中文摘要：

研究铝型材平面分流组合模的设计流程和关键技术，运用反推分析法，从模具结构向工艺参数反推，确定设计流程中的关键点，并使其模块化，构建平面分流组合模CAD系统总体框架。通过分析模具结构的实体建模方法，提出各个模块的具体设计方法。基于UG／OpenAPI和UG／OpenGrip，对UG的基础功能进行集成，采用uF对象模型进行逐步建模，实现平面分流组合模CAD系统设计。实例表明，采用该系统可较为方便地设计出复杂空心铝型材平面分流组合模。

英文摘要：

The design processes and key technologies of porthole dies were investigated. The key points of design process were determined and modulated by using the back-stepping analysis method from the die structure inverse to process parameters. The whole framework of CAD system of porthole dies was then built. The specific design ideas of each module were also presented by analyzing the modeling approach of die structure. A CAD system of porthole dies was developed based on UG/Open API and UG/Open Grip to integrate the UG＇s basic functions and by using step-by-step modeling of UF object model. The design example shows that porthole dies can be designed con- veniently by using this system.