The Research On Five-axis NC Machining Technology For Curved Surface Of Flue Gas Turbine Moving Blade

The moving blade is the key part of the flue gas turbine, and the running efficiency and the working performance of the equipment are affected by its machining quality. Because of the particularity of the blade material and the complexity of the blade body surface, it is difficult to guarantee the machining precision of the blade, which puts forward higher requirements on the processing methods, equipment and process plans. Five-axis machining technology as the best choice of free-form surface machining, it is very suitable to complete the high efficiency and high precision machining of the blade.Based on the analysis of the commonly machining method and actual technology problem of blade, the research focus on the five-axis machining technology of the blade of flue gas turbine and the surface modeling, process parameters determination, tool path planning and post processing in the machining process. Firstly, according to NURBS surface modeling technology, the B spline fitting of the blade section line is achieved with MATLAB, and the model of the blade is completed with Solidworks. Then, through the theoretical analysis of blade five axis machining process, the process parameters such as blade blank, processing program, processing equipment, cutting tool, machining process and allowance are determined. Taking into account the tool path calculation is a key part of the five-axis machining technology, some key problems of five-axis machining tool path such as the cutting step length calculation, the path interval determined, the interference-checking and the interference-avoiding were researched massively. And the tool path calculation of blade was completed by the PowerMILL software. In order to obtain the NC program that can be used directly to the actual machining, the further research is about the post-processing algorithm of tool swinging/table rotation type five-axis machine tool motion conversion, and the movement calculation formula of each axis is calculated. Finally, the post processing machine tool options file of MAZAK INTEGREX 100-ⅡSY is prepared by using the PM-Post management tools, and the post processing calculation of tool path file that was obtained in pre‐processing is completed.