Research On Rapid Programming Technology Of Numerical Control Machining For Typical Structure Of Shell Products

With the rapid development of aerospace technology and the application of the integral NC machining technology,the types,states and quantities of numerical control machining of aerospace shell products are growing,and the complexity and integration of structural features are gradually improved.With the increasing demand for aerospace production tasks,and shorter and shorter product development and batch production cycle,production tasks place higher requirements on the efficiency and reliability of NC machining.As an important part of NC machining,NC programming affects the production cycle and processing quality of products,and the complexity of product structure leads to low efficiency and high error rate of NC programming.Therefore,in order to achieve high-efficiency and high-quality NC machining of aerospace shell products,fast and reliable NC programming is an outstanding issue that needs to be solved.Aiming at the problems and difficulties in numerical control programming of aerospace shell products,this paper developed a rapid programming technology based on the typical structure of shell parts and established an efficient programming method based on CAD and CAM system by using secondary development technology.By applying this method,not only the numerical control programming efficiency and the process design reaction capability during the development stage and the technical state change stage but also the processing efficienncy and quality stability of the approved product are improved.The specific research contents are as follows:Firstly,the problem of feature modeling method,tool path planning and NC machining process is described,and the overall technical solution is formulated based on this.Aiming at the problems of low efficiency and poor product quality stability of the process design during the NC machining process of aerospace shell products,this paper teased out the typical features of the aerospace products and then optimized the NC programming of these typical features.The automatic matching of typical features is achieved by using graph matching algorithm.At the same time,by secondary development technology,this paper established rapid programming module.To avoid the difference of programming quality and processing efficiency caused by the difference in skill level of technologists and to reduce personnel error,this module recognizes features automatically based on typical features,strictly defines the corresponding machining operations according to different types and geometries of machining features,and programsthe machining processes reasonably for each feature.In order to improve the quality of the shell process design,this paper: made mature process scheme more instructive and referable by adopting standardized design process;completed the optimizations of cutting strategy based on machine performance to avoid the difference of processing efficiency caused by difference of equipments,;completed the tool standardization study to avoid the problem of poor quality stability caused by the situation that operators need to modify the cutting parameters on the spot according to the selected tool,and to improve the production efficiency and processing quality ultimately.In order to verify the correctness of the fast programming module generation program and avoid the collision between the machine and the part or between the tool and the part during the machining process,this paper used VERICUT to establish the simulation model and simulate NC machining process in real environment to improve the processing quality and the program reliability,and then selected a typical shell product as research objects to verify cutting performance using self-developed rapid programming technology.The simulation and trial cutting results show that the program generated by the fast programming module is accurate and reliable,and improves the processing efficiency and quality.