GASUFUKIKOMIGATACHUZOYONOZURU

摘要

PURPOSE:To effectively prevent gas leakage that may occur near the fitting part of a gas blowing pipe which supplies gas to a nozzle hole by screwing and inserting said gas blowing pipe via stainless steel pipe into the nozzle hole provided to a nozzle body. CONSTITUTION:An annular gases pressure equalizing zone 14 is provided longitudinally within the body 11 of a nozzle hole 13 having a discharge port 12 in proximity to the hole 13. A screwed hole 15 communicating the zone 14 and the outside is provided to the side wall at the top end of the body 11. A stainless steel pipe 16 having long spaces of the screw thread pitches of the outside circumferential surface and short spaces of the screw thread pitches of the inside circumferential surface is screwed into this hole 15 by way of an inorg. adhesive layer 17. Further, a gas blowing pipe 18 cut with screw threads at the leading end is screwed and inserted into the pipe 16. Thereby, the stresses accompanied with the difference in thermal expansion between the pipe 18 and the nozzle body 11 made of refractories owing to the thermal influence during pouring of molten steel are relieved by the pipe 16 between these.