A casting furnace is fed an inert gas under {HEAD ~ pressure} through {TAIL ~ a feed line} with the pressure being regulated by a melt level control device 
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A casting furnace is fed an inert gas under { HEAD ~ pressure } through { TAIL ~ a feed line } with the pressure being regulated by a melt level control device
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH