Abstract：Contact between the driving wheel of a horizontal well crawler and the casing pipe wall causes plastic deformation indentations in the pipe wall. The indentation morphology then greatly influences the crawler motion with the oblique indentation contact between the wheel teeth and the pipe wall being a very complex process. A theoretical model was developed to analyze the indentation formation for various loading conditions with positive pressure and torque on the gear tooth to the oblique indentation. The loading effects can be divided into 6 different action areas. Slip line theory was used to analyze the pressure distribution for various contact states of the gear tooth in each region in a mechanical calculation model relating the load on the gear tooth and the indentation morphology. The critical loads between the action zones are identified with forward and backward application methods of the theoretical model. Finally, theoretical models of the four stabilization zones are characterized based on their indentation depth, amount of slip, indentation morphology and pressure distribution on the contact surface, and the indentation verification test was also carried out. The simulations and tests show that the load division between the gear teeth is reasonable and the theoretical model is accurate. This lays a foundation for optimization of the crawler load control strategy and the modeling and optimization of the multi-tooth traction force on the drive wheel.
孙可平, 杨东超, 常旭, 朱衡, 鲁沛昕, 陈恳. 爬行器驱动轮与套管管壁斜压过程分析[J]. 清华大学学报（自然科学版）, 2019, 59(12): 1016-1028.
SUN Keping, YANG Dongchao, CHANG Xu, ZHU Heng, LU Peixin, CHEN Ken. Analysis of oblique indentations caused by the tractor driving wheel and the casing pipe wall. Journal of Tsinghua University(Science and Technology), 2019, 59(12): 1016-1028.
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