US4190501A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for measuring internal metal stress
Assignee: Transworld Drilling Co
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Filing: 1978-08-21
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Granted: 1980-02-26
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Expires: 1998-08-21
Abstract
Abstract An apparatus and procedure for measuring internal metal stress and determining the effectiveness of metal stress-relief treatments. More specifically, an apparatus and procedure for determining the effectiveness of metal stress-relief by heat treatment in the heat-affected zone surrounding a metal weld. The apparatus comprises an electrical half-cell and a unique bridge system designed to provide intimate physical contact between the electrical half-cell and a metal surface. The apparatus permits a metal to half-cell electrical potential measurement to be made at various locations upon the metal surface. The electrical potential measurements provide a means of evaluating the efficiency of a stress-relief treatment in reducing internal stress within a metal.
Inventors
- 👤 Olen L. Riggs, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:53
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/4166
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
158 words
A process for measuring internal stress in metals by surface testing comprising: providing a metal surface; providing a half-cell assembly comprising a body having a passageway therethrough with a compressible mask having a passageway therethrough positionally disposed and mounted upon one end of the body surrounding the passageway therethrough and in communicating alignment therewith, a reference electrode half-cell with a wiping collar having a passageway therethrough positionally disposed and mounted about the reference electrode half-cell, the wiping collar being at least partially inserted within the open end of the passageway through the body opposite the end whereon the compressible mask is positioned, and a saturated electrolyte solution contained in the passageway within the body; positioning the passageway through the compressible mask of the half-cell assembly in juxtaposition with the metal surface; compressing the compressible mask against the metal surface by application of axial force; and measuring the electrical potential between the metal surface and the reference electrode half-cell.
Claim 2
Dependent Claim
158 words
A process for measuring internal stress in metals by surface testing comprising: providing a metal surface; providing a half-cell assembly comprising a body having a passageway therethrough with a compressible mask having a passageway therethrough positionally disposed and mounted upon one end of the body surrounding the passageway therethrough and in communicating alignment therewith, a reference electrode half-cell with a wiping collar having a passageway therethrough positionally disposed and mounted about the reference electrode half-cell, the wiping collar being at least partially inserted within the open end of the passageway through the body opposite the end whereon the compressible mask is positioned, and a saturated electrolyte solution contained in the passageway within the body; positioning the passageway through the compressible mask of the half-cell assembly in juxtaposition with the metal surface; compressing the compressible mask against the metal surface by application of axial force; and measuring the electrical potential between the metal surface and the reference electrode half-cell.
Claim 3
Dependent Claim
45 words
The process of claim 1 defined further to include the step of: applying axial force to the wiping collar within the half-cell assembly to compress the saturated electrolyte solution contained therein and cause the solution to be extruded through the passageway in the compressible mask.
Claim 4
Dependent Claim
111 words
The process of claim 1 defined further to include the steps of: removing the axial force causing compression of the compressible mask; applying axial force to the wiping collar within the half-cell to compress the saturated electrolyte solution contained therein and cause the solution to be extruded through the passageway in the compressible mask; removing the extruded electrolyte solution; repositioning the passageway through the compressible mask of the half-cell assembly in juxtaposition with a new portion of the metal surface; recompressing the compressible mask against the metal surface by application of axial force; and measuring the electrical potential between the new portion of the metal surface and the reference electrode half-cell.
Claim 5
Dependent Claim
26 words
The process of claim 1 in which the saturated electrolyte solution is defined further as including a gelling agent to thicken the solution into a gelatinate.
Claim 6
Dependent Claim
12 words
The process of claim 4 in which the gelling agent is agar.
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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) | 1983-02-25 | 1983-08-27 | 1984-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-25 | 1987-08-27 | 1988-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-25 | 1991-08-27 | 1992-02-26 | $7700.00 | Window Closed / Lapsed |