Cooling method of continuous casting billet solidification processing temperature and quality control

Abstract

The invention relates to a temperature and quality control cooling method in a solidification process of continuous casting billet. The method comprises the following steps: firstly determining a quantitative relation between different continuous casting solidification behaviors of different steel solidification billet shells with temperature range of a secondary cooling low ductility zone, modifying secondary cooling water distribution metallurgical rules and determining a reasonable target surface temperature curve, completing a static control model and a dynamic control model to cause surface temperature of the casting billet to escape from the temperature range of the movable casting billet secondary cooling low ductility zone and fully approach to the target surface temperature. The method can help optimally regulate and control billet shell temperature change in particular the surface temperature change to avoid seaminess which is caused by the move of the secondary cooling low ductility zone (austenite transition temperature range).

Description

technical field [0001] The invention relates to a temperature-controlled cooling method in the solidification process of continuous casting slabs, which is mainly used in the continuous casting cooling process of molten steel, and can also be used in the continuous casting cooling process of non-ferrous metals. The application of this continuous casting process cooling control method can optimally adjust and control the temperature change of the solidification shell in the slab, especially the change of the surface temperature, and formulate a reasonable continuous casting crystallizer and secondary cooling system for steel. It is of great significance to improve the quality of continuous casting slabs, reduce crack defects, especially straighten surface transverse cracks. Background technique [0002] In recent years, my country's continuous casting steel production has continued to maintain a rapid development trend. In 2007, the slab output reached 474.3 million tons, and...

AI Technical Summary

Problems solved by technology

However, no matter which control method is adopted, there are two biggest shortcomings in the static control model: ①The water distribution of each cooling section only changes with the casting speed, and does not consider different continuous casting solidification behaviors (different cooling rates and return temperature rate) on the temperature range (crack sensitive temperature range) of the steel secondary cooling low ductility area; ②The ability to strain under production conditions is poor. When the casting speed changes suddenly, the secondary cooling water distribution also changes suddenly, causing the surface temperature Large fluctuations, prone to crack defects

Therefore, it is obviously not reasonable to formulate cooling water distribution metallurgical criteria based on the fixed temperature range of the secondary cooling low ductility area

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