College of Mechanical Engineering, Yangtze University
Hubei Provincial Innovation Center of Enterprise-University Alliance on Intelligent Petroleum Machinery
China Energy Digital Technology Group Co., Ltd.
Cnooc Energy Development Co., Ltd., Engineering Technology Branch
Hubei Jiaye Petroleum Machinery Co., Ltd.

旋冲钻具能有效提高深层、硬地层的破岩效率，具有广阔的应用前景。凸轮−滚轮是实现冲击动作的关键机构，但复杂多变的井下环境导致机构损伤严重，进而影响破岩效率。基于旋冲钻具多井次的试钻数据，建立凸轮−滚轮动力学模型，通过显式动力学(Autodyn)分析不同冲程、转速、钻压下的工作特性，总结机构的形变特征提出优化方法。分析结果与试验数据和理论数值对比，验证了计算模型的准确性。结果表明：冲程增大可提高冲击效果，但高于10 mm冲程的滚子实际运动轨迹受钻速、滚轮尺寸、凸轮轮廓曲率影响其轨迹将变平缓。转速在9~18 rad/s时轴向加速度波动幅度较大，对钻具的稳定性具有一定影响。钻压增大凸轮内缘处形变特性明显，其形变量与钻压成正比，25 kN钻压下凸轮的形变量约是10 kN的2.6倍。凸轮齿顶、滚轮内缘处为易变形点，在齿顶处安装可换滚筒同时改变滚轮为鼓轮构型并对抛物线−直线−抛物线、2次多项式、摆线、7次多项式4类凸轮轮廓线型进行特性分析。选用摆线及7次多项式凸轮座轮廓和鼓轮可提高冲击效果，计算结果可为旋冲钻具设计提供参考依据。

Rotary percussion drilling tools can effectively improve their rock breaking efficiency in the deep and hard strata, thus having broad application prospects. The cam-roller is the key mechanism to realize the impact action, but the complex and changeable downhole environment leads to serious damage to the mechanism, which in turn affects the efficiency of rock breaking. Based on the test drilling data of rotary impact drilling tools in several wells, the cam-roller dynamics model was established, the working characteristics under different strokes, speeds and drilling pressures were analyzed by Autodyn (explicit dynamics), and the deformation characteristics of the mechanism were summarized to propose an optimization method. Besides, the analysis results were compared with the test data and the theoretical values to verify the accuracy of the calculation model. The results show that increasing the stroke can improve the impact effect, but the actual motion trajectory of rollers with a stroke greater than 10 mm will become smoother due to the influence of drilling speed, roller size, and cam contour curvature. When the rotating speed is 9‒18 rad/s, the fluctuation of axial acceleration is large, which has a certain influence on the stability of drilling tools. The deformation characteristics at the inner edge of the cam are obvious when the drilling pressure increases, and its deformation is directly proportional to the drilling pressure. The deformation of the cam under 25 kN drilling pressure is about 2.6 times of 10 kN. As the top of the cam tooth and the inner edge of the roller are easily deformed points, a replaceable roller was installed at the top of the tooth and the roller was changed to the drum configuration. Thus, the characteristics of four types of cam contour lines: parabolic-straight-parabolic, quadratic polynomial, cycloid and seventh degree polynomial, were analyzed. The results indicate that the use of cycloid and seventh degree polynomial cam seat profiles and drum roller could improve the impact effect, and the calculation results could provide a reference basis for the design of rotary percussion drilling tools.

国家自然科学基金项目(51974035，U1262108，U1762214)；湖北省重点研发计划项目(2020BAB055)

孙养清，易先中，万继方，等. 旋冲钻具凸轮−滚轮冲击机构工作特性分析[J]. 煤田地质与勘探，2024，52(3)：164−175.

SUN Yangqing，YI Xianzhong，WAN Jifang，et al. Analysis on working characteristics of cam-roller impact mechanism of rotary percussion drilling tool[J]. Coal Geology & Exploration，2024，52(3)：164−175.