一、前言 YTC-1几何构形系统是作者于1986年初步开发的适用于锻模CAD的通用系统。实现锻模CAD需要开发描述模锻件的三维软件。目前关于锻模CAD的专用系统,美、英、日等国家均有应用,但是锻模CAD的通用系统,国外也处于研究开发阶段。设计轴杆类锻件的锻模,要比设计齿轮类锻件的锻模困难,这是因为要作出锻件的截面积图和计算毛坯图(直径图)。这两个图是选择工步、选择棒料尺寸和设计制坯型槽所不可缺少的基础。作出这两个图的传统方法是:根据锻件图,将锻件各个有代表性的 I. Introduction YTC-1 geometric configuration system is a general system developed by author in 1986 for die CAD. To achieve forging CAD requires the development of three-dimensional software describing forgings. At present, the special system of forging die CAD has applications in the United States, Britain, Japan and other countries. However, the universal system of forging die CAD is also in the research and development stage abroad. It is more difficult to design forging dies for shaft forgings than forging dies for gear forgings, because of the cross-sectional area of ​​the forgings and the calculation of the blank (diameter). These two figures are the indispensable foundations for selecting the work step, selecting the bar size and designing the billet. The traditional method of making these two figures is: According to the forgings, the forgings are all representative