Double-hole immersed waterslot for flexible thin slab casting (FTSC) crystallizer

Abstract

The invention relates to the field of waterslot of metallurgical continuous casting equipment, in particular to a double-hole immersed waterslot for an FTSC crystallizer, which comprises an upper molten steel inflow end, a middle runner and a lower outflow end, which are connected in turn, wherein the lower inflow end is provided with outlet holes which are symmetric on two sides, and sub fluid flows between the outlet holes. The double-hole immersed waterslot for the FTSC crystallizer is characterized in that: two outlet holes are formed; the inclination angle of the outlet holes is 11 to 13DEG; the height H of the outlet holes is 133 to 138 millimeters; and the width d of the outlet holes is 27 to 28 millimeters. Compared with the prior art, the double-hole immersed waterslot for the FTSC crystallizer has the advantages that: 1) the flowing of molten steel around the waterslot is promoted, and the solidifying blank shell is prevented from being adhered with the waterslot; 2) the nonmetallic impurities in molten steel can float up easily to be absorbed by protective slag and thus removed; 3) the phenomenon that slag is carried on the surface of the molten steel in a crystallizeris avoided; and 4) the molten steel can solidify easily to form initial crystal blank shell with uniform thickness around, and consequently the surface quality of the thin plate blank can be ensured.

Description

technical field [0001] The invention relates to the field of metallurgical continuous casting equipment nozzles, in particular to a two-hole submerged nozzle for FTSC thin slab continuous casting crystallizers. Background technique [0002] The thickness of the slab produced by the Flexible Thin Slab Caster (FTSC) thin slab continuous casting developed by Danieli in Italy is generally between 65 and 92 mm, and the width is about 900 to 1650 mm. The FTSC thin slab continuous casting machine is different from the flat plate mold commonly used in conventional slab continuous casting machines. The mold of the FTSC thin slab continuous casting machine is similar to the CSP thin slab continuous casting machine. The wide copper plate has a continuous arc The surface formed by the transition, the entire crystallizer is "funnel-shaped", but the "funnel" of the two crystallizers is different in size. The increase in the upper space of the molten steel pool in the funnel-shaped crysta...

AI Technical Summary

Problems solved by technology

[0005] According to the above research and understanding of the molten steel movement behavior in the molten pool in the FTSC thin slab continuous casting mold, at present, the submerged nozzles used in the production of FTSC thin slab continuous casting machine molds at home and abroad mostly adopt four-hole flat nozzles (see attached Image 6 ), the four-hole submerged nozzle directly transports the high-temperature molten steel to the liquid surface of the molten pool around the nozzle through two upward spit holes (9), which better realizes the upward movement of the high temperature zone of the molten steel in the molten pool, but due to the upper spit hole The molten steel jet is basically vertically upward, which has a serious impact on the liquid surface of the molten steel pool of the mold, and the high temperature area of ​​the molten steel surface in the molten pool is only concentrated around the nozzle, making the temperature distribution of the entire molten steel surface uneven

attached Figure 7 The shown is an improved four-hole submerged nozzle, and the liquid steel jet flowing out substantially horizontally formed by the upper upward spout hole (9) suppresses the circulation flow in the mold caused by the downward spit hole (10) molten steel jet. , so that the liquid level of the molten pool is relatively stable, but at the same time it also causes the negative effect of non-metallic inclusions floating up, so it is not suitable for continuous casting production of varieties of steel that require high billet cleanliness

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