Edge Drop Control Technology of 4-Hi Tandem Cold Rolling Mill on the Premise of Considering Roll Grinding Accuracy

For gaining strip edge drop controllability and increasing roll grinding precision, the edge drop control work roll (EDW) was developed and designed in 1700 mm tandem cold rolling mill. During the rolling trial, the roll configuration between EDW and conventional backup roll didn’t match well because of the large fluctuation of strip edge drop, the lower shape control ability and non-uniform roll wearing, so the new roll configuration between EDW and varying contact backup roll (VCR) was proposed. After analyzing by finite element model, the result showed that the roll system configuration of VCR and EDW was better by 10.7% larger roll gap crown adjustable scope, 19.1% larger roll gap stiffness characteristics and 21.6% smaller pressure peak between rolls than before. The new roll system configuration has been applied to 1700 tandem cold rolling mill at WISCO after industrial testing.