摘要 |
A torch assembly for TIG relaxing an inner surface of a tube to be removed from a tube sheet which comprises a conductive base containing passages for cooling water and for inert gas. A sheath is rotatably mounted to the base and contains a drive shaft fixed to the base. A torch head is fixed to an opposite end of the drive shaft and the drive shaft is embraced by a conductive braid so that electrical power applied to the base is conveyed to the torch head. A torch tip extends radially from the torch head and is used to strike an arc with the inner surface of the tube to be TIG relaxed. Inert gas is supplied through the sheath and to a space around the head which is confined by a gas cap. A hole in the gas cap receives the end of the torch tip so that inert gas bathes the annular space around the tip to protect the arc.
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