The Development Of CAD System For Sand Casting Of Steel

Casting process is an important part of casting production, which designs the programs, parameters, art work sheets and process charts, and so on. It is combined with Computer Aided Design, which will improve the traditional manual design of casting process and increase the technological design level and efficiency. In the thesis, the foundry technique aided design software for cast steel was developed.The software takes the Windows XP operating system as R&D Platform for its high stability and safety. There are three developing tools which are supplied as the interface to AutoCAD, such as AutoLisp, ADS( AutoCAD Development System) and ARX(AutoCAD Runtime extension). In these developing tools, AutoCAD Runtime extension has the best design efficiency and the most functions, which uses c or c++ as the developing language. The library of ObjectARX has a group of common tools which can use the development structure of AutoCAD and access its data structures, graphics and the core of geometric modeling. Then the developers can use the extensional classes and functions at its running time and has the special power of its own new orders. Because of the selection of AutoCAD 2004 and ObjectARX, Visual C++.NET 2002 is used as the developing platform. Microsoft Office Access 2003 is used to create data files, which can be learnt and used with its visual guide easily. At the same time, the ODBC (Open Database Connectivity) is used to access data in the inner programs. During the design process, the MFC (Microsoft Foundation Class) and ODBC are sufficiently used so that the software has a user-friendly interface and the technological parameter database management function.The software consists of four computation and design modules, which are the module for the allowance for finish of the machinable face, the module for allowance for shrinkage to correct the dimension change for solidification, the module for pattern draft to increase inclination and the module for minimal hole to get the size of minimal hole in the steel casting.According to the application for the castings technological parameters, the results show that the software can run steadily and intuitively in the 3D environment of AutoCAD 2004. Users can browse and update the technological parameter database more conveniently, which enhances the efficiency of data search.