Oriented Product Research And Development Of The Capp System

CAPP is a major component in CIMS. It not only acts as a tie which joins CAD and CAM systems together, but also keeps close links with other sub-systems such as MIS, MRP, etc. in CIMS. Therefore, CAPP has been regarded as an important research field of modern manufacturing technology. For many years, a lot of new theories and methods have been put forward in this field, but the application coverage of CAPP is still very limited. In fact, almost all of the CAPP systems are developed as specialized system for special parts (such as polyhedrons, cylinders), and some of them cannot be used under network circumstance, so the data consistency and integrity required by CAD and CAPP cannot be assured. Thus, there is immediate significance in further promoting the practicality of CAPP technique while reinforcing the study of CAPP theories.In this dissertation, the current achievement of domestic and worldwide research and existing difficulties of CAPP is summarized, with he intention and significance of developing a product-oriented CAPP system expounded. Based on the principle of practicality and universality, the careful analysis and study of this system has been given in this thesis in combination with the process planning of Tianjin Textile Machine Mill. This system is designed to be Client/Server architecture and utilizes series advanced computer techniques; also, it combines the experience of several kinds of CAPP systems having developed together. This system makes the whole product applied subject and process knowledge database and product process database as the core. Through utilising a variety of supporting tools, it can be used widely in the framework system of interchanging CAPP in all kinds of enterprises at different levels or different process sectors that combine the process design with information management as a part in an enterprise.First, the dissertation sets the overall objective of the system development according to the practical requirement that the enterprises have on the process design and the functions and establish the function models. IDEFO is utilised to analyze the functions and establish the function models. IDEFlx is used to analyze the data process and set up information models. At last, the system structure of the systems and the distribution of the computers are selected to form a product-oriented CAPP system. The followings are mainly studied.The design and development of the product information sub-system based on Object-Oriented techniques, putting forward modelling methods of Object-Oriented product information and making the formation of product structure tree based on productinformation that is input.The function and data-storing structure of BOM in a product-oriented C APP system, raising the single child-single parent storing method of product-structure BOM in relation database, modelling methods of process file management model with BOM as the core and purview control methods of process file, realizing process planning based on product structure tree. The process information tree can be constructed according to product structure tree. With process information tree as the organizing formation, the process file can be reused and restored in the system. I can also restrict the unauthorized modification of process documents. The efficiency of process planning is improved by means of reusing existent data generated and restored in the system.The principle of process workflow, exploring process planning working flow management based on workflow management techniques, putting forward forming methods of process workflow models, keeping track of the development of design methods with process workflow management sub-system.