Measurement of the transverse sheet thickness profile
The requirements expressed by cold rolled sheet users are increasingly strict, particularly with regard to the transverse thickness profile. An on-line measurement after cold rolling becomes necessary, fast enough to allow feedback to the rolling line and with good width resolution to obtain an accurate description of edge drops. A new generation of X-ray detectors designed to measure simultaneously up to a thousand points, with improved transverse resolution and an accuracy equal to existing devices, seems to answer the problem. The apparatus gives a measurement of a 140 mm long profile with a transverse resolution of 1 mm. For a measuring time lower than 1s, the accuracy is better than one percent, which is comparable to existing gauges. For the thicknesses corresponding to cold rolled sheets, the perturbations near the edge are not very important. The measurement is exact up to 3 mm from the edge, without special care. With a detector adapted to higher energy radiations, it would be possible to extend the method to thicker products, especially hot rolled sheets. The effects of diffused radiation would then become more important; the use of a mobile mask tested on the prototype would become necessary, whether or not combined with a calculated correction.
Bibliographic Reference: EUR 13112 FR (1990) 63 pp., FS, ECU 7.50
ISBN: ISBN 92-826-1946-X
Record Number: 199110074 / Last updated on: 1994-12-02
Original language: fr
Available languages: fr