An arc spot welding method able to give a predetermined weld bead diameter or excess metal height in a back surface weld bead of arc spot welding and able to give a welded joint excellent in both strengths of TSS and CTS and a welding apparatus for working the same are provided. A steel sheet containing carbon in 0.2 mass % or more and having a sheet thickness “t” and at least one steel sheet containing carbon in 0.2 mass % or more and having a sheet thickness of “t” or more are arranged overlaid, a backing plate comprising a non-contact part and a contact part maintaining the back surface of the lower side steel sheet and the non-contact part in a non-contact state is arranged so that the contact part contacts the back surface of the lower side steel sheet at a position exceeding 3t from the circle equivalent center of the back surface weld bead, and arc generation and short-circuit conduction where the welding voltage between the welding wire and upper side steel sheet becomes 10V or less are alternately repeated so that the time period of the short-circuit conduction becomes over 30% to less than 60% per cycle to thereby weld the steel sheet.

An arc spot welding method able to give a predetermined weld bead diameter or excess metal height in a back surface weld bead of arc spot welding and able to give a welded joint excellent in both strengths of TSS and CTS and a welding apparatus for working the same are provided. A steel sheet containing carbon in 0.2 mass % or more and having a sheet thickness “t” and at least one steel sheet containing carbon in 0.2 mass % or more and having a sheet thickness of “t” or more are arranged overlaid, a backing plate comprising a non-contact part and a contact part maintaining the back surface of the lower side steel sheet and the non-contact part in a non-contact state is arranged so that the contact part contacts the back surface of the lower side steel sheet at a position exceeding 3t from the circle equivalent center of the back surface weld bead, and arc generation and short-circuit conduction where the welding voltage between the welding wire and upper side steel sheet becomes 10V or less are alternately repeated so that the time period of the short-circuit conduction becomes over 30% to less than 60% per cycle to thereby weld the steel sheet.

The present invention relates to an ignition device for exothermic welding comprising an electrically conductive metal bushing (1) that can house a pellet of a first welding material (4) in electrical contact with the inner wall of an inner chamber (1c) of the bushing (1), provided with an electrically insulating cap (2) and a bottom base (1b) with an opening (1d) through which the first welding material (4) falls in an incandescent state onto a second welding material (4a) arranged in a weld mold (7) when an exothermic reaction has been triggered in the first welding material (4); an electrode (5) that goes through the cap (2) of the metal bushing (1) and comprises a top contact (5a) connectable to a power output (24) of a voltage generator and a bottom contact in the form of a filament (5b) that can be in electrical contact with the pellet of the first welding material (4), the filament (5b) being made of a material having a melting temperature greater than the ignition temperature of the welding material (4); as well as a contact-assuring element (3) which is guided into the inner chamber (1c) between the bottom base (1b) and the pellet of the first welding material (4).

The present invention relates to an ignition device for exothermic welding comprising an electrically conductive metal bushing (1) that can house a pellet of a first welding material (4) in electrical contact with the inner wall of an inner chamber (1c) of the bushing (1), provided with an electrically insulating cap (2) and a bottom base (1b) with an opening (1d) through which the first welding material (4) falls in an incandescent state onto a second welding material (4a) arranged in a weld mold (7) when an exothermic reaction has been triggered in the first welding material (4); an electrode (5) that goes through the cap (2) of the metal bushing (1) and comprises a top contact (5a) connectable to a power output (24) of a voltage generator and a bottom contact in the form of a filament (5b) that can be in electrical contact with the pellet of the first welding material (4), the filament (5b) being made of a material having a melting temperature greater than the ignition temperature of the welding material (4); as well as a contact-assuring element (3) which is guided into the inner chamber (1c) between the bottom base (1b) and the pellet of the first welding material (4).

A device for surfacing a metal alloy part by laser welding, the part including a recess to be surfaced and located at a planar area of the part, the device including first and second protective elements arranged on either side of the recess, the first and second protective elements each having an irradiation surface which is to be at least partially covered with a layer of powder to enable welding by passing a laser beam over the powder, the laser beam passing over the irradiation surface of the first protective element during welding and then the irradiation surface of the second protective element, the second protective element having a shape for containing a layer of powder having a height that is greater at the end, in the direction of propagation of the laser beam during welding, of the second protective element than at the start of the second protective element.

A device for surfacing a metal alloy part by laser welding, the part including a recess to be surfaced and located at a planar area of the part, the device including first and second protective elements arranged on either side of the recess, the first and second protective elements each having an irradiation surface which is to be at least partially covered with a layer of powder to enable welding by passing a laser beam over the powder, the laser beam passing over the irradiation surface of the first protective element during welding and then the irradiation surface of the second protective element, the second protective element having a shape for containing a layer of powder having a height that is greater at the end, in the direction of propagation of the laser beam during welding, of the second protective element than at the start of the second protective element.

A method for manufacturing an additively-manufactured object, in which a plurality of weld beads obtained by melting and solidifying a filler metal are deposited on a base portion to build a built-up object, includes: a support bead forming step of forming a support bead on the base portion; and a depositing step of depositing a weld bead on the support bead. When the support bead is formed to be inclined from a vertical direction in the support bead forming step, a ratio H/W of a height H to a width W of the support bead is set to 0.35 or more.

A method for manufacturing an additively-manufactured object, in which a plurality of weld beads obtained by melting and solidifying a filler metal are deposited on a base portion to build a built-up object, includes: a support bead forming step of forming a support bead on the base portion; and a depositing step of depositing a weld bead on the support bead. When the support bead is formed to be inclined from a vertical direction in the support bead forming step, a ratio H/W of a height H to a width W of the support bead is set to 0.35 or more.

The present application relates to a stencil device (150) for simultaneous stencil printing of brazing material onto elevations, areas surrounding port openings, and a circumferential skirt (210) of a heat exchanger plate (200) wherein the stencil device (150) comprises an upper stencil having openings for applying brazing material to elevations and areas surrounding port openings of the heat exchanger plate (200) and a lower stencil printing stencil (150) having a large opening (190) for receiving the heat exchanger plate (200) and contacting an outer perimeter of the circumferential skirt (210) of the heat exchanger plate (200), wherein an inner surface (195) of the large opening (190) comprises brazing material exits (160) for applying brazing material to the circumferential skirts (195). Disclosed is also a method of such stencil printing and also the use of a stencil device for applying heat exchanger plates (200) with a brazing material.

The present application relates to a stencil device (150) for simultaneous stencil printing of brazing material onto elevations, areas surrounding port openings, and a circumferential skirt (210) of a heat exchanger plate (200) wherein the stencil device (150) comprises an upper stencil having openings for applying brazing material to elevations and areas surrounding port openings of the heat exchanger plate (200) and a lower stencil printing stencil (150) having a large opening (190) for receiving the heat exchanger plate (200) and contacting an outer perimeter of the circumferential skirt (210) of the heat exchanger plate (200), wherein an inner surface (195) of the large opening (190) comprises brazing material exits (160) for applying brazing material to the circumferential skirts (195). Disclosed is also a method of such stencil printing and also the use of a stencil device for applying heat exchanger plates (200) with a brazing material.