Method for rolling wide and thick steel plate by adopting complete negative allowance

Abstract

The invention discloses a method for rolling a wide and thick steel plate by adopting a complete negative allowance. The method is used for thickness compensation in the length direction of the steel plate on the basis of an automatic thickness control system, so that the allowance of the whole steel plate containing the head and the tail of the steel plate is controlled between minus 0.3 mm and 0 mm. The main thickness compensation parameters are as follows: when X=400-800, T'=0.2; when X=200-400, T'=0.3-(0.3*400) / X; and when Y=200-400, T'=0.5-(0.5*400) / X. The thickness allowance of the wide and thick plate rolled by adopting the method is controlled within the range of minus 0.3-0mm, and the percent of pass is not less than 90%, therefore, the lumber recovery of the steel plate and the thickness uniformity of the whole plate can be effectively improved, the cost of steel per ton can be reduced, and the load capacity can be improved.

Description

technical field [0001] The invention belongs to a steel rolling method, in particular to a method for rolling a wide and thick steel plate with a complete negative tolerance. technical background [0002] Negative tolerance rolling of steel plate is an advanced rolling process. The thickness of the finished product is slightly smaller than the thickness of the steel plate order, and it is controlled within the negative tolerance range of the national standard or enterprise standard. This rolling method can not only improve the product yield (the weight of the plate is calculated according to the size), but also meet the special customer requirements. For example, when used in shipbuilding, the self-weight can be reduced under the premise of ensuring the strength, which is helpful for reducing rolling costs and improving brand effect. All can have an immediate effect. However, due to the small tolerance range of the steel plate, it is a huge test and challenge for the precis...

AI Technical Summary

Problems solved by technology

[0004] Due to the above reasons, the thickness tolerance range of the steel plate is relatively large, about -0.3~+1.0mm. The automatic thickness control system (AGC) in the existing technology can overcome the influence of the fluctuation of the steel plate process parameters on the thickness, but it cannot affect the thickness of the steel plate head and tail. Control its thickness within the range of -0.3~0mm, because the temperature drop of the steel plate head is fast, the rolling force rises, the actual rolling force is greater than the set rolling force, and the rolling thickness occurs, so that the thickness tolerance is greater than 0mm; when AGC After the system is self-adapted, the actual rolling force will drop, and rolling thinning will occur, and the thickness tolerance will be less than -0.3mm; the temperature drop at the tail of the steel plate is fast, but because it is the tail, the time is short, only the rolling force drops, making the thickness Tolerance is less than -0.3mm

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