A Knowledge-Based Approach to Spur Gear Fabrication in Precision Forging Process

Abstract

Designing forged gears with constrained involute tooth profile is a time-consuming activity with high costs due to the complexity in the plastic deformation, machine limitations, and trial-error iterative methods used to design dies and develop process conditions. Recently, knowledge-based systems are proving to be a powerful tool and a great potential for developing intelligent design support systems to improve quality of products and reduce costs by eliminating or minimizing many of the trail-error iterations involved in process design. This paper describes research work in developing a knowledge-based gear design and manufacturing system that assists des igners to reduce the time needed to design precision forged solid gears and provide detailed process specification along with the required process model implemented in it. The system integrates knowledge about all aspects of gear design and manufacturing and provides powerful reasoning and decision-making capabilities for reducing the time between detailed design and final production. Once the user specifies the basic design requirements, the system automatically carries out geometric calculations and strength analysis according to American Gear Manufacturers Association (AGMA) standards, power rating and Finite Element Analysis (FEA) based techniques. With a successful power rating achieved, the system automatically feeds input parameters into the GEARFORGING program and carries out process planning for the gear forging process. Estimation of the number of preforming stages required, generation of detail die drawings, geometric parameters, and estimation of forging load and energy requirements of the process are calculated based on available material design databases, knowledge-based rules and feature-level calculations. The system generates the whole forging process from the billet to the final gear product. The results have been compared with those available in the current literature and good agreement has been demonstrated.