Flatness-measuring roll having sensor bars extending in the strip-travel direction

A method of determining flatness defects of a strip using a flatness-measuring roll comprising:

• a roll body having a cylindrical outer surface and a central axis;
• a plurality of measuring bars axially spaced along the body, recessed in the body, having outer faces flush with the body surface, and each at least limitedly radially shiftable relative to the body, the bars being angularly elongated and each extending along a plane substantially perpendicular to the roll axis and each having of a constant width measure parallel to the roll axis over generally all of a respective total angular length;
• at least two respective force-measuring sensors braced radially between each of the bars and the roll body, the method comprising the steps of:
• passing the strip over the roll body in a strip-travel direction substantially perpendicular to a vertical plane including the axis such that the strip entrains and rotates the body, whereby the strip passes over the sensor bars and radially inwardly presses the sensor bars;
• detecting the radial inward pressure exerted on the sensor bars with the force-measuring sensors and thereby determining flatness defects in the strip across a strip width perpendicular to the travel direction.