Patent ID: 6607046
Filing Date: 2003-08-19
Classification: E21B

Abstract:
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 means 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 second rotational position, whereby in said second rotational position the cutting means is arranged at a larger radial distance from the central longitudinal axis of the drill string than in said first rotational position, wherein the cutting member is movable in an axial direction relative to the bit body between a primary axial position and a secondary axial position, wherein in the primary axial position the cutting member is located closer to the lower end of the drill bit than in the secondary axial position.