All inspection systems have advantages and disadvantages when compared to each other. The most important advantage of the Therm-O-Matic® is the linear relation between defect signal Δt and defect depth. Detailed research and test works enabled us to establish the effect by factors influencing the amplitude of the defect signal Δt and find technical solution to set, measure and adjust these parameters. The defect signal Δt is kept independent of speed, product dimension, product shape, coil size and surface temperature by continuous control of the process as the product goes through the installation.
This inspection principle/method was invented by Elkem Technology. The technology required to make this work was at that time not available on the civilian market. In cooperation with a company with good knowledge of military IR technology and real time signal processing technology Elkem developed an IR line scanner, signal processor, analyzing software and detection algorithms. A one-sided prototype was built and used to explore the possibilities and limitations of this new inspection method.