US5400646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid containment monitoring system
Assignee: MEPCO Inc
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Filing: 1993-11-04
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Granted: 1995-03-28
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Expires: 2013-11-04
Abstract
Abstract An electronic monitoring system to accurately measure a vacuum in an interstice between inner and outer walls of a dual-wall container or pipe which allows highly accurate analysis of vacuum differential to discover and confirm a leak in either the inner or outer walls of the container or pipe within minutes.
Inventors
- 👤 Donald A. Kraus
- 👤 Leale E. Streebin
- 👤 John E. Fagan
- 👤 Anthony W. Howl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:46
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/26; G01M3/32; G01M3/28; G01M3/2807; G01M3/283; G01M3/3236; G01M3/3263
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
183 words
A fluid containment and monitoring system comprising: a product tank having an inner wall, an outer wall and an interstice defined between the inner wall and the outer wall thereof; a reference tank having a reference volume therein; a pneumatic line connecting said reference tank with the interstice of said product tank, wherein the interstice, the reference volume and said pneumatic line define a system volume; a tank valve installed in said pneumatic line; a vacuum source connected to said reference tank for establishing a predetermined negative system pressure in the system volume when the tank valve is open; differential transducer means, connected to said pneumatic line, for providing a differential pressure reading between two points in said pneumatic line on opposite sides of said tank valve; and processor means, operatively connected to said differential transducer means, for obtaining the differential pressure reading from said transducer means at predetermined time intervals when the tank valve is closed and for analyzing changes in the differential pressure reading over time to detect fluid leakage in the inner wall or outer wall of said product tank.
Claim 2
Dependent Claim
183 words
A fluid containment and monitoring system comprising: a product tank having an inner wall, an outer wall and an interstice defined between the inner wall and the outer wall thereof; a reference tank having a reference volume therein; a pneumatic line connecting said reference tank with the interstice of said product tank, wherein the interstice, the reference volume and said pneumatic line define a system volume; a tank valve installed in said pneumatic line; a vacuum source connected to said reference tank for establishing a predetermined negative system pressure in the system volume when the tank valve is open; differential transducer means, connected to said pneumatic line, for providing a differential pressure reading between two points in said pneumatic line on opposite sides of said tank valve; and processor means, operatively connected to said differential transducer means, for obtaining the differential pressure reading from said transducer means at predetermined time intervals when the tank valve is closed and for analyzing changes in the differential pressure reading over time to detect fluid leakage in the inner wall or outer wall of said product tank.
Claim 3
Dependent Claim
21 words
The fluid containment and monitoring system of claim 1 wherein the inner wall of said product tank is a flexible bladder.
Claim 4
Dependent Claim
24 words
The fluid containment and monitoring system of claim 1 further comprising: absolute transducer means for providing an absolute pressure reading of said reference tank.
Claim 5
Dependent Claim
54 words
The fluid containment and monitoring system of claim 3 further comprising: processor means, operatively connected to said absolute transducer means, for obtaining the absolute pressure reading from said absolute transducer means at predetermined time intervals and for analyzing changes in the absolute pressure reading over time to detect fluid leakage in the system volume.
Claim 6
Dependent Claim
76 words
The fluid containment and monitoring system of claim 3 further comprising: processor means, operatively connected to said absolute transducer means, for obtaining the absolute pressure reading from said absolute transducer means at predetermined time intervals and for determining when the absolute pressure reading has risen from a predetermined first negative pressure to a predetermined second negative pressure; and means for evacuating said reference tank and the interstice of said product tank to the first negative pressure.
Claim 7
Dependent Claim
41 words
The fluid containment and monitoring system of claim 5 further comprising: processor means for counting the number of times said reference tank and the interstice of said product tank are evacuated to the first negative pressure in a predetermined time period.
Claim 8
Dependent Claim
49 words
The fluid containment and monitoring system of claim 6 further comprising: processor means for activating an alarm when the number of times said reference tank and the interstice of said product tank are evacuated to the first negative pressure in the predetermined time period exceeds a preset maximum therefor.
Claim 9
Dependent Claim
43 words
The fluid containment and monitoring system of claim 1 further comprising: a sump plate disposed in a lowermost area of the interstice of said product tank, said sump plate being arcuate to define a condensate sump in the interstice of said product tank.
Claim 10
Dependent Claim
30 words
The fluid containment and monitoring system of claim 8 further comprising: means, connected to said sump plate, for drawing liquid from the condensate sump and out of said product tank.
Claim 11
Dependent Claim
24 words
The fluid containment and monitoring system of claim 8 further comprising: a liquid detection sensor disposed in the condensate sump of said product tank.
Claim 12
Dependent Claim
39 words
The fluid containment and monitoring system of claim 10 further comprising: processor means, operatively connected to said liquid detection sensor, for activating an alarm in response to detection of liquid in the condensate sump by said liquid detection sensor.
Claim 13
Independent Claim
120 words
A method of monitoring a fluid containment for fluid leakage, the steps of the method comprising: providing a double-walled containment having inner walls and outer walls defining a substantially air-tight interstice therebetween, the inner walls defining a product chamber for containing fluid product; providing a reference tank having a reference volume therein; placing the reference volume in communication with the interstice of the containment; establishing a predetermined negative pressure within the reference volume and the interstice; isolating the reference volume from the interstice; measuring a differential pressure between the reference volume and the interstice at predetermined time intervals; analyzing the differential pressure at the predetermined time intervals to detect fluid leakage in the inner or outer walls of the containment.
Claim 14
Independent Claim
120 words
A method of monitoring a fluid containment for fluid leakage, the steps of the method comprising: providing a double-walled containment having inner walls and outer walls defining a substantially air-tight interstice therebetween, the inner walls defining a product chamber for containing fluid product; providing a reference tank having a reference volume therein; placing the reference volume in communication with the interstice of the containment; establishing a predetermined negative pressure within the reference volume and the interstice; isolating the reference volume from the interstice; measuring a differential pressure between the reference volume and the interstice at predetermined time intervals; analyzing the differential pressure at the predetermined time intervals to detect fluid leakage in the inner or outer walls of the containment.
Claim 15
Dependent Claim
44 words
The method of claim 12 further comprising the steps of: measuring the absolute pressure of the reference volume at predetermined time intervals; and analyzing change in absolute pressure of the reference volume over the predetermined time intervals to detect leakage in the reference volume.
Claim 16
Dependent Claim
63 words
The method of claim 12 further comprising the steps of: setting an upper limit of negative pressure for the reference volume; measuring the absolute pressure of the reference volume at predetermined time intervals; and venting the reference volume and interstice to the atmosphere when the absolute pressure of the reference volume is above the upper limit of negative pressure for the reference volume.
Claim 17
Dependent Claim
73 words
The method of claim 12 further comprising the steps of: setting a first negative pressure and a second negative pressure for the reference volume, the first negative pressure being more negative than the second negative pressure; measuring the absolute pressure of the reference volume at predetermined time intervals; and evacuating the reference volume and interstice to the first negative pressure when the absolute pressure of the reference volume reaches the second negative pressure.
Claim 18
Dependent Claim
68 words
The method of claim 15 further comprising the steps of: counting the number of times the evacuating step is performed within a predetermined time interval; setting a maximum number of times the evacuating step should be performed in the predetermined time interval when there is no fluid leakage; and activating an alarm when the number of times the evacuating step is performed exceeds the maximum number set therefor.
Claim 19
Dependent Claim
34 words
The method of claim 12 further comprising the steps of: providing a sump in a lowermost portion of the interstice of the containment; and detecting whether or not liquid is present in the sump.
Claim 20
Dependent Claim
79 words
The method of claim 17 further comprising the steps of: providing a liquid trap fluidly communicating with the sump and the reference volume; evacuating the reference volume and sump to a predetermined liquid purge negative pressure to draw liquid from the sump into the liquid trap when the presence of liquid is detected in the sump; and venting the reference volume and sump to the atmosphere until the absolute pressure of the reference volume reaches a predetermined negative pressure.
Claim 21
Dependent Claim
55 words
The method of claim 18 further comprising: setting a maximum number of iterations for performing the evacuating and venting steps; and performing the evacuating and venting steps of claim 18 until liquid is no longer detected in the sump or until the maximum number of iterations for performing the evacuating and venting steps is reached.
Claim 22
Dependent Claim
25 words
The method of claim 19 further comprising: activating an alarm when the maximum number of iterations for performing the evacuating and venting steps is reached.
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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) | 1998-03-27 | 1998-09-26 | 1999-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-27 | 2002-09-26 | 2003-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-27 | 2006-09-26 | 2007-03-28 | $7700.00 | Window Closed / Lapsed |