Helical drilling apparatus, systems, and methods
AssigneeLongyear TM, Inc.
InventorsMichael D. Rupp, Christopher L. Drenth
Life of this patent
Estimating the term…
Abstract
A down-the-hole assembly includes a housing having a central axis and a mechanical gear box positioned within the housing. The mechanical gear box is coupled to the housing such that rotation of the housing at a first rotational rate provides a rotary input to the mechanical gear box. A rotary cutting bit is coupled to the mechanical gear box. The mechanical gear box is configured to rotate said rotary cutting bit at a second rotational rate in response to that rotary input from the housing. The second rotational rate is greater than the first rotational rate. The mechanical gear box is also further configured to cause the rotary cutting bit to orbit about the central axis of the housing.
Claims23
A down-the-hole assembly, comprising:
- a housing having a central axis;
- a mechanical gear box positioned within said housing, said mechanical gear box further being coupled to said housing such that rotation of said housing at a first rotational rate provides a rotary input to said mechanical gear box, wherein said mechanical gear box includes:
- a ring gear operatively associated with said housing,
- a bit gear operatively associated with said ring gear, and
- a grounding ring operatively associated with said bit gear;
- an isolation mechanism for separating rotation of said housing from said grounding ring;
- and
- a rotary cutting bit coupled to said mechanical gear box, said mechanical gear box being configured to rotate said rotary cutting bit at a second rotational rate in response to said rotary input from said housing, said second rotational rate being greater than said first rotational rate, said mechanical gear box being further configured to cause said rotary cutting bit to orbit about said central axis of said housing.
A down-the-hole drilling assembly adapted to be secured to a drill string that is rotated by a drill rig, comprising:
- a housing having a central axis, said housing being adapted to be coupled and rotationally fixed to the drill string;
- a mechanical gear box positioned at least partially inside said housing;
- and
- a rotary cutting bit coupled to said mechanical gear box;
- wherein rotation of the drill string at a first rotational rate causes said housing to rotate at said first rotational rate thereby causing said mechanical gear box to rotate said rotary cutting bit at a second rotational rate, said second rotational rate being greater than said first rotational rate;
- said mechanical gear box being further adapted to cause said rotary cutting bit to orbit about said central axis of said housing.
A down-the-hole drilling assembly adapted to be secured to a drill string that is rotated by a drill rig, comprising:
- a housing defining a lumen having a central axis, said housing being adapted to be coupled and rotationally fixed to the drill string;
- a ring gear formed on an inner surface of said housing, said ring gear being in communication with said lumen;
- a first gear operatively associated with said ring gear;
- a second gear operatively associated with said ring gear;
- a third gear operatively associated with each of said first gear and said second gear;
- said third gear further being positioned at least partially between said first gear and said second gear;
- and
- a rotary cutting bit coupled to said first gear, wherein rotation of the drill string at a first rotational rate causes said housing to rotate at said first rotational rate thereby causing said first gear to rotate at a second rotational rate, said second rotational rate being greater than said first rotational rate and wherein said rotation of said housing causes said first gear and said rotary cutting bit to orbit about the central axis.
A method of drilling, comprising:
- coupling a helical drilling device to a drill string by rotationally fixing a housing of said helical drilling device to said drill string, said helical drilling device including a mechanical gear box positioned within a housing and a rotary cutting bit coupled to said mechanical gear box,
- positioning said rotary cutting bit in a bore hole in a formation, said bore hole having a face diameter, wherein said rotary cutting bit has a diameter less than said face diameter;
- rotating said drill string at a first rotational rate thereby by causing said housing to rotate at said first rotational rate;
- wherein rotation of said housing at said first rotational rate causes said mechanical gear box to rotate said rotary cutting bit at a cutting rotational rate greater than said first rotational rate;
- and
- orbiting the rotary cutting bit to drill the face diameter in response to rotation of said drill string.
Dependencies are inferred from the claim text.