US4386664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for guiding rotary drill
Assignee: Consolidation Coal Co
•
Filing: 1980-06-26
•
Granted: 1983-06-07
•
Expires: 2000-06-26
Abstract
Abstract A method of controlling the direction of a generally horizontal borehole drilled with a rotary drilling unit in a subterranean formation such as a coal seam. The method comprises predetermining drilling conditions for the formation being drilled and the equipment being utilized which will provide an upward buildup to the borehole trajectory, a downward change in trajectory, or a substantially level borehole trajectory. The predetermined conditions include the number of drill bit revolutions per unit length of borehole drilled. Periodic borehole surveys indicate to an operator which set of drilling conditions should be utilized for the next increment of hole drilled to maintain the hole within the boundaries of the formation being drilled.
Inventors
- 👤 Thomas R. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:43
CPC Classifications
E; E21; E21B; E21B47/00; E21B47/02; E21B47/022; E21B7/00; E21B7/04; E21B7/046
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
202 words
A method of controlling the direction of a generally horizontal borehole being drilled with a rotary drilling unit in a subterranean formation such as a coal seam comprising: (a) predetermining a set of drilling conditions for the formation being drilled and the equipment being utilized which will provide a substantially level borehole trajectory, said conditions including the number of drill bit revolutions per unit length of borehole drilled; (b) predetermining a set of drilling conditions for the formation being drilled and the equipment being utilized which will provide an upward change in borehole trajectory, said conditions including the number of drill bit revolutions per unit length of borehole drilled; (c) predetermining a set of drilling conditions for the formation being drilled and the equipment being utilized which will provide a downward change in borehole trajectory, said conditions including the number of drill bit revolutions per unit length of borehole drilled; (d) determining the trajectory of the borehole being drilled and the borehole position relative to the upper or lower boundary of said formation; and (e) drilling a portion of said borehole utilizing one of the predetermined sets of conditions to maintain the borehole within the upper and lower boundaries of said formation.
Claim 2
Independent Claim
202 words
A method of controlling the direction of a generally horizontal borehole being drilled with a rotary drilling unit in a subterranean formation such as a coal seam comprising: (a) predetermining a set of drilling conditions for the formation being drilled and the equipment being utilized which will provide a substantially level borehole trajectory, said conditions including the number of drill bit revolutions per unit length of borehole drilled; (b) predetermining a set of drilling conditions for the formation being drilled and the equipment being utilized which will provide an upward change in borehole trajectory, said conditions including the number of drill bit revolutions per unit length of borehole drilled; (c) predetermining a set of drilling conditions for the formation being drilled and the equipment being utilized which will provide a downward change in borehole trajectory, said conditions including the number of drill bit revolutions per unit length of borehole drilled; (d) determining the trajectory of the borehole being drilled and the borehole position relative to the upper or lower boundary of said formation; and (e) drilling a portion of said borehole utilizing one of the predetermined sets of conditions to maintain the borehole within the upper and lower boundaries of said formation.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein the borehole position and trajectory are periodically determined, and one of the predetermined sets of conditions is utilized after each periodic determination.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-06 | 1986-12-06 | 1987-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-06 | 1990-12-06 | 1991-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-06 | 1994-12-06 | 1995-06-07 | $7700.00 | Window Closed / Lapsed |