US3881561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary bit for hydraulically drilling holes into underground formations
Assignee: Shell USA Inc
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Filing: 1974-02-25
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Granted: 1975-05-06
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Expires: 1994-02-25
Abstract
Abstract A jet rotary drill bit having a number of nozzles for jetting drilling fluid against the bottom of a well borehole, the centers of the jet nozzles being arranged in circles and at selected spaced intervals, and each nozzle having a central axis directed in a line to cross the central axis of the bit body at an angle other than 90*.
Inventors
- 👤 Albert C Pols
- 👤 Robijn Feenstra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:40
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/60
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
215 words
A rotary bit for hydraulically drilling holes into underground formations, said bit comprising a bit body having a central axis and a plurality of nozzles mounted in one end of the bit body, the centres of the outlet openings of the nozzles being arranged on circles concentric to the central axis, the distance between the intersections of adjoining circles with a plane through the central axis being not greater than 3/2 (d1 + d2), wherein d1 and d2 are the outlet diameters of the nozzles on these adjoining circles, each nozzle having a central axis crossing the central axis of the bit body at an angle other than 90* and being arranged tangetially to a separate mathematical cone having a central axis coinciding with the central axis of the bit body, said cone having the apex thereof above the end of the bit body in which the nozzles are mounted, the apex angles of adjoining cones not differing more than 14*, and the largest apex angle being over 90*, and wherein the apices of the mathematical cones line in a common point on the central axis of the rotary bit, said bit having a lower surface arcuate in form, the centres of the outlet openings of the nozzles being arranged in said arcuate lower surface.
Claim 2
Dependent Claim
215 words
A rotary bit for hydraulically drilling holes into underground formations, said bit comprising a bit body having a central axis and a plurality of nozzles mounted in one end of the bit body, the centres of the outlet openings of the nozzles being arranged on circles concentric to the central axis, the distance between the intersections of adjoining circles with a plane through the central axis being not greater than 3/2 (d1 + d2), wherein d1 and d2 are the outlet diameters of the nozzles on these adjoining circles, each nozzle having a central axis crossing the central axis of the bit body at an angle other than 90* and being arranged tangetially to a separate mathematical cone having a central axis coinciding with the central axis of the bit body, said cone having the apex thereof above the end of the bit body in which the nozzles are mounted, the apex angles of adjoining cones not differing more than 14*, and the largest apex angle being over 90*, and wherein the apices of the mathematical cones line in a common point on the central axis of the rotary bit, said bit having a lower surface arcuate in form, the centres of the outlet openings of the nozzles being arranged in said arcuate lower surface.
Claim 3
Dependent Claim
27 words
A rotary bit according to claim 1, comprising cutting elements for mechanically cutting the total surface of the bottom of a hole being drilled by the bit.
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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |