US4484960A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-temperature-stable ignition powder
Assignee: ETI EXPLOSIVES TECHNOLOGIES INTE
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Filing: 1983-11-15
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Granted: 1984-11-27
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Expires: 2003-11-15
Abstract
Abstract A mixture of about from 60 to 40 percent amorphous boron and about from 94 to 60 percent ferric oxide, useful as an ignition composition for electrically actuated blasting caps and squibs, has outstanding thermal stability, i.e., up to about 500° C. making it especially suitable for use in blasting caps in oil wells that are deep and hot, e.g., in the liquid-disabled cap described in U.S. patent application Ser. No. 469,954. Bridgewire-sensitive compositions containing about from 10 to 20 percent boron are preferred. The compositions can be self-grained, or they may be grained preferably with a water-soluble polymeric binder.
Inventors
- 👤 Klaus G. Rucker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:35
CPC Classifications
F; F42; F42B; F42B3/00; F42B3/10; F42B3/192; C; C06; C06B; C06B33/00; C06C; C06C7/00; F42B3/12; F42B3/125
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
26 words
An ignition powder for electrically actuated initiation devices comprising a mixture of boron and ferric oxide in about a 6/94 to 40/60 parts ratio by weight.
Claim 2
Dependent Claim
26 words
An ignition powder for electrically actuated initiation devices comprising a mixture of boron and ferric oxide in about a 6/94 to 40/60 parts ratio by weight.
Claim 3
Dependent Claim
20 words
An ignition powder of claim 1 wherein the boron/ferric oxide ratio is about from 10/90 to 20/80 parts by weight.
Claim 4
Dependent Claim
16 words
An ignition powder of claim 2 wherein said mixture is substantially free of a graining agent.
Claim 5
Dependent Claim
23 words
An ignition powder of claim 2 containing up to about 2 percent by weight of a water-soluble polymeric binder as a graining agent.
Claim 6
Dependent Claim
29 words
An ignition powder of claim 2 in the ignition assembly of an electric blasting cap or squib and having embedded therein a 0.04 to 0.2 mm thick nickel-chrome bridgewire.
References Cited (Backward Citations)
US2717204A
Cited
US3865035A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-27 | 1988-05-28 | 1988-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-27 | 1992-05-28 | 1992-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-27 | 1996-05-28 | 1996-11-27 | $7700.00 | Window Closed / Lapsed |