Cold roll forming is a high production but complex metal forming process under the conditions of coupled effects with multi-factor. A new booting finite element method (FEM) model using the updated Lagrangian (IAL) method for multistand roll forming process is developed and validated. Compared with most of the literatures related to roll forming simulation, the new model can take the roll rotation into account and is well suited for simulating multistand roll forming. Based on the model, the process of a channel section with outer edge formed with twelve passes is simulated and the sensitivity analysis of parameters is conducted with orthogonal design combined FEM model. It is found that the multistand roll forming process can be efficiently analyzed by the new booting model, and sensitivity analysis shows that the yield strength plays an important role in controlling the quality of the products.
Five-axis NC machining provides a valid and efficient way to manufacture the mechanical parts with complex shapes,which are widely used in aerospace,energy and national defense industries. Its technology innovations have attracted much attention in recent years. In this paper,the state-of-the-art techniques for five-axis machining process planning are summarized and the challenging problems are analyzed from the perspectives of tool path generation,integrated geometric/mechanistic simulation and machining stability analysis. The recent progresses in accessibility-based tool orientation optimization,cutter location (CL) planning for line contact and three-order point contact machining,shape control of cutter envelope surface and milling stability prediction are introduced in detail. Finally,the emerging trends and future challenges are briefly discussed.