Posted on 19 Jun 2012
JFE Steel uses various diagnostic devices to assess the deterioration and remaining life of steel structures with the purpose of ensuring safe operation. As one such device, the authors developed a remote control weld crack detection device mounted on a self-running cart. Time of flight diffraction (TOFD) was adopted, as this method satisfies both improved accuracy and continuous measurement. Simultaneous measurement of vertical and lateral cracks on an high temperature (200°C) vertical surface is possible. Among other features, magnetic wheels capable of traveling over 3-dimensional curved surfaces at temperatures up to 200°C are used in the self-running cart. The device has already been applied to diagnosis of welding line cracks in commercial blast furnace hot stoves, and improved efficiency and enhanced work safety have been confirmed.
