Measuring systems for plates

CROPTIMIZER® – PLATE PROFILE MEASUREMENT AND CUT OPTIMIZATION

THE REQUIREMENTS

The Ilsenburger Grobblech GmbH specializes in the rolling of small batches. The primary goal of the measurement system was to determine the optimum cut size of each raw plate, based on production requirements, so that the final product sizes could be cut from the raw plates with minimal amounts of scrap. 

These important measurements and calculations were required in order to optimize the production process. Flatness, in addition to the plate geometry, is a critical quality parameter. However, flatness was not currently being measured, other than a visual flatness check from the control pulpit. 

For these reasons the plant management decided to purchase a measurement system for plate profile, length and flatness. The proposed gauge location was immediately after the 9-roll hot leveler, but only very limited space was available. The maximum roller table speed at this location is 1 m/s (200 fpm) and the temperature of the plates ranges from 20 to 1,050 °C (70–1,922 °F).

 

The solution

The solution was to install an LAP laser gauge behind the exit of the hot leveler, which would measure the width, length and flatness of the plates. These values constitute the complete profile of the plates, including the shapes of the head and tail crop. Other shape anomalies like saber, necking and wedges would be captured as well.

THE MEASURING PRINCIPLES - LASER TRIANGULATION AND LASER DOPPLER

WIDTH: Two laser triangulation sensors mounted on each side of the roller table are used for measuring the width. To guarantee reliable measurements, especially for thin plates, these sensors are equipped with light band optics.

FLATNESS: The flatness gauge consists of 11 laser triangulation sensors mounted above the roller table in a straight line across the width of the plate. The sensors measure the precise distance to the plate surface and, when combined with the results of the length measurement, provide a complete flatness prof.

LENGTH: A Laser Doppler gauge is mounted above the roller table in the center of the table to measure the length of the plate as it is passes. Laser photocells with light band optics measure across the table to precisely detect the leading and trailing edges of the plates. A second, identical Laser Doppler gauge replaced the measuring wheel in front of the hot shears to assist with positioning during sectioning of the hot plates.

EXCELLENT BENEFITS FOR PRODUCTION

OPTIMAL FLATNESS

The results of the flatness measurement determine whether a plate takes the normal production process or needs to be re-leveled. Further more, the flatness measurement results are used to optimize the adjustment of the hot leveler.

 

YIELD CONTROL

The plate geometry measurements determine whether the desired finished plates can actually be obtained from the raw plates. The location of a subdivision cut, the length and position of a material sample, the crop shape, and the lengths of head and tail crops are computed and displayed for the operator. All results are used for further optimization of the slab size calculation.

 

IMPROVED PRODUCTION CONTROL

The measurement system is integrated in the material tracking system, providing immediate access to all plate geometry data and allowing inspection of production sequences to quickly diagnose and correct possible bottlenecks.

 

PRECISE SHEARING

The plate geometry and the location of the computed shearing lines are displayed for the operator of the hot leveler and the hot shears, allowing him to precisely position the plates under the hot shears in manual operation. In automatic mode, the measurement system provides control signals for the roller table to position the plates automatically under the hot shears.

 

COMPLETE DOCUMENTATION

The measurement system continuously archives the measurement data of all plates in a database, providing traceability of all sequences in the process chain.

 

Download Application report