Method and device for controlling casting roll force and roll gap in thin strip continuous casting

Abstract

The present application discloses a method and device for controlling the casting rolling force and roll gap of casting rolls in thin strip continuous casting, which relate to the field of metallurgical technology and can solve the current problems in controlling the casting rolling force and roll gap of casting rolls in thin strip continuous casting. , resulting in poor product production stability, and prone to serious cracks or even broken technical problems. The method includes: calculating the target rolling force of the casting roll according to the rolling force calculation equation; calculating the basic roll gap of the casting roll according to the rolling mill bounce equation; using the double-layer structure roll gap PID controller, based on the casting roll basic roll gap The roll gap in continuous casting is fine-tuned to match the actual casting force of the casting roll with the target rolling force of the casting roll. It can automatically control the roll gap and the casting force according to the different conditions of the equipment in different time periods and the thickness of the casting strip, so as to achieve stable casting, ensure the effect of strip formation, and minimize the fluctuation of relevant parameters of the casting roll. The purpose of forming strips and improving the quality of cast strips.

Description

technical field [0001] The application relates to the field of metallurgical technology, and in particular, to a method and device for controlling the casting rolling force and roll gap of casting rolls in thin strip continuous casting. Background technique [0002] The process of thin strip continuous casting has its particularity. While the casting rolls solidify the molten steel, the casting rolls need to roll the solidified original shell to a certain extent, and the rolling process should be uniform and relatively small along the roll gap direction. The casting and rolling force is evenly distributed in the direction of the roll gap, and the thickness distribution of the original shell obtained by solidification needs to match the roll gap of the casting roll, and the appropriate casting and rolling force to be applied to the whole cast strip needs to be carried out according to factors such as the state of the equipment and the thickness of the cast strip. Considering...

AI Technical Summary

Problems solved by technology

If the casting and rolling force exerted by the casting roll on the cast strip is too small, it is easy to cause too much liquid phase structure in the center of the cast strip. After the cast strip leaves the casting roll, the liquid phase structure will reheat the columnar crystal part in the slab shell, reducing the mechanical strength of the cast strip. , it is easy to break the belt, and once the belt breaks, it will seriously affect the production rhythm and the specifications of the finished steel coil, and even cause production interruption

Excessive casting and rolling force applied to the cast strip will amplify the impact of mechanical equipment design and manufacturing errors on the casting strip from a macro perspective, resulting in excessive fluctuations in casting and rolling force, which in turn will cause fluctuations in the thickness of the cast strip, affecting product quality and subsequent hot rolling and Cold rolling process; microscopically, it will cause microcracks on the surface of the cast strip. The existence of microcracks will seriously affect the mechanical strength of the product, and even directly cause strip breakage in the subsequent hot rolling or cold rolling production process.

[0004] In the initial stage of strip continuous casting production, since the thermal balance relationship among molten steel, casting rolls and casting roll cooling water has not been fully established, and the parameters of the equipment have not fully entered the stable state, it is often necessary to use a slightly larger Casting roll reduction. In the existing technology, the adjustment of casting roll reduction is often done manually by operators based on on-site experience. Manual adjustment will inevitably lead to excessive adjustment range in a short period of time and inaccurate adjustment. Reaction lag and other problems cause fluctuations in equipment parameters and affect the stability of continuous production

Once the operator makes a wrong judgment, it is easy to cause parameter adjustment errors, product quality changes, and even serious problems such as broken belts.

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