Abstract: A nozzle for a liquid-cooled plasma arc torch is provided. The nozzle includes a thermally conductive body having a distal end, a proximal end, and a longitudinal axis extending therethrough. The nozzle also includes a plasma arc exit orifice at the distal end of the thermally conductive body. The nozzle additionally includes a cooling waist located circumferentially about an exterior surface of the thermally conductive body. The cooling waist includes a liquid inlet slope, a liquid outlet slope and a heat exchange region between the liquid inlet slope and the liquid outlet slope. The heat exchange region extends substantially parallel to the longitudinal axis, and the liquid inlet slope and the liquid outlet slope are oriented generally perpendicular to the longitudinal axis.

Abstract: The invention features methods and apparatuses for liquid cooling a plasma arc torch. An electrode is provided including a body having a longitudinal axis defining a first end, a second end, and a middle portion. The electrode includes a first sealing element disposed on an exterior of the body near the first end; a second sealing element disposed on the exterior of the body located in the middle portion, the second sealing element configured to provide a first gas seal to a swirl gas chamber and defining a portion of the swirl gas chamber; and a third sealing element disposed on the exterior of the body, the third sealing element located between the second sealing element and the second end, the third sealing element configured to provide a second gas seal to the swirl gas chamber and defining a portion of the swirl gas chamber.

Abstract: A method of using a coolant tube in a liquid cooled plasma arc torch is provided. The method includes installing the coolant tube and a first electrode in the plasma arc torch. The method also includes biasing, by a first coolant flow, a biasing surface of the coolant tube against the first electrode, such that the coolant tube translates axially along the longitudinal axis to contact the first electrode. The biasing by the first coolant flow defines a first distance in an axial direction between the O-ring of the coolant tube and a proximal end of the first electrode. The method further includes removing the first electrode from the plasma arc torch and installing a second electrode in the torch. The method includes biasing, by a second coolant flow, the biasing surface of the coolant tube against the second electrode, such that the coolant tube translates axially along the longitudinal axis to contact the second electrode.

Abstract: A method of using a coolant tube in a liquid cooled plasma arc torch is provided. The method includes installing the coolant tube and a first electrode in the plasma arc torch. The method also includes biasing, by a first coolant flow, a biasing surface of the coolant tube against the first electrode, such that the coolant tube translates axially along the longitudinal axis to contact the first electrode. The biasing by the first coolant flow defines a first distance in an axial direction between the O-ring of the coolant tube and a proximal end of the first electrode. The method further includes removing the first electrode from the plasma arc torch and installing a second electrode in the torch. The method includes biasing, by a second coolant flow, the biasing surface of the coolant tube against the second electrode, such that the coolant tube translates axially along the longitudinal axis to contact the second electrode.

Abstract: A nozzle for a liquid-cooled plasma arc torch is provided. The nozzle includes a thermally conductive body having a distal end, a proximal end, and a longitudinal axis extending therethrough. The nozzle also includes a plasma arc exit orifice at the distal end of the thermally conductive body. The nozzle additionally includes a cooling waist located circumferentially about an exterior surface of the thermally conductive body. The cooling waist includes a liquid inlet slope, a liquid outlet slope and a heat exchange region between the liquid inlet slope and the liquid outlet slope. The heat exchange region extends substantially parallel to the longitudinal axis, and the liquid inlet slope and the liquid outlet slope are oriented generally perpendicular to the longitudinal axis.

Abstract: The invention features methods and apparatuses for liquid cooling a plasma arc torch. An electrode is provided including a body having a longitudinal axis defining a first end, a second end, and a middle portion. The electrode includes a first sealing element disposed on an exterior of the body near the first end; a second sealing element disposed on the exterior of the body located in the middle portion, the second sealing element configured to provide a first gas seal to a swirl gas chamber and defining a portion of the swirl gas chamber; and a third sealing element disposed on the exterior of the body, the third sealing element located between the second sealing element and the second end, the third sealing element configured to provide a second gas seal to the swirl gas chamber and defining a portion of the swirl gas chamber.