电潜螺杆泵传动轴多载荷作用力学特性与疲劳寿命分析

分析电潜螺杆泵举升过程传动轴断轴部位应力分布及疲劳寿命对提高传动机构可靠性和保障电潜螺杆泵连续稳定运行具有重要意义。针对传动轴断轴部位，提出传动轴多载荷作用力学特性分析和疲劳寿命预测方法。数值仿真和现场测试分析结果表明：各载荷单独作用时，销孔应力较大区域沿径向条状分布且应力分布较均匀，内螺纹应力较大区域沿径向自上向下逐渐减弱，且最大应力受扭矩作用最大而受狗腿度产生的弯矩作用最小；各载荷组合作用时，轴向力对销孔和内螺纹应力分布影响最大，且最大应力均小于许用应力而推断两处断轴原因不是超载导致的脆性断裂；内螺纹处疲劳寿命明显小于销孔处疲劳寿命，为传动轴优化设计提供依据。

Mechanical Characteristics and Fatigue Life of Drive Shaft of Electric Submersible Screw Pumps under Multiple Loadings

Analysis of the stress distribution and fatigue life of the broken shaft of the drive shaft during the lifting process of the ESP is of great significance for improving the reliability of the drive mechanism and ensuring the continuous and stable operation of the ESP. Aiming at the broken shaft part of the drive shaft, the mechanical characteristics analysis and fatigue life prediction method of the drive shaft under multi-load action was proposed. The results of numerical simulation and field test analysis show that when each load acts alone, the stress area of the pin hole is distributed in strips along the radial direction and the stress distribution is relatively uniform, and the stress area of the internal thread gradually weakens from top to bottom along the radial direction, and the maximum stress is most affected by the torque, and the bending moment caused by the dogleg is the smallest; when the loads are combined, the axial force has the greatest influence on the stress distribution of the pin hole and the internal thread, and the maximum stress is less than the allowable stress, so the reason for shaft breakage is not brittle fracture caused by overloading; the fatigue life of the internal thread is significantly shorter than that of the pin hole, which provides a basis for the optimal design of the transmission shaft.