The development of a metallurgical CAPP system for large steel forgings.
type: CreativeWork
description: The development of CAPP (Computer Aided Process Planning) systems promises improvement to the design efficiency and quality of process plans, whilst maintaining knowledge for future developments. Although considerable progress has been made in Computer Aided Process Planning, most of the systems developed or under development so far are limited to one manufacturing operation and to planning for an individual part design. The systems lack an overall structure for real manufacturing practice. This thesis examines the problems involved in the planning of an extensive manufacturing task involving many different processes including chemical and thermal treatments. On the basis of the evaluation of the manufacturing system in the collaborating company, an intelligent database system has been designed to solve metallurgical process planning problems involved in the manufacture of large steel forgings. In this CAPP database system, two hierarchy control levels involving a number of local planning areas have been adopted to allow the development of process sub-plans as well as supporting engineering data. All the process sub-plans have been integrated into a single system rather than isolated as separate entities within the overall metallurgical process planning system together with quality assurance control and other functions. These sub-plans, however, are planned and modified in the separate planning areas, the development being conducted on facsimile data records. Only when each sub-plan has reached a satisfactory state of development is it issued - made available to the overall system - by transferring the facsimile records into the system data files, the facsimile records then being discarded.Metallurgical process knowledge and rules have been incorporated into the database. These allow the system to assist users to make decisions and achieve final desired process plans. A versional approach has been developed to organise and control the stage by stage evolution of iss…
abstract: The development of CAPP (Computer Aided Process Planning) systems promises improvement to the design efficiency and quality of process plans, whilst maintaining knowledge for future developments. Although considerable progress has been made in Computer Aided Process Planning, most of the systems developed or under development so far are limited to one manufacturing operation and to planning for an individual part design. The systems lack an overall structure for real manufacturing practice. This thesis examines the problems involved in the planning of an extensive manufacturing task involving many different processes including chemical and thermal treatments. On the basis of the evaluation of the manufacturing system in the collaborating company, an intelligent database system has been designed to solve metallurgical process planning problems involved in the manufacture of large steel forgings. In this CAPP database system, two hierarchy control levels involving a number of local planning areas have been adopted to allow the development of process sub-plans as well as supporting engineering data. All the process sub-plans have been integrated into a single system rather than isolated as separate entities within the overall metallurgical process planning system together with quality assurance control and other functions. These sub-plans, however, are planned and modified in the separate planning areas, the development being conducted on facsimile data records. Only when each sub-plan has reached a satisfactory state of development is it issued - made available to the overall system - by transferring the facsimile records into the system data files, the facsimile records then being discarded.Metallurgical process knowledge and rules have been incorporated into the database. These allow the system to assist users to make decisions and achieve final desired process plans. A versional approach has been developed to organise and control the stage by stage evolution of iss…
author: Deng, Wenzhong.
language: en
date published: 1995
date modified: 2026-07-24T06:31:21Z
provider: Sheffield Hallam University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Sheffield Hallam University (United Kingdom).