US3603410A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for cavitational drilling utilizing periodically reduced hydrostatic pressure
Assignee: Mobil Oil AS
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Filing: 1968-12-05
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Granted: 1971-09-07
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Expires: 1988-12-05
Abstract
Abstract This specification discloses an improved method and apparatus for drilling a liquid-filled borehole into the earth with cavitational energy. The hydrostatic pressure at the borehole bottom is periodically reduced. Simultaneously, high frequency acoustic energy is imposed in the drilling liquid and cavitation is effected at least during the period of reduced hydrostatic pressure. The shock waves resulting from cavitation in the drilling liquid are utilized for drilling the borehole.
Inventors
- 👤 Frank A Angona
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:51
CPC Classifications
E; E21; E21B; E21B21/00; E21B21/08; E21B7/00; E21B7/24
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
24 words
The method of claim 1 wherein the frequency of said periodic reduction of hydrostatic pressure is less than the frequency of said acoustic field.
Claim 2
Independent Claim
96 words
A method of cavitationally drilling a borehole into the earth''s crust comprising: positioning an acoustic generator in the vicinity of the borehole bottom; circulating a drilling liquid downward through a drill string in said borehole and upward through the annulus defined by said drill string and the wall of said borehole; periodically reducing the hydrostatic pressure of said drilling liquid in the vicinity of said borehole bottom; and simultaneously operating said acoustic generator to produce an acoustic field in said drilling liquid in the vicinity of said borehole bottom to effect cavitation in said drilling liquid.
Claim 3
Dependent Claim
31 words
The method of claim 3 wherein said periodic reduction of hydrostatic pressure is effected by producing a second acoustic field within said drilling liquid in the vicinity of the borehole bottom.
Claim 4
Dependent Claim
23 words
The method of claim 4 wherein the frequency of said first-named acoustic field is greater than the frequency of said second acoustic field.
Claim 5
Dependent Claim
28 words
The method of claim 5 wherein the ratio of the frequency of said first-named acoustic field to the frequency of said second acoustic field is greater 5. 5.
Claim 6
Independent Claim
84 words
A method of cavitationally drilling a borehole into the earth''s crust comprising: circulating a drilling liquid downward through a drill string in said borehole and upward through the annulus defined by said drill string and the wall of said borehole; alternately supporting and releasing at least a portion of drilling liquid above the vicinity of the bottom of said borehole; and simultaneously producing an acoustic field in said drilling liquid in the vicinity of said borehole bottom of effect cavitation in said drilling liquid.
Claim 7
Independent Claim
131 words
A method of cavitationally drilling a borehole into the earth''s crust comprising: circulating a drilling liquid downward through a drill string in said borehole and upward through the annulus defined by said drill string and the wall of said borehole; periodically reducing the hydrostatic pressure of said drilling liquid in the vicinity of the borehole bottom by generating acoustic energy in said drill string at a point above the vicinity of said borehole bottom and transmitting said energy down said drill string to the vicinity of said borehole bottom thereby producing a first acoustic field within said drilling liquid in the vicinity of said borehole bottom; and simultaneously producing a second acoustic field in said drilling liquid in the vicinity of said borehole bottom to effect cavitation in said drilling liquid.
Claim 8
Dependent Claim
31 words
The method of claim 8 wherein said second acoustic field is generated by a radiating face and said acoustic energy generated in said drilL string is transmitted to the radiating face.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |