Abstract: An annular gasket for affecting a watertight seal between two sections of corrugated pipe. The gasket comprises a seating portion dimensioned to fit within an annular recess in one of the mated sections of corrugated pipe, and a sealing portion integrally molded with the seating portion. The sealing portion includes a first shoulder portion, a second shoulder portion, and an arcuate surface extending between the first and second shoulder portions. The mass of the seating portion is less than the mass of the sealing portion.

Abstract: This invention relates to a construction for fitting to a structural member in particular to a construction for routing a conduit or the like through a structural member where the integrity of the seal made by the structural member must be maintained. The construction having an annular bush (50) for fitting tightly in an aperture (43) defined in a structural member, the annular bush (50) being expandable radially when located in the aperture (43) by the action of a mandrel being passed through a longitudinal passageway defined by the bush whereby to exert a compressive force upon the region of the structural member surrounding the bush (50), wherein the bush (50) has a coupling for sealable attachment of a conduit to the bush (50).

Abstract: A leaktight coupling between channels formed in two pieces that bear against each other via an intermediate block having at least one duct passing therethrough suitable for putting the respective channels in each of the pieces into communication with one another, the duct forming a housing for an insert provided with beads. The intermediate block has a tubular insert and a sealing device positioned in register with one of the pieces that is to bear against the intermediate block. The beads of the tubular insert are compressed between a shoulder formed in the duct and the other one of the pieces that is to bear against said intermediate block once the intermediate block is mounted between the two pieces.

Abstract: An improved pipe belling process is shown which a gasket is installed on the outer working surface of a forming mandrel at one circumferential location. The heated socket end of a thermoplastic pipe is forced over the mandrel exterior and over the gasket causing the heated socket end of the pipe to flow over the gasket and form a retention groove for retaining the gasket before again contacting the working surface of the mandrel. The heated end of the pipe is cooled and retracted from the working surface of the mandrel. The gasket has a special anti-corrosion and anti-friction coating applied to portions of the exterior thereof.

Abstract: A seal device is constituted of a plurality of seal tubes. After a connected-tube body having base members disposed at a fore end and a rear end is inserted into a fluid passage such as a tubular member, the seal tubes are expanded by injecting gaseous nitrogen into each of the seal tubes. The intermediate portions of the seal tubes along a longitudinal direction are press-fitted to the inner surface of the fluid passage over the entire circumference thereof, whereby the fluid passage is sealed. Since the connected-tube body is easily bent in the vicinity of a connecting base member between the tubes, the connected-tube body can be easily curved along the fluid passage, thus facilitating an operation for inserting the connected-tube body into the fluid passage and also enhancing a sealing property with respect to the fluid passage.

Abstract: The present invention relates to a sealing device for sealing a line relative to a line duct. The line is introducible at least partially into the line duct. A substantially tubular seal is disposed between the line and the line duct. The present invention further relates to a plug-in connector, which is connected to the line duct and comprises a sealing device. In order to provide a sealing device, by means of which the sealing between a line and a line duct may be improved and/or improved strain relief of the line is enabled, at least one sealing lip is formed on the inner and/or outer wall of a seal belonging to the sealing device.

Abstract: A seal is provided to seal the area between a cable containing optic fibers and the terminal end of a conduit through which the cable runs. The seal consists of a resilient gasket and a supporting structure and a cam. The seal assembly, encompassing the cable, is inserted into the terminal end of a conduit that houses the cable. Actuation of a cam compresses a gasket into sealing contact with the cable and with the conduit, thereby sealing the terminal end of the conduit from entry of contaminants.

Abstract: A seal for a drain that includes a seal body having an annular portion and an integral disk portion. An outer sealing surface and inner sealing surface are defined on the annular portion. A handle extends from a first surface of the disk portion. The disk portion defines at least one scribe line adapted to facilitate removal of the disk portion from the annular portion when a pulling force is applied to the handle.

Abstract: A self-adhesive gasket having a pressure sensitive adhesive on one side or on both sides can be used in place of plumbers putty to seal sinks to countertops, faucets to sinks, and strainers and pop ups to sinks and tubs. The gasket is preferably preformed from a flexible cellular plastic, preferably a closed cell urethane foam. The gasket may be used in a multitude of plumbing application to form a liquid seal.

Abstract: A unitary removable barrier for installation in a cylindrical water line to selectively block the water line to passage of water therethrough. The unitary removable barrier is composed of a single piece rubber body having at least one cylindrical section sized to receive upstream and downstream pipes of the water line. A unitary rubber planar disc molded with the cylindrical section is of a circular circumference and which completely blocks the water line but which is selectively removable from the cylindrical section thus removing the barrier to the passage of the waste through the line.

Abstract: A running fluid seal arrangement (10) includes a passage for receiving cable (12) with chambers (20,21 and 22). Water at a higher pressure than gas in main (11) is pumped via pump (26) into chamber (21) from a reservoir (27). A mixture of gas and water from the interface in the region of chamber (20) is passed to a sealed pressure vessel (28). Water therefrom can pass back to reservoir via float valve (29). Wiper seals (30,36 and 37) can also be provided.

Abstract: A high pressure seal consists of a minimal convex excess which induces a plastic-elastic deformation on the flat opposing surface. The excess can also be formed by means of a ring with a circular cross section which after tightening of the screw coupling likewise forms a small convex excess. Removal of the ring without damage is accomplished by application of pressure by means of a smaller additional groove and a pressure feeding bore discharging into the additional groove.

Abstract: A material for sealing threaded pipe joints includes a multifilament yarn ready-coated with a joint sealing composition. The material is packaged in a dispenser from which the coated yarn may be supplied for direct application to a threaded area of a pipe.

Abstract: A seal arrangement for providing a seal between a nuclear reactor in-core instrument housing and an instrument contained within the housing includes a lower seal assembly surrounding an outer portion of the in-core instrument housing, an upper seal assembly surrounding an outer portion of the in-core instrument, a seal housing enclosing the lower and upper seal assemblies, and lower and upper compression assemblies positioned on respective ends of the seal housing. The compression assemblies each include a drive nut and a compression collar. The compression collars engage and apply an axial load on the seal assemblies to maintain a reliable seal between the seal housing and the outer portion of the in-core instrument housing, and between the seal housing and the outer portion of the in-core instrument.

Abstract: A gasket for a pipe joint includes an annular gasket body which is symmetrical around an axial centerline and is therefore insensitive to axial orientation. The gasket is formed of a resilient material and includes a base adapted to sealingly engage an annular groove formed in one of the pipe segments to be joined. First and second protrusions run along the length of the gasket body and extend radially therefrom. The first and second projections are spaced apart symmetrically about the centerline. An annular bore, bisected by the center line, extends within the interior of the gasket body, and comprises a central region bridging first and second transversely spaced apart lobes. It is particularly suited for sealing an annular space in a bell-and-spigot pipe joint and provides an increased surface contact area to compensate for defects in the sealing surfaces of the pipes.

Abstract: The present invention discloses multiple sealing systems for composite risers and methods of preventing interior fluid leakage to the outside of composite risers. Single or multiple elastomeric seals are formed between an elastomer applied in single or multiple grooves provided circumferentially along the outer surface of a metal to composite interface (MCI) of a liner assembly of the composite riser and an elastomeric shear ply provided on the outside of the liner assembly. The elastomeric seals and a seal between the MCI and the liner of the liner assembly provide a multiple sealing system for the composite riser to prevent leakage of interior fluids. In the event that the integrity of the seal between the MCI and liner fails or the integrity of the liner is compromised, the elastomeric seals would prevent leakage of the fluid to the outside of the composite riser.

Abstract: The ring seal and retainer assembly includes an annularly shaped ring seal defining a radial inner surface, a radial outer surface, first and second axial end surfaces and a central bore for fluid or gas passage. A retainer is provided for affixing and positioning a ring seal in a sealing assembly. The retainer includes a circular sidewall sized and positioned to engage and cover the ring seal's radial outer surface. The retainer further includes a means for affixing the circular sidewall to the ring seal. In a first embodiment, the retainer includes an inwardly projecting ridge for projecting into a groove formed on the ring seal's radial outer surface. In an additional embodiment, the retainer includes a plurality of ridge segments which project into the ring seal's groove. In still an additional embodiment, the circular sidewall includes upper and lower inwardly projecting edges forming a “C” shaped cross-section.

Abstract: A connection for threaded pipes and other tubular sections including a gasket for interposition between a first and an opposing second interface surface of the connection. The gasket includes a retainer and a generally annular seal element received in a groove formed into at least one side of the retainer. Such retainer side further is formed as having one or more channels extending extend radially through the groove and the inner or outer perimeter of the retainer. Each such channel defines a vent for relieving hydrostatic fluid pressure as the gasket is compressed between the interface surfaces.

Abstract: The improved ring seal includes an annularly shaped body element having a radial inner surface, a radial outer surface, a first axial end surface and a second axial end surface. The ring seal also includes a plurality of bores which project radially inward from the radial outer surface toward the radial inner surface. The projection of the bores through the ring seal form sidewalls which project between the axial end surfaces and radially from the ring seal's radial outer surface towards the ring seal's radial inner surface. The addition of the bores to the ring seal increases the ring seal's deformation during sealing compression, while the sidewalls provide elastic recovery of the ring seal during repeated cycles of compression and decompression. The ring seal also includes a circular ridge axially projecting from both axial end surfaces. The axial ridges separate the end surfaces into inner axial end surfaces and outer axial end surfaces.

Abstract: An article of manufacture which comprises a material for sealing threaded pipe joints comprising a multifilament yarn ready-coated with a joint sealing composition and packaged in a dispenser from which the coated yarn may be supplied for direct application to a threaded area of a pipe.

Abstract: A reduced area gasket has a sealing ring around the inside perimeter of the gasket. Remaining portions of the gasket are removed or compressed so that the bolt load is focused on the sealing area when the flange is tightened. In this way, the lower bolt loads mandated by plastic piping may be met, and the required sealing may be further obtained.

Abstract: Seal for the static or dynamic sealing of joints, machine parts or other components or structures such as may be found in choke, kill, or other auxiliary line strings for marine oil or gas well risers, hydraulic or pneumatic cylinders or other actuators. The seal may have a U-cup or solid geometry profile including a secondary sealing lip on both the inner and outer diameter thereof which functions as a wiper for the exclusion of outside contaminants, such as seawater, from joint sealed.

Abstract: A waterstop ring provides a flexible joint connection between a pipe and a concrete structure. The waterstop ring includes an annular waterstop member projecting from an outer circumference thereof, and a pair of annular shoulder portions respectively disposed on each side of the waterstop member. The waterstop member and each of the shoulder portions each include hollow annular cavities defined therein, such that when the waterstop ring is installed in a connection between a concrete structure and a pipe, and partially embedded within the concrete structure, the annular cavities allow deformation of the waterstop ring and thereby allow tilting movement of the pipe in a direction away from the central axis of the pipe.

Abstract: Provided is a sealing unit for sliding onto a water outlet (38) with formation of a fluid-tight connection with a water hose or similar that is equipped with said sealing unit (1), and that comprises at least one outer sealing ring (3) consisting of an elastic material and having an annular base body (4), from the area (5) of which that is oriented towards the center, a circumferential outer sealing collar (6) extends towards the center, which collar is moreover inclined in the insertion direction (17) and encloses an opening (16) through which the water outlet (38) can be inserted, and a sliding funnel (8) comprising an annular circumferential base body (9) resting upon the exterior of the base body (4) of the sealing ring (3), and from which several lobe-type tongues (11) articulated to the base body (9) by means of their bases (10), extend radially inwards, which tongues rest upon the exterior of the outer sealing collar (6) and form a kind of funnel together, and the free ends of which enclose the opening

Abstract: A deck post (or brace) having a non-circular cross-section is secured to a roof deck. A lead pipe jack (sleeve) is slid over the post. A waterproofing assembly having a collar and a skirt is provided; the collar has an opening with generally the same non-circular cross-section as that of the post. The collar opening is positioned on the deck post, and the unit is slid down the post until the collar is at the top of the sleeve, the skirt extending down over the sleeve. A clamp is then positioned and tightened around the collar to provide a watertight seal on the deck post. When the post is already installed on a roof deck and the sleeve and the waterproofing assembly cannot be slid into place on the post, a modified retrofit waterproofing assembly and sleeve are used to provide the waterproofing. The modified sleeve is a split lead flashing jack with an open seam on one side. The sleeve is opened up, wrapped around the post and soldered closed.

Abstract: A compartment seal is disposed about an automotive tube or hose at the automotive firewall to prevent leakage of smoke and fumes generally from an engine compartment to an occupant compartment. The compartment seal comprises a rigid washer body member having a plurality of apertures circumferentially arranged around an opening therethrough,. The plurality of apertures is receptive to fasteners for attachment of the body member to the automotive firewall to provide a seal between the engine compartment and the occupant compartment. The tube or hose is attached to fittings at either end and passes through the opening in the body member. The body member includes a seal component within the opening configured to form a seal between a periphery of the hose and the seal component. The seal component is disposed within the opening of the body member.

Abstract: A seal fitting for use in high pressure equipment for allowing instrumentation wires to exit from the interior to the exterior of the equipment includes a main body which is welded to an opening in the equipment. A seat member is positioned within the main body such that two wires are passed through each of the slots in the seat member. The seat member is fixed to the main body by a pin that passes through the main body and into a portion of the seat member. A follower member, keyed to the seat member so that slots in the follower member align with the corresponding slots in the seat member, is then placed within the main body. The follower member is fixed to the seat member by a screw that passes through a central hole in the follower member and into a central portion of the seat member. Brazing alloy is then applied around the cap screw, on top of the follower member and around the wires exiting through the slots in the follower member.

Abstract: A sealing device equipped with a lip made of a rubber material composition wherein the rubber material composition comprises 100 parts by weight of a tetrafluoroethylene-propylene copolymer and 0.02 to 10 parts by weight of an ethylene-propylene-based copolymer is described, by which a long life sealing device that is not deteriorated even when used under an environment where chemicals such as a cutting lubricant containing an additive adversely affecting rubbers contact the sealing device is provided.

Abstract: A gasket that seals a lead opening on an electric motor has opposite first and second surfaces and a lead opening passing through the gasket. The gasket has a wall projecting outwardly from the gasket first surface and extending around the gasket lead opening, defining a cavity adjacent the gasket lead opening. The gasket is positioned on the electric motor so that the gasket lead opening is aligned with an electric motor lead opening and motor leads pass through the gasket lead opening. A conduit box having a bottom wall with a lead opening is positioned on the electric motor with the gasket between the conduit box and the electric motor, the conduit box lead opening aligned with the gasket lead opening and the motor leads passing through the conduit box lead opening. A sealant is applied in the gasket cavity, and seals the gasket lead opening closed. The gasket wall prevents the sealant from contacting and adhering to the conduit box.

Abstract: A seal apparatus including an elongated body formed of a resilient expandable material defining an interior chamber and having a longitudinal axis. The elongated body is capable of being rolled up on itself by rolling one of the first and second ends of the elongated body in a direction parallel to the longitudinal axis. At least one stem is attached to the elongated body and is in fluid communication with the interior chamber.

Abstract: The present invention discloses redundant sealing systems for composite risers having metal liner assemblies and methods of preventing interior fluid leakage to the outside of composite risers. An elastomeric seal is formed between an elastomeric tip provided on the end of a metal to composite interface (MCI) of the liner assembly and an elastomeric shear ply provided over the liner assembly. The elastomeric seal and a mechanical seal between the MCI and a transition ring which secures the liner to the MCI, provides a dual sealing system for the composite riser to prevent leakage of interior fluids. In the event that the integrity of the mechanical seal or the integrity of the liner is compromised, the elastomeric seal would prevent leakage of the fluid to the outside of the composite riser.

Abstract: A sealing member for sealing a joint between a pipe and a wall defining an opening is provided. The sealing member has an annular base, a projection, and preferably first and second annular flanges. The annular base has a bottom and first and second sidewalls. The projection is attached to the base for anchoring the sealing member within the wall. In some embodiments it extends radially outwardly from the base. The first and second annular flanges extend from opposite sidewalls of the base. The first and second flanges each have a top and a bottom surface. The top surfaces of each can have an annular depressed portion, and each of the bottom surfaces can have a plurality of grooves formed therein. Preferably, the base includes at least one cavity extending completely around the circumference of the sealing member.

Abstract: A flat conductor made in the form of a tubular conductor is sealed at an end connection using a rigid core of convex external surface. The rigid core is slipped into an end part of the tubular flat conductor. A protective sleeve made of a cold-recoverable material seals the conductor in compression between the core and the sleeve.

Abstract: A seal for sealing the space between a cable and the ends of the corrugated conduit. The seal includes a seal body including a base portion, an engagement portion attached to the base portion and being insertable in the space between the cable and the conduit, and a retainer disposed on the engagement portion for engaging at least one of the corrugations of the conduit. The base portion preferably has a groove for retaining an O-ring such that the O-ring tightly circumscribes the cable to create a seal. The retainer preferably includes helical threads disposed on the outside surface of the engagement portion. Alternatively, however, the retainer can include a rib which engages a corrugation or one or more protrusions which engages a corrugation. Further, the seal body is preferably split into two halves so that it can be installed onto the cable without requiring access to the end of the cable. In addition, the seal body may include two halves interconnected by a hinge so that it is one-piece.

Abstract: The object of this invention is to provide a structure of seal ring, and seal structure using the seal ring for flange joints of composite tanks and pipes, that prevents seal surface variations due to differences in thermal contraction between the seal ring and the tank/the flange joint, etc., that improves the resilience of the seal, and that prevents gas leakage due to poor sealing, in order to achieve the stable sealing. The seal ring fits into a ring groove formed in a sealed unit such as a tank unit or a flange joint to provide a tight seal to contain fluids. The heart-shaped seal ring has three curved surface areas that smoothly flow together, comprised of a first curved seal surface which contacts the formed surface of the ring groove, a second curved seal surface which contacts the seal surface of a second member (e.g. manhole cover), and a projecting curved surface on the opposite side.

Abstract: A sealing arrangement (14) has a housing gap, to be sealed, between two components (15, 16) and a seal (1) which consists of two interconnected sealing components (2, 3), a first extrusion-resistant, deformable sealing component (2) and a second more deformable sealing component (3). The first sealing component (2) has an abutment surface (6) facing the sealing surface (17) of the component (15), and a contact surface (9) for abutment on the other component (16). The second sealing component (3) abuts the first sealing component (2) and has an edge (4) projecting past the abutment surface (6). The first sealing component (2) can be pressed onto the sealing surfaces (17; 18) of the components (15, 16; 30, 31) to close the housing gap in response to system pressure. The second sealing component (3) can be sealingly pressed onto the sealing surfaces (17, 18). The sealing arrangement (14) is of simple construction and can produce an effective high pressure seal in Common Rail injectors or similar systems.

Abstract: A seal for a radially expansible conduit connection is disclosed. The seal includes a first sealing surface disposed proximal to an end of a male portion of the connection and a corresponding second sealing surface disposed proximal to an end of a female portion of the connection. The first and said second sealing surfaces are substantially opposite each other upon connection of the male and female portions. The seal includes a first clearance surface proximal to the first sealing surface and a second clearance surface proximal to the second sealing surface. The first and second clearance surfaces are substantially opposite each other upon connection of the male and female portions.

Abstract: A fluid seal for sealing a joint between two components in a fluid line has an integral filter. The seal has sealing portions on each side of the filter that are compressed by relative axial movement of the components to effect a fluid-tight seal therebetween with the filter extending across the fluid line. The seal and filter are located in a central hole of a support plate with the seal bonded to the marginal edge of the hole.

Abstract: A method of, and apparatus for, closing an opening defined at least in part by a wall which at least partially surrounds the opening. The wall has a first thickness. According to one embodiment, a strip of material includes a groove which opens in a first direction and resilient projections which extend in a second, generally opposite direction from the first direction. The method according to this embodiment includes receiving the edge of the surrounding wall in the groove. The projections project at least partway across the opening substantially to obstruct access to it. In another embodiment, a method of closing an opening defined at least in part by a wall of a cover for a valve of a fuel tank includes providing a device having a perimetrally outwardly opening groove. The device further includes resilient projections which extend generally in an opposite direction to the direction in which an adjacent region of the groove opens. The groove receives the edge of the surrounding wall.

Abstract: A rubber laminated bearing-seal, consisting of multiple flat or curved alternate laminations of metal and rubber bonded together and having an aperture, is seated in an apertured receptacle in the wall of a pressure vessel and supports a shaft that penetrates the apertures, extending from one side of the wall through to the other side. Shear strains in the rubber laminations permit the shaft to carry limited movements through the wall while the laminations seal against any flow of the liquid or gaseous medium on one side toward the other side and withstand the resulting thrust caused by large pressure differences. The torque reaction of this bearing-seal is essentially proportional to rotation angle. A potential use is in the intense hydrostatic pressure environment of undersea applications at great depths, carrying limited motion through the hull of a submersible craft.

Abstract: Gasket for sealing between flanges in a pressurized fluid system. A central opening is disposed within an inner periphery of the gasket, the inner periphery being curved toward the central opening. Fluid pressure on the inner periphery is reacted by hoop tension in the gasket. The outer periphery of the gasket has concave segments between fastener holes so the area of the gasket is substantially less than the area of the flanges. In this manner, the clamping pressure exerted by the flanges on the gasket is increased.

Abstract: The sealing device for a control member (17) is provided with a shaft (16) passing through a sealed casing and comprising a tube (1) driven into a bore (3) of the casing (4). A shaft (16) of the control member (17) is engaged in the tube (1) and at least one joint (18, 19) ensures normal sealing between this tube and this shaft. It comprises a compression key (6) screwed on the tube (1) comprising an upper portion (8) overlying the tube (1) and surrounding the shaft (16) of the control member (17). A compression joint (15) is disposed in the space comprised between the upper portion (8) of the compression key, the tube (1) and the shaft (16).

Abstract: A spiral-wound gasket includes a plurality of tightly wound metal windings to form a core. The windings each have a Chervon cross-section, wherein V-notched undulations of each winding registers with an adjacent winding at said notches. The edges of the windings are welded to form a pre-assembled integral composite that is installed into a J-shaped outer wrap or cover. Finally, the cover is closed about the core so as to entirely cover and encapsulate the core. In a preferred form, both the core and outer cover are formed of stainless steel materials.

Abstract: A back-up ring is disclosed wherein the ring is a knitted mesh section substantially surrounded by an outer coating covering substantially all of the knitted wire mesh section, the coating having contact with the outer and inner surface of an annulus.

Abstract: For manufacturing a seal between two machine parts (10, 11) which together enclose a space (14) in which, at least at times, high pressure and/or high temperature prevail, sealing means which contain a curable composition (30) are arranged between the two machine parts (10, 11). The curable composition (30) is applied directly onto one or both machine parts (10, 11) in liquid form at least in the area which does not directly adjoin the space (14) in which, at least at times, high temperature and/or high pressure prevails. The two machine parts are built in before the curing of composition (30). A sealing ring can be inserted between the two machine parts (10, 11) directly around the edge of the high pressure and high temperature space (14) or that edge can be slightly raised and the curable composition (30) can be used for sealing outside this area.

Abstract: The present invention relates to a single-piece air induction sealing system. A fuel injector bore is included in the air induction sealing system. The air induction sealing system can be inserted into a manifold runner.

Abstract: An article of manufacture which comprises a material for sealing threaded pipe joints comprising a multifilament yarn ready-coated with a joint sealing composition and packaged in a dispenser from which the coated yarn may be supplied for direct application to a threaded area of a pipe.

Abstract: A modular fluid storage tank, intended for underground storage of water, utilizing alternating circular and octagonal ribs in the main body and curved, ribbed, end caps. Interconnection of the tanks uses rigid pipe or semi-flexible hose. The coupling between the pipe and the tank incorporates a fitting, integrally molded into the tank, which extends into the interior of the tank, and a flexible sleeve which fits over, and is clamped to, the fitting and the pipe. The coupling is protected from the environment and is accessible from within the tank after installation for inspection and repair without the need to excavate the tank. The tank preferably has approximately equal length and diameter for improved strength. It is relatively small and lightweight, suitable for transport to and installation at a remote location without heavy equipment.

Abstract: The inventive sealing body (DK) is comprised of a number of segments (DS1, DS2, DS3) in whose sealing chambers (DKAA, DKAM) a sealing block (DBAS, DBMS) is arranged that is made of an easily deformable, in particular, gel-like substance. Tabs (ZE) which conically extend toward one another serve to center the cable which is inserted into the sealing body (DK) and held therein. Wedges (K) which can be actuated from the outside act upon assigned pressure elements (DE), which deform the corresponding sealing block (DBAS, DBMS) thus displacing the gel-like substance in a radial direction.

Abstract: The invention relates to a seal for medium-conducting components, whereby the components (12, 13) comprise sealing surfaces (20, 25), which are exactly complementary to each other and which are directly pressed together to form a gap-free seal. The contact surfaces (44) between the sealing surfaces is limited to a narrow region directly adjacent to the medium cavity (19). Said gap-free and dead-volume-free seal can be used, for example in germfree, or sterile processes.