{HEAD ~ Air} is conveyed onto {TAIL ~ the engraving work surface} to cool the workpiece and reduce the possibility of fire 
is conveyed onto
{ HEAD ~ Air } is conveyed onto { TAIL ~ the engraving work surface } to cool the workpiece and reduce the possibility of fire
HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH