5. Magnetic leakage flux processes
5.1 Principle and physical basis
The theory of magnetic circuits indicates that the presence of an air gap corresponds to a strong local increase in the circuit's reluctance and therefore in the magnetic potential difference (m.p.d.), thus constituting an obstacle to magnetic flux, whose lines of force must then spread out laterally according to a leakage flux, as shown in figure 10 . This dispersion of flux lines occurs even with a very small air gap, as the reluctance ratio between air gap and circuit is inversely proportional to the relative permeability of the latter, i.e. a ratio of 500 to 1,000 for a ferromagnetic steel circuit excited below saturation.
This effect...
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Magnetic leakage flux processes
Eddy currents
Bibliography
References
Optics
Thesis
- - http://www.sudoc.abes.fr
- LIEBEAUX (N.) - Contribution à la modélisation de capteurs electromagnétiques : Application au contrôle non destructif par courants de Foucault. - Université de Paris-Sud (2002)....
Standardization
French standards
Association française de normalisation AFNOR http://www.boutique.afnor.fr
Non-destructive testing. Recueil AFNOR 2003.
- Essais non destructifs - Qualification et certification du personnel END - Principes généraux. - NF EN 473 - 12.00
Penetrant testing
- Essais non destructifs - Examen par ressuage - Partie 1 : principes généraux. (A09-120) - NF EN 571-1...
Organizations
COFREND Confédération française pour les essais non destructifs. - http://www.cofrend.com
The American Society of non-destructive techniques. - http://www.asnt.org
Radiation protection regulations
Decree 2003-296 of March 31, 2003 on the protection of workers against the dangers of ionizing radiation.
Decree 2002-460 of April 4, 2002 on the general protection of people against the dangers of ionizing radiation.
Decree 2001-215 of March 8, 2001 amending Decree 66-450 of June 20, 1966 on the general principles of protection against ionizing radiation....
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