Bending analysis and control of rolled plate during snake hot rolling

ZHANG Tao(张涛)^{1, 2}, WU Yun-xin(吴运新)^{1, 2}, GONG Hai(龚海)^{1, 2, 3}, ZHENG Xi-zhao(郑细昭)^{1, 2}, JIANG Shao-song(蒋绍松)^{1, 2}

(1. State Key Laboratory of High Performance Complex Manufacturing (Central South University),
Changsha 410083, China;
2. School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China;
3. School of Materials Science and Engineering, Central South University, Changsha 410083, China)

Abstract:In order to study the bending behavior of aluminum alloy 7050 thick plate during snake hot rolling, several coupled thermo-mechanical finite element (FE) models were established. Effects of different initial thicknesses, pass reductions, speed ratios and offset distances on the bending value of the plate were analyzed. ‘Quasi smooth plate’ and optimum offset distance were defined and quasi smooth plate could be acquired by adjusting offset distance, and then bending control equation was fitted. The results show that bending value of the plate as well as the extent of the increase grows with the increase of pass reduction and decrease of initial thickness; the bending value firstly increases and then keeps steady with the ascending speed ratio; the bending value can be reduced by enlarging the offset distance. The optimum offset distance varies for different rolling parameters and it is augmented with the increase of pass reduction and speed ratio and the decrease of initial thickness. A proper offset distance for different rolling parameters can be calculated by the bending control equation and this equation can be a guidance to acquire a quasi smooth plate. The FEM results agree well with experimental results.

Key words:snake hot rolling; bending analysis; quasi smooth plate; optimum offset distance; bending control equation