Patent US4669522A successfully refreshed from Google Patents.
US4669522A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of rotary drill bits
Assignee: NL Petroleum Products Ltd
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Filing: 1986-04-01
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Granted: 1987-06-02
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Expires: 2006-04-01
Abstract
Abstract A method of making a rotary drill bit comprises forming a hollow mould for moulding at least a portion of the bit body, packing at least a part of the mould with powdered matrix material, and infiltrating the material with a metal alloy in a furnace to form a matrix, the alloy being a copper based alloy containing phosphorus and being selected to provide an infiltration temperature which is not greater than 850° C. and preferably not greater than 750° C.
Inventors
- 👤 Nigel D. Griffin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:06
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; B; B22; B22F; B22F3/00; B22F3/24; B22F3/26; B22F7/00; B22F7/06
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
74 words
A method of making a rotary drill bit comprising forming a hollow mould for moulding at least a portion of the bit body, packing at least a part of the mould with powdered matrix material, and infiltrating the material with a metal alloy in a furnace to form a matrix, the alloy being a copper based alloy containing phosphorus and being selected to provide an infiltration temperature which is not greater than 850° C.
Claim 2
Independent Claim
74 words
A method of making a rotary drill bit comprising forming a hollow mould for moulding at least a portion of the bit body, packing at least a part of the mould with powdered matrix material, and infiltrating the material with a metal alloy in a furnace to form a matrix, the alloy being a copper based alloy containing phosphorus and being selected to provide an infiltration temperature which is not greater than 850° C.
Claim 3
Dependent Claim
23 words
A method according to claim 1, wherein the alloy is selected to provide an infiltration temperature which is not greater than 750° C.
Claim 4
Dependent Claim
15 words
A method according to claim 1, wherein the alloy is an essentially two-element copper-phosphorus alloy.
Claim 5
Dependent Claim
14 words
A method according to claim 3, wherein the alloy is substantially of eutectic composition.
Claim 6
Dependent Claim
17 words
A method according to claim 4, wherein the alloy comprises approximately 8.4% phosphorus in a copper base.
Claim 7
Dependent Claim
13 words
A method according to claim 1, wherein the alloy is a copper-phosphorus-tin alloy.
Claim 8
Dependent Claim
22 words
A method according to claim 6, wherein the alloy comprises approximately 85% copper, up to 10% tin and up to 10% phosphorus.
Claim 9
Dependent Claim
13 words
A method according to claim 1, wherein the alloy is a copper-phosphorus-silver alloy.
Claim 10
Dependent Claim
19 words
A method according to claim 8, wherein the alloy includes up to 8% phosphorus and up to 20% silver.
Claim 11
Dependent Claim
13 words
A method according to claim 9, wherein the alloy includes approximately 2% silver.
Claim 12
Dependent Claim
18 words
A method according to claim 1, wherein the infiltration in the furnace is effected in a hydrogen atmosphere.
Claim 13
Dependent Claim
19 words
A method according to claim 11, wherein the hydrogen atmosphere has a dew point not greater than -30° C.
Claim 14
Dependent Claim
17 words
A method according to claim 1, wherein the infiltration in the furnace is effected in a vacuum.
Claim 15
Dependent Claim
46 words
A method according to claim 1, including the step of locating a plurality of cutting elements on the internal surface of the hollow mould before the mould is packed with matrix material, whereby the cutting elements become secured at the surface of the finished bit body.
Claim 16
Dependent Claim
51 words
A method according to claim 1, including the step of locating a steel blank within the hollow mould, before packing the mould around part of the steel blank with powdered matrix material, the steel blank being preformed with a threaded shank which constitutes the threaded shank of the finished drill bit.
References Cited (Backward Citations)
JPS55117543A
Cited
US4485147A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-01 | 1990-12-01 | 1991-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-01 | 1994-12-01 | 1995-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-01 | 1998-12-01 | 1999-06-02 | $7700.00 | Window Closed / Lapsed |