A non-sequential isothermal local-loading forming process for large-scale rib-web components

Abstract

In order to solve the problem of deformation and warpage of large-scale rib-web components by the local-loading method, we propose a new non-sequential isothermal local-loading (NSILL) forming method. First, we design the forming die and then establish a finite element (FE) model of the new NSILL forming method. The reliability of the FE model is evaluated by comparing the load-time curve and warping effect. We introduce the bending angle and extension length of the billet to comprehensively evaluate its formability. Our research found that the larger top die length, the larger the bending angle and the smaller the metal extension length. In addition, we compare these two indexes of three typical loading sequences of NSILL forming, and find that sequential loading from left to right can improve bending angle, meanwhile loading successively from both sides to the middle can reduce metal extension. We therefore propose a multiple-region control non-sequential local-loading forming method. This novel method can achieve better deformation compatibility for forming LSRW components with bending angle changed from 155.11° to 179.81° and metal extension length decreased from 89.55 mm to 0 mm, and the maximum forming load was reduced with a reduction rate of 19.24%.