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