Patent ID: 8729423

Claim:
A system for supplying fluids to a plasma arc torch, comprising: a single-gas power supply electrically coupled to the plasma arc torch for regulating supply of electrical power to the plasma arc torch the single-gas power supply coupled to the plasma arc torch via a first supply line for regulating supply of a first fluid to the plasma arc torch; a flow regulator separate from the single-gas power supply and coupled to the plasma arc torch via a second supply line for regulating supply of a second fluid to the plasma arc torch; and a valve assembly comprising: a first valve disposed in the second supply line between the flow regulator and the plasma arc torch, the first valve shutting off supply of the second fluid to the torch when the first valve is closed and allowing the second fluid to be supplied to the torch when the first valve is open, wherein the first valve is configured to be automatically opened to supply the second fluid to the plasma arc torch when the first fluid in the first supply line is sensed to be flowing in the first supply line, and the first valve is configured to be automatically closed when the first fluid is sensed to be not flowing in the first supply line.