A welded shaped steel manufacturing device includes: a plate conveying device configured to convey a web member and two flange members in a conveyance direction; and a laser welding device configured to laser-weld butt portions of ends of the web member butting against the two flange members for weld-bonding, wherein the plate conveying device includes a web member holding device having surface side rollers arranged at intervals in the conveyance direction in a position not to block laser irradiation from the laser welding device toward welding points, and wherein the web member is held with the surface side rollers over a predetermined range in the conveyance direction, and wherein side ends of the surface side rollers facing the two flange members are positioned along boundaries of areas having spatters dispersed from the welding points in a degree exceeding a predetermined value.

Embodiments of an automatic seam fitter attachment for use with an automatic welding machine are designed to automate the plate edge cleaning, tight seam fitting, and tacking or welding of metal lapped or butted plates. The seam fitter attachment can be used on any product or in any industry where metal lap or butted plates seam together. The attachment may be provided with a power cleaning brush that cleans the edges of the plates and mechanically forces plate tightness as they are being tacked or welded.

The present invention provides a lap fillet arc welding joint including a first metal sheet, a second metal sheet, and a weld bead. A region of the first metal sheet on one end side is bent. In a cross-sectional view in a cross section perpendicular to a weld line of the weld bead, in a first direction, a position of a tip end of the bent region of the first metal sheet overlaps a region of the second metal sheet on one end side. In a second direction, an amount of deviation between a central axis of a region connected to the bent region of the first metal sheet and a central axis of the region of the second metal sheet on one end side is times or less of the average value of sheet thicknesses of the first metal sheet and the second metal sheet. A joint portion length, which is a length from a root portion of the second metal sheet to a weld toe portion of the first metal sheet, is two times or more of the sheet thickness of the second metal sheet. The position of the weld toe portion of the first metal sheet in the second direction is in a range from a first position to a second position.

The present disclosure relates to electro-conduction devices and methods for submerged arc welding of straight-seam steel pipes and in particular to a lateral electro-conduction device and method for multi-wire submerged arc inner/outer welding of a straight-seam steel pipe. The present disclosure aims to overcome the problem of poor closing of the electromagnetic field resulting from the existing negative-pole electro-conduction mechanism and the problem of unstable welding process resulting from bending deformation in the steel pipe welding process. The device includes: a floating surface contact electro-conduction device, capable of forming a surface contact with an outer surface of the straight-seam steel pipe; a lateral electro-conduction brush device, including multiple electro-conduction brushes and electrically connected with the floating surface contact electro-conduction device; a lateral electro-conduction metal plate, electrically connected with a negative-pole wire harness of a welding machine and electrically connected with the lateral electro-conduction brush device. Therefore, an electro-conduction circuit is formed by the negative-pole wire harness, the lateral electro-conduction metal plate, the lateral electro-conduction brush device, the floating surface contact electro-conduction device, the straight-seam steel pipe and a welding wire electrode.

An arc welded joint and an arc welding method. The arc welded joint has a weld formed by arc welding of an overlap of at least two steel sheets. A slag-covered area ratio is 20% or less. A Vickers hardness of a weld metal and a Vickers hardness of softened portions of a weld heat affected zone in the weld satisfy a specified relationship.

An arc welded joint and an arc welding method. The arc welded joint has a weld formed by arc welding of an overlap of at least two steel sheets. A slag-covered area ratio is 20% or less. A Vickers hardness of a weld metal and a Vickers hardness of softened portions of a weld heat affected zone in the weld satisfy a specified relationship.

An arc welded joint and an arc welding method. The arc welded joint has a weld formed by arc welding of an overlap of at least two steel sheets. The throat in the weld and the sheet that is uppermost among the steel sheets satisfy a specified relationship. In a region extending 2.0 mm from a bead toe of the weld in a weld metal direction and also extending 2.0 mm from the bead toe in a base material direction, a slag-covered area ratio is 50% or less.

An arc welded joint and an arc welding method. The arc welded joint has a weld formed by arc welding of an overlap of at least two steel sheets. The throat in the weld and the sheet that is uppermost among the steel sheets satisfy a specified relationship. In a region extending 2.0 mm from a bead toe of the weld in a weld metal direction and also extending 2.0 mm from the bead toe in a base material direction, a slag-covered area ratio is 50% or less.

Features herein relate to an electric arc welding method for creating a multi-pass welded joint comprising the following steps: a first stand-alone toe weld on a first construction element, then, arranging the first construction element and a second construction element in a joining position, with a distance being present between the first stand-alone toe weld and a root area of the welded joint to be created, while maintaining the joining position, making a first weld connection between the first construction element and the second construction element by applying a root pass at the root area, then, applying one or more filling beads, wherein the first stand-alone toe weld, the root pass and the one or more filling beads together form part of the welded joint, wherein the first stand-alone toe weld forms the toe of said welded joint at the side of the first construction element.

Features herein relate to an electric arc welding method for creating a multi-pass welded joint comprising the following steps: a first stand-alone toe weld on a first construction element, then, arranging the first construction element and a second construction element in a joining position, with a distance being present between the first stand-alone toe weld and a root area of the welded joint to be created, while maintaining the joining position, making a first weld connection between the first construction element and the second construction element by applying a root pass at the root area, then, applying one or more filling beads, wherein the first stand-alone toe weld, the root pass and the one or more filling beads together form part of the welded joint, wherein the first stand-alone toe weld forms the toe of said welded joint at the side of the first construction element.