A device and method for removing liquid steel inclusions in a tundish of a double-strand slab continuous caster

Abstract

The invention relates to a device for removing molten steel slag inclusion in a tundish of a double-flow slab caster. A first blocking dam, a second blocking dam and parapets are arranged between one tundish water supply port and a turbulence controller at intervals in sequence in a parallel mode, the height of the second blocking dam is larger than that of the first blocking dam, and air curtain ventilation bricks (4) are symmetrically arranged between the turbulence controller and the parapets on the two sides of the turbulence controller and are arranged outside the turbulence controller in a V shape. By means of the device, the slag inclusion with the equivalent diameter larger than 50 microns in a continuous casting is completely removed, and the amount of the slag inclusion with the equivalent diameter smaller than 50 microns in the continuous casting is reduced by more than 50 percent compared with the amount of the slag inclusion in a continuous casting produced through the double-flow slab caster tundish internally provided with the turbulence controller, the parapets and the blocking dams and is reduced by more than 30 percent compared with the amount of the slag inclusion in a continuous casting produced through the double-flow slab caster tundish purely and internally provided with the turbulence controller and the air curtain ventilation device.

Description

technical field [0001] The invention relates to a device and method for removing liquid steel inclusions in a tundish of a double-strand slab continuous casting machine, and belongs to the technical field of iron and steel metallurgy continuous casting tundish technology. Background technique [0002] As the metallurgical reactor between the ladle and the crystallizer, the continuous casting tundish has developed from the initial basic functions of decompression, steady flow, steel storage and flow diversion to a role of promoting The metallurgical function of floating and separating inclusions, preventing secondary oxidation of molten steel, controlling the shape of inclusions and microalloying molten steel. [0003] Generally, the tundish of a double-strand slab continuous casting machine includes a tundish body, which is provided with a turbulence controller, and the bottom of the tundish is provided with two tundish nozzles, and the turbulence controller is arranged betw...

AI Technical Summary

Problems solved by technology

[0006] In the actual production process, after long-term production practice, it has been proved that the existing flow control device and the continuous casting tundish air curtain retaining wall technology have technical defects: (1) The tundish of the continuous casting machine is set by The combination of turbulence controller, retaining wall and retaining dam can only effectively remove inclusions with an equivalent diameter greater than 50 μm, but cannot effectively remove tiny inclusions with an equivalent diameter less than 50 μm, even if the equivalent diameter can be removed. Inclusions with a diameter greater than 50 μm cannot be completely removed; the technical scheme of setting air curtain permeable bricks in the tundish of the continuous casting machine can only effectively remove tiny inclusions with an equivalent diameter of less than 50 μm, but cannot effectively remove the equivalent diameter greater than 50μm inclusions, and the removal effect of tiny inclusions with an equivalent diameter less than 50μm is not ideal; (2) The installation position of the existing air curtain ventilation brick has technical defects: the existing air curtain ventilation brick replaces the dam or is installed on the dam In the pouring area between the dam and the upper nozzle of the tundish, the actual application effect of effectively removing tiny inclusions with an equivalent diameter of less than 50 μm is poor; (3) In order to remove the effect of inclusions in molten steel, air curtain permeable bricks are required to produce air bubbles The diameter is small and the density is high, but the slit-type air curtain permeable bricks produced by the existing technology have large pores, generally the equivalent diameter is greater than 50 μm, and the equivalent diameter of the generated bubbles is relatively large (measured by the water model experiment, the equivalent diameter of the bubbles is greater than 1.5mm) and the number is small, the density of air bubbles forming the air curtain retaining wall is small, so the practical application effect of removing inclusions is not ideal; (4) Technical defects after the retaining wall is installed in the tundish of the double-strand slab continuous casting machine : In the impact area between two symmetrically installed retaining walls, firstly, the steel slag floating on the liquid surface in the impact area cannot be regularly discharged through the overflow port, and secondly, the tundish covering agent added in the impact area cannot be The flow of steel slag achieves uniform coverage of the steel slag surface, which in turn causes molten steel to be exposed and secondary oxidation, resulting in new inclusions

However, this patent has the following disadvantages. Although the upper retaining wall and the lower retaining wall can remove a part of the inclusions with an equivalent diameter greater than 50 μm, the removal effect is not ideal, and the pores of the air curtain permeable brick are large, and the diameter of the argon bubbles produced is relatively large. Rare, the removal of inclusions with an equivalent diameter greater than 50 μm and inclusions with an equivalent diameter less than 50 μm is not ideal

Images