US3563323A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for borehole drilling
Assignee: Rolls Royce PLC
•
Filing: 1969-01-17
•
Granted: 1971-02-16
•
Expires: 1989-01-17
Abstract
Abstract In deviation borehole drilling with a down-hole motor a plurality of flexible collars is disposed in the drill string between the main stand of weight collars and the deviation assembly. In this way the bending moments of the main stand of weight collars are not transmitted to the down-hole motor and better control of deviation is achieved.
Inventors
- 👤 Howard Trethewen Edgecombe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:20
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/04; E21B7/06; E21B7/068
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
130 words
A drill string for use in deviation drilling with a down-hole motor comprising a deviation assembly, at least one flexible collar connected above the deviation assembly, a second collar connected above said at least one flexible collar, said at least one flexible collar being sufficiently flexible to substantially prevent the second collar from exerting a bending moment on the deviation assembly, but at the same time being capable of transmitting axial loads from the second collar to the deviation assembly, the deviation assembly further comprising, from its lower end, a drill bit, a down-hole motor, a bent sub, and a plurality of drill collars, which are sufficient to provide the necessary bending moment about the bent sub to produce the required side load on the drill bit for deviation thereof.
Claim 2
Dependent Claim
130 words
A drill string for use in deviation drilling with a down-hole motor comprising a deviation assembly, at least one flexible collar connected above the deviation assembly, a second collar connected above said at least one flexible collar, said at least one flexible collar being sufficiently flexible to substantially prevent the second collar from exerting a bending moment on the deviation assembly, but at the same time being capable of transmitting axial loads from the second collar to the deviation assembly, the deviation assembly further comprising, from its lower end, a drill bit, a down-hole motor, a bent sub, and a plurality of drill collars, which are sufficient to provide the necessary bending moment about the bent sub to produce the required side load on the drill bit for deviation thereof.
Claim 3
Dependent Claim
27 words
A drill string according to claim 1 and in which a ram is provided in the deviation assembly for providing an axial load on the drill bit.
Claim 4
Dependent Claim
27 words
A drill string as claimed in claim 1 and in which a ram is disposed in the deviation assembly between the down-hole motor and the bent sub.
Claim 5
Dependent Claim
17 words
A drill string as claimed in claim 1 and in which the down-hole motor is a turbodrill.
References Cited (Backward Citations)
US2336338A
Cited
US2500267A
Cited
US2565794A
Cited
US2805840A
Cited
US2829864A
Cited
US3380543A
Cited
US3476196A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |