US3841146A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automated volume monitoring system
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1973-03-26
•
Granted: 1974-10-15
•
Expires: 1993-03-26
Abstract
Abstract A system for detecting leaks in buried storage tanks by measuring change in liquid level, comprising a product containing reservoir suspended from an electronic load cell for measuring any weight loss and thermal sensor for detecting any change in average product temperature. A volume calculating circuit combines the weight change and temperature change signals to produce a temperature corrected output which may be suitably displayed. Zero change in net volume is indicated if the product level changes due only to a rise or fall in temperature. However, if the product level changes due to a leak or ground water entering the tank an accurate measurement of the volume change is obtained.
Inventors
- 👤 N Cross
- 👤 J Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:04
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/26; G01M3/32; G01M3/3236; G01M3/3245
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
167 words
An automated volume monitoring system for a product storage tank comprising: a. a vertically adjustable tube for containing product at a predetermined test level and adapted to be disposed in the fill pipe of said storage tank; b. thermal sensor means for sensing the average temperature of said product; c. suction means operably disposed for contact with said product surface substantially at said predetermined test level within said tube; d. a reservoir for containing a predetermined amount of said product; e. level maintenance means connected to said suction means and said reservoir operable in response to a change in said predetermined test level so as to maintain said test level substantially constant; f. drain means connected between said reservoir and said tube for supplying product from said reservoir to said tube when said suction means loses contact with said product surface until said predetermined test level is obtained; and g. load cell means operably associated with said reservoir for measuring any weight change of the product therein.
Claim 2
Dependent Claim
167 words
An automated volume monitoring system for a product storage tank comprising: a. a vertically adjustable tube for containing product at a predetermined test level and adapted to be disposed in the fill pipe of said storage tank; b. thermal sensor means for sensing the average temperature of said product; c. suction means operably disposed for contact with said product surface substantially at said predetermined test level within said tube; d. a reservoir for containing a predetermined amount of said product; e. level maintenance means connected to said suction means and said reservoir operable in response to a change in said predetermined test level so as to maintain said test level substantially constant; f. drain means connected between said reservoir and said tube for supplying product from said reservoir to said tube when said suction means loses contact with said product surface until said predetermined test level is obtained; and g. load cell means operably associated with said reservoir for measuring any weight change of the product therein.
Claim 3
Dependent Claim
44 words
An automated volume monitoring system according to claim 1 including volume calculating means operably connected with said thermal sensor means and said load cell means for producing a temperature corrected output signal representative of any change in volume of said product in said reservoir.
Claim 4
Dependent Claim
46 words
An automated volume monitoring system according to claim 2 including recorder means connected to said volume calculating means for displaying said temperature corrected output signal whereby product-out leakage is indicated by a constant negative slope and ground water in-leakage is indicated by a constant positive slope.
Claim 5
Dependent Claim
62 words
An automated volume monitoring system according to claim 2 wherein said volume calCulating means comprises an electronic circuit including circuit means for providing signals corresponding to product temperature and weight change in said reservoir, and a summing circuit connected for combining said signals to provide said temperature corrected output signal so that changes in product volume due only to temperature are eliminated.
Claim 6
Dependent Claim
37 words
An automated volume monitoring system according to claim 1 including pump means for continuously circulating a sample flow of the product past said thermal sensor and minimizing thermal variations within the product contained in said storage tank.
Claim 7
Dependent Claim
37 words
An automated volume monitoring system according to claim 5 wherein said tube is coaxial with said fill pipe and said fill pipe includes separate annular peripheral inlet and outlet chambers in operable communication with said pump means.
Claim 8
Dependent Claim
51 words
An automated volume monitoring system according to claim 1 wherein said level maintenance means comprises a pump for maintaining said test level so that when said test level drops said pump transfers additional product to said tube and when said test level rises said pump transfers excess product to said reservoir.
Claim 9
Dependent Claim
59 words
A volume monitoring system for a product storage tank comprising: a. tube means for containing said product at a predetermined head height; b. reservoir means separate from said storage tank for containing a predetermined amount of said product; and c. means operably connected between said tube means and said reservoir means for maintaining said predetermined head height substantially constant.
Claim 10
Dependent Claim
59 words
A volume monitoring system for a product storage tank comprising: a. tube means for containing said product at a predetermined head height; b. reservoir means separate from said storage tank for containing a predetermined amount of said product; and c. means operably connected between said tube means and said reservoir means for maintaining said predetermined head height substantially constant.
Claim 11
Dependent Claim
24 words
A volume monitoring system according to claim 8 wherein said tube means is adjustable to permit variation in the head height of said product.
Claim 12
Independent Claim
150 words
A method for determining a change in volume of a product in a storage tank as a result of leakage comprising the steps of a. establishing in a tube within said storage tank a substantially constant test level of said product at a height above the tank casing; b. providing a reservoir of said product separate from said storage tank; c. obtaining uniform temperature of the product in said tank; d. transferring sufficient product between said tube and said reservoir in response to changes in said head height in order to maintain said predetermined head height substantially constant; e. weighing the change in volume of product in said reservoir which change corresponds to a volume change in product in said storage tank; and f. determining the amount of product volume change in said storage tank as a function of the product volume change in said reservoir due only to leakage.
Claim 13
Independent Claim
150 words
A method for determining a change in volume of a product in a storage tank as a result of leakage comprising the steps of a. establishing in a tube within said storage tank a substantially constant test level of said product at a height above the tank casing; b. providing a reservoir of said product separate from said storage tank; c. obtaining uniform temperature of the product in said tank; d. transferring sufficient product between said tube and said reservoir in response to changes in said head height in order to maintain said predetermined head height substantially constant; e. weighing the change in volume of product in said reservoir which change corresponds to a volume change in product in said storage tank; and f. determining the amount of product volume change in said storage tank as a function of the product volume change in said reservoir due only to leakage.
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) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |