TMCP steel plate tail plate shape control method

Abstract

The invention discloses a TMCP steel plate tail plate shape control method. The method comprises the following steps that S1, in a heating process stage, tapping temperature and in-furnace time are set according to the thickness of a steel plate; S2, in the rough rolling process stage, the reduction rate, the rolling speed and the accelerated speed of the final pass are controlled; S3, between the rough rolling process stage and the finish rolling process stage, the temperature waiting time of the steel plate is controlled according to the thickness of the steel plate, the rolling starting temperature of the steel plate in the finish rolling process stage is increased, and the temperature waiting time is shortened; S4, in the finish rolling process stage, the reduction rate, the rolling speed and the accelerated speed of the final pass are controlled; and S5, in the MULPIC online cooling process stage, shielding parameters of the tail of the steel plate are set according to the thickness of the steel plate. Through reasonable steel plate heating, rough rolling process, finish rolling process and MULPIC online cooling process, supercooling of the tail plate shape of the steel plate is avoided, the transition uniformity of the tail temperature of the steel plate is improved, the good tail plate shape of the steel plate is obtained after the steel plate is cooled by the MULPIC, and the influence of the poor tail plate shape on the subsequent production efficiency of the steel plate is reduced.

Description

technical field [0001] The invention belongs to the technical field of shape control of a thick TMCP steel plate, and in particular relates to a method for controlling the shape of a tail of a TMCP steel plate. Background technique [0002] TMCP steel plate is a steel plate produced by TMCP technology, which is one of the microstructure control technologies that combine controlled rolling and controlled cooling to obtain excellent properties of steel plate, such as high strength, excellent toughness and weldability, etc. [0003] At present, the Zhanjiang 4200mm production line is vigorously promoting the "replacing gold with water". In the case of adding a small amount of alloy, the high-temperature plate rolled by the finishing mill is cooled by using the online rapid cooling device (MULPIC). The variable method obtains good comprehensive performance. However, there is a phenomenon in the production process. After the steel plate is rolled by the rough and finish rolling ...

AI Technical Summary

Problems solved by technology

However, there is a phenomenon in the production process. After the steel plate is rolled by the rough and finish rolling mills, and the rolled steel plate is cooled by MULPIC according to the flow rate calculated by the model and the speed of the plate, the tail of the steel plate appears bulging, warping, and down. Buckle and other bad phenomena seriously affect the production efficiency of the finishing line

[0004] In terms of controlling the shape of the tail of the steel plate, the existing methods are mainly: 1) MULPIC adopts the method of micro-acceleration, and the conveying speed of the steel plate in the MULPIC is gradually accelerated, so as to avoid the tail of the steel plate being overcooled, thereby affecting the shape of the tail of the steel plate However, the heating system of the steel plate is different due to different batches. Under the influence of the rapid rolling rhythm, the heating uniformity and consistency of the steel plate are poor, which aggravates the difficulty of controlling the shape of the steel plate in rolling, especially the control of the shape of the tail of the steel plate , prone to warping, buckling, etc., which will affect the shape of the plate after online cooling; 2) The MULPIC system has a head and tail shielding function for the head and tail of the steel plate, which is used to cover part of the water volume during cooling of the steel plate to avoid cooling the head and tail of the steel plate If the final temperature is too low, the performance and shape of the steel plate head and tail will be affected, but the parameters set by the model are not conducive to the uniform transition of the cooling temperature of the steel plate tail, which will easily cause uneven cooling of the steel plate tail, resulting in bulging or other bad shape at the steel plate tail

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