English to Portuguese Tech/Engineering Metallurgy / Casting Welding

This term appears isolated in a drawing and I found the following definition in English:
"Backgouging is a term used in welding to designate one operation consisting in grinding the root pass from the back side to sound metal and then finishing the weld by the back side.
It's a normal practice for two side weldings. It's also common to assure good weld penetration in "almost" one side welds (for example Vee weld end preparation) if the back side is reachable (welding plates or high diameter pipes)."