Abstract: A first tubular, inner radial annular seam is produced to weld together two hollow cylinders by narrow-gap tungsten inert gas arc welding. Narrow-gap metal gas-shielded arc welding is used to create another tubular, outer radial annular seam to further weld together both hollow cylinders. In this manner, the rotational axis of the rotor shaft remains vertically aligned throughout the entire production method of welding together the shaft parts. In this manner, the required production time can be advantageously reduced and the use of welding filler can be effectively decreased.

Abstract: An apparatus for improved narrow-gap welding is provided. The apparatus includes an inert gas tube within which a contact tube is arranged, the contact tube includes a wire feed for a melting wire. The end of the inert gas tube is ceramic. In another embodiment, the inert gas tube of the apparatus includes a plurality of materials with a high thermal conductivity. A first metallic material at the end of the inert gas tube has a higher thermal conductivity than a second material at a start of the inert gas tube. The first metallic material is molybdenum, tungsten, an alloy of molybdenum or tungsten, or copper or a copper alloy.

Abstract: A first tubular, inner radial annular seam is produced to weld together two hollow cylinders by narrow-gap tungsten inert gas arc welding. Narrow-gap metal gas-shielded arc welding is used to create another tubular, outer radial annular seam to further weld together both hollow cylinders. In this manner, the rotational axis of the rotor shaft remains vertically aligned throughout the entire production method of welding together the shaft parts. In this manner, the required production time can be advantageously reduced and the use of welding filler can be effectively decreased.

Abstract: A method of testing a fusion weld for a shaft includes producing two shaft subsections, wherein the shaft subsections are symmetrical and faun a cylinder coaxially along the axis of rotation. Core regions of each shaft subsection are removed in order to produce open recesses in the cylinder within remaining tubular webs. The two shaft subsections are positioned coaxially one on top of the other, wherein the two remaining webs are mutually adjacent and the two open recesses form a hollow space. A first tubular ring seam is produced by narrow-gap arc welding and in one of the two shaft subsections a passage from outside into the hollow space is produced. Further, a quality of the first tubular ring seam within the hollow space during and/or after the welding operation is evaluated by a detection device or radiation source which is introduced through the passage into the hollow space.

Abstract: An apparatus for narrow-gap welding is provided. The apparatus includes an inert gas tube and a contact tube which is arranged in the inert gas tube. The contact tube includes a wire feed for a melting wire. The contact tube has an end with an end face and a longitudinal axis, wherein the longitudinal axis forms an angle other than 90° with the end face of the end. In a further embodiment, the contact tube has a contact nozzle at the end and a jacket surface, wherein one end of the contact nozzle does not project beyond an imaginary extension of the jacket surface in the longitudinal direction of the contact tube.

Abstract: An apparatus for improved narrow-gap welding is provided. The apparatus includes an inert gas tube within which a contact tube is arranged, the contact tube includes a wire feed for a melting wire. The end of the inert gas tube is ceramic. In another embodiment, the inert gas tube of the apparatus includes a plurality of materials with a high thermal conductivity. A first metallic material at the end of the inert gas tube has a higher thermal conductivity than a second material at a start of the inert gas tube. The first metallic material is molybdenum, tungsten, an alloy of molybdenum or tungsten, or copper or a copper alloy.

Abstract: An apparatus for improved narrow-gap welding is provided. The apparatus includes an inert gas tube within which a contact tube is arranged, the contact tube includes a wire feed for a melting wire. The contact tube is coolable in the interior. In another embodiment, the apparatus is formed from an inner core and an outer jacket wherein at the end of the contact tube, the contact tube has a ceramic coating. The coating is applied to the outer jacket and/or the inner core.

Abstract: An apparatus for improved narrow-gap welding is provided. The apparatus includes an inert gas tube within which a contact tube is arranged, the contact tube includes a wire feed for a melting wire. In one embodiment, the inert gas tube includes a plurality of cooling tubes in order to provide active cooling. In another embodiment, the inert gas tube is rectangular.

Abstract: There is described a method for submerged-arc narrow-gap welding, in which the wire electrode is set in oscillating motion in the gap in order to produce a first bead, the arc moving backwards and forwards between one of the workpiece edges and a middle section of the gap so that the first bead does not extend from the first to the second workpiece edge.

Abstract: In one aspect, a method for depositing a metallic substrate on a wall of a narrow depression of a metallic component is provided. A wire electrode is introduced into the depression and thereby bent in the direction of the wall by means of a guide. A suitable voltage is applied to the component and to the wire electrode in order to create an arc, which melts the wire electrode in certain regions. The molten material of the wire electrode is thereby deposited on the wall of the component. The wire electrode is progressively fed in during the depositing operation.

Abstract: The switching contact is suitable for electrical switching devices. A contact element is connected to a contact support. In order to connect relatively large contact elements to the contact support with sufficient connection quality, in particular by means of cost-effective resistance welding or laser welding, the contact element is formed from a number of contact element segments and the individual contact element segments are assembled to make up the contact element. Different switching properties can be set by using contact element segments of the same or different material compositions and/or geometries.

Abstract: A thermally conductive, electrically insulating connection, which is not sensitive to air moisture comprises a ceramic layer formed by thermal spraying on a surface of the workpiece, which layer is either impregnated or sealed with electrically insulating material and is joined to another workpiece which may be a ceramic layer which has been either impregnated or sealed and attached to another member. The connection is particularly useful in power assemblies with at least one power component for conducting away lost heat from the component with a sufficient electrical insulation of the component from the cooling body or heat sink.

Abstract: In a known process, oxide powders derived from the four-component systems yttrium-barium-copper-oxygen or lanthanum-strontium-copper-oxygen are mixed, pressed, sintered, ground and then heat-treated to produce a superconducting material which can be shaped to the desired cross-section. According to the invention, the powder is compacted by isostatic pressing and the blank so obtained is extruded at a temperature.gtoreq.500.degree. C. to form a metallic sheath with a deformation ratio of at least 50%. The extruded blank is then converted to wire or strip. The current-carrying capacity of the high-temperature superconductor is improved by the extrusion and the resulting alignment of the crystallites. The process can be implemented using known high-temperatures superconducting material.