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