High precision shape model and presetting strategy for strip hot rolling

Abstract

The effect of stress release on the shape and deformation of strip between stands are rarely considered or quantified in the traditional strip shape model. In order to make up this deficiency, a high precision shape model is established by the mechanism of the strip shape forming and the deformation of roll system in this paper. Special concentration is placed on the effect of roll wear, roll thermal expansion, metal transverse flow and stress release on the shape. In addition, a tolerance factor which is used to describe the attenuation and tolerance abilities of each stand for longitudinal strain difference is proposed as a foundation for a presetting strategy. Compared to the traditional presetting strategies using the empirical coefficient or Shohet theory, the presetting strategy on the basis of the tolerance factor can better play the control ability of each stand. A systematical description of the presetting strategy and the modeling process of the high precision shape model is given in the present study. The calculated results agree well with experiments, and the actual production data show that the shape model has satisfactory accuracy.