It is well known that refractory linings in steel mill ladles have limited lives, and useful life may be shortened even more due to breakage of refractory bricks from mechanical shock. As the lining wears or develops breaks, the outer part of a transport ladle can be exposed to molten metal. If not caught in time, the result can be ladle disintegration and a molten metal breakout, threatening the lives of workers and destroying equipment.

Usually the thermal imaging camera from FLIR is placed in robust housings, and located in fixed positions where they have a clear view of a filled ladle as it passes by on the gantry crane. Those cameras capture video images of the ladle in real time, and calculate temperatures over the ladle’s surface. A few cameras can cover the entire surface of the ladle, but typically a few regions of interest (ROIs) are predefined for closer scrutiny and analysis. The thermal images of ROIs where failures are more likely to occur can be stored in PC memory for later comparison to current images. Defining ROIs also allows ViperVision software to ignore high temperatures on objects around the ladle that are within the camera’s field of view (FOV), which in turn lowers the amount of unwanted alarms.

These thermal video images and corresponding temperature data are carried over Ethernet and fiber optic cables to the industrial PC, which avoids problems from the electrically noisy mill environment.