扭矩波动系数法监测钻头运行状况

钻头扭矩参数的变化可以反映钻头运行状况，现有的扭矩参数监测方法受扭矩传感器、钻机型号、操作人员等因素影响较大，用设置扭矩门限值的方法监测钻头运行状况，监测效果较差。为此，提出了用监测“扭矩波动系数”代替现有监测扭矩绝对值的方法，并给出其计算模型：通过对现有采集的扭矩参数进行实时数据处理，实时计算测量点扭矩曲线的平均值、扭矩值的标准差，用测量点扭矩值的标准差与扭矩曲线的平均值的比值绘制出“扭矩波动系数”随使用时间的移动曲线，该移动曲线消除了不同扭矩传感器、不同钻机、不同的操作人员所造成的人为影响，更加客观地反映了钻头牙齿、牙轮的实时工作状况。该方法经过现场试验，能更好地预测钻头寿命终结，提高了钻井效率，取得了较好的效果；该方法立足于现有钻头扭矩参数的测量技术，不增加软硬件设备及人员，可在所有的钻井现场推广使用。

Application of the torque fluctuation coefficient method to the monitoring of bit performance

The change of the bit torque coefficient can reflect a bit's performance. However, the existing monitoring method of the torque coefficient is badly influenced by the torque sensor, rig model, operators and other factors; another method of setting the torque threshold value leads to an even worse monitoring result. In view of this, a new method is proposed as well as its calculation model, which is used to monitor the torque fluctuation coefficient instead of the absolute value of torque as used in the previous method. First, the collected data was processed in real time through calculating the average value of the torque curve at the monitoring point and the standard deviation of the torque value; second, a curve was drawn with the ratio of the standard deviation to the average value, reflecting how the torque fluctuation coefficient changes over time. This curve excludes the influence of different torque sensors, rigs or operators and shows the real time performance of the bit teeth and cones more objectively. In the pilot tests, this method predicts the bit life more accurately, thus improving the drilling efficiency and achieving an excellent result, and adopts the bit torque parameters measured by the existing technology without the aid of additional software, hardware or personnel, thus it is worth popularizing and applying at all drilling sites.