High-grade pipeline steel finish rolling temperature stability control method

Abstract

The invention discloses a high-grade pipeline steel finish rolling temperature stability control method. The method comprises the following steps that pipeline steel is heated; rough rolling is carried out on the heated pipeline steel; finish rolling is carried out on the pipeline steel subjected to rough rolling; finish rolling of the pipeline steel after rough rolling comprises the steps that finish rolling is carried out on the pipeline steel at a constant speed; and cooling water is started for a first rack and a fourth rack in a finish rolling rack set, and after a seventh rack bites thesteel for preset time, the cooling water is stopped. According to the high-grade pipeline steel finish rolling temperature stability control method, finish rolling is carried out at a constant speed to improve the stability of the finish rolling temperature, the cooling water between the F1 rack and the F4 rack is adopted, the strip steel head finish rolling temperature is reduced by adding waterto the F4 rack at the head, so that the purpose of stabilizing the overall finish rolling temperature is achieved.

Description

technical field [0001] The invention relates to the field of rolling control methods, in particular to a method for stabilizing the final rolling temperature of high-grade pipeline steel. Background technique [0002] The main function of pipeline steel is to undertake the transportation of oil and gas after becoming steel pipes through spiral submerged arc welding or straight seam submerged arc welding. With the advancement of national key projects such as West-to-East Gas Transmission and Sichuan-to-East Gas Transmission, the demand for pipeline steel is increasing day by day , especially high-grade pipeline steel represented by X80. Since the X80 pipeline steel has extremely high requirements on comprehensive properties such as strength, hardness and impact toughness, it has extremely high requirements on the uniformity of the final rolling temperature of the strip. [0003] In the prior art, there are mainly two strategies for controlling the finish rolling temperature ...

AI Technical Summary

Problems solved by technology

For example, a company’s 2050mm hot rolling line uses speed and acceleration to control the final rolling temperature. For conventional varieties, the final rolling temperature of the strip can be controlled at ±20°C, but the temperature difference between the head and the tail of the high-grade pipeline steel is >20°C. ℃, leading to a large difference in head-to-tail performance, which needs to be controlled and treated

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