Machine Vision for Slab Gauge Inspection

The slab dimension systems are typically installed before the primary mill. At this location, the system can be used to check the slab size before the first pass.

Slabs need to be measured at several points in the process. Just before rolling it is vital to ensure that it is the right dimension slab that is ready for rolling. If it is the wrong size the result will be a plate rolled to wrong dimensions, or even worse it could wreck the mill stand.

The vision system camera is mounted 20 meters above the transfer table at the lighting walkway. When the slab passes under the optical center of the camera, a series of length and width measurements are calculated and averaged.
A 12 meter long slab will be measured with accuracy better than 12 mm.

The system is fully automatic and triggers when the slab is passing under the camera. The measurements are passed to the mill computer and to the mill operator.