than about 1 to 3 degrees.

Abstract: Opposed ends of two tubular members are relatively displaced toward opposite sides of an annular seal to deform the seal and reduce the seal bore into approximate or actual alignment with the tubular members bore.

Abstract: The device has a first metallic junction element affixed to a first pipe element and a second metallic junction element affixed to second pipe element. One of the junction elements is provided with an elastic lip cooperating with a frontal face provided on the other junction element.The element provided with an elastic lip has a nozzle element made of a metal or metallic alloy that is compatible from a welding point of view, with the material of the pipe element to which it is joined by welding, and cooperates with a tightening nut, and an end piece having an axial cross-section in the shape of a horizontal u so as to define the said elastic lip, the said end piece being made of a material that is different to that of the nozzle element so as to provide improved mechanical characteristics giving the elasticity that is necessary for the junction, and being affixed to the free end of the nozzle element by diffusion welding.

Abstract: The invention relates to a pipe connection in which an intermediate ring which is provided on its end faces with sealing lips is inserted between the widened pipe ends and clamping means are provided which brace the widened pipe ends and the intermediate ring together in a force-locking manner, the sealing lips of the intermediate ring being plastically deformed.

Abstract: A union joint capable of perfectly hermetically connecting pipes so that a gas passing the pipes never leaks from the junction of the pipes even if the pressure of the gas is as high as 150 kg/cm.sup.2. The union joint comprises a first sleeve hermetically joined to a pipe, a second sleeve hermetically joined to another pipe to be connected to the pipe joined to the first sleeve, one or a plurality of metallic gaskets placed between the respective sealing surfaces of the first and second sleeves so as to be compressed between the sealing surfaces of the first and second sleeves when the first and second sleeves are drawn axially toward each other, a coupling nut for drawing the first and second sleeves axially toward each other, and a thrust bearing interposed between the first sleeve and the coupling nut to allow the coupling nut to be rotated relative to the first sleeve.

Abstract: A low tolerance joint connecting a pair of hollow refractory bricks, e.g., center riser bricks, runner bricks, etc., together for carrying molten metal, e.g., steel, therethrough. Each brick has a pair of ends with a central passageway extending therebetween. One end of one brick comprises a conical walled annular flange projecting therefrom and a shoulder extending about the annular flange. One end of the other brick comprises a matingly shaped circular recess and shoulder extending about the circular recess. The joint comprises the interface between the adjacent surfaces of the annular flange and recess when the flange is located therein. The interface thus formed is an elongated space, free of mortar or other sealing material, into which the molten metal flows to freeze therein and thereby form a seal precluding its egress from the passageway to the ambient surroundings.

Abstract: The present invention relates to an improved seal assembly for sealing between the interior sealing surface of a well housing and the exterior sealing surface of a hanger landed within the well housing and includes a seal body having a pair of outer lips diverging outwardly for sealing against the housing interior sealing surface and an interior series of annular ridges which have a diameter smaller than the outer diameter of the hanger exterior sealing surface, an upper energizer and a lower energizer for coacting with said lips to move the lips into sealing position and to store the energy of setting to ensure sealing engagement of the lips. In some forms of the invention the energy is stored by virture of the lips being of a relatively low yield stength material as compared to the energizers which have a higher yield strength. Also, structure is provided in some of the forms of the invention to store both radial and axial lip loading forces.

Abstract: A spacing ring for placement between a radially inwardly facing annular surface on a first member and a radially outwardly facing annular surface on a second member to maintain the first and second members in predetermined radially spaced relationship. The ring consists of a plurality of matted metal threads formed into an annular configuration. The ring has a radially inwardly facing surface to surroundingly engage the radially outwardly facing annular surface on the second member and a radially outwardly facing surface to be surroundingly engaged by the inwardly facing annular surface of the first member with the radially inwardly facing annular surface on the first member and the radially outwardly facing annular surface on the second member in axially overlapping relationship. The invention also contemplates a method of forming the spacing ring. The wool material is wrapped around an annular surface on a core bar.

Abstract: A method is shown for forming a flange on an end of a plastic pipe liner of the type used to line a tubular member. A reinforced disc having a rigid portion and an elastomeric portion is placed about the liner exterior and moved into position flush with the flanged end of the tubular member. A retaining ring is placed about the reinforced disc and the disc and liner exposed end are heated to render the materials malleable. A forming unit is then used to apply force to the liner to flow the liner into a reformed shape having a greater external diameter than the remainder of the liner. The forming operation also bonds the reinforced disc to the reformed liner end to further resist any tendency of the liner end to be retracted into the interior of the tubular member.

Abstract: A interconnection system for coaxial fluid tubing includes zero-clearance connectors having a metallic innner gasket for sealing an inner passageway for a first fluid and having a elastomeric outer gasket for sealing an outer passageway for a second fluid. The elastomeric outer gasket forms a fluid-tight seal as the connectors are tightened. Further tightening of the connectors engages and seals the metallic inner gasket. Both straight tubing sections and elbows are constructed in a factory setting so that the completed sections can be assembled at a job site without cutting or welding.

Abstract: In a system for providing a direct sealing connection between flat coupling hardware and VCR-type coupling hardware, a gasket is provided having a conical inwardly facing side surface to engage the toroidal projection on the endface of the VCR-type coupling hardware. The opposite side surface of the gasket is provided with an internal shoulder to receive a metal O-ring to be sandwiched between the gasket and the flat end surface of the flat coupling hardware.

Abstract: A two or three piece seal apparatus and method is described for providing a positive seal of threads in extreme temperature ranges up to 2000.degree. F. for at least 20 minutes. A stainless steel compression/retaining nut is utilized in combination with a high temperature alloy ring or diamond-shaped seal to effect sealing of the threads.

Abstract: A combination air seal for opposed flanges of a casing structure containing air at elevated pressure includes rectangular cross-section groove in one face of one of the opposed flanges and a narrow compressible gasket or seal strip in the groove at one side thereof to define an open transverse channel in the groove oriented transversely to the direction of air leakage through the flanges from the elevated pressure conditions in the structure. Air under elevated pressure leaks across the interface of the flanges to be taken up by the open transverse channel and conducted to a lower pressure region of the structure for further utilization. The gasket is adapted to be adequately but not excessively compressed when metal to metal engagement of the flanges is achieved. The compressed gasket prevents excess air in the channel from escaping from the channel to pass across the flange interface and escape from the casing structure.

Abstract: A fusible plug structure is provided for use on a refrigeration system component. Among the features of the invention is means of a novel character for connecting a gasket or sealing member to one end of a fusible plug body, which assures a proper and effective seal when the plug body is assembled with a companion female fitting member fixed to the refrigeration system component. The connecting means markedly facilitates proper placement of the sealing member regardless of the particular position of the female fitting and supporting refrigeration system component. The connecting means may take various forms, and illustrative thereof is a substance such as oil or grease. Alternatively, one end of the fusible plug body may be so configured as to receive the sealing member in close fitting contact therewith. The sealing member itself may be variously configured.

Abstract: A tubular pin member is received within a tubular box member. The pin member includes a reduced diameter portion forming a shoulder having an annular groove in the shoulder. A metal seal ring of aluminum bronze is shrink fitted onto the outer diameter wall of the annular groove. The tubular box member and the tubular pin member have cooperable connection means connecting the tubular members. The metal seal ring sealingly engages the box thereby establishing a metal-to-metal seal between the tubular members. Pressure in the flow bore of the tubular members applies a force to the inner diameter of the metal seal ring to enhance the metal-to-metal sealing engagement between the seal ring and the outer diameter wall and the box.

Abstract: A coupling is provided for interconnecting two tubular parts having opposed ends and shoulders spaced from the ends, and via which force is applicable to urge the opposed ends toward one another. The coupling includes two tubular members defining a longitudinal axis and adapted to coaxially receive the respective parts and to transmit axial force thereto, via the shoulders; a torque isolator assembly including an annulus received against one of the shoulders on one of the members, and generally longitudinal projection means positioned on the one member to block rotation of the annulus relative to the one member, and about the axis; cooperating screw threads on the members adapted to interfit when the members are relatively rotated to make up the coupling; and a pusher surface on the other of the members engagable with the annulus to transmit axial force via the annulus to the one shoulder, when the coupling is made up.

Abstract: A spacing ring for placement between a radially inwardly facing annular surface on a first member and a radially outwardly facing annular surface on a second member to maintain the first and second members in predetermined radially spaced relationship. The ring consists of a plurality of matted threads formed into an annular configuration. The ring has a radially inwardly facing surface to surroundingly engage the radially outwardly facing annular surface on the second member and a radially outwardly facing surface to be surroundingly engaged by the inwardly facing annular surface of the first member with the radially inwardly facing annular surface on the first member and the radially outwardly facing annular surface on the second member in axially overlapping relationship. The invention also contemplates a method of forming the spacing ring. The wool material is wrapped around an annular surface ona core bar.

Abstract: A metal gasket for a face-seal fitting has an outer section in the form of a circular annulus, an inner section in the form of a circular annulus and having a shorter axial dimension than the outer section. The inner section and outer sections are joined by a tapered section having conical faces on opposite sides thereof facing toward the axis of the gasket. A method of prolonging the useful life of a tubular element in a face seal fitting involves repeatedly engaging an end of the tubular element with the conical face and, when the end of the tubular element wears, engaging the end with a radial face adjacent to the conical face. .Iadd.