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TISEC delivers Practical Pattern Recognition Workshop for NDT in Montreal, Canada, June 28-30, 2010

TISEC's ASTIA™ Above-ground Storage Tank Inspection and Assessment goes live, March 2010.

Level III UT Training course completed in State College, PA, March 2010.

WINS presents talk on ultrasonic guided wave potential towards helicopter maintenance to Indian Air force, February 2010.

WINS funded by Transportation Research Board to develop Bridge Cable Inspection Technology, February 2010.

Watch video of Wireless Acoustic Emission Sensor Network for Bridge Structural Health Monitoring.

2010 NDT Training Course Schedule is available now!

New look of TISEC's Super ICEPak® web site, November 2009.

Download and try out TISEC's Super ICEPak® today, contact TISEC for a trial key, November 2009.

New Brunswick DOT has awarded TISEC to inspect LRUT bridge cables on 3 cable-stay bridges using new MsS system, November 2009.

WavesInSolids acquires state-of-the-art equipment for enhanced Guided Wave Inspection Services for Pipelines and Bridge Cables, November 2009.

WavesInSolids delivers Acoustic Emission Level III Training Course in Kuala Lumpur, Malaysia, October 5-9, 2009

WavesInSolids is awarded contract with U.S. Department of Energy for developing inspection technology for health monitoring of coal power plant components, August 2009

WavesInSolids presents a paper at NYC Bridge Conference titled "Structural health monitoring using wireless acoustic emission sensor network" in August, 2009

WavesInSolids is awarded contract with NSF for developing inspection technology for Steel Piles, July 2009

WavesInSolids presents "Acoustic emission input to inspection- based bridge maintenance" at theInternational Conference on Fracture & Fatigue in July, 2009

Transformer Inspection using Acoustic Emission

Acoustic emission (AE) is a nondestructive testing technology that may be used to detect and locate partial discharges (PD) in oil-immersed power transformers and reactors. The technology may be applied to factory and field transformers. AE testing is commonly used after PD has been detected by another diagnostic procedure such as dissolved gas analysis or electrical measurement.

AE testing may be used to detect and locate PD from:

  • The outside of the winding
  • Between the core and the tank,
  • Arcing/tracking of the oil surface
  • Arcing/tracking of the bushing surface in the oil
  • The de-energized tap changer
  • The on-load tap changer.

PD detection from within the winding, and in between the winding and core, is difficult due to acoustic emission attenuation.

WINS uses the guidelines set forth in IEEE Standard C57.127-2007 "Guide for the Detection and Location of Acoustic Emissions from Partial Discharges in Oil-Immersed Power Transformers and Reactors for all inspections".

Partial discharges in oil-immersed transformers emit acoustic energy that may be detected using sensors mounted on the tanks outside wall. Acoustic emission from partial discharges are analyzed according to their intensity or amplitude, rise time and counts. Intense partial discharges from the outside of the winding, for instance, emit high amplitude PDs. PDs from within the winding are generally low amplitude and difficult to detect.

Other parameters including load current, pump current, temperature, and load tap changer motor current may be acquired and correlated with AE data to identify the operating conditions that cause PD.