US3713393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Igniter mechanism for solid propellants under high fluid head
Assignee: BP America Production Co
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Filing: 1970-04-02
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Granted: 1973-01-30
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Expires: 1990-04-02
Abstract
Abstract An igniter is describe capable of operating at high bottomhole pressures, i.e., greater than 2,000 psi. To prevent the influx of well fluids into the recess which has been drilled into a portion of the main propellant, it is filled with a plastic or viscous propellant. A flame squib or resistance wire is immersed in the viscous propellant. Any pressure exerted by well fluids against the viscous propellant serves to force it into void spaces around the flame squib thus protecting the squib as well as the surrounding primary propellant from direct contact with aqueous well fluids.
Inventors
- 👤 Connor D O
- 👤 C Fast
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:20
CPC Classifications
F; F42; F42B; F42B3/00; F42B3/10; F42B3/195; E; E21; E21B; E21B43/00; E21B43/11; E21B43/116; E21B43/1185; F42B3/12; F42B3/128
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
111 words
An igniter mechanism for a propellant charge enclosed in a plastic casing, said mechanism comprising, a chamber within said charge, a cavity within said chamber, an igniter means within said cavity, a plug in the exterior end of said chamber through which said igniter mechanism extends, and a flowable, plastic, rapid-burning propellant in said chamber in an amount sufficient to envelop said cavity and to substantially fill the remainder of said chamber so that when external pressure is applied to said plug such pressure is equalized by the plastic propellant in said chamber, thereby effecting a liquid-tight seal to prevent the movement of well fluids into contact with said igniter mechanism.
Claim 2
Dependent Claim
111 words
An igniter mechanism for a propellant charge enclosed in a plastic casing, said mechanism comprising, a chamber within said charge, a cavity within said chamber, an igniter means within said cavity, a plug in the exterior end of said chamber through which said igniter mechanism extends, and a flowable, plastic, rapid-burning propellant in said chamber in an amount sufficient to envelop said cavity and to substantially fill the remainder of said chamber so that when external pressure is applied to said plug such pressure is equalized by the plastic propellant in said chamber, thereby effecting a liquid-tight seal to prevent the movement of well fluids into contact with said igniter mechanism.
Claim 3
Dependent Claim
16 words
The igniter mechanism of claim 1, in which the igniter means is an electric flame squib.
Claim 4
Dependent Claim
19 words
The igniter mechanism of claim 2 wherein said squib has a built-in time delay of from about 100-500 milliseconds.
Claim 5
Dependent Claim
24 words
The igniter mechanism of claim 1, wherein the flowable, plastic, rapid-burning propellant is made of a mixture consisting essentially of nitrocellulose and nitrocellulose cement.
Claim 6
Dependent Claim
25 words
The igniter mechanism of claim 1 wherein the flowable, plastic, rapid-burning propellant is made of a mixture consisting essentially of smokeless powder and nitrocellulose cement.
Claim 7
Dependent Claim
16 words
The igniter mechanism of claim 4 wherein a pyroxylin lacquer is substituted for the nitrocellulose cement.
Claim 8
Dependent Claim
22 words
The igniter mechanism of claim 4 in which the two principal ingredients of said rapid-burning propellant are employed in substantially equal amounts.
Claim 9
Dependent Claim
31 words
The igniter mechanism of claim 1 in which means is provided for diverting from said chamber a minor portion of the gaseous combustion products resulting from ignition of said rapid-burning propellant.
Claim 10
Dependent Claim
22 words
The igniter mechanism of claim 5 in which the two principal ingredients of said rapid-burning propellant are employed in substantially equal amounts.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |