Inspection apparatus for electromagnetically detecting flaws in the wall of a pipe
US4510447A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 26, 1981 |
| Grant date | Apr 9, 1985 |
| Priority date | — |
| Expiry date | Oct 26, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/902
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus for detecting flaws in the wall of a ferromagnetic pipe is disclosed. The apparatus comprises an electromagnetic having poles in slideable contact with the surface of the wall of the ferromagnetic pipe to form a closed magnetic circuit and means for electrically connecting the coil of the electromagnetic to an input source of alternating current whereby a fluctuating magnetic field is induced generally axially through the wall of the pipe between the poles of the electromagnetic. The apparatus also comprises means adjacent the surface of the wall of the pipe between the poles of the electromagnet for sensing a leakage of the axial magnetic field therefrom and generating a signal corresponding to a sensed portion of the leakage. The apparatus further comprises means for electrically connecting the sensing means to a readable output device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.