Abstract: A coupling arrangement has a coupling body and a helically shaped undulated metal pipe which has an end face extending along a screw thread of its undulation. A metal holding ring is mounted on the connecting part resting against the latter, where the outer diameter of the holding ring corresponds approximately to the outer diameter of the pipe, where the end face of the holding ring facing the pipe extends along a screw thread corresponding to the screw thread of the pipe, and where the holding ring is connected in the mounted position, fixedly to the connecting part by resting fixedly and tightly against the end face of the pipe.

Abstract: A pipe for underwater transportation of fluid is indicated which includes a pressure-tight metal inner pipe for conducting the fluid, wherein for its stabilization in radial direction at least one profiled metal strand and for stabilizing in the axial direction at least one tension-proof strand are wound around the inner pipe. The inner pipe (1) is a metal pipe which is undulated transversely of its longitudinal direction and which for stabilization in the radial direction is surrounded by at least one first radial reinforcement (3) which is composed of a profiled helically extending profile strip whose windings are placed closely next to each other or engage each other and are hooked together. Arranged around the first radial reinforcement (3) is arranged a metal pipe undulated transversely of its longitudinal direction as the outer pipe (5); at least two layers of tension-proof strands (7, 8) are wound around the outer pipe (5), preferably with oppositely directed pitch.

Abstract: A termination for a superconductive cable (1) is provided, consisting of a pressure-tight metal inner container (2) in which there is a liquid refrigerant and into which the cable protrudes, and a metal outer container (3) which is separated from the inner container by an intermediate space (4) in which vacuum insulation is applied. A first rupture diaphragm (6) is applied in the wall of the inner container (2) and a second rupture diaphragm (7) is applied in the wall of the outer container (3) level with the first rupture diaphragm (6). An evacuated relief space (8), which contains superinsulation and is sealed from the intermediate space (4) with the vacuum insulation by a pressure-tight wall (9), is provided between the two rupture diaphragms (6, 7).

Abstract: A pipeline for the transport of a pressurized flowable medium, consisting of a metal tube corrugated transversely to its longitudinal direction and of a hose which is arranged in the same and consists of plastic. In the position of use the hose bears against the inwardly pointing wave troughs of the metal tube, which hose has a multiplicity of holes separated from one another in the wall of the same over its entire axial length. The wave troughs of the metal tube penetrate slightly into the surface of the hose so as to fix the latter with respect to axial loads.

Abstract: A modular design of a fault current limiter includes one ore more current limiting units 1 with one or more superconducting elements 2 and where standarisized current limiting units 1 and standardized modular insulation housings 10 can be used for modular design of a fault current limiter.

Abstract: A flexible conduit pipe for transporting fluids is specified, which consists of two corrugated metallic tubes, an inner tube (1) and an outer tube (2), which are arranged concentrically to one another and are separated from one another by an encircling annular space in which a spacing means is arranged. The spacing means consists of a plurality of rings (4,5) which bear with a basic body (6) against inner tube (1) and outer tube (2) and are arranged at an axial distance from one another in the annular space (3). The rings (4,5) have on their inner circumferential surface a rib (7) which extends in the circumferential direction, corresponds to the corrugation of the inner tube (1) and engages in a respective corrugation trough of the inner tube (1).

Abstract: A line pipe for the transport of deep-frozen media, consisting of at least two corrugated metal pipes (2, 4) arranged concentrically and at a distance from one another, an insulation layer (3) being arranged in the annular gap between the two metal pipes (2, 4), the annular gap being evacuated, and a closing valve (10) provided in the outer metal pipe (4) being connectable to a vacuum pump, the closing valve being welded, vacuum-tight, into a smooth-walled metal pipe (9) welded, vacuum-tight, to the exterior of the metal pipes (4). The valve body (10) of the closing valve projects into the interior of the smooth-walled metal pipe (9) and is flush with the outer surface area of the smooth-walled metal pipe (9).

Abstract: An arrangement for monitoring the leak-tightness of an evacuated space which is hermetically closed, leak-tight, by means of at least one metallic wall is specified. A device which is connected to the evacuated space indicates an inadmissible pressure rise in the evacuated space caused by a leak in the wall. The device includes a metallic bellows, which is hermetically connected, leak-tight, to the evacuated space, and an electrical proximity switch to which an evaluation unit is connected. The proximity switch (7) is mounted, in the direction of movement of the bellows (5), at a distance from the end face of the latter, the size of which is varied as a function of the respective axial length of the bellows (5). A tube (9) connected fixedly to the wall (2) is mounted around the bellows (5), so as to maintain an air gap, surrounds the bellows (5) in a moisture-tight manner and is longer than the bellows (5) in its longest initial position corresponding to the expanded state.

Abstract: A termination for a superconductive cable (1) is provided, consisting of a pressure-tight metal inner container (2) in which there is a liquid refrigerant and into which the cable protrudes, and a metal outer container (3) which is separated from the inner container by an intermediate space (4) in which vacuum insulation is applied. A first rupture diaphragm (6) is applied in the wall of the inner container (2) and a second rupture diaphragm (7) is applied in the wall of the outer container (3) level with the first rupture diaphragm (6). An evacuated relief space (8), which contains superinsulation and is sealed from the intermediate space (4) with the vacuum insulation by a pressure-tight wall (9), is provided between the two rupture diaphragms (6, 7).

Abstract: A plug-in coupling for cryogenic lines is described, having at least two pipes (3, 4, 9, 10) fitted one inside the other like a male/female connection while forming an annular gap (16), in which plug-in coupling the pipes (3, 4, 9, 10) are releasably connected to one another by a flange connection (5, 11) located at their “warm” end, the annular gap (16) between the two pipes (4, 9) is sealed at the “cold” end by an annular seal (7) and at the “warm” end by an annular seal (5d) located in the region of the flange connection (5, 11), and the annular gap (16) is connected to a safety valve (13) in the region of the flange connection (5, 11).

Abstract: An arrangement for monitoring the leak-tightness of an evacuated space which is hermetically closed, leak-tight, by means of at least one metallic wall is specified. A device which is connected to the evacuated space indicates an inadmissible pressure rise in the evacuated space caused by a leak in the wall. The device includes a metallic concertina, which is hermetically connected, leak-tight, to the evacuated space, and an electrical proximity switch to which an evaluation unit is connected. The proximity switch (7) is mounted, in the direction of movement of the concertina (5), at a distance from the end face of the latter, the size of which is varied as a function of the respective axial length of the concertina (5). A tube (9) connected fixedly to the wall (2) is mounted around the concertina (5), so as to maintain an air gap, surrounds the concertina (5) in a moisture-tight manner and is longer than the concertina (5) in its longest initial position corresponding to the expanded state.

Abstract: A line pipe for the transport of deep-frozen media, consisting of at least two corrugated metal pipes (2, 4) arranged concentrically and at a distance from one another, an insulation layer (3) being arranged in the annular gap between the two metal pipes (2, 4), the annular gap being evacuated, and a closing valve (10) provided in the outer metal pipe (4) being connectable to a vacuum pump, the closing valve being welded, vacuum-tight, into a smooth-walled metal pipe (9) welded, vacuum-tight, to the exterior of the metal pipes (4). The valve body (10) of the closing valve projects into the interior of the smooth-walled metal pipe (9) and is flush with the outer surface area of the smooth-walled metal pipe (9).

Abstract: A process for the continuous production of longitudinally welded metal tubes where a metal strip (1) is drawn from a strip supply and gradually shaped into a slit tube in a shaping station (2). The slit tube is welded in a welding system (4) along the edges of the strip, and the welded tube (6) is extracted by an extraction device (5). The welding system (4) is a protective gas arc welding system with several electrodes supplied by separate sources (4c, 4d) of welding current. The electrodes are arranged in succession, in the direction of production. The welding system (4) has two welding devices (4a, 4b), whose electrode tips are directed at a common welding point. Only one of the welding devices (4a, 4b) is in operation at any given time, while the other welding device is in a standby position. When an electrode change becomes necessary, the arc of the welding device in the standby position is first struck by means of an auxiliary arc.

Abstract: A method for determining the wall thickness of a metal tube is described. This method has the following features: (a) preparation of a metal tube of a determined length; (b) arrangement of two clamp contacts on the metal tube with an exactly defined distance of separation; (c) connection of the ends of the metal tube with a power source; and (d) measurement of the voltage drop in the metal tube between the clamp contacts.

Abstract: A method for determining the wall thickness of a metal tube is described. This method has the following features: (a) preparation of a metal tube of a determined length; (b) arrangement of two clamp contacts on the metal tube with an exactly defined distance of separation; (c) connection of the ends of the metal tube with a power source; and (d) measurement of the voltage drop in the metal tube between the clamp contacts.

Abstract: A process for the continuous production of longitudinally welded metal tubes where a metal strip (1) is drawn from a strip supply and gradually shaped into a slit tube in a shaping station (2). The slit tube is welded in a welding system (4) along the edges of the strip, and the welded tube (6) is extracted by an extraction device (5). The welding system (4) is a protective gas arc welding system with several electrodes supplied by separate sources (4c, 4d) of welding current. The electrodes are arranged in succession, in the direction of production. The welding system (4) has two welding devices (4a, 4b), whose electrode tips are directed at a common welding point. Only one of the welding devices (4a, 4b) is in operation at any given time, while the other welding device is in a standby position. When an electrode change becomes necessary, the arc of the welding device in the standby position is first struck by means of an auxiliary arc.

Abstract: A method for producing longitudinally welded helically corrugated metal tubing, wherein a metal strip pulled from a strip supply is formed into tubing with a longitudinal slit, the longitudinal slit is sealed by welding and the corrugation is produced by a corrugation tool that is supported eccentrically and at an angle to the tubing axis, is freely rotatable in a rotationally driven corrugator head, and rolls off the surface of the tubing. The metal strip as well as the uncorrugated metal tubing are advanced by a feed device that is provided between the welding point and the corrugation unit. A second feed device (8) engages the corrugated tubing (7) directly behind the corrugation unit (6), and the feed rate of the second feed device is slower than the forward feed rate of the corrugated tubing (7) which results from the pitch of the corrugator disk and the rotational speed of the corrugator head.

Abstract: In a process for continuous production of longitudinally welded metal tubing, in which a metal strip is withdrawn from a strip supply, gradually shaped into a tubing with an open longitudinal slit, and the longitudinal slit is sealed by soldering or welding, a lubricant is introduced into the open slit tubing before sealing.

Abstract: A method for producing an optical cable with a metal tube and at least one optical fiber arranged in the metal tube, wherein optical fiber(s) are inserted into a slotted tube, the longitudinal slot in the slotted tube is welded, and the diameter of the welded tube is reduced. After the reducing operation, the welded tube is gripped by a draw-off device and conveyed in the finishing direction and wound up onto a draw-off disk. Between the draw-off device (10) and the draw-off disk (11), a force which causes elastic elongation of the metal tube (13) in the finishing direction is applied by the draw-off disk (11), and the extent of the elastic elongation is regulated through this force.

Abstract: In a process for continuous production of longitudinally welded metal tubing, in which a metal strip is withdrawn from a strip supply, gradually shaped into a tubing with an open longitudinal slit, and the longitudinal slit is sealed by soldering or welding, a lubricant is introduced into the open slit tubing before sealing.