{HEAD ~ This feedback system} keeps {TAIL ~ the heat} of the welding process at a given selected and desired level 
{ HEAD ~ This feedback system } keeps { TAIL ~ the heat } of the welding process at a given selected and desired level
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH