Refractory coated oxygen lance

Claim 1

AN OXYGEN LANCE HAVING AN OUTLET END ADAPTED TO BE IMMERSED IN A BATH OF MOLTEN STEEL FOR INJECTING OXYGEN OR OTHER GAS INTO THE BATH, SAID LANCE COMPRISING: A SHORT LENGTH OF METAL PIPE HAVING A RELATIVELY THICK WALL HAVING SUFFICIENT BENDING STRENGTH TO SUPPORT ITSELF WITHIN A STEEL FURNACE WITHOUT BENDING, SAID PIPE BEING ADAPTED TO BE COUPLED TO A GAS LINE FOR FEEDING GAS TO SAID LANCE; AN ELONGATED LENGTH OF METAL TUBING HAVING A RELATIVELY THIN WALL, RELATIVE TO SAID PIPE, FIXED END-TOEND TO SAID PIPE AND IN AXIAL ALIGNMENT WITH SAID PIPE, SAID TUBING SERVING AS THE OUTLET END OF SAID LANCE; AND A HEAT-RESISTING INSULATING REFRACTORY COATING COVERING SAID LENGTH OF TUBING AND THE END PORTION OF SAID PIPE ADJACENT TO SAID TUBING, SAID REFRACTORY COATING BEING SEVERAL TIMES AS THICK AS SAID TUBING TO REINFORCE SAID TUBING SUFFICIENTLY TO PREVENT ITS BENDING WHEN THE LANCE IS USED IN A STEEL FURNACE AND TO SUBSTANTIALLY PROTECT SAID TUBING FROM THE HEAT OF THE STEEL FURNACE, THE OTHER END PORTION OF SAID PIPE BEING FREE OF SAID REFRECTORY COATING FOR COUPLING SAID LANCE TO A GAS LINE; SAID TUBING BEING SUFFICIENTLY THIN WHEN EXPANDED BY THE HEAT OF A STEEL FURNACE TO YIELD WITHOUT BREAKING SAID REFRACTORY COATING AND BEING OF AN INSUFFICIENT THICKNESS TO BE THREADED.