Control method for a rolling train

Patent metadata

Field	Value
Publication number	US-9547290-B2
Application number	US-201214119972-A
Country	US
Kind code	B2
Filing date	May 4, 2012
Priority date	May 24, 2011
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

Based on an actual temperature upstream of a roll stand, a predicted temperature is estimated for when strip sections of the strip will roll through the roll stand. The predicted temperature is used to predict material moduli, which is used to control a regulating device that influences a roll gap for the roll stand and to parameterize a roll gap control system. A roll gap profile is predicted based on the predicted temperatures, and is compared with a nominal roll gap profile. A regulating variable that influences a profile of a roll gap is set. The regulating variable is then corrected based on the comparison with the nominal roll gap profile. The predictions are made using a prediction horizon corresponding to a plurality of consecutive sections of the strip. Control is performed for both an operator side and a drive side of the strip.

First claim

The invention claimed is:

1. A control method for a rolling mill train, comprising:
determining actual temperatures respectively for strip sections of a strip upstream of a first roll stand of the rolling mill train;
predicting predicted temperatures respectively for the strip sections when the strip sections are rolled in the first roll stand, the predicted temperatures being predicted using a strip model, the predicted temperatures being based on the actual temperatures, the predicted temperatures being predicted using a first prediction horizon corresponding to a plurality of strip sections to be rolled in the first roll stand;
predicting, using the predicted temperatures, a respective current operator-side and a respective current drive-side material modulus for the strip sections when the strip sections are rolled in the first roll stand, the material moduli describing how the strip sections respond to rolling;
setting a manipulated variable characteristic, the manipulated variable characteristic being a sequence of values set respectively for the strip sections corresponding to the first prediction horizon, the manipulated variable characteristic being a characteristic that would, if supplied to an adjusting device, have an influence on a profile of a roll gap formed by work rolls of the first roll stand;
predicting a respective predicted roll gap profile formed by the work rolls of the first roll stand at the time of rolling of the respective strip section, the predicted roll gap profile being predicted using a roll stand model, the predicted temperatures of the strip sections, the material moduli and the manipulated variable characteristic set for the strip sections corresponding to the first prediction horizon;
optimizing the manipulated variable characteristic based on the predicted roll gap profile for the strip sections and a respective setpoint roll gap profile, the manipulated variable characteristic being optimized to produce an optimized manipulated variable characteristic;
using a current value of the optimized manipulated variable characteristic as a control parameter; and
controlling the adjusting device acting on the first roll stand during rolling of the respective strip section, the adjusting device being controlled using the control parameter, the adjusting device influencing the roll gap of the first roll stand on the operator and the drive side, wherein
predicting predicted temperatures comprises predicting temperatures that are spatially resolved in a strip width direction, and
the optimized manipulated variable characteristic for a specific strip section is produced by optimizing the whole sequence of values set respectively for the strip sections corresponding to the first prediction horizon.

2. The control method as claimed in claim 1 , wherein
the strip model comprises a material model,
a predicted material property other than temperature is predicted using the material model, for the strip sections when the respective strip section is rolled in the first roll stand, and
the predicted material property is taken into account to determine the control parameter.

3. The control method as claimed in claim 1 , wherein
determining actual temperatures comprises determining actual temperatures that are spatially resolved in the strip width direction, and
the predicted temperatures and the actual temperatures are spatially resolved in the strip width direction so as to relate to at least the operator side and the drive side.

4. The control method as claimed in claim 1 , wherein
the predicted temperatures are supplied to a rolling force model,
the rolling force model is used to predict a predicted rolling force required for rolling the respective strip section in the first roll stand, the predicted roll force being predicted using the predicted temperatures for the strip sections corresponding to the first prediction horizon, and
the predicted roll gap profile is predicted using the roll stand model and the predicted rolling force.

5. The control method as claimed in claim 1 , wherein
the adjusting device comprises a roll cooling device controlled in a spatially resolved manner in a strip width direction.

6. The control method as claimed in claim 1 , wherein
a second roll stand downstream of the first roll stand of the rolling mill train has a second adjusting device and a second gap control system,
the second adjusting device is controlled using a second prediction horizon and a second control parameter,
the second gap control system is parameterized using the second prediction horizon,
the strip sections are rolled from a first entry thickness to a first exit thickness in the first roll stand and from a second entry thickness to a second exit thickness in the second roll stand, and
the control method used for the first prediction horizon and the first roll stand is also used for the second prediction horizon and the second roll stand, to control the second adjusting device.

7. The control method as claimed in claim 6 , wherein
the first exit thickness or the second entry thickness are determined on a strip section specific basis.

8. The control method as claimed in claim 6 , wherein
the second prediction horizon is dimensioned such that during the second prediction horizon a plurality of strip sections are rolled both in the first roll stand and the second roll stand.

9. The control method as claimed in claim 1 , wherein
the control computer uses the strip model and an additional model to determine the control parameter,
the strip model or the additional model is used as a parameterizable model,
the parameterizable model is parameterized by a model parameter additionally to values determined by the strip model or the additional model when determining the material moduli, determining in real-time functional dependencies of said values of the model parameter,
an expected measured value and a functional dependence of the expected measured value on the model parameter are determined for the strip sections in real time using the predicted temperatures, the material moduli, the predicted roll gap, and the manipulated variable characteristic,
a corresponding actual measured value is acquired for the strip sections in each case in real time using a measuring device disposed upstream, on or downstream of the first roll stand,
a corrected model parameter is determined based on the actual measured value, the expected measured value and the functional dependence of the expected measured value on the model parameter,
the parameterizable model is re-parameterized based on the corrected model parameter, and
the predicted temperatures, the material moduli, the predicted roll gap, and the manipulated variable characteristic are adjusted in real time as part of producing the control parameter using the parameterizable model.

10. A non-transitory computer readable storage medium storing a computer program which when executed by a control computer for a rolling mill train, causes the control computer to carry out a control method, the control method comprising:
determining actual temperatures respectively for strip sections of a strip upstream of a first roll stand of the rolling mill train;
predicting predicted temperatures respectively for the strip sections when the strip sections are rolled in the first roll stand, the predicted temperatures being predicted using a strip model, the predicted temperatures being based on the actual temperatures, the predicted temperatures being predicted using a first prediction horizon corresponding to a plurality of strip sections to be rolled in the first roll stand;
predicting, using the predicted temperatures, a respective curre

Assignees

• Dagner Johanned
• GRüSS ANSGAR
• Primetals Technologies Germany Gmbh

Inventors

• Dagner Johanned
• GRüSS ANSGAR

Classifications

• B21B37/58 Primary

  Roll-force control; Roll-gap control {(B21B38/105 takes precedence)} · CPC title

• B21B2261/21

  Temperature profile · CPC title

• G05B15/02 Primary

  electric · CPC title