US3757878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill bits and method of producing drill bits
Assignee: Norton Christensen Inc
•
Filing: 1972-08-24
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Granted: 1973-09-11
•
Expires: 1992-08-24
Abstract
Abstract Earth boring drills such as are useful in oil well drilling or other drilling operations and methods of producing such drills in which metal-encapsulated primary abrasive particles such as diamonds and metal-encapsulated secondary particles are bonded together and to a metallic shank by means of a metal matrix.
Inventors
- 👤 A Wilder
- 👤 H Bridwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:03
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; B; B22; B22D; B22D19/00; B22D19/06; B22D19/14
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
15 words
In the drill bit of claim 1 in which the abrasive particles are tungsten-coated alumina.
Claim 2
Dependent Claim
25 words
The drill bit of claim 1 in which the metal encapsulating said abrasive particles is tungsten, or tantalum, or columbium (niobium) or molybdenum or titanium.
Claim 3
Dependent Claim
28 words
In the drill bit of claim 3, said abrasive particles in said coating are metal-encapsulated tungsten carbide, or metal-encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride.
Claim 4
Dependent Claim
47 words
The drill of claim 1 in which the coating extends over the crown end of said shank and at said crown end contains a metal-bonded mixture of diamond particles and particles of metal-encapsulated tungsten carbide, or metal encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride.
Claim 5
Dependent Claim
21 words
The drill of claim 5 in which the metal-encapsulated said particles is tungsten, or tantalum, or columbium, or molybdenum, or titanium.
Claim 6
Dependent Claim
15 words
In the drill bit of claim 5 in which the abrasive particles are tungsten-coated alumina.
Claim 7
Dependent Claim
49 words
The drill of claim 1 in which said coating extends over the crown end and contains a mixture of diamond particles and tungsten carbide particles and said coating above said crown is substantially free of diamond particles and contains metal-encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride.
Claim 8
Dependent Claim
21 words
The bit of claim 8 in which said encapsulating metal is tungsten, or tantalum, or columbium (niobium), or molybdenum, or titanium.
Claim 9
Dependent Claim
13 words
The drill of claim 8 in which the metal-encapsulated abrasive is tungsten-coated alumina.
Claim 10
Dependent Claim
71 words
The drill of claim 1 in which said coating extends over the crown end and the coating at said crown end contains a mixture of metal-encapsulated diamond particles and metal-encapsulated tungsten carbide, or metal-encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride and the coating above said crown is substantially free of diamond particles and contains metal-encapsulated tungsten carbide, or metal-encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride.
Claim 11
Dependent Claim
21 words
The drill of claim 11 in which said encapsulating metal is tungsten, or tantalum, or columbium (niobium), or molybdenum, or titanium.
Claim 12
Dependent Claim
23 words
The drill of claim 11 in which said encapsulating metal is tungsten and the metal-encapsulated abrasive particles other than diamonds are tungsten-encapsulateD alumina.
Claim 13
Dependent Claim
19 words
The drill of claim 1 in which the coating at the crown end of said shank includes diamond particles.
Claim 14
Dependent Claim
14 words
The drill bit of claim 14 in which the abrasive particles are tungsten-coated alumina.
Claim 15
Dependent Claim
25 words
The drill bit of claim 14 in which the metal encapsulating said abrasive particles is tungsten, or tantalum, or columbium (niobium), or molybdenum, or titanium.
Claim 16
Dependent Claim
25 words
The drill bit of claim 16 in which the metal encapsulating said abrasive particles is tungsten, or tantalum, or columbium (niobium) or molybdenum, or titanium.
Claim 17
Dependent Claim
27 words
The drill bit of claim 17, said abrasive particles in said coating are metal-encapsulated tungsten carbide, or metal-encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride.
Claim 18
Dependent Claim
43 words
The drill bit of claim 1 in which said coating extends over the crown end of said shank and in which diamond particles are surface set in said end in space configuration over the said end surface forming the crown of said bit.
Claim 19
Dependent Claim
25 words
The drill bit of claim 19 in which the metal encapsulating said abrasive particles is tungsten, or tantalum, or columbium (niobium) or molybdenum or titanium.
Claim 20
Dependent Claim
17 words
The drill of claim 19 in which the coating at said crown end contains metal-bonded tungsten carbide.
Claim 21
Dependent Claim
18 words
In the drill bit of claim 21 in which the coating above said crown end contains tungsten-coated alumina.
Claim 22
Dependent Claim
28 words
The drill of claim 21 in which the coating above said crown end contains metal-encapsulated tungsten carbide, or metal-encapsulated alumina, or metal-encapsulated silicon carbide, or metal-encapsulated boron nitride.
Claim 23
Dependent Claim
25 words
The drill bit of claim 23 in which the metal encapsulating said abrasive particles is tungsten, or tantalum, or columbium (niobium) or molybdenum or titanium.
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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) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |