Patent US4553615A successfully refreshed from Google Patents.
US4553615A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary drilling bits
Assignee: NL Industries Inc
•
Filing: 1983-02-17
•
Granted: 1985-11-19
•
Expires: 2003-02-17
Abstract
Abstract A rotary drilling drag bit for drilling from the surface deep holes in sub-surface formations e.g. for oil has a body (4) with a diameter of at least 100 mm and having a bore for passage of drilling fluid to its face (3) and rotatable cutting elements (6) having a cutting face comprising an agglomerate of diamond particles so mounted on the body (4) that they are free to rotate in use. The cutting elements are of long life and highly effective in drilling.
Inventors
- 👤 Alfred J. Grainger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:20
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; E21B10/56; E21B10/567; E21B10/08; E21B10/12; E21B10/18; E21B10/20; E21B10/22; E21B10/50; E21B10/62
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
193 words
A rotary drilling bit, for drilling, from the surface, deep holes in sub-surface formations, comprising a bit body with a face and a shank having a bore for the passage of drilling fluid to the face of the bit, the diameter of the body of the bit exceeding 100 mm, and a plurality of rotatable cutting elements, each of said cutting elements being in the form of a disc having a cutting face comprising an agglomerate of diamond particles in the form of a thin flat layer, bonded to a thicker backing layer of cemented tungsten carbide, each disc having a cylindrical spindle extending from the backing layer and rotatably mounted in a hole in an element set in the body of the bit, the axis of rotation of the spindle extending perpendicularly to the cutting face of the cutting element, said spindle, in a direction away from the cutting face, being inclined rearwardly with respect to the direction of rotation of the bit and in a direction away from the surface of the formation being cut by said cutting element, said cutting elements being free to rotate in use of the bit.
Claim 2
Dependent Claim
193 words
A rotary drilling bit, for drilling, from the surface, deep holes in sub-surface formations, comprising a bit body with a face and a shank having a bore for the passage of drilling fluid to the face of the bit, the diameter of the body of the bit exceeding 100 mm, and a plurality of rotatable cutting elements, each of said cutting elements being in the form of a disc having a cutting face comprising an agglomerate of diamond particles in the form of a thin flat layer, bonded to a thicker backing layer of cemented tungsten carbide, each disc having a cylindrical spindle extending from the backing layer and rotatably mounted in a hole in an element set in the body of the bit, the axis of rotation of the spindle extending perpendicularly to the cutting face of the cutting element, said spindle, in a direction away from the cutting face, being inclined rearwardly with respect to the direction of rotation of the bit and in a direction away from the surface of the formation being cut by said cutting element, said cutting elements being free to rotate in use of the bit.
Claim 3
Dependent Claim
23 words
A bit according to claim 1 in which the agglomerate is an agglomerate of diamond particles, secondary particles and a metallic bonding agent.
Claim 4
Dependent Claim
23 words
A bit according to claim 1 in which the diameter of the spindle is at least 45% of the diameter of the disc.
Claim 5
Dependent Claim
25 words
A bit according to claim 1 in which the element set in the body of the bit is a bush formed of cemented tungsten carbide.
Claim 6
Dependent Claim
22 words
A bit according to claim 4 in which there is a sleeve of low friction material in the bore of the bush.
Claim 7
Dependent Claim
17 words
A bit according to claim 4 in which the spindle is coated with a low friction material.
Claim 8
Dependent Claim
20 words
A bit according to claim 4 in which the inner face of the disc is coated with low friction material.
Claim 9
Dependent Claim
20 words
A bit according to claim 4 in which the outer face of the bush is coated with low friction material.
Claim 10
Dependent Claim
24 words
A bit according to claim 1 in which the element set in the body of the bit is in the form of a peg.
Claim 11
Dependent Claim
15 words
A bit according to claim 9 in which the peg is of cemented tungsten carbide.
Claim 12
Dependent Claim
13 words
A bit according to claim 9 is which the peg is of steel.
Claim 13
Dependent Claim
21 words
A bit according to claim 1 in which the cutting elements are mounted on the bit body at a side rake.
Claim 14
Dependent Claim
17 words
A bit according to claim 1 in which the diameter of the bit body exceeds 160 mm.
References Cited (Backward Citations)
US1790613A
Cited
US1723381A
Cited
US3763492A
Cited
US3720273A
Cited
US4073354A
Cited
US4200159A
Cited
US4222446A
Cited
US4350215A
Cited
US4201421A
Cited
US4396077A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-18 | 1989-05-20 | 1989-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-18 | 1993-05-20 | 1993-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-18 | 1997-05-20 | 1997-11-19 | $7700.00 | Window Closed / Lapsed |