Research Article
Study of Radial Vibration Impact on Friction and Torque of Rotary Drill String
Figure 5
Curves of the average of torque changing with . (a) Rotation speed Vr = 30 r/min. (b) Rotation speed Vr = 45 r/min. (c) Rotation speed Vr = 60 r/min.
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(b) |
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