A wooden stick isn’t the most precise metrology tool at the best of times. It’s also flammable. Nevertheless, it’s still widely used in hot rolling mills to perform spot checks of steel profiles heated to temperatures in excess of 1000°C.
A stick does not even have the advantage of being simple to deploy. The person taking the measurement has to apply just the right amount of pressure to quickly capture an imprint of the hot steel in the wood, draw the charred stick away from the hot surface at the correct time, cool it and gauge the results with a manual caliper. All while remaining safe.
Like other manufacturers, rolling mills depend on inline inspections to pinpoint sources of errors without holding up production. But until recently there were no portable and easy-to-use metrology systems capable of withstanding extreme heat while taking inline measurements of long steel products between rolling stands. So, the wooden stick prevailed.
Now a portable measuring tool from Hexagon’s NEXTSENSE has transformed the lives of a rolling mill’s quality inspection teams. With the Calipri RC220 they can capture measurements with 0.2mm of accuracy at any point on the roll line without having to come into contact with the hot steel object. And the Calipri RC220 displays and analyses profile data directly on the system’s tablet, making it easy to see whether the most important dimensions are in or out of tolerance and to compare the captured results with the desired shape.
Calipri RC220 also makes it easy to immediately verify the accurate set-up of the rolling stands after changing the product or trying out a new profile shape or size.
Watch our video to see how the Calipri RC220 is used at Marienhütte GmbH’s rolling mill in Graz.
