Abstract: Precise plate shape control theory is significant to improve rolled strip quality, and roll flattening theory is a primary part of the plate shape theory. To improve the accuracy of roll flattening calculation based on semi-infinite body model, a new and more accurate roll flattening model is proposed, which is derived basing on boundary integral equation method. The lateral surface displacement field of the finite length semi-infinite body is simulated by using finite element method(FEM) and lateral surface displacement decay functions are established. Based on the new roll flattening model, a new 6-Hi mill deformation model is established and verified by FEM. The new model is compared with Foppl formula and semi-infinite body model in different plate width, roll shifting value. The results show that the pressure and flattening between rolls calculated by the new model are more precise than other two models, especially near the two roll barrel edges.

Key words: 6-Hi mill, Boundary integral equations, Finite element method, Finite length semi-infinite body, Roll deformation