DESIGN OF PRESS TOOLS

Abstract

Die is the main tool in press forging and drop forging. Die design of forging is done primarily according to rules of thumb and formulae and data from forging design handbook or designer's experience. This prevailing procedure is effective but is difficult to control quantitatively metal flow in a die cavity. For example the shape of a finished forging can not be formed directly from a pancake like billet in one die station so it has to be preformed previously. Also it is not known what is the simplest preformed figure for a complicated forging nor what is the optimum flash geometry to obtain full filling of a cavity for minimum material waste. There is insufficient available knowledge to prevent these situations for the wide range of shapes that are forged. Therefore it is usual in design to allow more raw material to be consumed as scrap to assure production success. The advanced simulation Technique FEM has been developing rapidly in recent years and many interesting result in die forging process have been reported. However there are still reservation in applying these technique in production because of it's cost and complexity. In the present work we have tried to look at this problem in a different way what is more easily available, known and practiced is kept in mind while going for new technologies. A simple die design problem has been undertaken of a bell crank lever. Than a multi impression die has been selected and solutions are determined, fullering, preform, finish impression are designed by providing suitable allowances incorporated with die layout dimensioning, stock calculation. In second part I tried to look for new technological and more scientific solutions