Modeling of Broaching Process for Improved Tool Design

Abstract

High productivity and high quality can be achieved in broaching if the process is applied properly. Roughing, semifinishing and finishing can be performed in one stroke of the tool increasing productivity and reducing set-up time. Furthermore, high quality surface finish can be obtained due to straight motion of the tool. One big disadvantage of broaching is that all process parameters, except cutting speed, are built into broaching tools. Therefore, it is not possible to modify cutting conditions during the process once the tool is manufactured. Improved design of broaching tools needs detailed modeling and analysis of the broaching process. In this paper, tool optimization method and process models are presented. Cutting forces, tooth stresses, part deflections are modeled and analyzed using cutting models and FEA. The results of the analysis are summarized in analytical forms so that they can be used for other applications although turbine disc broaching is considered as the application which is one of the most complex broaching operations. Application of the model for improved and optimized tool design are demonstrated by examples.