An aluminothermic welding device for and a method of welding together of first and second pipe members (10, 12) are described. A sleeve (30) is configured to cover both pipe members (10, 12) and to form a cavity (33) surrounding said pipe members (10, 12) when it is in a welding position. A crucible (50) is also provided, wherein a drain channel (44) is connected to a second opening in a wall of said sleeve (30), in an upper part of said sleeve (30) when said sleeve is in said welding position. Said second opening is configured to drain gases and dross from said cavity (33). There is further an input channel (54) between said crucible (50) and said cavity (33), wherein said input channel (54) enters into said cavity (33) through a first opening in a wall of said sleeve (30) in a lower part of said sleeve (30), when said sleeve (30) is in said welding position.

Trigger devices for igniting an exothermic reaction is provided. The trigger devices may be flint type trigger devices and electronic type trigger devices. The flint type trigger device has a housing with a spark opening on a rear wall of the housing. A mold mounting assembly is secured to an exterior of the rear wall of the housing. A motor assembly is secured to the inside of the rear wall of the housing. The motor assembly has a flint wheel attached to a shaft of a motor, where the flint wheel is located adjacent the spark opening. A flint assembly is positioned within the housing such that a flint of the flint assembly is in contact with the flint wheel. A controller positioned within the housing is configured to selectively activate the motor to cause the flint wheel to rotate against the flint to create one or more sparks that are ejected from the spark opening.

Trigger devices for igniting an exothermic reaction is provided. The trigger devices may be flint type trigger devices and electronic type trigger devices. The flint type trigger device has a housing with a spark opening on a rear wall of the housing. A mold mounting assembly is secured to an exterior of the rear wall of the housing. A motor assembly is secured to the inside of the rear wall of the housing. The motor assembly has a flint wheel attached to a shaft of a motor, where the flint wheel is located adjacent the spark opening. A flint assembly is positioned within the housing such that a flint of the flint assembly is in contact with the flint wheel. A controller positioned within the housing is configured to selectively activate the motor to cause the flint wheel to rotate against the flint to create one or more sparks that are ejected from the spark opening.

An exothermic welding cup and an exothermic welding capsule, wherein the exothermic welding cup comprises a cup, a cover and an igniter; the cup is used to accommodate welding powder, the cup has an opening, and the cover is used to cover the opening; the igniter comprises a heating portion disposed in the cup, and the heating portion has an insulating member and a heating member; and the insulating member is disposed between the heating member and the cover. The exothermic welding cup can avoid the shorting caused by the contact between the heated heating member and the cover. Also, an encapsulation ring disposed between the cover and the cup is configured to seal the welding powder within the cup so as to prevent the powder from falling out, and the encapsulation ring made of stainless steel ensures effective encapsulation of the welding powder within a certain welding time.

An exothermic welding cup and an exothermic welding capsule, wherein the exothermic welding cup comprises a cup, a cover and an igniter; the cup is used to accommodate welding powder, the cup has an opening, and the cover is used to cover the opening; the igniter comprises a heating portion disposed in the cup, and the heating portion has an insulating member and a heating member; and the insulating member is disposed between the heating member and the cover. The exothermic welding cup can avoid the shorting caused by the contact between the heated heating member and the cover. Also, an encapsulation ring disposed between the cover and the cup is configured to seal the welding powder within the cup so as to prevent the powder from falling out, and the encapsulation ring made of stainless steel ensures effective encapsulation of the welding powder within a certain welding time.

The present invention relates to a moulding assembly for aluminothermic welding of metal rails (30), comprising at least one mould part (1, 50) configured to come into contact with at least one other mould part (1, 50) and rails (30) to be welded in order to form a mould cavity (102) in which the ends (31) of the metal rails to be welded are arranged and into which a molten metal is cast in order to weld the metal rails (30), the moulding assembly being characterised in that each mould part (1, 50) comprises a seating (13) configured to be placed in contact with at least one of said rails (30), said seating (13) comprising a groove (60) into which a sealing product (40) made of intumescent material is applied.

The present invention relates to a moulding assembly for aluminothermic welding of metal rails (30), comprising at least one mould part (1, 50) configured to come into contact with at least one other mould part (1, 50) and rails (30) to be welded in order to form a mould cavity (102) in which the ends (31) of the metal rails to be welded are arranged and into which a molten metal is cast in order to weld the metal rails (30), the moulding assembly being characterised in that each mould part (1, 50) comprises a seating (13) configured to be placed in contact with at least one of said rails (30), said seating (13) comprising a groove (60) into which a sealing product (40) made of intumescent material is applied.

A technique facilitates a welding operation in a variety of difficult environments, including downhole environments, to enable formation a dependable connection between components. A tool may be constructed to contain a material mixture used in the welding operation. The tool is conveyed to a position adjacent a weld region of components to be welded together. The material mixture is of a type which may be ignited to initiate a reaction which forms a molten metal from at least one constituent in the material mixture. Additionally, the tool comprises a nozzle oriented to direct the molten metal to the weld region so as to form a secure, welded connection between the components.

A technique facilitates a welding operation in a variety of difficult environments, including downhole environments, to enable formation a dependable connection between components. A tool may be constructed to contain a material mixture used in the welding operation. The tool is conveyed to a position adjacent a weld region of components to be welded together. The material mixture is of a type which may be ignited to initiate a reaction which forms a molten metal from at least one constituent in the material mixture. Additionally, the tool comprises a nozzle oriented to direct the molten metal to the weld region so as to form a secure, welded connection between the components.

An exothermic welding apparatus and an exothermic welding method, belonging to the exothermic welding field are provided. The exothermic welding apparatus includes a mold, an igniter and an electronic starter, the mold has a holding space configured to accommodate an exothermic welding flux, the igniter includes a heating wire, a first conductor wire and a first connector, the heating wire is configured to ignite the exothermic welding flux directly, one end of the first conductor wire is electrically connected to the heating wire, the other end of the first conductor wire is electrically connected to the first connector, and the electronic starter cooperates with the first connector and is configured to supply power to the first connector. The exothermic welding apparatus can ignite an exothermic welding flux by supplying power with an electronic starter.