Abstract: A plasma arc torch is disclosed having an upper body of a non-conductive material supporting an electrode and a lower body of a conductive material supporting a nozzle through which an arc is formed between the electrode and a work piece. Means is provided for blowing a mixture of inert gas and a fusible powder through a passageway formed in said lower body and through passages formed in said nozzle onto the work piece. A liquid coolant is circulated through a reservoir formed in the lower body, and an inert gas is discharged through an opening that circumvallates the nozzle. Both the nozzle and the torch as a whole are uniquely constructed to avoid many of the problems caused by the use of insulators and fluid seals. In addition, the novelty of construction enhances performance.

Abstract: A ring joint machining tool for simultaneously machining the inner and outer surfaces of a V-groove, said tool having a rotating body member with a sliding tool block holding two tools and having cam means associated with said tool block whereby said tool block moves in a radial direction as the tool is rotated and urged into contact with a workpiece.

Abstract: In a machine for machining metal having a rotating cutting head with a star feed for advancing the cutting head, an adjustable angle drive is provided whereby one can machine a conical concave or convex surface.

Abstract: A grooving bar is provided for machining grooves on the inside surface of a casting or the like, such as the split casing for a pump. The grooving bar of the present invention can be inserted into a casing, adjusted for a precision cut and moved from one cutting location to the next. In accordance with one embodiment of the invention, a geared-down adjustment mechanism is provided for precise feeding of the cutting tool.

Abstract: Volute pumps are frequently used for abrasive liquids such as in the transportation of aqueous slurrys of finely divided coal and similar materials. Since pumps for such purposes are very large, they are ordinarily made as double volute pumps to minimize radial thrust. When pumps are used for abrasive materials, the wear on the pump occurs primarily at the volute lips. In accordance with the present invention, a volute pump is provided with replaceable lips so that the lips can be replaced as they become worn. Further, the lips can be made of a much more resistant material than the body of the pump.