METAL SMELTING ASSEMBLY Russian patent published in 1998 - IPC

FIELD: metallurgy. SUBSTANCE: invention, in particular, relates to structure of converters of electric furnace and other smelting assemblies with neutral gas blasting from below to increase stability of lances for bottom blasting of neutral gas through metal. Assembly includes casing, reinforcement and working layers of refractory linen, bottom blast lances installed in the bottom of assembly and consisting of two coaxially arranged tubes forming annulus where strengthening ribs are disposed, the latter being made in the form of multithread screw guides confining channels. Between ribs and inside surface of external tube, there is a slot 0.1- 0.3 the size of annulus. Length of screw guides along height of lance constitutes 0.4-0.7 thickness of working layer of linen on the bottom of assembly. On the surface of ribs, lengthwise, discrete arresters are available to center internal tube of lance with respect to external one. Size of slot between ribs is variable along length of lance and increases toward its end by 10-50% as compared to its initial size. Slots are also made on the side of external and internal tubes. EFFECT: increased durability of lances and reduced gas consumption. 4 cl, 4 dwg , 1 tbl