CONTINUOS MULTIPLE-PRESS BENDING PROCESS APPLICABLE FOR CURVED SHELL PLATES IN MARINE VESSELS

초록

The hull surface of marine vessel constists of curved thick plates that are divided from the hull form. The mechanical forming can be an efficient method for automatic forming of curved plates since it is especially suited to freely curved parts. Considering the manufacturing error induced by springback, a continuous mmultiple-press bending machine composed of a pair of reconfigurable punches is introduced in order to achieve the free forming of curved hull plates using division forming. We also show how forming information is obtained from the given design surface. Although the mechanical bending method is an efficient method, the springback during the elastic-plastic deformation must be carefully considerd into the process parameter. This paper describes the procedure to calculate the proper stroke of each punch for both initial forming and correction forming process. FEA(finite element analysis) is used to simulate the springback of the plate while the strokes are determined by an iterative process of sequential pressing. Springback compensation from an unfolded flat shape to its given design surface using DA(displacement adjustment) method. For the practical application, it is aimed to develop an integrated system that can automatically perform the compensation process and calculate the strokes of punches of the double sides’ reconfigurable multiple-press machine and some experimental results obtained by mechanical bending experiments are discussed.