95 results about "Exothermic welding" patented technology

An assembly is disclosed for exothermic welding comprising a mold which is formed of a material which withstands exothermic welding temperatures and includes a weld cavity therein for positioning at least two members which are to be exothermically welded together, and an ignition cavity communicating with the weld cavity. The mold is capable of accommodating any one of several exothermic welding procedures which may involve either a flint igniter or the use of an electrical igniter which is readily accommodated by the mold in the performance of several of the procedures. The electrical igniter is formed of a pair of flat, longitudinally extending conductor strips with a sheet of insulation laminated therebetween, a filament adjacent one end of the strips, and one or more positioning tabs adjacent one end of the strips. A cartridge is also provided which contains the weld metal and the electrical igniter and which may be positioned in the ignition cavity of the mold. The cartridge is formed of a material which is consumed during the welding procedure and may contain a plate of a different material adjacent its bottom which melts at a higher temperature than the materials of the cartridge.

It is an object of the present invention to provide a laser-welded article that workpieces prepared simply can be easily unified by laser in one laser welding process without using complicated processes. Moreover, the laser-welded article has sufficient welding strength of the molded workpieces, and does not damage the resin property.The laser-welded article comprises:an integral construction of a single weakly laser-absorptive molded workpiece or plural weakly laser-absorptive molded workpieces, which is welded by exothermic through irradiating laser under butting at least a part of edge portions thereof, wherein the workpiece or the workpieces include a thermoplastic resin and a weakly laser absorbent to have an absorbance: a ranging from 0.07 to 3.0, and have abilities of absorbing at least partial beam of the laser and transmitting other partial beam of the laser.

Exothermic welding molds, weld-metal containing cartridges for such molds, and methods of use are provided. The mold, cartridges, and methods can provide interaction between the cartridge's disk member with the mold, which allows the housing member to be withdrawn from the mold while leaving the disk member and weld-metal in place. The interaction can be a rotational restraint alone, a vertical restraint alone, or combinations thereof. Alternately, the interaction can be an outward pressure on the housing member and / or disk member, a shear force on the housing member and / or disk member, or combinations thereof. The outward pressure on the housing member and / or disk member can alternately be provided without interaction between the disk member and the mold, but rather by the simple application of an internal pressure to the cartridge. The internal pressure can be applied by squeezing the walls of the cartridge and / or by depressing a pusher member.