Method and system of drilling deviated wellbores.

摘要

Directional drilling is carried out with a rotary drilling tool having a drill string 17, a drill bit 19, a drill motor 31 for rotating the drill bit independently of the drill string, an extension sub 32 having both axially contracted and axially extended positions for providing weight to the drill bit when moving from a contracted to an extended position so as to effect a drilling stroke by the drill bit into the wellbore bottom when drilling with the drill bit independently of rotation of the drill string and a bent sub affixed below the lower end of the drill string for angularly displacing the axes of the drill bit and extension sub from the axis of the drill string so as to effect a deviation of the wellbore.