Patent US3568771A successfully refreshed from Google Patents.
US3568771A
Expired / Lapsed
US
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Method and apparatus for lifting foaming crude by a variable rpm submersible pump
Assignee: Centrilift Hughes Inc
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Filing: 1969-04-17
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Granted: 1971-03-09
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Expires: 1989-04-17
Abstract
Abstract Many oil wells, especially in their latter stage of primary or secondary recovery, produce foamy crude oil. This crude oil will vary from mostly liquid to mostly foam. Pumping such a fluid is rather difficult. The main difficulty is due to reduced bulk density of the fluids. Thus, a constant r.p.m. submersible centrifugal pump has very low efficiency. This invention controls the r.p.m. as a function of the bulk density of the crude in the well bore. Various means of obtaining this are given.
Inventors
- 👤 Renic P Vincent
- 👤 Eldon L Drake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:35
CPC Classifications
F; F04; F04D; F04D31/00; E; E21; E21B; E21B43/00; E21B43/12; E21B43/121; E21B43/128; F04D13/00; F04D13/02; F04D13/06; F04D13/08; F04D13/10; F04D15/00; F04D15/0066
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
45 words
A method of producing a foamy petroleum fluid from a well bore with a variable speed, centrifugal pump which comprises: measuring a parameter of the fluid in said well bore; and controlling the revolutions per minute of said centrifugal pump according to the parameter measured.
Claim 2
Dependent Claim
25 words
A method as defined in claim 2 in which the parameter measured is a measure of the density of the fluid in the well bore.
Claim 3
Dependent Claim
29 words
A method as defined in claim 2 in which the parameter measured is a measure of the difference in pressure at two vertically spaced points in said well bore.
Claim 4
Independent Claim
65 words
A method of producing foamy petroleum fluid from a well bore with a variable speed pump, which comprises: producing the foamy petroleum fluid through an oil-gas separator to separate the oil from the gas; measuring the rate of the flow of oil from said separator; and varying the rate of speed of said pump inversely to the rate of oil produced downstream from said separator.
Claim 5
Independent Claim
63 words
An apparatus for producing a foamy petroleum fluid from a well bore, which comprises: a variable speed, centrifugal pump located in said well bore; conduit means extending from said pump to the surface; means for measuring a parameter of the fluid in the well bore; and means responsive to the parameter thus measured for controlling the revolutions per minute of said centrifugal pump.
Claim 6
Dependent Claim
19 words
An apparatus as defined in claim 6 in which the means for measuring a parameter includes density measuring means.
Claim 7
Dependent Claim
43 words
An apparatus as defined in claim 6 in which the means for measuring the parameter includes two vertically spaced apart pressure sensors positioned in the petroleum fluid in the well bore and means for obtaining the differential pressure between the two pressure sensors.
Claim 8
Independent Claim
85 words
An apparatus for producing foamy petroleum fluid from a well bore, which comprises: a variable speed pump suspended in said well bore; an oil-gas separator located on the surface; conduit means connecting the discharge of said pump to said oil-gas separator; second conduit means for removing the oil from said Separator; means for measuring the rate of flow of oil through said second conduit; and means for varying the speed of said pump inversely to the rate of oil thus measured in said second conduit.
Claim 9
Independent Claim
126 words
An apparatus for producing a foamy petroleum fluid from a well bore, which comprises: a variable speed, electrically driven, centrifugal pump supported in said foamy fluid in said well bore, the speed of said pump being dependent on the frequency of the electrical current supplied thereto; an AC electrical power source; a frequency changer electrically connected to said power source, the output of said converter electrically connected to said pump; measuring means for obtaining a parameter which is a function of the density of the fluid being pumped; means connecting the measuring means to said frequency changer for adjusting the output frequency as an inverse function of the parameter obtained by said measuring means; and a fluid-carrying conduit extending from said pump to the surface. representing
Claim 10
Dependent Claim
56 words
An apparatus as defined in claim 10 in which said measuring means includes two vertically spaced pressure sensors submerged in the fluid signal within said well bore in the vicinity of said pump, and means using a signal representing the difference in pressure between said pressure sensors to control the frequency output of said frequency changer.
Claim 11
Dependent Claim
73 words
An apparatus as defined in claim 10 in which said measuring means includes a discharge conduit connected to said fluid-carrying conduit, an orifice plate having an orifice therein and placed within said discharge conduit; and Delta p means measuring the pressure drop across said orifice plate, said Delta p means including means to adjust the frequency output of said frequency changer as an inverse function of the pressure drop across said orifice plate.
Claim 12
Dependent Claim
23 words
An apparatus as defined in claim 10 in which said measuring means includes a mass flow meter fluidly connected to said fluid-carrying conduit.
Claim 13
Independent Claim
55 words
An apparatus for producing foamy petroleum crude from a well bore comprising a variable speed centrifugal pump, first means for measuring a parameter of the well fluid indicative of the density of the fluid, and means connected to said pump for varying said speed thereof in response to the parameter measured by said first means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |