In the rubber industry, screw extruder is very important processing equipment. The screw extruder is developed with the development of its core component, the screw extruder configuration. Based on the analysis of the characteristics of screw structure, the theoretical analysis of screw configuration is made in this paper. The extrusion mechanism, main action and advantages and disadvantages of various screw configurations were analyzed. The effect of screw configuration on extrusion process is analyzed. Studying the working principle of screw with different configuration and its influence on the extrusion process will be beneficial to the further optimization of screw structure design and the development of new screw, and thus to the development of rubber industry. Moreover, the research on the structural characteristics of different screw configurations is the foundation of the development of the special CAD system for rubber screw. It is also the basis to optimize the design function of CAD system for rubber screw. At present, a lot of special rubber machinery CAD in AutoCAD or PRO - E on some simple secondary development, the development is based on structured, reuse not only very bad not to carry on the deep level development, but also difficult to meet the needs of diversified complex systems, it is difficult to achieve extended and reused, and hard to solve the special rubber machinery across processes in the design of CAD system, cross-platform transplantation and distributed application, etc. To solve these problems, the selection of system design patterns and system reusability and scalability become the key points of system design. At present, multiple design patterns can be used to skillfully reuse software objects and design the system structure of software from a top-level perspective. The com-based component object model is fully capable of implementing compatibility in various forms based on binary executable code level, thus achieving good reuse. COM - based component object model is a feasible way to realize CAD system. In this paper, on the basis of research on different screw configuration, according to the rubber extruder screw the characteristics of CAD parametric design, using c + + object-oriented development language, as a functional unit, and USES the COM components for the automatic generation of rubber extruder screw system structure design, the system can easily realize the expansion of the future and code reuse and used to implement distributed applications, this greatly improves the development efficiency. Finally, on the Visual C++ 6.0 development platform, under the guidance of the idea of "feasible path", the development of com-based "rubber screw automatic generation system" was completed.