A STUDY ON SEGMENTED MULTIPLE-STEP FORMING OF DOUBLY CURVED THICK PLATE BY RECONFIGURABLE MULTI-PUNCH DIES

摘要

Doubly curved thick plate forming in shipbuilding industries is currently performed by a thermal forming process,called as Line Heating by using gas flame torches.Due to the empirical manual work of it,the industries are eaaer for an alternative way to manufacture curved thick plates for ships.It was envisaged in this study to manufacture doubly curved thick plates by the multi-punch die forming.Experiments and finite element analyses were conducted to evaluate the feasibility of the reconfigurable discrete die forming to the thick plates.Single and segmented multiple step forming procedures were considered from both forming efficiency and accuracy.Configuration of the multi-punch dies suitable for the segmented multiple step forming was also explored.As a result,Segmented multiple step forming with matched dies had a limited formability when the objective shapes become complicate,while a unmatched die configuration provided better possibility to manufacture large curved plates for ships.