Abstract: This coupling device for a tubular member is provided with: a base stand for holding an inner member and an outer member in a state in which the outer member is disposed around the inner member; a plurality of pressing members that are supported by the base stand in a movable manner in the radial direction of the inner member and the outer member and have a protruding part on the tip thereof; a pressing member that make contact with the final end of the pressing member and that can press the pressing member radially inward; and a drive mechanism that drives any one among the base stand and the pressing member in a direction perpendicular to the movement direction of the pressing member so that the one member moves relative to the other.

Abstract: A gas-shielded arc welding method includes welding a steel plate having a tensile strength of 780 MPa or more while feeding a consumable electrode via a welding torch and flowing a shielding gas. The consumable electrode includes, in mass %, C: 0 to 0.20%, Si: 0 to 0.50%, Mn: 0 to 0.50%, Cr: 1.00% to 9.00%, S: 0.0020% to 0.0600%, and Ni: 0 to 0.50%. The shielding gas includes, in vol. %, at least one of CO2 and O2: 1% to 15% in total, with the remainder being Ar and unavoidable impurities. Welding is performed under the condition satisfying the relationship of 1?{?0.05×[CO2+O2]}+[Cr]?8.3, and [Cr] represents the content of Cr in the consumable electrode, and [CO2+O2] represents a total content of at least one of CO2 and O2 in the shielding gas.

Abstract: A coil component includes a core including a winding core portion and a first flange portion that is disposed on a first end portion of the winding core portion in a direction in which the winding core portion extends. A first curved portion is formed at a connection between a bottom surface of the winding core portion and the first flange portion. A ratio of a length of the first curved portion in a height direction to a distance in the height direction between the bottom surface and a first terminal electrode is no less than 20% and no more than 60% (i.e., from 20% to 60%).

Abstract: This arc spot welding method for dissimilar materials joins a steel upper plate and a non-ferrous metal lower plate. The upper plate has a flat plate-like base part and an upright wall part erected on the base part. The base part has a through-hole. The arc spot welding method for dissimilar materials includes superposing the base part on the lower plate so that the lower plate faces the base part via the through-hole; and arc-welding the base part and the lower plate by filling the through-hole with a molten weld metal at a position, which is a target position, offset in the direction opposite the upright wall part from the center of the through-hole.

Abstract: A joint structure, includes: a first member including a high tensile strength steel; a second member including a high tensile strength steel and superposed on the first member; a surface soft layer formed on at least one of a superposition surface of the first member, on which the second member is superposed, and a superposition surface of the second member, on which the first member is superposed; a molten-solidified portion formed by melting and solidifying the first member and the second member; and a heat affected zone formed around the molten-solidified portion, in which the surface soft layer has a total thickness of 5 ?m to 200 ?m, and the molten-solidified portion has a carbon amount of 0.21 mass % or more, and a maximum Vickers hardness of the surface soft layer in the heat affected zone is 100 Hv to 500 Hv.

Abstract: A resistance welding method for joining together a first member and a second member with an element including a head portion and a shaft portion. The method includes: contacting the shaft portion with the first member to stack the element, the first member, and the second member in this order; sandwiching and pressurizing the element, the first member, and the second member with a pair of electrodes while pressurizing at least one of the element or the first member with an external pressurizing jig disposed around at least one electrode of the pair of electrodes that is closer to the element; and melting the first member by energization of the pair of electrodes while maintaining pressurization with the pair of electrodes and the external pressurizing jig so that the element penetrates the first member to weld the element and the second member together.

Abstract: The present invention relates to a method for joining a plated steel sheet, in which at least one of a first steel sheet and a second steel sheet is a plated steel sheet, and the first and second steel sheets overlapped with each other are subjected to an arc spot welding. The method includes press-working the first steel sheet into a desired shape and at the same time forming a linear groove on an overlapping surface with the second steel sheet of the first steel sheet, overlapping the first and second steel sheets, and setting a welding torch with the groove as a target position, and performing the arc spot welding so as to overlap the groove when viewed from a direction perpendicular to the overlapping surface.

Abstract: The arc spot welding method for joining dissimilar materials, in which a first sheet (10) made of an Al-based material or an Mg-based material and a second sheet (20) made of ultra-high tensile steel having a tensile strength of 1180 MPa or more are joined, includes a step of forming a hole in the first sheet (10), a step of overlapping the first sheet (10) and the second sheet (20), a step of inserting a joining auxiliary member (30) made of steel, in which a hollow portion is formed, into the hole of the first sheet (10), and a step of joining the first sheet (10) and the second sheet (20) via the joining auxiliary member (30) using a welding material containing 13 mass % or more of Ni.

Abstract: A method for manufacturing a joint structure formed by joining a first plate-shaped member and a second plate-shaped member having a shape that is longer in a longitudinal direction than in a lateral direction includes overlapping the first plate-shaped member and the second plate-shaped member, after the overlapping, joining each of both edge portions of the second plate-shaped member by forming a weld metal along the longitudinal direction to the first plate-shaped member. The weld metal extends further outward in the lateral direction than the edge portions of the second plate-shaped member, in which the weld metal is formed by a hybrid welding in which a laser is added as a heat source during arc welding such that the weld metal extends around both of the edge portions of the second plate-shaped member along the longitudinal direction.

Abstract: A method for manufacturing a dissimilar material joint structure by joining a steel material and an aluminum or aluminum alloy material having a low-temperature spray coating made of a metal powder capable of being joined to the steel material on at least a part of a surface of the aluminum or aluminum alloy material. The method includes overlapping the aluminum or aluminum alloy material and the steel material such that the low-temperature spray coating and the steel material face each other and emitting a laser beam from a steel material side. Where a region to be irradiated with the laser beam includes a first region where at least the steel material and the low-temperature spray coating are melted, and a second region where the steel material and the low-temperature spray coating are not melted in a peripheral portion of the first region.

Abstract: A lap fillet weld joint and a lap fillet weld joint manufacturing method are provided. On a side of a first edge, a first metal plate is provided with a bulging portion that has an internal space of a prescribed size, and a second metal plate has a protruding portion that faces to the bulging portion and can be inserted into the bulging portion. In a state in which the protruding portion has been inserted into the bulging portion, the first metal plate and a second edge of the second metal plate are welded, and a first weld bead is formed.

Abstract: A method for producing a resistance-welded member made of three or more sheets including a plated steel sheet includes: a main energizing by performing energization with a first current value while compressing the steel sheet with a first compressive force to form a nugget; a subsequent energizing by performing, after the main energizing, energization such that the current value gradually decreases from the first current value while compressing with a second compressive force greater than the first compressive force; and holding an electrode while maintaining the second compressive force after the subsequent energizing. The second compressive force and a total sheet thickness, compression rise delay time, and a downslope time and an electrode holding time satisfy respective predetermined conditions.

Abstract: A method for producing a resistance-welded member made of three or more sheets including a plated steel sheet that includes: a first energizing with a first current value while compressing the steel sheets with a first compressive force to form a nugget; a subsequent energizing of, after the first energizing, energizing with a second current value smaller than the first current value while compressing the steel sheets with a second compressive force greater than the first compressive force; and holding an electrode by maintaining the second compressive force after the subsequent energization. The second compressive force and a total sheet thickness, the first current value and the second current value, and a subsequent energization time and an electrode holding time satisfy predetermined conditions respectively.

Abstract: A joint body includes first and second metal members and a joint portion including a welded portion where the first and second metal members are joined together, the welded portion having a line shape. The joint portion includes first and second longitudinal portions and a plurality of connecting portions. The first longitudinal portion has first intersecting portions arranged in a first direction and extends in the first direction. The second longitudinal portion has second intersecting portions arranged in the first direction and extends in the first direction. The welded portion intersects itself at the first and second intersecting portions. The connecting portions are arranged in the first direction. The connecting portions extend in a first direction and connect the first and second longitudinal portions.

Abstract: A welding system includes a welding torch that welds a workpiece by using a wire, a suction device that sucks shielding gas, and a sucked shielding gas supply path for allowing the sucked shielding gas to flow, wherein the welding torch includes a contact chip that guides the wire, a shielding gas supply nozzle that supplies the shielding gas to a weld zone, and a suction nozzle that surrounds a periphery of the wire protruding from the contact chip, and is opened toward a tip of the wire to suck the shielding gas.

Abstract: A welding torch for arc welding in a shielding gas atmosphere, includes: a contact tip for feeding a welding wire; a suction nozzle surrounding the welding wire, and sucking a gas from a space between the suction nozzle and the welding wire; and a shielding gas supply nozzle provided on the outer periphery of the suction nozzle, and supplying the shielding gas toward a welded portion from a space between the shielding gas supply nozzle and the suction nozzle. The welding torch satisfies “7?Ltk?17 and 0?Lts?18”, where Lts [mm] is a distance between the tip of the contact tip and the tip of the shielding gas supply nozzle, and Ltk [mm] is a distance between the tip of the contact tip and the tip of the suction nozzle.

Abstract: A manufacturing method for a joint body having a first metal member and a second metal member joined together by causing a laser oscillation system to irradiate a surface of the second metal member placed on the first metal member with laser light to form a joint portion including a welded portion where the first metal member and the second metal member are joined together includes continuously supplying the second metal member while pressing the second metal member against the first metal member, the second metal member being a hoop material, and causing the laser oscillation system to emit the laser light.

Abstract: A method for manufacturing a dissimilar metal joint product including joining a first member made of non-ferrous metal and having an end surface and a first surface adjacent to the end surface and a second member made of steel, the method includes: spraying a metal powder capable of being joined to the second member to the end surface and the first surface of the first member at a low temperature and at a high speed to form a coating to extend over the end surface and the first surface; disposing the first member and the second member such that the coating and the second member are close to or contact with each other; and performing fillet welding between the coating and the second member.

Abstract: This coupling device for a tubular member is provided with: a base stand for holding an inner member and an outer member in a state in which the outer member is disposed around the inner member; a plurality of pressing members that are supported by the base stand in a movable manner in the radial direction of the inner member and the outer member and have a protruding part on the tip thereof; a pressing member that make contact with the final end of the pressing member and that can press the pressing member radially inward; and a drive mechanism that drives any one among the base stand and the pressing member in a direction perpendicular to the movement direction of the pressing member so that the one member moves relative to the other.

Abstract: A method for manufacturing a joint structure of dissimilar materials, the method includes: forming a low-temperature thermal spray coating on at least a part of a surface of an aluminum or aluminum alloy material by low-temperature thermal spraying a metal powder of at least one metal selected from the group consisting of pure iron, carbon steel, stainless steel, nickel, a nickel alloy, cobalt, and a cobalt alloy; overlapping the aluminum or aluminum alloy material and a steel material such that the low-temperature thermal spray coating and the steel material face each other; and joining the aluminum or aluminum alloy material and the steel material by laser a welding from a steel material side, in which the joining is performed under welding conditions in which a fusion zone is formed in the steel material, the low-temperature thermal spray coating, and the aluminum or aluminum alloy material.