US4736623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Leak detector
Assignee: BP Corp North America Inc
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Filing: 1987-03-30
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Granted: 1988-04-12
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Expires: 2007-03-30
Abstract
Abstract The leak detector is utilized for determining the presence of a leak in an above ground tank of liquid having a lower specific gravity and a lower electrical or thermal conductivity than water. The leak detector includes a device for determining the level of water in the tank and a mechanism for sensing changes in the level of water in the tank over time. A leak detecting system utilizing the leak detector will also include an apparatus for determining the amount and rate of leakage relative to the capacity of the tank and the change of the level of the water in the tank over a selected time period.
Inventors
- 👤 Arthur R. Brown
- 👤 David C. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 03:11
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/26; G01M3/32; G01M3/3236; G01M3/3245; G01F; G01F23/00; G01F23/22; G01F23/24; G01F23/241
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
82 words
A leak detector for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank and second means for sensing a change in the level of water in the tank including means for sensing changes in conductivity at points along a line extending across an interface between the liquid hydrocarbons and the water in the tank.
Claim 2
Dependent Claim
82 words
A leak detector for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank and second means for sensing a change in the level of water in the tank including means for sensing changes in conductivity at points along a line extending across an interface between the liquid hydrocarbons and the water in the tank.
Claim 3
Dependent Claim
108 words
A leak detector for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank, second means for sensing a change in the level of water in the tank including means for sensing changes in conductivity at points along a line extending across an interface between the liquid hydrocarbons and the water in the tank, and third means for determining the rate of leakage relative to the capacity of the tank and the change of the level of water in the tank.
Claim 4
Dependent Claim
108 words
A leak detector for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank, second means for sensing a change in the level of water in the tank including means for sensing changes in conductivity at points along a line extending across an interface between the liquid hydrocarbons and the water in the tank, and third means for determining the rate of leakage relative to the capacity of the tank and the change of the level of water in the tank.
Claim 5
Dependent Claim
14 words
The leak detector of claim 2 wherein said third determining means comprises a microprocessor.
Claim 6
Dependent Claim
161 words
A leak detector for determined a bottom leak in an above for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank including an eleongate body connected to a cable which can be used to lower said body into the tank from the top thereof to place said body on the bottom of the tank in an upright position said body having a generally vertical layer of water sensing material on the outer surface thereof such taht when the body is partly in water and partly in liquid the portion of the layer in the water will change color to provide an indication or the level of water in the tank when the body is withdrawn from the tank, and second means for sensing a change in the level of water in the tank.
Claim 7
Dependent Claim
161 words
A leak detector for determined a bottom leak in an above for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank including an eleongate body connected to a cable which can be used to lower said body into the tank from the top thereof to place said body on the bottom of the tank in an upright position said body having a generally vertical layer of water sensing material on the outer surface thereof such taht when the body is partly in water and partly in liquid the portion of the layer in the water will change color to provide an indication or the level of water in the tank when the body is withdrawn from the tank, and second means for sensing a change in the level of water in the tank.
Claim 8
Dependent Claim
27 words
the leak detector of claim 4 wherein said body is a cylindrical casing of said leak detector and said sensing means is mounted in said cylindrical casing.
Claim 9
Dependent Claim
29 words
The leak detector of claim 5 wherein said sensing means comprises a sensor assembly including an array of sensor arranged along a line at an angle to the horizontal.
Claim 10
Dependent Claim
69 words
The leak detector of claim 6 wherein each of said sensors is a conductive element and said sensing means further comprises an electrical circuit for each sensor including a voltage source, one of said conductive elements, a ground (current-return) element positionable in contact with the liquid and the water and means for detecting a change in the conductivity of said circuit indicative of a change in the water level.
Claim 11
Dependent Claim
22 words
The leak detector of claim 7 wherein said sensing means includes means for placing said array of sensors across the water-liquid interface.
Claim 12
Dependent Claim
75 words
The leak detector for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank and second means for sensing a change in the level of water in the tank comprising a sensor assembly including an array of sensors arranged along a line at an angle to the horizontal.
Claim 13
Dependent Claim
75 words
The leak detector for determining a bottom leak in an above ground tank of liquid hydrocarbons having a lower specific gravity and a lower conductivity than water, said detector comprising first means for determining the level of water in said tank and second means for sensing a change in the level of water in the tank comprising a sensor assembly including an array of sensors arranged along a line at an angle to the horizontal.
Claim 14
Dependent Claim
42 words
The leak detector of claim 9 wherein each of said sensor is a conductivity element and said sensing means includes an electrical circuit for each sensor, an A.C. conductivity meter and switch means for selectively coupling said electrical circuit with said meter.
Claim 15
Dependent Claim
68 words
The leak detector of claim 9 wherein each of said sensors is a conductive element and said sensing means further comprises an electrical circuit for each sensor including a voltage source, one of said conductive elements, a ground (current-return) element positionable in contact with the liquid and the water and means for detecting a change in the conductivity of said circuit indicative of a change in water level.
Claim 16
Dependent Claim
58 words
The leak detector of claim 11 wherein said means for detecting a change in the conductivity of said circuit includes a lamp circuit including a lamp and means for causing said lamp to be energized when said conductive element is in the water and to be intermittently energized (to blink) when said conductive element is in the liquid.
Claim 17
Dependent Claim
23 words
The leak detector of claim 9 wherein said sensor assembly incudes means for releasably placing said array of sensors across the water-liquid interface.
Claim 18
Dependent Claim
16 words
The leak detector of claim 9 including means for flushing or washing said array of sensors.
Claim 19
Dependent Claim
15 words
The leak detector of claim 9 wherein each of said sensors is a thermal sensor.
Claim 20
Dependent Claim
27 words
The leak detector of claim 9 including means for adjusting the angle of the line along which the array of sensors is positioned relative to the horizontal.
Claim 21
Dependent Claim
16 words
The leak detector of claim 9 including a casing in which said sensor assembly is mounted.
Claim 22
Dependent Claim
67 words
The leak detector of claim 17 wherein said casing has at least one vent hole in the top thereof and has in a side wall thereof adjacent a lower end thereof at least one opening through which fluid such as water or liquid in the tank can gain entry into the casing so as to come in contact with the array of sensors of said sensor assembly.
Claim 23
Dependent Claim
43 words
The leak detector of claim 18 including baffle means fixed to and extending about said casing side wall laterally outwardly of said at least one opening for preventing debris at the interface between the water and the liquid from entering into said casing.
Claim 24
Dependent Claim
42 words
The leak detector of claim 17 including coupling means at the top of said casing to which a cable can be attached for raising and lowering said leak detector into the tank and ballast means at the lower end of said casing.
References Cited (Backward Citations)
US4646560A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-12 | 1991-10-12 | 1992-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-12 | 1995-10-12 | 1996-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-12 | 1999-10-12 | 2000-04-12 | $7700.00 | Window Closed / Lapsed |