The electrical welding device adds material to the inside of the valve body by using {HEAD ~ an electrode} to provide {TAIL ~ an arc} 
to provide
The electrical welding device adds material to the inside of the valve body by using { HEAD ~ an electrode } to provide { TAIL ~ an arc }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL