Cooling method after rolling

Abstract

The invention discloses a cooling method adopted after steel rolling. The cooling method comprises the steps that 1) finally rolled pipe steel is cooled through jet flow till the surface temperature ranges from 800 DEG C to 850 DEG C; 2) the pipe steel subjected to jet flow cooling stands still for temperature returning till the surface temperature returns to 880 DEG C to 920 DEG C; and 3), afterthe pipe steel subjected to still standing and temperature returning is cooled till the temperature ranges from 800 DEG C to 850 DEG C, the pipe steel is placed under the condition of air cooling to be cooled till the temperature ranges from 400 DEG C to 500 DEG C. The cooling rate in the step 1 ranges from 2.2 DEG C / s to 2.8 DEG C / s. According to the method, the finally rolled pipe steel is firstly subjected to jet flow cooling, then the surface temperature of the pipe steel returns through pipe steel interior temperature conduction, then air cooling is carried out, the banded structure of aSA-210 C high-pressure boiler pipe blank is improved through an after-rolling cooling control technical measure on the premise of not influencing rolling mill production, and then the quality of the manufactured SA-210 C high-pressure boiler pipe blank is improved.

Description

technical field [0001] The invention relates to the field of steel rolling production technology, in particular to a cooling method after steel rolling. Background technique [0002] It is generally believed that the banded structure is mainly caused by component segregation in the steelmaking and continuous casting process. In the prior art, the banded structure is often improved by controlling the continuous casting casting speed, superheat, and adjusting electric stirring. However, the carbon content in SA-210C steel is 0.17-0.23%, and the adjustment measures of the above-mentioned conventional steelmaking process have little effect on improving the banded structure of this steel. In the steel rolling process, controlling the starting rolling temperature and finishing rolling temperature can also improve the band structure, but this process will inevitably affect the production rhythm of the rolling mill, thereby affecting the output of the rolling mill, and will also inc...

AI Technical Summary

Problems solved by technology

While the carbon content in SA-210C steel is 0.17-0.23%, the above-mentioned conventional steelmaking process adjustment measures have little effect on improving the banded structure of this steel

In the steel rolling process, controlling the rolling temperature and finishing temperature can also improve the band structure, but this process will inevitably affect the production rhythm of the rolling mill, thereby affecting the output of the rolling mill, and will also increase the production load of the rolling mill and cause hidden dangers of equipment failure