Method for controlling shape of thick steel plate with thickness greater than 50mm

Abstract

The invention discloses a method for controlling the shape of a thick steel plate with the thickness greater than 50mm. A continuously cast bloom with the thickness of 250mm or 300mm is selected, the tapping temperature of a plate blank is 1150-1230 DEG C, the rolling temperature is 1140-1220 DEG C, a steel plate is rolled in a controlled manner in two stages, the rolling speed in the first stage is 1.1m / s, and the single-pass compression rate is greater than or equal to 10%; the rolling thickness of a second stage is 1.2-3.5 times the thickness of a finished product of the steel plate, and the rolling temperature in the second stage is 880-940 DEG C; in the second stage, the steel plate is rolled by 4-7 passes, the rolling speed of each pass is 2-3.5m / s, the compression rate of the final three passes in the second stage is controlled in a range between 1.5%-8%, and the final rolling temperature is controlled in a range between 850 DEG C and 870 DEG C; and after rolling in the second stage is finished, the steel plate is straightened via a thermal straightener after being cooled via ACC (activated calcium carbonate), the straightening temperature is greater than 400 DEG C, and the straightening force is controlled in a range between 6000KN-12000KN.

Description

technical field [0001] The invention relates to a technology for controlling the flatness of thick steel plates during the production of wide and thick plates in the field of steel rolling, in particular to a technology. Background technique [0002] Due to the development of controlled rolling and controlled cooling technology, thick steel plates are generally produced by controlled rolling and controlled cooling technology. [0003] The production process of medium and heavy plates is usually combined with controlled rolling, and the heating system of the slab being released from the furnace at a lower temperature is adopted. On the one hand, it can reduce energy consumption and fuel consumption, and on the other hand, it can make the original austenite grains of the slab fine , which is beneficial to the toughness of the finished steel plate. Rolling adopts two-sequence or three-sequence rolling. The three-sequence rolling method is: [0004] ① Forming rolling: improve...

AI Technical Summary

Problems solved by technology

This method cannot completely eliminate the wave shape of the steel plate because there is no reduction in the final pass; and since only the upper and lower rolls are in contact with the steel plate in the rolling mill, there is no reduction in the final pass, which cannot eliminate the warping produced by the previous rolling pass , kowtow and other plate shape defects