US4170513A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of tungsten carbide from scrap mining bits
Assignee: Piche Fernand Enterprises Ltd
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Filing: 1978-06-06
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Granted: 1979-10-09
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Expires: 1998-06-06
Abstract
Abstract Tungsten carbide inserts are recovered from scrap mining bits by treatment in a sulphuric acid bath to eat away part of the steel surrounding the inserts and then heating the bit and vibrating the heated bit to knock out the inserts. In a modification used on cross-type bits, heat and vibration alone are used.
Inventors
- 👤 Fernand J. Piche
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:26
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/28; C22; C22B; C22B7/00; C23F1/02; Y; Y02; Y02P; Y02P10/00; Y02P10/20; Y10; Y10S; Y10S156/00; Y10S156/918; Y10S156/919; Y10T; Y10T156/00; Y10T156/11
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
90 words
A method for the recovery of tungsten carbide inserts from worn steel drilling bits, which comprises: subjecting said bits to acid treatment in an acid treatment bath for a time at least sufficient to eat away any turned over burrs from around said inserts, heating said acid treated bits to an elevated temperature at least sufficient to loosen said inserts within their sockets in said bits so that they may be removed by strong vibration, and subjecting the heated bits to strong vibration to dislodge said inserts from their sockets.
Claim 2
Independent Claim
90 words
A method for the recovery of tungsten carbide inserts from worn steel drilling bits, which comprises: subjecting said bits to acid treatment in an acid treatment bath for a time at least sufficient to eat away any turned over burrs from around said inserts, heating said acid treated bits to an elevated temperature at least sufficient to loosen said inserts within their sockets in said bits so that they may be removed by strong vibration, and subjecting the heated bits to strong vibration to dislodge said inserts from their sockets.
Claim 3
Dependent Claim
36 words
The method of claim 1 wherein said acid treatment is effected for a period sufficient to eat steel away from said inserts so that they project from the bit surface upon completion of said acid treatment.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said acid treatment is effected using sulphuric acid.
Claim 5
Dependent Claim
18 words
The method of claim 1, 2 or 3, wherein said acid treatment is effected at an elevated temperature.
Claim 6
Dependent Claim
25 words
The method of claim 1, 2 or 3, wherein said acid treatment is effected at an elevated temperature of about 150° to about 200° F.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein said elevated temperature to which said acid treated bits is heated is at least about 1600° F.
Claim 8
Dependent Claim
30 words
The method of claim 1 or 6 wherein said strong vibration to which the heated bits are subjected may be achieved by striking the heated bits with a jack hammer.
Claim 9
Dependent Claim
23 words
The method of claim 5 wherein said elevated temperature to which said acid treated bits is heated is at least about 1600° F.
Claim 10
Dependent Claim
28 words
The method of claim 8 wherein said strong vibration to which the heated bits are subjected may be achieved by striking the heated bits with a jack hammer.
Claim 11
Dependent Claim
17 words
The method of claim 1 or 6 wherein said drilling bits are tricones or split roller bits.
Claim 12
Dependent Claim
15 words
The method of claim 5 wherein said drilling bits are tricones or split roller bits.
Claim 13
Dependent Claim
15 words
The method of claim 7 wherein said drilling bits are tricones or split roller bits.
Claim 14
Independent Claim
45 words
A method for the recovery of tungsten carbide inserts from worn steel drilling cross-bits, which comprises: heating said bits to an elevated temperature at least sufficient to loosen said inserts from within their sockets in said bits, and removing said loosened inserts from their sockets.
Claim 15
Independent Claim
45 words
A method for the recovery of tungsten carbide inserts from worn steel drilling cross-bits, which comprises: heating said bits to an elevated temperature at least sufficient to loosen said inserts from within their sockets in said bits, and removing said loosened inserts from their sockets.
Claim 16
Dependent Claim
43 words
The method of claim 13 including heating said bits in a rotary kiln at an elevated temperature of at least about 1300° C. and ejecting the heated bits from the kiln onto a grate through which the removed inserts fall into a receptacle.
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) | 1982-10-08 | 1983-04-09 | 1983-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-08 | 1987-04-09 | 1987-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-08 | 1991-04-09 | 1991-10-09 | $7700.00 | Window Closed / Lapsed |