Abstract: A series of replacement parts for use in a plasma arc torch is provided, wherein the parts have a color indicia and are adapted for use at different operating parameter values. Each part in the series has a color indicia formed on the part with a different color identifying the particular value of the operating parameter at which the part is adapted to operate. In another form, each part in the series is packaged in a package with a different color indicia identifying the particular value of the operating parameter at which the part is adapted to operate. Additionally, methods of packaging, applying the color indicia, selecting a package or part, and specifying a package or part are provided by the present invention.

Abstract: A trigger system for operating a plasma arc torch is provided that comprises a selector that operates between at least a first operating position and a second operating position, wherein the first operating position operates the plasma arc torch in a first mode to deliver gas to the plasma arc torch, and the second operating position operates the plasma arc torch in a second mode to deliver the gas and electric power to the plasma arc torch. Further, the selector comprises a neutral position that selects a neutral mode in which delivery of gas and electric power to the plasma arc torch is inhibited. The selector is preferably disposed within a housing of the plasma arc torch and is slidably operable between the first operating position, the second operating position, and the neutral position.

Abstract: Vented shield systems for plasma arc torches are provided that comprise a shield cup body defining a distal end portion, a vented retainer secured to the distal end portion of the shield cup body, and a shield cap secured to the vented retainer. The vented retainer defines at least one vent passageway that directs a flow of secondary gas inward toward the shield cap, and the vented shield system blocks at least a portion of molten metal from contacting components, such as a tip or nozzle, of the plasma arc torch. The shield cap may comprise a mechanized cap, a drag cap, a gouging cap, or a deflector cap, among others. Accordingly, various shield caps may be employed without removal or replacement of the vented retainer. The same vented retainer may be used throughout a variety of plasma arc torch applications.

Abstract: A tip for a plasma arc torch includes a ridge for improved electrical contact with a starting member.

Abstract: A plasma arc torch and method for improving the life of the consumable parts of the plasma arc torch, including the electrode, the tip and the shield cap. The method includes turbulating gas as it flows over the exposed surfaces of the electrode, tip and shield cap to increase turbulence in the hydrodynamic boundary layer of the gas flow, thereby enhancing convective heat transfer. The result of enhanced cooling is improved consumable parts life. For example, to increase the turbulence of the gas flow over the outer surface of the electrode, the plasma arc torch electrode has a roughened, or textured outer surface formed with dimples, axially extending grooves or spiraling grooves formed in the outer surface of the electrode. The inner and outer surfaces of the tip and the inner surface of the shield cap are similarly textured.

Abstract: A plasma torch and method for cutting a workpiece under water directs a primary gas through a primary gas flow path in the torch to a central exit opening of the torch disposed on a longitudinal axis of the torch for exhaustion from the torch onto the workpiece in the form of an ionized plasma. The workpiece is submerged in water while the plasma torch is operated in closely spaced relationship with the workpiece to direct the ionized plasma upon the workpiece. A secondary gas flow path in the torch receives a secondary gas separate from the primary gas and directs it through the torch. Concentrically arranged first and second sets of secondary exit openings are disposed in the torch separate from the central exit opening and in generally radially spaced relationship with the longitudinal axis of the torch. The secondary exit openings exhaust secondary gas from the torch in a direction generally toward the workpiece.

Abstract: The apparatus is a combined Alkali Metal Thermal to Electric Converter (AMTEC) and a thermionic energy converter which are mated by the use of a common heat transfer device which can be a heat pipe, pumped fluid or a simple heat conduction path. By adjusting the heat output surface area of the thermionic converter and the heat input surface area of the AMTEC, the heat transfer device accomplishes not only the transfer of heat from the output of the thermionic converter to the input of the AMTEC, but also the transformation of the heat density to match the requirements of the AMTEC input. The electrical current through the combined devices is also matched by adjusting the heated surface area of the AMTEC.

Abstract: A thermionic electric converter module integrated with heating and cooling heat pipes. Two heat pipes are arranged concentrically, with the annular emitter heat pipe on the outside of the module to isothermally distribute heat from a source located in any direction around the unit to the emitter located on the inside exterior wall of the heat pipe. The exterior wall surface of the collector heat pipe, located inside the annular emitter heat pipe, is separated from the emitter by the thermionic converter's interelectrode gap and serves as the collector of the thermionic converter. The collector heat pipe is of conventional cylindrical configuration and transports the waste heat of the thermionic converter along the unit's axis to a remote location for disposal.