摘要 |
The assembly comprise a bent sub (1411), and optionally a swivel (1480). The bend angle a of the bent sub in relation to the central axis of the assembly can be adjusted by rotating lower bend member (1431) relative to upper bend member (1430), which is non-rotatably attached to downhole motor (1460), using harmonic drive (1413) arranged between lower and upper bend members. In order to adjust the rotational orientation of the bent sub (1411), a swivel (1480) is provided having upper and lower swivel members (1432, 1433). Upper swivel member can be rotated relative to lower member, which is non-rotatably attached to the downhole motor, using a second harmonic drive (1423) arranged between lower and upper swivel members. |