EP0108379B1 - Verfahren und Regelkreis zum Regeln der Zugspannungsverteilung beim Kaltwalzen von Bändern - Google Patents

Verfahren und Regelkreis zum Regeln der Zugspannungsverteilung beim Kaltwalzen von Bändern Download PDF

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Publication number
EP0108379B1
EP0108379B1 EP19830110911 EP83110911A EP0108379B1 EP 0108379 B1 EP0108379 B1 EP 0108379B1 EP 19830110911 EP19830110911 EP 19830110911 EP 83110911 A EP83110911 A EP 83110911A EP 0108379 B1 EP0108379 B1 EP 0108379B1
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EP
European Patent Office
Prior art keywords
strip
tensile stress
distribution
tensile
rolling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19830110911
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German (de)
English (en)
French (fr)
Other versions
EP0108379A2 (de
EP0108379A3 (en
Inventor
Eberhard Dr.-Ing. Neuschütz
Bernd Dr.-Ing. Berger
Gert Dipl.-Ing. Mücke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BFI VDEH Institut fuer Angewandte Forschung GmbH
Original Assignee
BFI VDEH Institut fuer Angewandte Forschung GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BFI VDEH Institut fuer Angewandte Forschung GmbH filed Critical BFI VDEH Institut fuer Angewandte Forschung GmbH
Publication of EP0108379A2 publication Critical patent/EP0108379A2/de
Publication of EP0108379A3 publication Critical patent/EP0108379A3/de
Application granted granted Critical
Publication of EP0108379B1 publication Critical patent/EP0108379B1/de
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/28—Control of flatness or profile during rolling of strip, sheets or plates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/30—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a non-continuous process
    • B21B1/32—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a non-continuous process in reversing single stand mills, e.g. with intermediate storage reels for accumulating work
    • B21B1/36—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a non-continuous process in reversing single stand mills, e.g. with intermediate storage reels for accumulating work by cold-rolling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B13/00—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories
    • B21B13/14—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories having counter-pressure devices acting on rolls to inhibit deflection of same under load; Back-up rolls
    • B21B13/147—Cluster mills, e.g. Sendzimir mills, Rohn mills, i.e. each work roll being supported by two rolls only arranged symmetrically with respect to the plane passing through the working rolls

Definitions

  • the invention relates to a method for regulating the tensile stress distribution during cold rolling of strips, the tensile stress distribution on at least one side of a roll stand being determined from the strip thickness and the measured values from force transducers spaced axially across the roll width, and for adjusting the tensile stress distribution a controller and dependent actuators for the roll gap, which act differentially in the axial direction of the work rolls, are provided.
  • the invention relates to a rolling mill with a control loop, consisting of a controller, a device for determining the tensile force distribution in the outlet, which is connected to the controller, which, via an auxiliary control loop, acts on the actuators of the roll gap which act differentially in the axial direction of the rolls acts, the setting of which is attributed to the auxiliary control loop, to carry out the aforementioned method.
  • the tensile stress distribution can be changed in a known manner by influencing the roll gap differently over the bandwidth by means of suitable actuators.
  • a different deflection of the work rolls can be achieved by positively or negatively bracing the roll journals of opposing rolls. This essentially enables the setting of curved roll gaps and a corresponding course of the tensile stress distribution.
  • By simply pivoting the roll axes on the other hand, a straight-line change of the roll gap across the width can be brought about.
  • Locally differentiated changes can be achieved by means of a thermal control, in which support and / or work rolls are cooled or heated. Hollow rolls can be changed in their bombage by "pumping up", whereby their cavities are placed under different tensions.
  • a method for determining the tensile stress distribution during cold rolling is described in "Stahl und Eisen", 1977, pages 1029/1031.
  • a deflecting measuring roller with axially spaced tension sensors is used to record the tension distribution as a measure of length deviations and thus flatness in a three-stand cold rolling mill between the last rolling stand and the tension rollers.
  • a method of the type described in the introduction is known from "Iron and Steel Engineer", June 1979, pages 55 to 60.
  • the tensile stress distribution is monitored on the outlet side of the roll stand by means of a deflection measuring roller, the measured values of which are decisive for the actuation of the actuators. Basically, it is based on a uniform tension tension across the bandwidth.
  • the controller working with the input of the tension distribution can also act via an auxiliary control loop on Stetigii ß which acts differentially in the axial direction of the roll and of the roll gap, the setting of which is attributed to the auxiliary control loop.
  • this auxiliary control loop there is the possibility of manually specifying setpoints for the actuators.
  • the values determined for the settings of the actuators on the basis of the tension distribution are subject to storage dependent on the rolling speed, so that the storage has a representative signal ready for the deviation from the average tension.
  • the actuators of a rolling mill are adjusted by the tension distribution determined via a deflection measuring roller.
  • the strip thickness measured across the bandwidth at various points is also taken into account.
  • the invention has for its object to provide a method of the type described in the introduction and a rolling mill with a control loop in such a way that malfunctions during rolling are avoided.
  • the conditions of the flatness of the rolling stock should also be observed. Furthermore, it should be possible to achieve trouble-free rolling with high degrees of deformation through high tensile stresses.
  • a distribution of the tensile stress is therefore first measured at the outlet by means of the tension transducers spaced apart in the axial direction of the rollers.
  • the difference to the inlet tension distribution is either determined by tension sensors located on the inlet side of the roll stand, spaced apart in the axial direction, or determined in the case of reversing roll stands on the basis of stored measured values which were measured and stored in the previous rolling phase.
  • the method according to the invention can thus be expediently adapted to the operating conditions.
  • the tensile stress measurements to be carried out in connection with the invention can expediently be obtained on a deflecting measuring roller which has spacing means which are spaced apart in the axial direction.
  • This if necessary in conjunction with a measuring roller located on the other side of the roll stand or with a memory, allows both the measurements for the determination of the congestion of the flatness of the strip and finally also the elastic roll deformation.
  • the material thickness, the tensile forces and the force distribution at the inlet and outlet of the roll stand and the bandwidth and the strip position are only taken into account at the outlet of the roll stand.
  • suitable measuring sensors for example optical devices, can continuously detect the roll gap and introduce the measured values into a control loop in which the actuators are changed by corresponding amounts that the elastic deromations are compensated.
  • this requires additional measuring and computing devices.
  • a rolling mill with a control circuit is introductory and described in claim 8, in which the tensile force distribution at the outlet is fed back to the controller as control variables, and in which an auxiliary control circuit for the adjustment of the axial spaced actuators is provided, to which the actuator positions are returned.
  • the actuators can be acted on practically without dead time.
  • a measured tension distribution at the inlet is used to specify a target function of the tension distribution at the outlet.
  • the latter is used in conjunction with a measured thickness profile of the incoming strip to determine the position of the actuators.
  • the presetting part is expediently connected to the auxiliary control circuit as a precontrol part during the rolling after the control function of the control loop has been inserted, only the respective changes in the values of the strip thickness profile, the tensile force distribution, the strip position and the strip width available for the entry side being taken into account.
  • the method according to the invention is fundamentally possible in any rolling mill in which a differentiated action can be exerted on the roll gap in the axial direction. This method can be used particularly advantageously in the case of a reversible roll stand with supported work rolls, which is arranged between the brake reel and the drive reel, which can be reversed during reversing.
  • a deflecting measuring roller having the axially spaced measuring transducers is only required on one side of the rolling stand if the measured values are transmitted to the controller in the rolling phase in which the measuring roller is located at the outlet of the rolling stand and in the subsequent phase in which the After reversing the measuring roller is located at the inlet of the roll stand, the pilot part for the tensile stress distribution on the outlet side is transferred. You then save both the space and the effort for a second deflecting measuring roller or the like.
  • the action on the contour of the roll gap is particularly effective in the case of a multi-roll stand, the support rolls of which are axially spaced apart and can be adjusted separately.
  • the strip 1 recognizable in cross section is deformed by the work rolls 2.
  • the work rolls 2 are fixed in position by conical rolls 3.
  • the latter are in turn supported by the intermediate rollers 4, which can be adjusted using the support rollers 5.
  • the support rollers 5 are each provided with a support saddle 6, as can also be seen from FIG. 2.
  • the eccentrics 7 for the bearing of each support roller 5 are adjustable so that the bearing axles 8 can be adjusted. This makes it possible to adjust the support rollers 5 in the direction of the double arrows 9. They thus act in an axially differentiated manner on the intermediate rolls 4, which in turn change the roll gap between the work rolls 2 via the cone rolls 3.
  • the rolling stand 10 can be seen, which is shown schematically as a reversible four-high stand.
  • the strip is rolled in the direction of arrow 11.
  • the tension sensors which are spaced apart in the axial direction, are implemented in the deflecting measuring roller 12 in the outlet, which corresponds to the deflecting measuring roller 12 'in the inlet.
  • the strip 1 is subject to the drive reel 13, the Brake reel 14 and the specification of the roll gap defined tensile force distribution, from this the tensile stress distribution is calculated, for which a target specification is determined, on the basis of which the controller influences the actuators of the rolling mill, as can be seen from the left part of FIG. 3.
  • the right part illustrates the addition of the procedure through presetting and feedforward control.
  • the tensile force distribution determined by the measuring roller 12 'in the inlet is taken into account both for the pilot control 20 and for the calculation of the target tension distribution 21. Likewise, there is still the measurement for the thickness profile 22 in the inlet, which is also taken into account in the pilot control 20 and in the calculation of the target stress distribution 21.
  • the output of the calculation of the target voltage distribution leads to the presetting 23 in order to lead from there together with the precontrol 20 to the setting of the actuator positions 24.
  • the setting of the actuator positions 24 also takes place on the basis of a control 25, to the input of which the calculation of the target voltage distribution 26 leads on the basis of the measurement on the outlet side of the tensile force distribution by means of the measuring roller 12.
  • FIG. 6 the presetting of the tensile stress distribution is formed in an analogous manner to the regulation of the tensile stress distribution, FIG. 6 additionally showing the possibility of storing the actual values, which can also be used when one wants to record the change in band position and band width.
  • FIG. 6 also shows blocks that are not shown in FIG. 3 for reasons of clarity.
  • FIG. 6 shows that the calculation of the target stress distribution 21 is preceded by the calculation of the actual stress distribution 27 at the inlet, which is supplied not only with the tensile force distribution of the inlet but also with the thickness profile measurement 22 of the inlet.
  • the calculation of the target tension distribution 21 also includes the measurement of the rolling force 28, as well as the calculation of the actual tension distribution, the actual bandwidth and the actual strip position derived from block 29.
  • the thickness in the outlet 30 and the tensile force distribution in the outlet 31 are supplied to this block 29 as measured values.
  • the actual values formed in block 29 can be stored in memory 32, from where the calculation of the change in bandwidth and band position 33 can be applied directly if, as mentioned, the band position and band width change are to be recorded. Otherwise, the output of the calculation of the actual values in block 29 is used to calculate the target-actual difference of the voltage distribution 34, to which the calculation of the target voltage distribution 21 is also switched, and which in turn is used to calculate the change in bandwidth and band position 33 acted upon. This is followed by the calculation of the change in thickness profile at the outlet through material spreading 35, which is followed by the calculation of the actuator adjustment amounts 36. This is followed by the calculation and finally the setting of the actuator positions 37, which closes the control loop.
  • the presetting part of the control circuit is shown in more detail in FIG.
  • the nominal tension distribution at the outlet 21 are supplied with the tensile force of the outlet 38 and the thickness of the outlet 39 as well as the tensile force distribution, bandwidth and band position of the inlet and the rolling force 28 ascertained with the measuring roller 12 '.
  • the output of the calculation of the target stress distribution in the outlet leads to the calculation of the change in thickness profile at the outlet through material spreading 40, for which the calculation of the thickness profile at the outlet with constant volume 41 is taken into account on the basis of the thickness profile measurement 22 in the inlet.
  • the calculation of the thickness profile changes at the outlet by material spreading in block 40 leads to the calculation of the actuator target positions 42 and finally to the adjustment of the actuator positions 43, which closes the control loop.
  • the target distribution of the tensile stress at the outlet can be determined, which, taking into account the thickness profile with constant volume and the change in thickness profile due to material spreading, enables the position specification of the actuators to be calculated.
  • the auxiliary control circuit shown in FIG. 7 serves to take these values into account for setting the actuator positions, in which the set positions are returned. The dead time can be practiced in this way switch off, so that the control loop responds to even very short-term operational changes with sufficient accuracy by adjusting the actuators to the exact size.
  • the pilot control part according to FIG. 8 allows the aforementioned changes to be taken into account. Basically, the same organs are used as for the pilot control part of FIG. 7 and the control circuit of FIG. 6, so that this advantageous embodiment requires only an insignificant additional effort.
  • the inlet-side calculation of the actual tension distribution, the actual belt width and the actual belt position in block 44 are the tensile force distribution of the inlet based on the measurement with the measuring roller 12 ', the thickness in the inlet 50 and the strip thickness in the outlet 46 fed.
  • the actual values calculated in block 44 can be stored in memory 45 and can be used from there or also directly for calculating the change in voltage distribution, bandwidth and band position 46 in block 49.
  • the output of block 49 together with the thickness profile measurement 22 in the inlet, stores both the actual thickness profile 47 and the calculation of the change in thickness profile for the inlet and outlet 48.
  • the latter calculation 48 together with the rolling force 28, performs the calculation of the change in thickness profile at the outlet Material spread 40 and from there to calculate the actuator adjustment amounts 36, and on the basis of this calculation 36 there is calculation and adjustment of the actuator positions 37, which also closes this control loop.
  • FIG. 4 shows, over the bandwidth x, the profile ⁇ A of the tensile stress distribution, which in this case is lower in the middle than at the edges. If, however, edge cracks in the strip are to be obtained in the manner mentioned, and if the greatest possible forming and tensile stress are to continue to be rolled, the course ⁇ A should be reversed.
  • the lower dashed line shows the tension curve ⁇ E inlet.
  • Fig. 5 shows the representation of the tensile stress distribution across the width, which is only related to the differences in the tensile stress curves. This makes it particularly clear that the regulation must move in the direction of the constancy ⁇ if one wishes to avoid the congestion of the fold.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Metal Rolling (AREA)
  • Metal Rolling (AREA)
EP19830110911 1982-11-03 1983-11-02 Verfahren und Regelkreis zum Regeln der Zugspannungsverteilung beim Kaltwalzen von Bändern Expired EP0108379B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19823240602 DE3240602A1 (de) 1982-11-03 1982-11-03 Verfahren zum regeln der zugspannungsverteilung beim kaltwalzen von baendern
DE3240602 1982-11-03

Publications (3)

Publication Number Publication Date
EP0108379A2 EP0108379A2 (de) 1984-05-16
EP0108379A3 EP0108379A3 (en) 1986-01-15
EP0108379B1 true EP0108379B1 (de) 1989-08-02

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Application Number Title Priority Date Filing Date
EP19830110911 Expired EP0108379B1 (de) 1982-11-03 1983-11-02 Verfahren und Regelkreis zum Regeln der Zugspannungsverteilung beim Kaltwalzen von Bändern

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EP (1) EP0108379B1 (ja)
JP (1) JPS59130615A (ja)
DE (1) DE3240602A1 (ja)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008015828A1 (de) 2007-09-26 2009-04-02 Sms Demag Ag Walzvorrichtung und Verfahren für deren Betrieb
AU2005297538B2 (en) * 2004-10-13 2010-07-01 Primetals Technologies Austria GmbH Method and device for continuously producing a thin metal strip

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3430034A1 (de) * 1984-08-16 1986-02-27 Mannesmann AG, 4000 Düsseldorf Planheitsregelung an bandwalzgeruesten
DE3823202A1 (de) * 1988-07-08 1990-01-11 Betr Forsch Inst Angew Forsch Verfahren zum kaltwalzen von blechen und baendern
DD294883A5 (de) * 1990-06-05 1991-10-17 Freiberg Bergakademie Verfahren zur erzeugung von eigenspannungsarmen band beim walzen
DE4413913C2 (de) * 1993-04-30 1998-10-15 Krupp Hoesch Stahl Ag Verfahren zum Verhindern eines Faltungsstaus beim Walzen von Metallband
US8205474B2 (en) * 2006-03-08 2012-06-26 Nucor Corporation Method and plant for integrated monitoring and control of strip flatness and strip profile
US7849722B2 (en) 2006-03-08 2010-12-14 Nucor Corporation Method and plant for integrated monitoring and control of strip flatness and strip profile
CN104646431B (zh) * 2015-03-05 2017-01-11 北京科技大学 一种消除双机架铝冷连轧机组负荷漂移的控制方法
DE102020205120A1 (de) * 2020-04-22 2021-10-28 Sms Group Gmbh Verfahren zum Betreiben einer Metallbandbearbeitungsanlage sowie Metallbandbearbeitungsanlage
CN113083907B (zh) * 2021-03-29 2022-07-19 广西北港不锈钢有限公司 一种不锈钢板材偏心轧制线计算方法

Family Cites Families (7)

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Publication number Priority date Publication date Assignee Title
US3315506A (en) * 1964-01-09 1967-04-25 Westinghouse Electric Corp Workpiece tension and shape control method and apparatus
AT345237B (de) * 1976-12-28 1978-09-11 Voest Ag Vorrichtung zum walzen von band- oder tafelfoermigem walzgut
JPS5467549A (en) * 1977-11-09 1979-05-31 Mitsubishi Electric Corp Shape controll of rolled material
DE2911621A1 (de) * 1978-03-31 1979-10-04 Loewy Robertson Eng Co Ltd Verfahren zum betreiben eines walzwerks zur erzeugung von metallbaendern
JPS5542143A (en) * 1978-09-19 1980-03-25 Nippon Steel Corp Shape control method of strip
SE446952B (sv) * 1980-04-25 1986-10-20 Asea Ab Regleranordning vid band- eller platvalsverk
DE3020669C2 (de) * 1980-05-30 1984-02-16 Küsters, Eduard, 4150 Krefeld Verfahren zur Steuerung der Liniendruckverteilung in einem Kalander sowie ensprechender Kalander

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2005297538B2 (en) * 2004-10-13 2010-07-01 Primetals Technologies Austria GmbH Method and device for continuously producing a thin metal strip
AU2005297538B8 (en) * 2004-10-13 2010-07-15 Primetals Technologies Austria GmbH Method and device for continuously producing a thin metal strip
DE102008015828A1 (de) 2007-09-26 2009-04-02 Sms Demag Ag Walzvorrichtung und Verfahren für deren Betrieb

Also Published As

Publication number Publication date
EP0108379A2 (de) 1984-05-16
EP0108379A3 (en) 1986-01-15
DE3240602C2 (ja) 1993-06-09
JPS59130615A (ja) 1984-07-27
DE3240602A1 (de) 1984-06-14

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