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