Primetals Technologies Germany Gmbh

Primetals Technologies Austria Gmbh

Siemens Aktiengesellschaft

Daniel Kotzian

Wilfried Tautz

Andreas Maierhofer

Matthias Kurz

Ansgar Grüss

Bernhard Weisshaar

Klaus Loehe

Rainer Burger

Martin Kerschensteiner

Matthias Dressler

Daniel Ott

Mirko Tunk

Srdan Sekulic

Martin Schönherr

A roll stand of a rolling mill is supplied with a metal strip by an upstream supply device at an in-feed speed (v), with said metal strip being rolled in the roll stand. A measuring device between the supply device and the roll stand detects a respective thickness value (d) of the metal strip for consecutive sections of the metal strip and supplies said value to a control device of the rolling mill. The control device determines final thickness deviations based on the preliminary thickness deviations. The control device determines a respective control value (A, A) for the roll stand and/or the supply device for the sections of the metal strip based on the final thickness deviation of the respective section of the metal strip and the final thickness deviations of multiple preceding and/or subsequent sections of the metal strip.

Rolling taking frequency behavior into account

A control device () for a roll stand (). During rolling of a metal strip () in the roll stand (), the device receives measurement data (M) for a lateral position (y) of the metal strip () on the inlet side and/or outlet side of the roll stand (). Taking into account parameters (P) of the stand regulator () on the basis of the deviation in the lateral position (y) from a target position (y*), a stand regulator () of the control device () determines a tilt value (δs) for the roll stand () and controls the roll stand () accordingly. The control device () determines at least one variable (V, V, Q, Q) from which it is derived, for both strip edges () of the metal strip (), whether the metal strip () forms an undulation () in the region of the particular strip edge (). As soon as the metal strip () forms an undulation () in the region of one of the strip edges (), the control device () varies at least one of the parameters (P) of the stand regulator (), such that the stand regulator () determines the tilt value (δs), starting from the variation in the at least one parameter (P), and taking into account the changed parameter (P).

Preventing undulations when rolling metal strips

Before the rolling of a metal strip on a finishing train, the actual width and actual temperature of portions of the metal strip are respectively detected. The portions of the metal strip are tracked while they run through the finishing train. The rolling stands are respectively assigned width controlling devices which determine the setpoint width and the actual width after the rolling in the assigned rolling stand, and a downstream additional setpoint value, by which the desired tension downstream of the assigned rolling stand is corrected in order to bring the actual width closer to the setpoint width. The downstream additional setpoint value is both taken into account in the determination of the actual width and fed to a tension controller, which sets an actual tension, in the metal strip downstream of the assigned rolling stand, in accordance with the corrected setpoint tension. Determining the downstream additional setpoint value by the difference between the setpoint width and the actual width of a portion of the metal strip.

Width setting on a finishing train

A metal band is first rolled in a front and then in a rear (downstream) roll stand of a multi-stand rolling train. A looper between the roll stands may detect a band tension in the metal band. The band tension is supplied to a first and a second tension controller to determine an application additional target value and a speed additional target value. The second tension controller may only determine a value less than or greater than 0, as the speed additional target value, if the band tension is above or below an upper or lower band tension limit. Otherwise, the speed additional target value may be 0. The first tension controller is also supplied with a target tension that falls between the band tension limits. The application additional target value may be used to act on the rear roll stand.

Robust band tension control

Growing community of inventors

Forchheim, Germany

Daniel Kotzian