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