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Electro Magnetic Acoustic Transducers
These Sonatest EMAT transducers consist of a Neodymium-Iron-Boron Magnet and a specially designed field coil. The permanent magnet produces a vertically polarised constant magnetic field that penetrates the outer surface of the material. The Flaw Detector generates an alternating current in the coil, which in turn produces an Eddy current field and a Lorentz Force in the material being tested. When used with ferromagnetic materials with oxidized coatings, the electromagnetic forces set up in the surface layer use the magnetostrictive principle to transmit and receive an ultrasonic pulse.
Electro Magnetic Acoustic Transducers Overview
- A non-contact shear wave EMAT. The construction is in plastic case with side cable entry and knurled grip, or in a rugged brass case with integral adjustable wear/ distance ring.
- Measures the thickness though oxidized and corroded surfaces
- Does not require any couplants (Oil, or Water)
- No surface grinding required and therefore no further damage to material under inspection.
- Accuracy of EMAT +/- 0.1mm (If used with Sonatest DFDs)
- Neodymium-Iron-Boron Magnet for ultra high field strength
- Boiler tubes with oxidised and corroded surfaces
- Incinerators and refuse burners
- Nickel or Permalloy plated ferrous metals
- Superheated tubes with scale up to 5-7 mm thick
- High temperature operation
Electro Magnetic Acoustic Transducers Specification