The in-line Tread Crack Defect Detection system automatically detects cracks and defects in wheel treads by use of electromagnetic acoustic transduction (EMAT) technology. Two EMAT sensors in each rail induce signals into the wheel. The signals travel the circumference of the wheel and reflect off cracks and defects; a lack of reflected signals indicates no defects. A reflected signal is transmitted back to the central processor and analyzed to determine the extent of the defect. If warranted, notification for action is made immediately.

Key Features and Benefits:

  • Automatically detect internal flaws and damage. The Tread Crack Detection system literally looks inside the wheel, analyzing ultrasonic wave signals to “see” where a crack or defect is.
  • No couplant needed.IEM’s self-contained Electromagnetic Acoustic Transduction technology eliminates need for special couplant materials used by traditional ultrasonic inspection systems.
  • Operate in all temperatures. Because no couplant is needed, temperature and weather have no effect on IEM’s Tread Crack Detection system performance.
  • Practical application of IEM Patent. The underlying technology for the Tread Crack Detection System is derived in its entirety from IEM’s U.S. Patent 6,523,411 for a Wheel Inspection System.


IEM’s Tread Crack Detection system is based on an IEM patent and requires no liquid couplant, allowing it to operate in below freezing weather conditions. This system works best at low vehicle speeds and is, therefore, offered as a supplementary module for IEM’s Low Speed WISE system.