Feature-based design for process planning of the forging process

Abstract

The forging process has traditionally been done by skilled experts using their past experience, intuition and the trial and error method. Even in this computer era, only a very few computer aided tools are available for this oldest manufacturing process. The present work explains the development of a feature based design system that has been applied in the concept-to-manufacturing stages of the forging process. It is broadly divided into four modules namely, feature-based design (FBD), virtual factory environment (VFE), feature mapping for forging (FMF) and process planning (PP). The FBD module is used for the design, modelling, synthesis, representation and validation of the component for the forging application. It uses integrated features, which are pre-defined as feature templates in the developed feature library. While instancing these integrated features, the database gets/derives the information required for the design, modelling, process planning and manufacturing stages of the component as its attributes, from the user/knowledge base. After creating the component, the integrated features present in the model are validated with respect to the forging process. The VFE module defines the layout model of the factory on the computer, and provides the database for the machines, machine tools, tools, work pieces, etc. The FMF module contains the knowledge base for preparing the forge model, die impressions, parting line/surface, etc. The PP stage is used to find the process parameters like forming sequence, shape of pre-form and finisher die sets, temperature of billet and dies, forming speed, die stroke, material for die sets and workpieces, etc. This feature based design system has been built using existing CAD, programming and spread sheet software tools namely CATIA®, MS-Visual Basic® and MS-Excel®, which not only save developmental effort, but also make full use of the functionalities of these commercial software tools. This paper explains the developed system with a case study.

Keywords:

• Feature-based design
• Forging
• Virtual factory
• Process planning