Umbrella-type submersed nozzle of crystallizer for continuous-cast round billets

Abstract

The invention discloses an umbrella-type submersed nozzle of a crystallizer for continuous-cast round billets. The umbrella-type submersed nozzle comprises a nozzle side wall with an inner hole formed in the upper portion, a concave bottom plate with the lower portion closed, at least one side support hanging column for connecting the nozzle side wall and the concave bottom plate into a whole, and a lateral outlet arranged on the lower portion of the nozzle side wall. The lateral outlet is an annular outlet penetrating through the circumferential side wall of the whole nozzle, and the annular outlet inclines downward by an angle of alpha and is shaped like an umbrella. Molten steel can be injected in through the inner hole of the nozzle side wall and evenly flows out of the lateral outlet in the circumferential direction. Compared with the prior art, the umbrella-type submersed nozzle has the advantages that green billet shells will not be scoured or damaged, and thus the thickness of the billet shells is uniform in the circumferential direction; the flow field of the molten steel in the crystallizer is reasonable in distribution, an upper ring flow and a lower ring flow are formed in the upper flow field of the crystallizer, and thus casting powder can be molten easily; the impact depth of the molten steel is small, and thus gas and inclusions can float up easily. The superiority of the umbrella-type submersed nozzle can be better played for continuous cast of round billets with the diameter of the fracture surfaces of the cast billets larger than 400 mm.

Description

technical field [0001] The invention belongs to the field of continuous steel casting, in particular to a submerged casting nozzle device for a round billet continuous casting crystallizer. Background technique [0002] The submerged nozzle of the continuous casting mold is a device widely used in the continuous casting process. Its main function is to prevent the secondary oxidation and splashing of the molten steel during the process of injecting the molten steel from the tundish into the continuous casting mold. Control and adjust the flow field and temperature field of the molten steel in the crystallizer to make the molten steel solidify reasonably and effectively float the gas and non-metallic inclusions in the molten steel. The submerged nozzle of the crystallizer can improve the quality of the cast slab, facilitate the casting with mold slag, and make the continuous casting operation stable. It is widely used in continuous casting of steel. The influence of the subm...

AI Technical Summary

Problems solved by technology

Although this nozzle reduces the scour degree of the steel flow on a certain part of the primary shell, but along the height direction of the crystallizer, the scour range of the primary shell will increase, and the flow field and temperature field in the circumferential direction will increase. equally uneven distribution

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