Theory and Technology of Transverse Thickness Deviation Control for DI Tinplate during Tandem Cold Rolling

Abstract

In order to study the transverse thickness deviation's generation and control of soft, wide, thin steel strip in tandem cold rolling process, which is described by crown and edge drop, the integrated simulation model of rolls and strip is established based on the finite element software ABAQUS. The index of transverse thickness deviation control weight is defined, that is used to reflect the importance of each stand of cold rolling mill to control transverse thickness deviation of finished strip. The law of generation and inheritance of transverse thickness deviation and the coupling effects of crown and edge drop are deeply researched. The control strategy of transverse thickness deviation for soft and thin strip and control technology transverse thickness deviation for DI tinplate in tandem cold rolling process are explored and studied. Simulation results have shown that the weight of first two stands is much higher than other stands in tandem cold rolling mill. They are the most suitable and most effective stands for transverse thickness deviation control. Generally, the weight of stand 1 is larger than stand 2. But when the strip material is softer and the thickness is thinner, the weight of stand 2 could exceed stand 1. The coupling degree of edge drop and crown at each stand gradually improve in the rolling process from stand 1 to stand 5. Combined with the simulation analysis results, the overall strategy and series technologies are proposed for transverse thickness deviation control of DI tinplate at a 1420 tandem cold rolling mill, which are put into long-term and stable use after production testing. The production data show that the qualified rate of DI tinplate transverse thickness deviation control precision is improved from 76.25% to 92.10%.1