Abstract: A welding control device includes an actual position determination part configured to determine an actual position of the position control target on the basis of a weld characteristic amount detected from a captured image captured so as to include at least the position control target, the welding characteristic amount including at least one of a wire position of the weld wire or an electrode position of the electrode; a target position determination part configured to determine a target position being a target of the actual position corresponding to a weld condition for welding the weld target; and a position control part configured to execute a position control of the position control target to bring the actual position to the target position.

Abstract: A method of performing overlay welding on a member including a steel material and an overlay welded portion made of a cobalt-based alloy and formed on the steel material, the method including generating an arc between a welding torch and the overlay welded portion, forming a melt pool by melting a surface of the overlay welded portion with the arc, and simultaneously inserting a similar-composition welding material having a composition similar to the steel material and a cobalt-based alloy welding material made of a cobalt-based alloy into the melt pool.

Abstract: A welding control device configured to control a position control object which includes at least one of a welding wire used to weld a welding object or an electrode for melting the welding wire includes a first decision unit for deciding an actual position of the position control object based on a welding feature amount detected from an image which is shot to include at least the position control object, a second decision unit for deciding a target position which is a target of the actual position according to an input condition based on the input condition which includes at least one of attitude information of the electrode when the welding object is welded or shape information of the welding object, and a control unit for performing position control of the position control object so that the actual position becomes the target position.

Abstract: A welding control device includes an actual position determination part configured to determine an actual position of the position control target on the basis of a weld characteristic amount detected from a captured image captured so as to include at least the position control target, the welding characteristic amount including at least one of a wire position of the weld wire or an electrode position of the electrode; a target position determination part configured to determine a target position being a target of the actual position corresponding to a weld condition for welding the weld target; and a position control part configured to execute a position control of the position control target to bring the actual position to the target position.

Abstract: A welding method includes welding a base material (1) of low alloy steel which is irradiated with neutrons using a welding material (2) of austenitic stainless steel.

Abstract: A welding method includes welding a base material (1) of low alloy steel which is irradiated with neutrons using a welding material (2) of austenitic stainless steel.

Abstract: A clearance (C) is provided between the inner circumferential surface of cylindrical stubs (22) (which protrude toward the outlet-side and inlet-side water chambers (14, 15) of outlet-side and inlet-side tube plates (11a, 11b)) and the outer circumferential surface at the end part of heat transfer tubes (12) inserted into the stubs (22), and the end faces of the inside tube parts (24a) and the outside tube parts (24b) of grooved end pieces (24) are laser-welded to the end faces of the heat transfer tubes (12) and the stubs (22) from the inner-surface side of the heat transfer tube (12), with the weld height of the end faces of the outside tube parts (24b) and the end faces of the stubs (22) and the weld height of the end faces of the inside tube parts (24a) and the end faces of the heat transfer tubes (12) corresponding to each other, thereby enabling butt-welding to be performed in one pass.

Abstract: A clad welding method, which can prevent the occurrence of incomplete fusion, and can cover the surface of a base material over a wide range with a weld metal, while suppressing the dilution of the weld metal, by use of a relatively simple technique, is provided. For this purpose, a welding heat input is increased at a location where one end (10a) of a preceding weld bead (10) and the other end (20b) of a succeeding weld bead (20) overlap, as compared with a welding heat input at a location where the preceding weld bead (10) and the succeeding weld bead (20) do not overlap, to produce a deep penetration portion (12a) involving locally deep penetration (12).

Abstract: A pipe diameter expansion apparatus includes: a hollow cylindrical member that can be placed in a pipe filled with water, and through which a coolant medium having a lower temperature than a freezing point of the water flows from one end to the other end; at least two plate-like fins provided to protrude outward from the cylindrical member; and a cold-heat insulator that is provided between the two fins, and reduces cold-heat transmission between inside and outside the cylindrical member.

Abstract: A pipe diameter expansion apparatus includes: a hollow cylindrical member that can be placed in a pipe filled with water, and through which a heat medium having a lower temperature than a freezing point of the water flows from one end to the other end; at least two plate-like fins provided to protrude outward from the cylindrical member; and a heat insulator that is provided between the two fins, and reduces heat transmission between inside and outside the cylindrical member.

Abstract: An object is to provide a method and an apparatus for improving a residual stress in a tubular body, which are enabled to improve the residual stress reliably by clearly defining controlling rage for treatment conditions without depending on an installation state and configuration of the tubular body. When a cylindrical tubular body (2) is improved in its residual stress by locally irradiating an outer-circumferential surface of a welded portion (C) of the tubular body (2) with laser beams (5a) and by moving an irradiation area (s) in an circumferential direction, a plurality thermocouples (9) are installed on the tubular body (2) to be improved, a temperature history of the outer surface of the tubular body (2) by the irradiation of the laser beam (5a) is managed by measuring the temperature history itself.

Abstract: An object is to provide a method and an apparatus for improving a residual stress in a tubular body, which are enabled to improve the residual stress reliably by clearly defining controlling rage for treatment conditions without depending on an installation state and configuration of the tubular body. When an outer-circumferential surface of a welded portion of a cylindrical tubular body (2) is irradiated with a laser beam that circles around an outer circumference of the tubular body (2), a heating width W in a circumferential direction heated by the laser-beam irradiation and a laser-beam moving speed V in the circumferential direction are set so that a stress in the circumferential direction in an inner surface of the tubular body (2) produced by the heating with the laser beam is at least larger than a yielding stress of a material that the tubular body (2) is made of.

Abstract: To provide a nozzle welding method which can be performed automatically and efficiently, and which can also be performed under the condition of a high-exposure amount.

Abstract: A clad welding method, which can prevent the occurrence of incomplete fusion, and can cover the surface of a base material over a wide range with a weld metal, while suppressing the dilution of the weld metal, by use of a relatively simple technique, is provided. For this purpose, a welding heat input is increased at a location where one end (10a) of a preceding weld bead (10) and the other end (20b) of a succeeding weld bead (20) overlap, as compared with a welding heat input at a location where the preceding weld bead (10) and the succeeding weld bead (20) do not overlap, to produce a deep penetration portion (12a) involving locally deep penetration (12).

Abstract: An object is to provide a method and an apparatus for improving a residual stress in a tubular body, which are enabled to improve the residual stress reliably by clearly defining controlling rage for treatment conditions without depending on an installation state and configuration of the tubular body. When a cylindrical tubular body (2) is improved in its residual stress by locally irradiating an outer-circumferential surface of a welded portion (C) of the tubular body (2) with laser beams (5a) and by moving an irradiation area (s) in an circumferential direction, a plurality thermocouples (9) are installed on the tubular body (2) to be improved, a temperature history of the outer surface of the tubular body (2) by the irradiation of the laser beam (5a) is managed by measuring the temperature history itself.

Abstract: An object is to provide a method and an apparatus for improving a residual stress in a tubular body, which are enabled to improve the residual stress reliably by clearly defining controlling rage for treatment conditions without depending on an installation state and configuration of the tubular body. When an outer-circumferential surface of a welded portion of a cylindrical tubular body (2) is irradiated with a laser beam that circles around an outer circumference of the tubular body (2), a heating width W in a circumferential direction heated by the laser-beam irradiation and a laser-beam moving speed V in the circumferential direction are set so that a stress in the circumferential direction in an inner surface of the tubular body (2) produced by the heating with the laser beam is at least larger than a yielding stress of a material that the tubular body (2) is made of.

Abstract: An object is to provide a method and a system for improving a residual stress in a tube body, with which the residual stress can reliably be improved without heating excessively. From an irradiation start angle ?s to a first predetermined angle ?1 on the tube body, an intensity of a laser beam is gradually increased from 0.5 to the steady output of 1.0 output ratio; from the first predetermined angle ?1 to a second predetermined angle ?2, the intensity of the laser beam is set at 1.0 output ratio; from the second predetermined angle ?2 to an irradiation end angle ?e, the intensity of the laser beam is gradually decreased from the 1.0 output ratio to 0.5; and at the irradiation end angle ?e, the intensity of the laser beam is set to 0. All these steps are performed at one turn of rotation in the method and the system for improving residual stress in the tube body.

Abstract: A feed length control device for a consumable electrode type welding machine in which the feed length of the electrode is made constant, making the resulting welds satisfactory and with a deep weld penetration. In accordance with the invention, the start of feed length control is delayed for a predetermined period of time from the time instant when the welding current value changes from the peak set value to the base set value.