钻柱粘滑运动的研究应用_石油工程.rar

摘  要：由井下随钻测量的数据可知，钻柱在钻进过程中伴随着各种振动，主要包括轴向、横向和扭转振动，还包括一些异常振动，如粘滑振动。钻柱的粘滑振动是由剧烈的扭转振动和井下摩擦阻所产生的。粘滑振动的现象是：开始一段时间钻头可以保持静止不动或匀速运动，当施加在钻柱速度上的外部扭矩过大时，钻头突然有了一个非常大的初始转动速度最大转速甚至超过了转盘转速的2~6倍。这时在钻柱的粘滑振动过程中，钻头的转速如果在瞬间达到了很大的值，那么就会很容易造成钻柱损坏。另外，在粘滑振动过程中扭矩波动很大，这不仅影响钻井效率也威胁钻井安全，实际扭矩过大可能超过设备所能承受的极限扭矩，致使钻井无法进行。我们用四维模型建立模拟井下钻柱的运动，然后采用数值模拟仿真，以定功率的方式手段，研究粘滑振动的特点，及其规律，并找到相关参数得以控制粘滑振动，减少粘滑振动的不利影响。

关键词:　 滑动运动；非线性控制；四维模型；模拟仿真

Abstract：By the downhole MWD data shows,in the process of drilling, drill string, along with a variety of vibration, including axial, lateral and torsional vibration, but also including some abnormal vibration, such as stick-slip vibration. The stick-slip vibration of the drill string is generated by severe torsional vibration and downhole friction resistance. the phenomenon of stick-slip vibration is:Begin a period of time the drill bit can remain stationary or uniform motion, when the external torque applied to the speed of the drill string is too large, drill suddenly have a very large initial rotation speed of maximum speed that  even more than the rotary speed of 2 to 6 times. Then, in the process of stick-slip vibration of the drill string, the drill speed in an instant to achieve a great deal of value, would be likely to cause the drill column damage. In addition, torque fluctuations would be very large in the process of stick-slip vibration, which affects not only the drilling efficiency,- is also a threat to drilling safety, the actual torque is too large may exceed the equipment can withstand, resulting in the drilling can not run. We use the four-dimensional model to simulated the downhole drill string movement, and then using numerical simulation and given the power means to study the characteristics of stick-slip vibration, and its laws, to find parameters to control the stick-slip vibration, reduce stick-slip vibrationthe adverse effects of stick-slip vibration.

Key words：Drilling string; Stick-slip osciallation; Simulation; Four dimensional mechanic model