Abstract: A plasma arc system includes a single-gas, gas-cooled plasma arc torch and a torch control unit. The torch control unit includes a housing and a user input device on the housing for receiving an indication of a desired cutting or marking function and for providing a responsive signal. A single gas supply both to the housing, and from the housing to the torch, is provided for cutting or marking. A current control device is located within the housing for controlling current output to the torch for either cutting or marking. A gas control device is located within the housing for controlling gas output to the torch for either cutting or marking. A controller is located within the housing for receiving the signal from the user input device indicating the desired cutting or marking function, and for sending a responsive signal to the current control and gas control devices depending on the desired cutting or marking function so that the torch operates accordingly. A related control until is disclosed.

Abstract: Electrodes are disclosed for use in a non-contact initiation plasma arc torch, the electrodes including an electrode body having a distal end opposing the outlet of the nozzle and a tapered section adjacent the distal end configured so that the electrode diameter decreases in the direction of the distal end. The electrode tapered section includes at least one discontinuity forming an edge, the edge being disposed as so to have an included angle of no greater than about 90 degrees. The configuration of the edge provides a localized enhancement of electrical field during non-contact initiation of a pilot arc using the electrode. The discontinuity and edge can be formed in various ways. Related torch designs including nozzles are disclosed.

Abstract: A plasma arc system includes a single-gas, gas-cooled plasma arc torch and a torch control unit. The torch control unit includes a housing and a user input device on the housing for receiving an indication of a desired cutting or marking function and for providing a responsive signal. A single gas supply both to the housing, and from the housing to the torch, is provided for cutting or marking. A current control device is located within the housing for controlling current output to the torch for either cutting or marking. A gas control device is located within the housing for controlling gas output to the torch for either cutting or marking. A controller is located within the housing for receiving the signal from the user input device indicating the desired cutting or marking function, and for sending a responsive signal to the current control and gas control devices depending on the desired cutting or marking function so that the torch operates accordingly. A related control until is disclosed.

Abstract: Electrodes are disclosed for use in a non-contact initiation plasma arc torch, the electrodes including an electrode body having a distal end opposing the outlet of the nozzle and a tapered section adjacent the distal end configured so that the electrode diameter decreases in the direction of the distal end. The electrode tapered section includes at least one discontinuity forming an edge, the edge being disposed as so to have an included angle of no greater than about 90 degrees. The configuration of the edge provides a localized enhancement of electrical field during non-contact initiation of a pilot arc using the electrode. The discontinuity and edge can be formed in various ways. Related torch designs including nozzles are disclosed.