谐壁厚螺杆钻具橡胶衬套线型设计与仿真分析

Linear Design and Simulation Analysis for Harmonic-distance Rubber Bushing of PDM

针对螺杆马达定子橡胶衬套易发生疲劳失效,导致马达工作效率降低,制约钻进速度的问题。建立马达定转子数值模型,分析橡胶衬套工作时的热力耦合问题,并计算橡胶衬套在不同工况及过盈量下的位移、温度及应力分布情况。基于橡胶衬套结构,提出一种新型谐壁厚橡胶衬套结构,并对其进行有限元模拟计算。结果表明,谐壁厚橡胶衬套不仅具有等壁厚橡胶衬套的优点,而且抗磨损寿命及疲劳强度均高于等壁厚,位移分布也较等壁厚均匀,可保证马达的工作稳定性和效率,提高钻进速度。

For the problem of fatigue failure in stator rubber bushing of PDM, which reduces motor efficiency and restricts the rate of penetration, a numerical model of PDM＇s stator-rotor is established. The thermal coupling problem of rubber bushing working in a well is analyzed. The displacement, temperature and stress distribution of rubber bushing under different conditions and interferences are calculated. A new harmonic-distance rubber bushing was designed based on the structure of rubber bushing, and a finite element simulation on it is taken. The research indicates that the harmonic-distance rubber bushing not only has the advantage of equal-distance rubber bushing, but also has higher life of fatigue and anti-wear than the equal-distance rubber bushing,＂ the displacement distribution is more uniform than the equal-distance rubber bushing; the new structure can guarantee the stability and efficiency of PDM stator and increase the rate of penetration.