Directional drilling apparatus
OwnerJohn D. Jeterinventor
Life of this patent
Estimating the term…
Abstract
A pendulum is mounted in the drill pipe close to the drill bit to assume a vertical position in the azimuthal plane of the drill pipe. When the position of the pendulum is such that the inclination of the drill pipe is not a preselected amount or the azimuthal direction of the pipe is not the preselected direction, a lateral force is imposed on the drill bit urging it to drill in a direction that will return the drill pipe to said preselected inclination or azimuthal direction. The pendulum and its associated apparatus is rotated in the direction opposite the direction that the drill pipe is rotated and at the same speed, so that the pendulum is substantially nonrotative relative to the earth.
Claims26
Apparatus for urging a drill bit connected to a drill string to drill through the earth in a preselected azimuthal direction comprising azimuthal direction sensing means located in the drill string, means responsive to the azimuthal direction sensing means when the azimuthal direction of the pipe string varies from the preselected direction for exerting a lateral force on the drill bit to urge the drill bit to drill in a direction that will return the drill string to the preselected azimuthal direction, and means for rotating the azimuthal direction sensing means relative to the drill string at approximately the speed of rotation of the drill string and in the opposite direction to hold the sensing means substantially non-rotative relative to the earth.
Apparatus for urging a drill bit connected to a drill string to follow a given angle from the vertical comprising, inclination sensing means located in the drill string to sense the angle the drill string makes with the vertical, means responsive to the inclination of the drill string to exert a lateral force on the drill bit, when the inclination is different from a preselected angle, to urge the bit to drill in a direction that will return the drill string to the preselected angle, and means for rotating the inclination sensing means at approximately the speed of rotation of the drill string and in the opposite direction to keep the sensing means substantially non-rotative relative to the earth.
Apparatus for urging a drill bit connected to a drill string to follow a given angle from the vertical comprising, inclination sensing means located in the drill string having a vertical seeking member that makes an angle with the drill string substantially equal to the angle the drill string makes with the vertical, means responsive to the angle the drill string makes with the vertical seeking member for exerting a lateral force on the drill bit, when the angle is different from a preselected angle, to urge the bit to drill in a direction that will return the drill string to the preselected angle, and means for rotating the inclination sensing means at approximately the speed of rotation of the drill string and in the opposite direction to keep the sensing means substantially non-rotative relative to the earth.
Apparatus for directionally drilling a well bore comprising a drill string extending into the well bore, a drill bit, means connecting the drill bit to the drill string to transmit rotation of the drill string to the drill bit and to allow limited universal pivotal movement of the bit around an axis perpendicular to the longitudinal axis of the drill string, including a bit sub having an upper portion extending above the universal connection into the drill string, means for sensing the inclination of the drill string adjacent the bit, and means responsive to the sensing means for urging the bit to pivot in the desired direction around said axis to change the direction of the well bore, said urging means including a piston mounted in the drill string adjacent the upper portion of the bit sub for rotation relative to the drill string and for axial movement along the longitudinal axis of the drill string toward and away from said upper portion for rotation relative thereto, a cam follower connected to the swivel member, a cam surface on the piston engaging the cam follower to pivot the sub and bit around said axis when the piston is moved axially along the longitudinal axis of the drill string, and means responsive to the sensing means to position the piston to pivot the sub and bit in the desired direction and to move the piston to so pivot the sub and bit.
Dependencies are inferred from the claim text.