US3966871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for inspecting tubular cavities
Assignee: Kraftwerk Union AG
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Filing: 1974-11-19
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Granted: 1976-06-29
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Expires: 1994-11-19
Abstract
Abstract To inspect an internal zone of a tubular cavity having an open end, for example, a zone of possible damage in a heat-exchanger tube, an elastically hardenable casting plastic is transported to the zone and cast against the surface embraced by the internal zone, and after hardening to an elastic casting, is pulled from the zone for inspection outside of the open end of the cavity. Being elastic, the casting is not permanently deformed when pulled from the zone, the casting providing an undistorted physical image of the surface within the zone, permitting a determination of possible damage including pitting, cracks and the like.
Inventors
- 👤 Peter Schroder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:11
CPC Classifications
F; F17; F17D; F17D5/00; F17D5/02; B; B29; B29C; B29C39/00; B29C39/02; B29C39/026; B29C39/22; B29C39/24; G; G01; G01M; G01M3/00; G01M3/02; G01M3/26; G01M3/28; G01M3/2846; G21; G21C; G21C17/00; G21C17/002; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
206 words
A method for obtaining an image of the surface of an internal zone of a cavity having an open end, said method comprising transporting a flowable elastically hardenable casting plastic through said end to said zone and casting said plastic against said surface and hardening of said plastic to an elastic casting, pulling said casting from said zone and through said open end with said casting elastically retaining an image of said surface, dams for said cavity being first inserted through said end and initially moved to said zone, and with the dams flexibly interconnected against separation more than the extent of said zone, and said plastic being transported under pressure to said zone through a tube inserted through said end and the one of said dams most adjacent to said end, with said tube opening between said dams and said plastic being injected between said dams to separate the same so they embrace said zone, said dams being interconnected so as to hold the dams against said separation while said plastic is injected therebetween, and when pulling said casting from said zone, said casting elastically stretching and releasing itself from any depressions on the inside of said tube, said dams, while interconnected, permitting said stretching.
Claim 2
Independent Claim
206 words
A method for obtaining an image of the surface of an internal zone of a cavity having an open end, said method comprising transporting a flowable elastically hardenable casting plastic through said end to said zone and casting said plastic against said surface and hardening of said plastic to an elastic casting, pulling said casting from said zone and through said open end with said casting elastically retaining an image of said surface, dams for said cavity being first inserted through said end and initially moved to said zone, and with the dams flexibly interconnected against separation more than the extent of said zone, and said plastic being transported under pressure to said zone through a tube inserted through said end and the one of said dams most adjacent to said end, with said tube opening between said dams and said plastic being injected between said dams to separate the same so they embrace said zone, said dams being interconnected so as to hold the dams against said separation while said plastic is injected therebetween, and when pulling said casting from said zone, said casting elastically stretching and releasing itself from any depressions on the inside of said tube, said dams, while interconnected, permitting said stretching.
Claim 3
Dependent Claim
25 words
The method of claim 1 in which said dams are initially moved by being pneumatically blown through said cavity to said extreme of said zone.
Claim 4
Dependent Claim
26 words
The method of claim 2 in which said plastic is a low-consistency silicone elastomer which cures substantially at room temperatures to an elastically deformable hardened casting.
Claim 5
Dependent Claim
34 words
The method of claim 3 in which said dams are pulled by said tube from said zone and through said open end, to thereby pull said casting from said zone and through said end.
References Cited (Backward Citations)
US907724A
Cited
US2618014A
Cited
US2886852A
Cited
US3315017A
Cited
US3356777A
Cited
US3423500A
Cited
US3440314A
Cited
US3803276A
Cited
US3834422A
Cited
US3902528A
Cited
US3903730A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |