The present invention relates to a method for welding a half coil of a reactor, which performs the gas metal arc welding (GMAW) along a half coil temporarily welded to a welding machine body using an automatic welding machine to increase a formation amount of back beads, thereby increasing coupling strength of the half coil, increasing airtightness of a fluid flowing along the half coil, securing uniform welding quality by automatic welding, increasing productivity, and reducing production costs.

The present invention relates to a method for welding a half coil of a reactor, which performs the gas metal arc welding (GMAW) along a half coil temporarily welded to a welding machine body using an automatic welding machine to increase a formation amount of back beads, thereby increasing coupling strength of the half coil, increasing airtightness of a fluid flowing along the half coil, securing uniform welding quality by automatic welding, increasing productivity, and reducing production costs.

The present invention relates to a pre-stressed steel sheet and a method a method of manufacturing the same.

An embodiment of the present invention provides a pre-stressed steel sheet comprising: a base material; and a plurality of weld lines formed on the base materials, wherein the average spacing between each pair of the weld lines is equal to or greater than five times the width of the weld lines and equal to or less than half the width of the steel sheet.

According to an aspect of the present invention, a pre-stressed steel sheet having improved bendability can be provided, and accordingly when the pre-stressed steel sheet is applied to a structural member such as a girder or beam, the bendability of a structure can be improved.

Systems, methods, and apparatus to preheat welding wire are disclosed. An example welding assembly for a welding torch includes: a first contact tip configured to conduct welding current to a consumable electrode; a second contact tip configured to conduct preheating current to the consumable electrode; and a cooling body configured to transfer heat from at least the first contact tip to coolant and to conduct the welding current.

Systems, methods, and apparatus to preheat welding wire are disclosed. An example welding assembly for a welding torch includes: a first contact tip configured to conduct welding current to a consumable electrode; a second contact tip configured to conduct preheating current to the consumable electrode; and a cooling body configured to transfer heat from at least the first contact tip to coolant and to conduct the welding current.

A welding structure of a press-formed part made by combining and joining two parts formed by press-forming and each having an opening portion on at least one side of a cross-section, while the opening portions face each other, and includes a step portion that is provided by forming a bent projection projecting outwardly on a tip end portion of a side wall portion of a lower side part, partially or entirely on a joining surface. A tip end side of the step portion is fitted into the opening portion of an upper side part, and the step portion of the lower side part and the tip end of a side wall portion of the upper side part are linearly joined by arc welding.

In a method for defining welding parameters for a welding process on a workpiece, a welding torch fastened to a robot is guided over the workpiece along a predetermined welding path and predetermined welding parameters for processing the workpiece are set as a function of the position along the welding path. A welding device carries out a welding process. For the more exact definition of the welding parameters, before the welding process is carried out, at least one parameter representing the cooling is recorded as a function of the position along the welding path, and the at least one parameter representing the cooling along the welding path is considered for the welding process when defining optimized welding parameters as a function of the position along the welding path.

In a method for defining welding parameters for a welding process on a workpiece, a welding torch fastened to a robot is guided over the workpiece along a predetermined welding path and predetermined welding parameters for processing the workpiece are set as a function of the position along the welding path. A welding device carries out a welding process. For the more exact definition of the welding parameters, before the welding process is carried out, at least one parameter representing the cooling is recorded as a function of the position along the welding path, and the at least one parameter representing the cooling along the welding path is considered for the welding process when defining optimized welding parameters as a function of the position along the welding path.

A cracked gas cooling heat exchanger includes a tube connection between an uncooled tube (1) and a cooled tube (2), having a cooled inner tube (3) enclosed by a jacket tube (4), with a tube intermediate space (5) for flowing cooling medium. A gas inlet header (11) has a GI tube inner part (12) and a GI tube outer part (13) and a cooling space (14) with an insulating layer (15). The GI tube outer part connects via a water chamber (6) to the jacket tube. The GI tube inner part faces the inner tube and is connected on a face (8) of the water chamber. A weld backing ring (16), between an end face (9) of the cooling space and a bottom face (8) of the water chamber, is in the insulating layer of the cooling space, arranged in a turn-out/groove (17) in the insulating layer.

A method for joining by welding or gluing joining elements to components, with the following steps: preparation of a joining element, which comprises a first joining surface, and preparation of a component, which comprises a second joining surface; preparation of the first or second joining surface; and carrying out the joining process, in which the joining element is joined to the component; wherein the preparatory step comprises at least one of the following cleaning methods for cleaning the first or second joining surface: a TIG arc method, a plasma gas cleaning method, and a snow jet method.