Abnormal Torque with increasing RPM upto 150

During drilling a vertical 8½" well-bore with rotary BHA, while increasing the RPM from 120 to 150, the drilling torque will increase abnormally more than 10 klb-ft in open hole.

However, we have to check  the torque in 9⅝" csg and the same results happened in the cased hole. what is the most possible reason for this case.

Is this a problem with Topdrive bearing?

Thanks

9 Answer(s)

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