Method for calibrating empty roll gap of sheet and strip cold-rolling mill

Abstract

The invention provides a method for calibrating the empty roll gaps of a sheet and strip cold-rolling mill. The sheet and strip cold-rolling mill comprises at least two mill frames or a single frame respectively with an upper working roll and a lower working roll which can be adjusted if necessary. The method comprises the following steps: step one: the frame lifts up rolls to the top; step two: the rolls are preliminarily calibrated: opening a roll gap, applying contact rolling force to enable the roll gap to be closed, gradually overlaying delta T1 down-pressing inclination in the direction reverse to the inclination direction of the roll gap, executing step four when the detected rolling force deviation is within the allowable range; executing step three when the inclination direction of the roll gap is changed when being compared with the previous time; and suspending roll calibration when the repeated times exceed the allowable maximum times n max; step three: the rolls are fine calibrated: in the inclination direction of the roll gap, gradually reducing down-pressing inclination delta Ti, wherein the i being more than or equal to 2, the i belongs to N and |delta Ti| being less than |delta T (i-1)|, and executing step four when the detected rolling force deviation is within the allowable range; and step four: roll calibration is ended.

Description

technical field [0001] The invention relates to a steel rolling process, in particular to a roll calibration method for empty roll gaps suitable for tinplate cold rolling mills. Background technique [0002] As one of the most important products of the iron and steel industry, plate and strip play a very important role in the development of the national economy. With the rapid development of modern industry and science and technology, the vast number of users of industrial enterprises have put forward more and more strict requirements on the quality of plates and strips. [0003] The accuracy of steel products mainly refers to the accuracy of the external dimensions of the product. For strip steel, the external dimensions include thickness, width, plate shape, plate convexity, plane shape, etc. Among all the dimensional accuracy indicators, the thickness accuracy is one of the most important quality indicators for measuring plates and strips, and has become a focus of gener...

AI Technical Summary

Problems solved by technology

[0010] The disadvantages of the prior art are: since the thickness of the tinplate is generally less than 0.3mm, the requirements for thickness control are relatively high, and the existing roll calibration method cannot completely eliminate the actual rolling inclination of the roll, so the thickness distribution of the strip along the width direction is uneven. Uniform, there are regular wedge defects in the strip

In addition, due to the serious inclination of the roll system, the oil film bearings often burn out during high-speed operation, resulting in serious strip breakage and piled steel in the rolling mill, which seriously affects the normal production of the rolling mill

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