螺杆钻具转子系统不对中的故障产生机理与诊断

螺杆钻具是由多个可以旋转的转轴通过万向联轴器连接成的一个轴系,主要用来传递转矩从而带动钻头运动。但是在安装或者在万向联轴器自身磨损消耗下,钻具会出现轴线上的不对中,进而引发一系列故障,比如螺杆钻具的螺杆马达转子联轴器偏移、轴承移动、转轴发生形变、油膜失稳等,导致机器发生振动并造成一系列的危害。因此,在实验室条件下,研究井下动力钻具不对中的故障产生机理,掌握不同故障的特征,并及时进行故障诊断,对减小或避免由于转子联轴器不对中而产生的故障具有十分重要的意义。本文借助于DHRMT双跨转子台高度模拟井下的钻具故障,设置转子不对中的不同故障类型,通过实验获得钻具转子不对中故障造成的振动特征,为井下动力钻具设计及改进提供参考依据。

Research on the mechanism and diagnosis for screw drilling tool misalignment

The screw drill tool is a shaft system consisting of a number of rotating shafts connected by a universal coupling,which is used to transfer torque to drive the bit motion.However,owing to the installation or wear and tear of the universal coupling itself,the axial misalignment of the drilling tool will appear,leading to a series of failures,such as offset of the screw motor rotor coupling,bearing movement,shaft deformation,oil film instability,etc.,leading to vibration of the tool and a series of hazards.Therefore,it is of great significance to study the failure mechanism of downhole power drilling tool misalignment,grasp the characteristics of different failures,and timely diagnose the failures under laboratory conditions,so as to reduce or avoid the failures caused by misalignment of the rotor coupling.In this paper,the DHRMT double?span rotor bench is used to simulate various downhole drilling tool failures through setting of rotor misalignment,and the vibration characteristics caused by rotor misalignment is obtained through experiments so as to provide a reference for downhole power drilling tool design and improvement.