A brazing oven includes an arrangement employing {HEAD ~ a gas curtain} or barrier to cover the port or {TAIL ~ opening} of the oven whenever the door is opened 
A brazing oven includes an arrangement employing { HEAD ~ a gas curtain } or barrier to cover the port or { TAIL ~ opening } of the oven whenever the door is opened
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH