|Title||Anti-torque systems of electromechanical cable-suspended drills and test results|
|Author(s)||Pavel Talalay , Xiaopeng Fan, Zhichuan Zheng, Jun Xue, Pinlu Cao, Nan Zhang, Rusheng Wang, Dahui Yu, Chengfeng Yu, Yunlong Zhang, Qi Zhang, Kai Su, Dongdong Yang, Jiewei Zhan|
Annals of Glaciology
To prevent spinning of the upper non-rotated part of the electromechanical drill, an ‘anti-torque system’ has to be included in the downhole unit. At the same time, the anti-torque must allow the drill to move up and down the borehole during drilling and tripping operations. Usually the anti-torque system has a blade form of various designs that engages with the borehole wall and counteracts the torque from the stator of the driving motor. This paper presents a review of the different anti-torque systems and test results with selected designs (leaf spring, skate and U-shaped anti-torque systems). Experiments showed that the skate anti-torque system can provide the maximal holding torque between 67 and 267 Nm−1 depending on the skates’ outer diameter and ice temperature, while the leaf spring anti-torque system can provide only 2.5–40 N m−1 (in case of straight contact between the ice and the leaf springs). The total resistance force to axial movement of the skate anti-torque system lies in the range 209–454N if the system is vibrating. For the leaf spring anti-torque system, the total axial resistance force is far less (19–243 N).
|Special Collections||International Workshop on Ice Drilling Technology Series, 7th International Workshop on Ice Drilling Technology|
|Equipment||Badger-Eclipse Drill, BPRC Intermediate Depth Drilling System, Deep Ice Sheet Coring (DISC) Drill, DSS/Law Dome Drill, EPICA/NGRIP Drill, FELICS, Hans Tausen Drill(s), Icelandic Temperate Glacier Drill, ISTUK Drill, JARE drills, KEMS / TELGA / TBZS drills, PICO 132 mm Drill, Rufli-Rand EM Drill, Shallow EM drills|
|Citation||Pavel Talalay , Xiaopeng Fan, Zhichuan Zheng, Jun Xue, Pinlu Cao, Nan Zhang, Rusheng Wang, Dahui Yu, Chengfeng Yu, Yunlong Zhang, Qi Zhang, Kai Su, Dongdong Yang, Jiewei Zhan ( 2014 ) Anti-torque systems of electromechanical cable-suspended drills and test results. Annals of Glaciology , 55 , 68 , 207-218 . doi: 10.3189/2014AoG68A025|