Research On Technologies Of The Shaft Part’s NC Machining Based On Machining Features

With the development of global knowledge economy and computer information technology,manufacturing industry plays an important role in the competition of comprehensive national strength. On the basis of traditional machining, through the combination of NC technology and CAD/CAPP/CAM technology, NC machining process is formed. Compared to the traditional processing technology, which has a great advantage, and becomes an important processing technology in contemporary manufacturing. Combined with the research of CNC technology of shaft parts,this subject explores the solution of some key problems in NC process design, so that the works of this subject have an important practical significance.In view of the pursuit of high efficiency and high quality products for the enterprises,this paper takes the shaft part as the research object and carries on the numerical control processing technology research. Based on the feature recognition strategy, the recognition and extraction of parts manufacturing feature are realized; According to the present situation of CAPP system for process planning, the automatic design of CAPP system is studied, which includes the design of process knowledge base and process feature segment, parameter definition and process definition; After the analysis of the processing characteristics and machining path generation for the shaft part,the abstract axis model in this paper is taken as the object ,which is carried out by using the CAM function of UG in respects of the computer aided processing and NC program generation; In order to verify the correctness of NC program in actual production, the virtual machine tool is established based on the prototype of NC machine tool, the feed optimization in the program is optimized, and the machining process of the part is simulated finally.The results of example-analysis show that: ①The rule-based feature recognition strategy not only can efficiently and accurately extract the parts features, but also considers the parts processing order, which can provide information support for the subsequent parts process planning; ②When generating part-process ,the parametric CAPP system designed in this paper can effectively overcome the shortcomings of the traditional process design, such as long cycle length, large amount of work, confusion of management etc;③The virtual machine tool established in this subject can find bugs in the program safely and intuitively, at the same time,it could easily modify and optimize the machining program of parts and reduce production costs by replacing the "trial cut" link in actual production.