The existing research on the subdivision machining of large gear is mainly aimed at large cylindrical gear. Niu Yanfang and Li Weijun analyzed the structural characteristics, processing technology and processing method of large gear ring, and put forward specific measures to preliminarily control the deformation of super large split cylindrical gear. Kang Zaizhang and tengluxiang [9] improved the manufacturing and clamping methods of split large gear, and discussed the manufacturing technology that can effectively control the deformation of large gear. Wu Jing and Wang Wei improved the heat treatment process and clamping method of blank materials, and gave corresponding measures to effectively reduce the deformation of super large split gear. Liu Guanglong and Huang Shitao gave the methods to improve the machining accuracy of split large gear ring from the aspects of material selection, heat treatment and machining methods. Zhang Xiuhua and Peng Cheng gave specific measures to prevent the deformation of split large gear ring from the aspects of gear cutting accuracy, flaw detection, annealing and tooth surface correction. Wang Wei and Wu Jing analyzed the causes of opening deformation of large gear ring, and expounded the measures to effectively reduce opening deformation from the aspects of processing method, stress release and assembly method. Lu Shengkui and Guo Chunfeng analyzed the causes of deformation by changing the processing technology of large gear and according to the experimental results of processing split large gear, and expounded the methods of eliminating internal stress in each processing stage, which not only reduced the processing cost, but also improved the processing accuracy and efficiency of split large gear. CITIC Heavy Industry has successfully processed many sets of split straight bevel gear with a diameter of more than 3000mm on foreign super large equipment, and successfully delivered them.
To sum up, for split cylindrical gear or split straight bevel gear, the existing research focuses on the optimization of machining process and the specific measures of deformation control. There are few reports on the deformation mechanism of split large gear machining, and there are no relevant literature reports in foreign high-level journals. In order to realize the high-precision machining of super large split gear, the deformation in the machining stage of split gear must be deeply and systematically studied.