| The blades are the significant key parts in many power equipment fields such as steam turbine, aircraft engine and marine propeller which have decisive effect on machine working performance. Because the blade profile manufacturing efficiency and machining accuracy and surface roughness have important influence to the energy device performance and conversion efficiency, and the overseas blockade technology of advanced manufacturing blade profile, in addition the blade's complex free-form surface and the material itself being difficult-to-cut, so it made many blade factories generally adopt traditional hand-made machining and grinding blades in China, specially in the blade profile finishing process. This backward grinding way has already could not meet the energy and power industry growing demand, restricted the national defense equipment level promotion seriously. In this paper, it proposed a high-efficient and precision machining turbine blade method with abrasive belt which has universal and cold grinding characteristics and integration of advanced numerical control technology, carried out the belt grinding mechanism basic research on heat-resistant stainless steel of turbine blade material, developed the key technologies on the six-axes simultaneous CNC belt grinding machine for turbine blade, had grinding application test to the last stage turbine blade using the prototype grinder, and carried on the appraisal and confirmation for the grinding machine characteristic to affected the grinding accuracy and the surface quality.The main contents in this paper are as following:1) Clarified the critical basis issues on the abrasive belt grinding complex free-form profile of turbine blade, built a grinding test platform for turbine blade made up difficult-to-cut material 1Cr12Ni2W1Mo1V. Established the material removal function model on belt grinding material, carried out the belt grinding experiments based on the above conditions for verify the effectiveness of the function mode, discussed different grinding parameters impact on material removal with modern physical and chemical test apparatus and analysis methods, simultaneously the abrasive belt wear test was carried out to explore the grinding force, the grinding temperature and their interaction in the part surface defects, and completed the comprehensive test and analysis on the abrasive belt grinding 1Cr12Ni2W1Mo1V surface integrity.2) Conducted the study of principle on NC belt grinding profile,proposed a new machining method on the six-axes simultaneous CNC grinding free-form surface in the complex profile part manufacture by the use of wheel-type tool which was made from abrasive belt and contact and drive wheel, the line-contact way of belt by new method insteaded of point-contact way of ball milling tool, greatly improving the efficiency of profile forming, studied the belt grinding blade profile by six-axes CNC with the linear and spline curve interpolation methods, provided the theoretical basis for development high-performance PC-based NC System based on the two interpolation methods,and also designed a fuzzy adaptive grinding controller to turbine blade deformation using the fuzzy algorithm to online adjust PID control parameters, which effective achieved adaptive control of grinding for the profile deformation.3) Developed six-axes belt grinding machine structure innovative through means of digital design software designed machine bed,X-axis component, Y-axis components, Z-axis components, grinding head with double swing, etc. Directed the prototype construction, launched research and development of new six-axes simultaneous CNC system with seven-axes in China, carried out the multi-axis belt grinder positioning precision measurement and compensation using the laser interferometer, proposed the method about multi-axis belt grinding machine positioning precision testing process and compensation which laid the foundation of electro-mechanical technology to ensure the grinding performance of CNC equipment.4) Finished the grinding performance test and validation with this CNC prototype grinding the last stage turbine blade surface, the key factors of grinding performance and surface were tested and analyzed, and using statistical principle conducted scientific evaluation on the grinding equipment performance, at the same time put forward the new adjust natural frequency of turbine blade method by belt grinding technology which can grind different position in the different parameters,and provided theoretical and engineering experiment analysis basis for the grinding application in the factory.
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