Described herein are methods and system for welding, for example, girders. The method may include activating a homopolar generator. The method may include applying a force to two metal girders at a desired coupling joint. The method may include generating an electrical pulse using the homopolar generator and conducting the electrical pulse to the desired coupling joint to increase a temperature of the girders. The method may include forming a weld at the desired coupling joint attaching the two metal girders at the desired coupling joint. In some embodiments, the homopolar generator may include a radial bearing rotor including a rotatable shaft and a bearing assembly. The bearing assembly may include nonmagnetic bearings. The homopolar generator may include a field coil. The homopolar generator may include a brush actuation mechanism which when activated engages a plurality of brush devices to the radial bearing rotor.

A method for forming a high temperature field joint between two insulated pipe sections, and an insulated conduit having a low temperature field joint. The conduit comprises a steel pipe with a corrosion protection coating and a pipe insulation layer comprising a polymer composition having thermal conductivity of less than about 0.40 W/mk, and/or heat resistance to continuous operating temperatures from about 150° C. to above about 205° C. After a circumferential weld joint is formed between the two pipes, a first field joint insulation layer is applied over the joint area, the first field joint insulation layer comprises a polymer composition having heat resistance to continuous operating temperatures from about 150° C. to above about 205° C.

An assembly includes at least one member having first and second ends. A dual metal adapter for connecting to the at least one member includes an inner tube for receiving and contacting the first end of the at least one member and being formed from a first metal having a first resistivity. An outer tube extends over the inner tube and is secured thereto. The outer tube is formed from a second metal having a second resistivity greater than the first resistivity. The first end of the at least one member is metallurgically bonded to the inner tube.

A method for producing a steel underwater pipe for carrying a corrosive fluid, includes the successive steps: applying a layer of corrosion-resistant steel alloy on a terminal part of the internal wall of each pipe element from its end to be welded; the application of a plastic coating, on the internal wall of each pipe element; covering only a first part of the layer of metal alloy, a terminal part of the layer of metal ally on the side of the end to be welded of each pipe element not being covered by the plastic coating; the coaxial insertion and the crimping of a compression ring against the terminal part of the plastic coating; and the assembly by welding directly together the ends of two pipe elements by a corrosion-resistant steel alloy weld.

An axle suspension system and a method of manufacture. The axle suspension system may have an axle, an axle wrap, and a weld seam. The axle wrap may have first and second wrap portions that mechanically interlock with each other and that have overlapping ends that may receive a weld seam.

An apparatus and method for reinforcing a welded-lap pipe joint includes a first pipe segment having a bell-end presenting a receptacle, a spigot-end of a second pipe segment extending into and welded to the bell-end receptacle to form a welded-lap joint, and a bell-shaped reinforcing sleeve surrounding the welded-lap joint. In exemplary embodiments the reinforcing sleeve is welded to the first or second pipe segments. Also disclosed are a method of assembling a reinforced welded-lap pipe joint.

A galvanized reinforcement beam is continuously formed by uncoiling a roll of galvanized sheet stock in a generally horizontal plane. Protrusions are formed at an upper surface of the sheet stock, which is then roll formed to form a tubular shape with the protrusions abutting a surface of the sheet stock to form venting gaps. The sheet stock is laser welded at the protrusions to continuously form a weld joint, where zinc oxide gas generated from the welding is permitted to escape an interior of the tubular shape through the venting gaps.

A method for producing a retort for a nitriding furnace, in which metallic workpieces are heat-treated in a pre-determined atmosphere, includes pickling at least the surfaces of the retort, which are configured to come into contact with the pre-determined atmosphere while the nitriding furnace is operating, by using a pickling agent. The pickled surfaces may then be electropolished and passivated. A retort may be produced according to this method and the retort may be used in a nitriding furnace.

A double-walled tube section for constructing a double-walled tube segment suitable for underpressure applications such as an evacuated tube transport system.

A mechanical part configured to be placed under torque. The mechanical part includes an inner tube having, a corrugated web, and an outer shell. The inner tube has an outer tube circumference, a tube axial direction, and a tube length. The corrugated web has a plurality of peaks and a plurality of troughs, a height measured as a difference between one of the peaks and one of the troughs, and a web length perpendicular to the height and in the tube axial direction. The outer shell has an inner shell circumference, an outer shell circumference, and a shell length. The plurality of troughs is affixed to the outer circumference of the inner tube. The plurality of peaks is affixed to the inner shell circumference of the outer shell. The web length is aligned with the tube length and the shell length.