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EMAT
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Electromagnetic acoustic transducer (EMAT) is an ultrasonic nondestructive testing method where couplant is not needed since the sound is directly generated in the material underneath the transducer. Due to this couplant free feature, EMAT is particularly useful for the NDT applications of automated inspection. EMAT is an ideal transducer to generate Shear Horizontal (SH) bulk wave mode, Surface Wave, Lamb Wave and all sorts of other guided wave modes in metallic and/or ferromagnetic materials. As an emerging UT technique, EMAT can be used for both flaw detection as well as thickness measurement.
We offer thickness mapping services of boiler tubes using temate® TG-IS(B).
The temate® TG-IS(B) is designed for detecting and measuring wall loss, hydrogen damage and caustic gauging in boiler tubes.
Our EMAT boiler tube assessments will be done by partnership with Innerspec technologies, USA. Our technician partially trained by Innerspec technologies.
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The Innerspec company located in Lynchburg VA with offices in Europe and China, and representatives and distributors throughout the world. First EMAT (NASA) in 1989. First commercial EMAT in 1994. World leader in High-Power Ultrasound and EMAT with over 200 integrated. Systems installed in 25 countries, and the most complete line of standard equipment
Comparison of the most common inspection alternatives for corrosion measurement
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Technique
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Effectiveness
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Conclusion
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Wall-Loss Measurement
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Crack Detection
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Piezoelectric UT (normal beam)
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· Non-parallel walls and OD and ID pitting cause loss of signal. Not adequate with heavy OD or ID erosion
· Scale prevents transmission of signal
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· Back-wall attenuation technique permits quantification of problem once detected with other methods
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· Only practical for spot checking after thorough surface preparation.
· Not adequate when ID pitting is present
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EMAT UT (normal beam)
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· Non-parallel walls and OD and ID pitting cause loss of signal. Not adequate with heavy OD or ID erosion
· Capable of inspection on tubes with adhered scale with minimum surface preparation
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· Back-wall attenuation technique permits quantification once detected with other methods
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· Only practical for spot checking.
· Requires minimum surface preparation
· Not adequate when ID pitting is present
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Technique
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Effectiveness
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Conclusion
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Wall-Loss Measurement
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Crack Detection
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LFET/RFET
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· Detects pitting but does not provide wall-loss measurements
· Capable of inspecting tubes with adhered scale with minimum surface preparation
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· Detects cracks. Quantification performed with other methods
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· Provides scan of tube and detects most common defects
· No differentiation between cracks and pitting
· Lack of thickness measurement can lead to false calls
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Temate® TG-IS(C)
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- Provides accurate wall measurements even in the presence of ID and OD pitting
- Capable of inspecting tubes with adhered scale with minimum surface preparation
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- Detects cracks. Quantification performed with other methods
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- Provides scan of tube
- Measures wall loss accurately in any condition
- Detects cracks separately from wall loss problems for proper diagnosis
- Works on carbon steel and clad tubes
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The advantages of EMAT for pulse-echo flaw detection and thickness guaging, without the large capital outlay of replacing existing piezoelectric based flaw inspection systems and thickness/corrosion monitors. No couplant is needed. Thus the reliability of the scanning process is enhanced. The component's surface does not require preparation. It can be applied when the surface temperature is too high for a contact probe. Relatively fast and easily deployed.
Innerspec Technologies Products & Services:
· Integrated systems for inspection of welds, tubes, rolls, rods, billets, strip and plates and many other application specific solutions
· High-Power ultrasonic instrumentation
· Standard EMAT & Specialty Piezoelectric Sensors and Accessories
· Specialized In-Service solutions
· Research & Development
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