Patent US3913378A successfully refreshed from Google Patents.
US3913378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for measuring fouling on metal surfaces
Assignee: Universal Oil Products Co
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Filing: 1974-04-08
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Granted: 1975-10-21
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Expires: 1994-04-08
Abstract
Abstract The measurement of material buildup, or fouling, on a metal surface from a liquid flow is provided by effecting a temperature differential measurement of heat conductivity through a heated conductive metal piece that is mounted to have one surface exposed to the liquid flow, while having the remaining portion thermally insulated from surrounding conditions, and then dividing such measurement with a temperature differential measurement for the liquid receiving convected heat across the zone of the interface between the surface of the metal piece and the flowing liquid. A preferred system provides for positioning thermocouple means to give a voltage signal of the temperature differential reading through the depth of the metal piece and another voltage signal indication of the temperature differential across the interface between the metal and the liquid and then feeding such signals into a voltage divider means to effect a voltage ratio reading that is indicative of material buildup on the metal surface.
Inventors
- 👤 Rudolf H Hausler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:46
CPC Classifications
G; G01; G01N; G01N25/00; G01N25/18; G01B; G01B7/00; G01B7/02; G01B7/06; G01K; G01K17/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
357 words
Apparatus for measuring the fouling of a metal surface exposed to the flow of a liquid stream by providing for means detecting an electrical signal responsive to the heat transfer taking place from a heated metal piece into a liquid stream passing over one face thereof and for dividing such signal into an electrical signal indicative of the differential temperature through the thickness of the metal piece, which compriSes in combination: a. means for mounting said metal piece to insulate it from ambient conditions while having one surface exposed to said stream; b. means for providing a constant heat input into said metal piece; c. means for measuring the temperature differential across the depth of said piece and providing an electrical output representative thereof; d. means for measuring variations in temperature for the convected heat across the interface between the liquid and the exposed surface of said metal piece and for generating an electrical output therefrom indicative of the temperature being measured; e. electrical divider circuit means for receiving the measurements of (c) and (d) and for reading out a resultant electrical signal indicative of changes in the ratio between the metal piece temperature differential and the temperature differential across the interface between the metal piece and the liquid flow to, in turn, provide a measurement of the fouling of the exposed metal surface; f. spaced apart thermocouples, positioned to obtain temperature effects from the opposing faces of said metal piece, having leads to similar metal portions of said thermocouples interconnected to thereby provide for a voltage output signal indicative of temperature differential across the depth of said piece; and g. an additional thermocouple means positioned to have a juncture in the liquid stream spaced from the exposed surface of said metal piece to receive convective heat from said surface, there being an interconnection of a lead from the metal forming the thermocouple juncture which is similar to said interconnected similar metal portions of said thermocouple junctures providing the differential temperature through said metal piece, whereby to further provide a voltage signal in turn representative of the convected temperature from said exposed surface of said metal piece.
Claim 2
Dependent Claim
357 words
Apparatus for measuring the fouling of a metal surface exposed to the flow of a liquid stream by providing for means detecting an electrical signal responsive to the heat transfer taking place from a heated metal piece into a liquid stream passing over one face thereof and for dividing such signal into an electrical signal indicative of the differential temperature through the thickness of the metal piece, which compriSes in combination: a. means for mounting said metal piece to insulate it from ambient conditions while having one surface exposed to said stream; b. means for providing a constant heat input into said metal piece; c. means for measuring the temperature differential across the depth of said piece and providing an electrical output representative thereof; d. means for measuring variations in temperature for the convected heat across the interface between the liquid and the exposed surface of said metal piece and for generating an electrical output therefrom indicative of the temperature being measured; e. electrical divider circuit means for receiving the measurements of (c) and (d) and for reading out a resultant electrical signal indicative of changes in the ratio between the metal piece temperature differential and the temperature differential across the interface between the metal piece and the liquid flow to, in turn, provide a measurement of the fouling of the exposed metal surface; f. spaced apart thermocouples, positioned to obtain temperature effects from the opposing faces of said metal piece, having leads to similar metal portions of said thermocouples interconnected to thereby provide for a voltage output signal indicative of temperature differential across the depth of said piece; and g. an additional thermocouple means positioned to have a juncture in the liquid stream spaced from the exposed surface of said metal piece to receive convective heat from said surface, there being an interconnection of a lead from the metal forming the thermocouple juncture which is similar to said interconnected similar metal portions of said thermocouple junctures providing the differential temperature through said metal piece, whereby to further provide a voltage signal in turn representative of the convected temperature from said exposed surface of said metal piece.
Claim 3
Dependent Claim
37 words
The apparatus of claim 1 further characterized in that a constant voltage input to an electrical resistance coil in contact with said metal piece provides the means for providing a constant heat input into said metal piece.
Claim 4
Dependent Claim
109 words
The apparatus of claim 1 still further characterized in that the voltage signal from the differential temperature through the metal piece is provided as one input into the electrical divider circuit means, and the voltage signal from the thermocouple positioned in the fluid stream which provides a voltage signal responsive to convective heat from the surface of the metal piece to the liquid is connected to said divider circuit means as a second input signal and a resulting varying voltage output from the divider circuit means is made connective to voltage reading means to thereby provide a measure of fouling of the exposed metal surface of said metal piece.
Claim 5
Dependent Claim
27 words
The apparatus of claim 3 still further characterized in that said voltage reading means is calibrated to give a direct measure of fouling on said metal piece.
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) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |