Method and apparatus for detecting defective portion on inner surface of pipe
US4872762A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 1988 |
| Grant date | Oct 10, 1989 |
| Priority date | — |
| Expiry date | Aug 2, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N25/72
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and an apparatus for detecting a defective portion on the inner surface of a pipe, the outer surface of which is exposed, includes: heating or cooling a pipe, the outer surface of which is exposed, from the side of the outer surface thereof so that a difference in temperature is produced between a portion of the outer surface of the pipe corresponding to an accumulation of foreign matters or a thinner portion as a defective portion on the inner surface thereof, and a portion of the outer surface of the pipe corresponding to a normal portion of the inner surface thereof; then shooting the outer surface of the pipe by means of a thermal imaging system while the above-mentioned difference in temperature still remains on the outer surface of the pipe to obtain a thermal image of the difference in temperature; and detecting the accumulation of foreign matters or the thinner portion as the defective portion of the inner surface of the pipe by means of the thus obtained thermal image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.