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