| 摘要 |
A drill bit suitable to be connected to a drill string for drilling a borehole into an earth formation, the drill string having a central longitudinal axis, the drill bit comprising a bit body connectable to the lower end of the drill string, and a cutting member provided with cutting devices at the outer surface thereof, the cutting member being rotatable relative to the bit body about a longitudinal axis of rotation extending eccentrically relative to the central longitudinal axis of the drill string, between a first rotational position[ and a second rotational position, whereby in said second rotational position the cutting devices arranged at a larger radial distance from the central longitudinal axis of the drill string than in said first rotational position.
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