EP0333100A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method and apparatus for detecting defective portion on non-exposed outer surface of pipe
Assignee: JFE Engineering Corp
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Filing: 1989-03-13
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Granted: —
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Expires: 2009-03-13
Abstract
Abstract A method and apparatus for detecting a defective portion on the non-exposed outer surface of a pipe (19), which comprises: heating or cooling a pipe, the outer surface (19b) of which is not exposed, from the side of the inner surface (19a) thereof so that a difference in temperature is produced between a portion of the inner surface (19a) of the pipe corresponding to an accumulation (20a) of foreign matters or a thinner portion (20b) as a defective portion on the outer surface (19b) not exposed of the pipe and a portion of the inner surface (19a) of the pipe corresponding to a normal portion of the outer surface (19b) of the pipe; then shooting the inner surface of the pipe by means of a thermal imaging system (9) while the difference in temperature still remains on the inner surface (19a) of the pipe to obtain a thermal image of the difference in temperature; and detecting the accumulation (20a) of foreign matters or the thinner portion (20b) as the defective portion (20) on the outer surface (196) of the pipe by means of the thus obtained thermal image.
Inventors
- 👤 Toshio Koshihara
- 👤 Koji Ishihara
- 👤 Toru Hirashima
- 👤 Shunichiro Ishida
- 👤 Haruhito Okamoto
- 👤 Yuji Matoba
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 22:13
CPC Classifications
G; G01; G01N; G01N25/00; G01N25/72
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
144 words
A method for detecting a defective portion on the outer surface not exposed of a pipe, characterized by: heating or cooling a pipe from the side of the inner surface thereof so that a difference in temperature is produced between a portion of the inner surface of said pipe corresponding to a defective portion on the outer surface not exposed of said pipe and a portion of the inner surface of said pipe corresponding to a normal portion of the outer surface of said pipe; then shooting the inner surface of said pipe by means of a thermal imaging system while said difference in temperature still remains on the inner surface of said pipe to obtain a thermal image of said difference in temperature; and detecting said defective portion on the outer surface of said pipe by means of the thus obtained thermal image.
Claim 2
Independent Claim
144 words
A method for detecting a defective portion on the outer surface not exposed of a pipe, characterized by: heating or cooling a pipe from the side of the inner surface thereof so that a difference in temperature is produced between a portion of the inner surface of said pipe corresponding to a defective portion on the outer surface not exposed of said pipe and a portion of the inner surface of said pipe corresponding to a normal portion of the outer surface of said pipe; then shooting the inner surface of said pipe by means of a thermal imaging system while said difference in temperature still remains on the inner surface of said pipe to obtain a thermal image of said difference in temperature; and detecting said defective portion on the outer surface of said pipe by means of the thus obtained thermal image.
Claim 3
Dependent Claim
133 words
The method as claimed in Claim 1, characterized by: heating said pipe from the side of the inner surface thereof so that a difference in temperature is produced between a portion of the inner surface of said pipe corresponding to said defective portion on the outer surface of said pipe, on the one hand, and a portion of the inner surface of said pipe corresponding to said normal portion of the outer surface of said pipe, on the other hand; then obtaining said thermal image of said difference in temperature, which has a portion showing a lower temperature, corresponding to an accumulation of foreign matters as said defective portion on the outer surface of said pipe; and detecting said accumulation of foreign matters as said defective portion by means of said terminal image.
Claim 4
Dependent Claim
130 words
The method as claimed in Claim 1, characterized by: heating said pipe from the side of the inner surface thereof so that a difference in temperature is produced between a portion of the inner surface of said pipe corresponding to said defective portion on the outer surface of said pipe, on the one hand, and a portion of the inner surface of said pipe corresponding to said normal portion of the outer surface of said pipe, on the one hand; then ob taining said thermal image of said difference in temperature, which has a portion showing a higher temperature, corresponding to a thinner portion as said defective portion on the outer surface of said pipe; and detecting said thinner portion as said defective portion by means of said thermal image.
Claim 5
Dependent Claim
133 words
The method as claimed in Claim 1, characterized by: cooling said pipe from the side of the inner surface thereof so that a difference in temperature is produced between a portion of the inner surface of said pipe corresponding to said defective portion on the outer surface of said pipe, on the one hand, and a portion of the inner surface of said pipe corresponding to said normal portion of the outer surface of said pipe, on the other hand; then obtaining said thermal image of said difference in temperature, which has a portion showing a higher temperature, corresponding to an accumulation of foreign matters as said defective portion on the outer surface of said pipe; and detecting said accumulation of foreign matters as said defective portion by means of said thermal image.
Claim 6
Dependent Claim
129 words
The method as claimed in Claim 1, characterized by: cooling said pipe from the side of the inner surface thereof so that a difference in temperature is produced between a portion of the inner surface of said pipe corresponding to said defective portion on the outer surface of said pipe, on the one hand, and a portion of the inner surface of said pipe corresponding to said normal portion of the outer surface of said pipe, on the other hand; then obtaining said thermal image of said difference in temperature, which has a portion showing a lower temperature, corresponding to a thinner portion as said defective portion on the outer surface of said pipe; and detecting said thinner portion as said defective portion by means of said thermal image.
Claim 7
Independent Claim
114 words
An apparatus for detecting a defective portion on the outer surface not exposed of a pipe, characterized by comprising: a pig (2) travellable through a pipe, the outer surface of which is not exposed, in the axial direction of said pipe; at least one temperature change imparting means (6), mounted on said pig (2), for heating or cooling said pipe from the side of the inner surface thereof; and at least one thermal imaging system (9), mounted on said pig (2), for shooting the inner surface of said pipe heated or cooled by said at least one temperature change imparting means (6) to obtain a thermal image of the inner surface of said pipe.
Claim 8
Independent Claim
114 words
An apparatus for detecting a defective portion on the outer surface not exposed of a pipe, characterized by comprising: a pig (2) travellable through a pipe, the outer surface of which is not exposed, in the axial direction of said pipe; at least one temperature change imparting means (6), mounted on said pig (2), for heating or cooling said pipe from the side of the inner surface thereof; and at least one thermal imaging system (9), mounted on said pig (2), for shooting the inner surface of said pipe heated or cooled by said at least one temperature change imparting means (6) to obtain a thermal image of the inner surface of said pipe.
Claim 9
Dependent Claim
131 words
The apparatus as claimed in Claim 6, wherein: said at least one temperature change imparting means (6) comprises a plurality of temperature change imparting means, and said plurality of temperature change imparting means are arranged in the circumferential direction of said pipe at equal intervals; said at least one thermal imaging system (9) comprises a plurality of thermal imaging systems in a number equal to that of said plurality of temperature change imparting means (6), and said plurality of thermal imaging systems are arranged behind said plurality of temperature change imparting means (6) relative to the travelling direction of said pig (2); and each pair of said temperature change imparting means (6) and said thermal imaging system (9) are arranged on the same plane containing the center axis of said pipe.
Claim 10
Dependent Claim
43 words
The apparatus as claimed in Claim 6, wherein: said apparatus contains a driving mechanism (14) for rotating said at least one temperature change imparting means (6) and said at least one thermal imaging system (9) around the center axis of said pig (2).
Claim 11
Dependent Claim
64 words
The apparatus as claimed in Claim 6, wherein: at least one infrared ray shielding plate (10, 10′), for preventing infrared rays emitted from said at least one temperature change imparting means (6) from coming into said at least one thermal imaging system (9), is provided between said at least one temperature change imparting means (6) and said at least one thermal imaging system (9).
Claim 12
Independent Claim
36 words
The apparatus as claimed in any one of Claims 6 to 9, wherein: said apparatus includes a means (11) for storing said thermal image obtained by means of said at least one thermal imaging system (9).
Claim 13
Dependent Claim
22 words
The apparatus as claimed in Claim 10, wherein: said means (11) for storing said thermal image is mounted on said pig (2).
References Cited (Backward Citations)
No citation records indexed.
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