螺杆钻具万向轴啮合结构有限元分析

Finite element analysis of the engagement structure of the universal shaft of the screw drill

对某油田现场使用的花瓣式与花键式万向轴啮合结构进行了受力分析;并通过数值仿真分析软件,对不同啮合结构的静载能力、抗疲劳能力与抗磨损能力进行了分析。受力分析结果表明,啮合点产生的不平衡力会对马达产生反作用力,其位置变化越大,对马达反作用力越大。花键与花瓣式万向轴的有限元对比分析结果表明:花键式万向轴的静载能力、抗疲劳能力、铰链结构的抗磨损能力和对马达的反作用力均优于花瓣式万向轴,其静强度提高了29%,对马达的反作用力降低了75%;但花键抗磨损能力要弱于瓣齿,为防止花键过度磨损,花键式万向轴必须带有密封结构为花键提供密封和润滑。

The meshing mechanism of cardan shaft is a weak part in the screw drilling tool, but the research on the meshing structure of cardan shaft is still in the empirical stage, lacking in-depth analysis of the structure, which leads to the passive and lack of basis for the optimal design of the meshing structure of cardan shaft. In this paper, the force analysis of different universal shaft meshing structures used in an oil field is carried out, and the static load capacity, anti-fatigue capacity and anti-wear capacity of different meshing structures are analyzed by numerical simulation analysis software. The force analysis of the universal shaft engagement transmission structure shows that the unbalanced force produced by the engagement point will produce reaction force on the motor, and the greater the change of its position, the greater the reaction force on the motor. The finite element comparative analysis of spline and petal type universal shaft shows that the static load capacity, fatigue resistance, wear resistance of hinge structure and reaction force to motor of spline type universal shaft are better than petal typeuniversal shaft, the static strength is increased by 29%, and the reaction force to motor is reduced by 75%, but the wear resistance of spline is weaker than that of universal body. In order to prevent excessive wear of spline, spline type universal shaft is better than petal type universal shaft. The cardan shaft must have a sealing structure to provide sealing and lubrication for the splines.