Patent attributes
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.