Stick-Slip Detection and Friction Factor Testing Using Surface-Based Torque and Tension Measurements

Abstract

Abstract Recently, there has been a strong push towards automation and the use of real-time models in the drilling industry. However, it has been recognized that these new methods require a drastic improvement in the quality of sensor data gathered at the rig. In this paper, we investigate how accurate measurement of drill pipe torque and tension at the surface can be used to diagnose downhole conditions. A surface-based torque and tension sub was used to perform measurements while drilling several extended reach horizontal wells in the Dilly Creek area of the Horn River Basin. A filtered version of surface torque was used to calculate a stick-slip metric which was compared to stick-slip measurements using a downhole tool. The results show that there is reasonable correlation between surface and downhole metrics, but the correlation is highly dependent on torque filter stop frequency. A comparison is also performed between the hookload measured with a deadline sensor and the tension measurement from the surface sub. The results show a systematic discrepancy of approximately 5% that is likely due to sheave friction. A commercial torque and drag software package is used to show that values for casing friction factor may be underestimated if sheave friction is present but ignored in the analysis.