the lance pipe 12 and the supporting pipe 46 an expandable chamber 47 is arranged between a flange 52 which is welded to the supporting pipe 46 and a second flange 54 which is welded to the lance pipe 12 an expandable leak proof conduit 56 is attached at one end to flange 52 and at the other end to flange 54 to form chamber 47 fig3 and 4 show a second embodiment of this invention as a fuel air oxygen lance burner the watercooled oxygen lance burner 11 includes an oxygen lance pipe 12 consisting of a watercooled jacket 14 an oxygen nozzle 16 preferably of a laval type and a conduit 18 for delivering oxygen to the nozzle 16 fig5 shows the presence of additional oxygen nozzles 17 for further expelling oxygen from the conduit 18 these additional nozzles 17 should also preferably be of a laval type so that the oxygen is introduced at supersonic velocity during the refining stage these additional nozzles 17 are provided to increase the oxygen flow capacity and the area of molten metal being contacted by the oxygen stream which reduces the duration of the refining cycle and increases overall productivity the oxygen conduit 18 delivers oxygen from the oxygen inlet.