Process for improving ultra-thick head and tail of hot rolling strip steel of Steckel mill

Abstract

The invention discloses a process for improving ultra-thick head and tail of a hot rolling strip steel of a Steckel mill. The process comprises the steps that: an automatic thickness control mode for eliminating the ultra-thick head and tail is added in an automatic thickness control mode of a finishing mill and is adopted in the front three passes of a finish rolling process; when the part is bitten into the strip steel head by less than or equal to 20 meters in the mode, the roll gap is set as 3 to 5 percent less than the normal value; when the part is bitten into the strip steel tail by less than or equal to 30 meters, the roll gap is set as 2 to 3 percent less than the normal value; and moreover, the temperature of the cooling water for a scroll is raised to 70 to 80 DEG C from the normal temperature in order to achieve better improvement effect. The process has the advantages of greatly reducing the ultra-thick degree of the head and the tail, shortening the ultra-thick length and improving the hot rolling casting yield through the temperature change of the cooling water for the scroll and the addition of the thickness control mode.

Description

technical field [0001] The invention relates to a process for improving the thickness deviation of strip steel, in particular to a process for improving the overthickness of the head and tail of hot-rolled strip steel in a steckel mill. Background technique [0002] Steckel rolling mill is to install two coil furnaces with reel and burner, as well as coiling and heating functions, on both sides of the inlet and outlet of the finishing mill, so as to ensure that the temperature of the strip steel during the rolling process is maintained or the temperature is not too high. The drop is too large. During the rolling process of hot-rolled strip steel, since the head and tail have the largest contact area with the outside world, the temperature drops the fastest. In addition, because the head and tail of the strip steel are in direct contact with the reel in the coil furnace (the reel is cooled by cooling water at room temperature), so There is a temperature difference with the c...

AI Technical Summary

Problems solved by technology

In addition, in order to obtain a better improvement effect, the cooling water of the reel is increased from normal temperature to 70-80°C, and the temperature drop will be further slowed down when the head and tail of the strip are in direct contact with the reel during the coiling process, further improving the thickness of the head and tail. Defects