DRILL PIPE HARDBAND REMOVAL AND BUILD UP

摘要

A process for plasma arc gouging removal of hardbanding, by a torch (101), from drill pipe (10) rotated by a motorized head stock (30). For plasma arc gouging, electrode stickout is above one inch with substantially constant current power supplies. For plasma gouging the torch parameters that are variable are amps, volts, torch angle, torch height, travel speed, gas flow and stepover. For build up of drill pipe after hardband removal the torch parameters that are variable are wire size, flux and wire type, volts, amps, travel speed, stand off, flux height power supply parameters, pre-heat temperature inter-pass temperature and post weld heat.