An Expert system for near net shape axisymmetric forging die design

ABSTRACT AN EXPERT SYSTEM FOR NEAR NET SHAPE AXISYMMETRIC FORGING DIE DESIGN YILMAZ, Necip Fazıl Ph. D. in Mechanical Engineering Supervisor: Assoc. Prof. Dr. Ömer Eyercioğlu June, 2002, 248 pages In this thesis, the application of rule base expert system to the near net shape axisymmetric forging die design, and development of a knowledge base for it, is carried out. The developed system is aimed to cover the design of forging dies for axisymmetric parts and meet them with the power of expert system. This package has a modular structure and has been undertaken in the four main chapters. Firstly, the drawing file of a final product, taken from AutoCAD, is converted into DXF format and it is integrated with the system by means of feature recognition module. After the recognition of input geometry of the product, checking that whether it is forgeable in closed die or not forms the second step. In the third stage, the required forging load is calculated so as to fill the die cavity completely. The power and energy requirements for making the finished forging are also determined at this stage. Die stress calculation and die shape determination come after this process as a fourth chapter. In this chapter, amount of thermal shrinkage due to temperature difference and elastic expansion between workpiece and die is taken into account. The main contribution of this thesis is the realisation of forging die design for not only specific industrial parts but also all axisymmetric components. For this purpose, an expert system application is developed for the recognition of product geometry, forging load calculation and the determination of die dimensions. mThis study has knowledge base structure in general and rule base in particular. In the program special inference engine has been developed. The developed expert system is written in Borland C++ language by using lots of database and SQL (Structured Query Language) facilities. Key Words: Expert System, Axisymmetric Forging, Die Design, Near Net Shape Forging IV