Flatness Measurement of Hot Strip by Laser Scanning Method

Development of a Shape Meter Employing the LED Dot Pattern Projection Method for a Hot Strip Finishing Mill

“…These are automatic flatness control (AFC) that controls the work roll bender and setup function that sets the initial conditions such as shift position of the work roll and load distribution of rolling stands by learning control. 6,7) As to a conventional flatness measurement method for a hot-rolled strip, the laser twin-beam method [8][9][10] and the multiple line pattern projection method 11,12) are well known. As to the laser twin-beam method, two laser rangefinders are installed at a distance in the rolling direction and measure the inclination angles of the strip from moment to moment, and the surface length and elongation rate of the strip are calculated by line integration of these.…”

“…(8), the strip surface inclination angle dy/dx can be expressed by Eq. (9). Then, the difference between maximum inclination angle and the minimum one is proportional to the steepness as expressed by Eq.…”