Development Of3-D Foundry Design CAD System For Cast Steel With Sand Mold

Foundry, which represents an important sector of manufacturing industry, typically has the profound effect on national economy. A casting design system for steel castings and iron castings was developed in this thesis, which would help with improving casting design efficiency and quality. It was believed to be helpful for utilization of scientific management on casting design.Manufacturing industry is the fundament of national economy, and it is CAD/CAM softwares that are the key supportive softwares. When CAD/CAM softwares were applied, not only the design period would be shorten, but the cost would be relieved. However, the key technology of CAD/CAM softwares are still dominated by foreign countries, as a result of which, the market in China are dominated by foreign enterprises, too.According to the theory of casting design, a system was developed on Sinovation, which is a kind of high-end CAD/CAM software with the copyright in opposition of Chinese enterprise. With the awareness of source code of Sinovation, wizard pages were developed by MFC procedures, while database and model creating procedure were developed by Microsoft Access2003and Script language, respectively.This system is divided into several sectors, including hole-filling, machining allowance addition, draft, model-enlarge, modulus calculation, feeder design, gating system design and hot-spot prediction. In the case of modulus calculation for whole casting, this system would obtain the volume and surficial area with the help of " material property" function provided by Sinovation, followed by the calculation of their ratio. While in the case of fractional casting modulus calculation, four kinds of methods, which are cubic box, ball, cylinder and exist solid, are provided respectively. It was tested that this kinds of section selecting methods provided more precise result of modulus, in contrast to those in other CAD systems. It could be chosen by customers that which one of the two kinds of feeder modulus calculation methods, modulus method and cubic equation method, should be utilized. Modulus method is a kind of empirical evaluation by multiplying a ratio to the casting modulus, while cubic equation method is a kind of precise calculation based on strict math method. In addition, considering that it is common that feeders on casting should have a certain height, the relationship between feeder modulus and feeder height was deduced in this paper. The relationship of feeder modulus and feeder size was also included.Another highlight of this paper would be the improvement of the model of point modulus, which was used to calculate possible location of hot-spots in the case of three dimensional orthogonal grids. The result was fine. Finally, this system, which has friendly interface and steady functions, would help improve casting design accuracy and efficiency.