A tundish free injection long nozzle structure and argon blowing smelting method

Abstract

The invention relates to a tundish free injection shroud structure, which comprises an upper pipe section and a lower pipe section, respectively forming pipe holes inside, and the pipe holes of the upper pipe section communicate with the pipe holes of the lower pipe section; the inner diameter of the pipe holes of the lower pipe section is larger than The inner diameter of the pipe hole of the upper pipe section is provided with an air hole on the lower pipe section, and the air hole is connected with the pipe hole inside the lower pipe section. The invention divides the traditional ladle shroud into a thinner upper pipe section and a thicker lower pipe section. The inner top surface of the lower pipe section is higher than the molten steel by a certain distance, forming an argon suction space between the lower pipe section and the liquid steel surface. After the molten steel flows out from the upper pipe section, it forms a free injection flow under gravity, and the argon gas in the argon suction space is entrained into the molten steel to form tiny argon bubbles, and the argon suction space relies on negative pressure to replenish argon by itself. The invention can not only suppress the increase of bubbles caused by non-wet conditions during the argon blowing process of the nozzle, but also avoid the blockage of the pores during the argon blowing process, the device is easy to maintain, and the molten steel can be realized at a lower cost. Deep cleansing.

Description

technical field [0001] The invention relates to the field of iron and steel metallurgy, in particular to a continuous casting tundish free injection shroud structure applied to clean steel smelting and an argon blowing smelting method using the shroud. Background technique [0002] At this stage, the steel industry is facing the dilemma of "overcapacity at the low end and insufficient production capacity at the high end". Under the increasingly stringent environmental pressure, improving the performance of steel and adjusting the product structure are the only way for the sustainable and healthy development of steel enterprises. At present, the number and maximum size of inclusions contained in some high value-added steel products should meet strict requirements. Therefore, minimizing the size and quantity of inclusions in steel and realizing the smelting of clean steel with high efficiency and low cost is an important way to improve product quality and increase the profita...

AI Technical Summary

Problems solved by technology

The improvement of the shroud in the existing technology is basically focused on reducing the impact on the tundish, preventing the pouring splash, improving the safety of the pouring, etc., and seldom designed from the aspect of improving the cleanliness of the molten steel; while the argon blowing smelting The process needs to continuously provide a source of argon gas with a certain pressure to the molten steel, resulting in high energy consumption and maintenance costs

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