Well drilling collars
Abstract
Abstract A drill collar for rotary drilling carries a drill bit through which drilling fluid is ejected. The collar includes a cylindrical body having an axial through-bore therein for conducting drilling fluid. A pair of non-radially oriented passages are disposed in the body above the bit, each passage extending partially through the body and including an inner end terminating within the body adjacent the through-bore and an outer end opening into the ambient surroundings. The passages are spaced from the through-bore on opposite sides thereof. Conduits communicate the through-bore with the inner end of each of the passages to discharge drilling fluid through each passage and from the outer ends thereof to establish moments, all of which moments act to augment rotation of the collar. The through-bore is of reduced diameter below the passages to at least partially compensate for the pressure drop caused by the discharge through the passages. The total fluid energy emitted through the passages is in the range of from 1/4 to 1/3 of the total fluid energy discharged through the passages and drill bit.
Inventors
- 👤 Wylie Garrett
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-15 | 1984-12-15 | 1985-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-15 | 1988-12-15 | 1989-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-15 | 1992-12-15 | 1993-06-16 | $7700.00 | Window Closed / Lapsed |