US-12623268-B2 - Measuring the flatness of rolling trains for aluminium

US12623268B2US 12623268 B2US12623268 B2US 12623268B2US-12623268-B2

Abstract

A rolling stand for rolling a hot aluminium strip, having at the outlet side, in this order, a trimming device that cuts the metal strip from both sides such that only the remaining central region of the metal strip is fed to the downstream devices; a front deflection roller that deflects the metal strip away from a direct connecting line between the rolling stand and the rear deflection roller; a measuring assembly that has a mechanical excitation device that excites the metal strip to mechanically oscillate in the direction of its thickness and a measuring device that senses, for a plurality of regions of the metal strip lying adjacent to one another in the direction of the width of the metal strip, the amplitude of the excited mechanical oscillation of the respective region; and a coiling device that has a rear deflection roller upstream of a coiler.

Inventors

Jose Claudio BLANCO DE SOUZA

Assignees

PRIMETALS TECHNOLOGIES GERMANY GMBH

Dates

Publication Date: 20260512
Application Date: 20220124
Priority Date: 20210125

Claims (13)

1 . A rolling device for a metal strip from aluminum, wherein the rolling device has a roll stand with an outlet side; wherein the rolling device has a coiling device disposed on the outlet side of the roll stand, having a coiler and a rear deflection roller; wherein the rear deflection roller is disposed between the roll stand and the coiler; wherein the rolling device has a measuring assembly which is disposed between the roll stand and the rear deflection roller and is specified to determine a flatness of the metal strip; wherein the measuring assembly has a mechanical excitation device by means of which the metal strip in a thickness direction thereof is excitable to mechanically oscillate; wherein the measuring assembly has a measuring device by means of which, for a plurality of regions of the metal strip that lie next to one another in a width direction of the metal strip, an amplitude of an excited mechanical oscillation of a respective region of the metal strip is detectable, wherein the rolling device has a trimming device which is disposed on the outlet side of the roll stand and by means of which one band of the metal strip is severed on both sides of the metal strip so that only a remaining central region of the metal strip is supplied to the rear deflection roller and from the rear deflection roller to the coiler, and wherein the rolling device has a front deflection roller which is disposed between the trimming device and the measuring assembly and by means of which the metal strip is deflected from a direct connecting line between the roll stand and the rear deflection roller.
2 . The rolling device as claimed in claim 1 , wherein the mechanical excitation device is configured as a suction device by means of which the metal strip is periodically impinged with a vacuum.
3 . The rolling device as claimed in claim 1 , wherein the measuring device is configured as a measuring device operating in a contactless manner, by means of which the amplitude of the excited mechanical oscillation of the respective region of the metal strip is detectable in the contactless manner.
4 . The rolling device as claimed in claim 3 , wherein the measuring device for inducing eddy currents in the metal strip has a number of electromagnetic excitation devices, and for detection of the amplitude of the mechanical oscillation of each respective region has a respective electromagnetic receiver device by means of which an intensity of the eddy current excited in the respective region is detectable.
5 . The rolling device as claimed in claim 1 , wherein the front deflection roller in the thickness direction of the metal strip is movable substantially orthogonally to a direct connecting line of the roll stand and the rear deflection roller.
6 . The rolling device as claimed in claim 1 , wherein the front deflection roller is actuatable onto the metal strip from above.
7 . The rolling device as claimed in claim 1 , wherein the front deflection roller is mechanically connected to the measuring assembly such that the front deflection roller and the measuring assembly are movable only conjointly, and in that the front deflection roller and the measuring assembly are located on a same side of the metal strip.
8 . The rolling device as claimed in claim 7 , wherein the front deflection roller by way of a pivotably mounted lever arm is connected to the measuring assembly so that when the front deflection roller is actuated onto the metal strip a spacing of the measuring assembly from the metal strip remains constant when pivoting the lever arm.
9 . The rolling device as claimed in claim 8 , wherein the central deflection roller is mechanically connected to the measuring assembly such that the central deflection roller and the measuring assembly are movable only conjointly.
10 . The rolling device as claimed in claim 1 , wherein a central deflection roller is disposed between the measuring assembly and the rear deflection roller.
11 . The rolling device as claimed in claim 1 , wherein the measuring device is water-cooled.
12 . The rolling device as claimed in claim 1 , wherein a spacing of the measuring device from the metal strip is adjustable between a minimum spacing and a maximum spacing.
13 . The rolling device as claimed in claim 1 , wherein the metal strip is a hot metal strip, and wherein water cooling of the measuring device, minimum spacing of the measuring device from the hot metal strip, and maximum spacing of the measuring device of the hot metal strip are mutually adapted in such a manner that the measuring device at the minimum spacing is operated permanently with the water cooling, and at the maximum spacing is operated permanently without the water cooling or at least the measuring device is not damaged by heat received from the hot metal strip.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a 35 U.S.C. §§ 371 national stage application of International Application No. PCT/EP2022/051485, filed Jan. 24, 2022, which claims priority to European Patent Application No. 21153138.9, filed Jan. 25, 2021, the contents of which are incorporated herein by reference. FIELD OF THE INVENTION The present invention proceeds from a rolling device for a metal strip of aluminum wherein the rolling device has a roll stand,wherein the rolling device has a coiling device disposed on the outlet side of the roll stand, having a coiler and a rear deflection roller,wherein the rear deflection roller is disposed between the roll stand and the coiler,wherein the rolling device has a measuring assembly which is disposed between the roll stand and the rear deflection roller and is specified to determine a flatness of the metal strip,wherein the measuring assembly has a mechanical excitation device by means of which the metal strip in the thickness direction thereof is excitable to mechanically oscillate,wherein the measuring assembly has a measuring device by means of which, for a plurality of regions of the metal strip that lie next to one another in the width direction of the metal strip, the amplitude of the excited mechanical oscillation of the respective region of the metal strip is detectable. PRIOR ART Such a rolling device is known for rolling trains for cold-rolling steel. Purely by way of example, reference may be made to WO 98/38482 A1. The flatness of the metal strip can be determined from the detected amplitudes of the mechanical oscillations of the regions of the metal strip. This is also explained in more detail in the WO publication mentioned. SUMMARY OF THE INVENTION The flatness of the rolled metal strip is an important quality feature when rolling metal strips. It must in particular be avoided that the rolled metal strip becomes undulated after rolling. This set of issues likewise arises when cold-rolling steel and when hot-rolling aluminum. However, while the above-mentioned design embodiment of a rolling device is known in the context of the cold-rolling of steel, a rolling device of this type cannot readily also be used in the hot-rolling of aluminum. There are various reasons for this. One reason lies in that an aluminum strip has different physical properties and thus has a different oscillating behavior, for example different inherent frequencies, than a steel strip in the case of an identical geometry of the rolling device. In particular, the inherent frequencies in an aluminum strip are significantly lower than in a steel strip. In order to avoid interferences by inherent frequencies of the aluminum strip, a significantly lower frequency of the excited mechanical oscillation would have to be chosen in an aluminum strip than in a steel strip. For practical reasons, this theoretical possibility of operating at a lower frequency has proven inexpedient. A further reason lies in that trimming of the lateral edges of the aluminum strip is necessary after the hot-rolling of an aluminum strip. For this purpose, a trimming device by means of which a band of the metal strip is in each case severed on both sides of the aluminum strip is disposed on the outlet side of the of the roll stand in a rolling device for hot-rolling an aluminum strip. However, at least the peripheral regions of the aluminum strip are excited to mechanically oscillate as a result of the cutting procedure associated with the trimming. These oscillations interfere with the correct detection of the amplitudes of the excited mechanical oscillation at least in the peripheral regions of the aluminum strip and therefore falsify the result. Therefore, a detection by way of contact by means of a segmented tension measurement roll takes place for detecting the flatness of an aluminum strip. This solution has various disadvantages. For example, there is the risk of scratching or otherwise damaging the surface of the aluminum strip. Furthermore, the measurement is relatively inaccurate. Moreover, the use of a segmented tension measurement roll is cost-intensive. Finally, there is the risk of damage to the sensors of the segmented tension measurement roll. The object of the present invention lies in achieving possibilities by means of which a rolling device of the type mentioned at the outset can be modified in such a manner that said invention can be used in a rolling device for a hot aluminum strip. The object is achieved by a rolling device having the claimed features. Advantageous design embodiments of the rolling device are the subject matter of the dependent claims. According to the invention, a rolling device of the type mentioned at the outset is designed in that the rolling device has a trimming device which is disposed on the outlet side of the roll stand and by means of which one band of the metal strip is in each case able to be severed on both sides of the metal strip