US3994338A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrostatic pressure release for bottom hole oil well pumps
Assignee: Individual
•
Filing: 1975-11-17
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Granted: 1976-11-30
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Expires: 1995-11-17
Abstract
Abstract A subjoint, having a wall port normally closed by a frangible disk, is connected with the depending end of a bottom hole oil well pump below the standing valve for draining fluid out of the tubing when the frangible disk is ruptured.
Inventors
- 👤 Richard E. Hix
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:56
CPC Classifications
F; F04; F04B; F04B53/00; F04B53/04; E; E21; E21B; E21B34/00; E21B34/06; E21B34/063
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
109 words
In combination with oil well downhole pumping equipment including a string of tubing having a hold down means at its depending end and having a pump disposed within the tubing and secured to the hold down means and forming a pump intake fluid passageway within the annular fluid area of the depending end portion of the tubing, the improvement comprising: a subjoint interposed between said pump and said hold down means and forming a continuation of said fluid passageway, said subjoint having a port in its wall providing communication between the intake fluid passageway and the tubing annular fluid area; and, frangible disk means normally closing the subjoint port.
Claim 2
Dependent Claim
109 words
In combination with oil well downhole pumping equipment including a string of tubing having a hold down means at its depending end and having a pump disposed within the tubing and secured to the hold down means and forming a pump intake fluid passageway within the annular fluid area of the depending end portion of the tubing, the improvement comprising: a subjoint interposed between said pump and said hold down means and forming a continuation of said fluid passageway, said subjoint having a port in its wall providing communication between the intake fluid passageway and the tubing annular fluid area; and, frangible disk means normally closing the subjoint port.
Claim 3
Dependent Claim
73 words
The combination according to claim 1 in which the subjoint wall around the port is characterized by a counterbore forming an annular shoulder facing inwardly toward the longitudinal axis of the intake fluid passageway and said frangible disk means includes: a metallic disk, adapted to rupture in response to a predetermined pressure differential across the wall of the subjoint, seated on the annular shoulder; and, a ring maintaining said disk within the counterbore.
Claim 4
Dependent Claim
31 words
The combination according to claim 1 and further including: a tube interposed between said subjoint and the tubing hold down means, said tube having left hand threads at its depending end.
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) | 1979-11-30 | 1980-05-31 | 1980-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-30 | 1984-05-31 | 1984-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-30 | 1988-05-31 | 1988-11-30 | $7700.00 | Window Closed / Lapsed |