A plasma torch moves to a piercing position. The plasma torch generates a plasma arc and starts a piercing step at the piercing position. Whether the piercing step is completed is determined based on the arc voltage. The plasma torch is held at the piercing position in the horizontal direction from the start of the piercing step until the completion of the piercing step. The plasma torch is moved in a predetermined direction including at least the horizontal direction after the piercing step is completed.

A method and apparatus for operating a DC plasma torch. The power supply used is at least two times the average operating voltage used, resulting in a more stable operation of the torch. The torch can include two concentric cylinder electrodes, the electrodes can be graphite, and the plasma forming gas can be hydrogen. The power supply provided also has the capability of igniting the torch at a pulse voltage of at least 20 kilovolts.

A method and apparatus for operating a DC plasma torch. The power supply used is at least two times the average operating voltage used, resulting in a more stable operation of the torch. The torch can include two concentric cylinder electrodes, the electrodes can be graphite, and the plasma forming gas can be hydrogen. The power supply provided also has the capability of igniting the torch at a pulse voltage of at least 20 kilovolts.

A system for determining an operational state of an atmospheric pressure plasma. The system has a transformer for coupling power into the atmospheric pressure plasma, a current sampling circuit configured to sample at least one current pulse flowing through a primary winding of the transformer, and a programmed microprocessor configured to determine, from a waveform of the current pulse, the operational state of the atmospheric pressure plasma. The operational state is one of: a no plasma state, a plasma origination state indicative of an ignited arc expanding into a plasma by gas flow thereinto, and a plasma maintenance state indicative of the plasma being expanded.

A system for determining an operational state of an atmospheric pressure plasma. The system has a transformer for coupling power into the atmospheric pressure plasma, a current sampling circuit configured to sample at least one current pulse flowing through a primary winding of the transformer, and a programmed microprocessor configured to determine, from a waveform of the current pulse, the operational state of the atmospheric pressure plasma. The operational state is one of: a no plasma state, a plasma origination state indicative of an ignited arc expanding into a plasma by gas flow thereinto, and a plasma maintenance state indicative of the plasma being expanded.

In some aspects, methods for preserving a usable life of a plasma arc electrode consumable installed in a plasma arc torch can include measuring a characteristic of an electrical signal being provided to the torch to generate a plasma arc between the torch and a workpiece to be processed; monitoring the characteristic during operation of the torch over a time period; comparing the characteristic to a threshold value; and, responsive to determining that a measured characteristic meets and/or exceeds the threshold value, initiating an arc extinguishing sequence to preserve the life of the electrode.

In some aspects, methods for preserving a usable life of a plasma arc electrode consumable installed in a plasma arc torch can include measuring a characteristic of an electrical signal being provided to the torch to generate a plasma arc between the torch and a workpiece to be processed; monitoring the characteristic during operation of the torch over a time period; comparing the characteristic to a threshold value; and, responsive to determining that a measured characteristic meets and/or exceeds the threshold value, initiating an arc extinguishing sequence to preserve the life of the electrode.

A system for providing a dynamically controlled plasma cutting system. The plasma cutting system includes a proportional valve and a sensing device arrangement and a controller connected to this arrangement. The system is configured to dynamically control gas flow in a plasma torch. The system measures gas pressure at a proportional valve and makes necessary gas pressure adjustments in the system by way of controlling a drive signal sent to the proportional valve to control gas flow.

A system for providing a dynamically controlled plasma cutting system. The plasma cutting system includes a proportional valve and a sensing device arrangement and a controller connected to this arrangement. The system is configured to dynamically control gas flow in a plasma torch. The system measures gas pressure at a proportional valve and makes necessary gas pressure adjustments in the system by way of controlling a drive signal sent to the proportional valve to control gas flow.

A system for generating magnetized plasma and sustaining plasma's magnetic field comprises a plasma generator for generating magnetized plasma and a flux conserver in which the generated magnetized plasma is injected and confined. A central conductor comprises an upper central conductor and a lower central conductor that are electrically connected forming a single integrated conductor. The upper central conductor and an outer electrode form an annular plasma propagating channel. The lower central conductor extends out of the plasma generator and into the flux conserver such that an end of the inner electrode is electrically connected to a wall of the flux conserver. A power system provides a formation current pulse and a sustainment current pulse to the central conductor to form the magnetized plasma, inject such plasma into the flux conserver and sustain plasma's magnetic field.