Analysis and simulation of spring-back in the production of variable radius shell by roll bending process

In this paper, the amount of spring-back after 3- roll bending and the effect of different factors such as friction, lateral roller position, roll speed, and thickness reduction percentage of rolling sheet prior to bending on the spring back ratio of aluminum alloy sheet in ambient temperature have been investigated. For this purpose, simulation and finite element roll forming model is done by ABAQUS. In order to validate, a comparison between simulation data and experimental results was performed. To obtain the equation for precise prediction of the values of bending radius after spring-back using SPSS software, regression analysis of the radius values after the spring return obtained from finite element simulation has been studied. Then, the effects of factors affecting bending radius and spring-back ratio have been discussed. The results show that with the method presented in this paper precise prediction of the effect of roll bending parameters changes on spring-back ratio can be obtained. In the following, this technique is used to produce shells with two different curvatures. This method can be a very suitable alternative for bending in the mold or stretch forming in the production of a weld shell and the body of the aircraft.