Continuous on-bottom directional drilling method and system

A method of drilling a bore hole, comprising:

• advancing a drill string having a steerable drilling motor connected thereto in said bore hole, said steerable drilling motor having a tool face angle, said drill string having a bit at a bottom end thereof, said bit being in substantially continuous contact with a bottom of said well bore, thereby drilling in a sliding mode;
• rotating said drill string and continuing to advance said drill string with said bit in substantially continuous contact with said bottom after drilling in said sliding mode, thereby drilling in a rotary mode;
• and
• rocking said drill string in said sliding mode.

A method of directional drilling, which comprises:

• (a) orienting a steerable drilling motor at a target tool face angle, said steerable drilling motor being connected by a drill string to a surface drilling location;
• (b) rocking said drill string by:
• (i) rotating said drill string at said surface location in a first direction until a first torque magnitude is reached at said surface location substantially without changing a tool face angle of said steerable drilling motor;
• and
• (ii) rotating said drill string at said surface location in a second direction opposite said first direction until a second torque magnitude is reached without changing the face angle of said steerable drilling motor;
• and
• (c) maintaining the tool face angle of said steerable drilling motor at said target tool face angle by adjusting at least one of said first and second torque magnitudes for least one drill string rotation in the first and second direction.

A directional drilling system, which comprises:

• a steerable drilling motor;
• a steering tool operatively coupled to said steerable drilling motor, said steering tool being adapted to produce a tool face angle signal;
• a drill string coupled to said steerable drilling motor;
• a drill string torque sensor operatively coupled to said drill string, said torque sensor being adapted to produce a drill string torque signal;
• means for rotating said drill string at a surface location;
• a controller for operating said rotating means to rotate said drill string cyclically back and forth in a first direction until a first torque magnitude is reached and then in a second direction opposite said first direction until a second torque magnitude is reached;
• and,
• a bump control for adjusting at least one of said first and second torque magnitudes for at least one cycle.

A method for directional drilling, comprising:

• advancing a drill string including a bit and a drilling motor thereon along a bore hole, the drilling motor oriented at a selected tool face angle;
• rotating the drill string in a first direction until a first torque magnitude is reached;
• rotating the drill string in a second direction opposite to the first direction until a second torque magnitude is reached;
• reducing a rate of release of the drill string into the bore hole;
• repeating rotating the drill string in the first direction to a torque value increased by a selected amount above the previous torque magnitude in the first direction;
• and
• repeating the rotating the drill string in the second direction, rotating attain in the first direction and increasing the torque until the drill string rotates substantially continuously in the first direction.

A method of drilling a bore hole, comprising:

• advancing a drill string having a steerable drilling motor connected thereto in said bore hole, said steerable drilling motor having a tool face angle, said drill string having a bit at a bottom end thereof, said bit being in substantially continuous contact with a bottom of said well bore, thereby drilling in a sliding mode;
• rocking said drill string in said sliding mode;
• and
• maintaining said steerable drilling motor at a target tool face angle when drilling in said sliding mode.