Method and device for magnetic and ultrasonic testing of ferro-magnetic objects
US4727321A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 2, 1986 |
| Grant date | Feb 23, 1988 |
| Priority date | — |
| Expiry date | May 2, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/0422
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The subject of the invention is a method and a device for non-destructive testing of ferromagnetic bodies (1) for structural faults. The bodies (1) are magnetized. Structural faults cause changes in the magnetic field pattern which are measured with magnetic field detectors (6). Surface waves are generated electro-dynamically utilizing the magnetic field generated for magnetizing the body (1). Those structural faults extending up to the surface can be detected with the surface waves. To distinguish between the structural faults extending to the surface of the body at one point and those structural faults inside the body (1), it is determined whether the measured values gained both from the leakage flux and from the surface waves indicate structural faults or whether only the measured values gained from the leakage flux indicate structural faults.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.