EP3328565B1 - Roller grinder for targeted prevention of quarter waves - Google Patents

Description

• wobei das Walzgerüst Walzgerüstständer aufweist,
• wobei in den Walzgerüstständern Arbeitswalzen oder Arbeitswalzen und Stützwalzen oder Arbeitswalzen, Zwischenwalzen und Stützwalzen gelagert sind,
• wobei die in den Walzgerüstständern gelagerten Walzen um eine jeweilige Rotationsachse rotierbar sind,
• wobei in dem Fall, dass in den Walzgerüstständern Arbeitswalzen oder Arbeitswalzen und Stützwalzen gelagert sind, die Arbeitswalzen und in dem Fall, dass in den Walzgerüstständern Arbeitswalzen, Zwischenwalzen und Stützwalzen gelagert sind, die Arbeitswalzen oder die Zwischenwalzen in Richtung ihrer jeweiligen Rotationsachse, d.h. axial, gegeneinander verschiebbar sind,
• wobei die axial gegeneinander verschiebbaren Walzen jeweils eine wirksame Ballenlänge aufweisen,
• wobei die axial gegeneinander verschiebbaren Walzen jeweils eine gekrümmte Kontur aufweisen, die sich über die gesamte wirksame Ballenlänge erstreckt.

The present invention is based on a rolling mill for the production of flat rolled stock, in particular of metal strip,

• wherein the rolling stand comprises rolling stand stands,
• wherein work rolls or work rolls and back-up rolls or work rolls, intermediate rolls and back-up rolls are mounted in the rolling stand stands,
• wherein the rollers mounted in the rolling mill stands are rotatable about a respective axis of rotation,
• wherein, in the case where work rolls or work rolls and back-up rolls are mounted in the stands, the work rolls and, in the case where work rolls, intermediate rolls and back-up rolls are supported in the stand stands, the work rolls or the intermediate rolls in the direction of their respective axis of rotation, ie axially, are mutually displaceable,
• wherein the axially mutually displaceable rollers each have an effective bale length,
• wherein the axially mutually displaceable rollers each have a curved contour which extends over the entire effective bale length.

Such a rolling mill is for example from the WO 03/022 470 A1 known.

In the known rolling stand, the contour of one of the two axially mutually displaceable rollers is formed by a first basic function, the contour of the other of the two axially mutually displaceable rollers by a second basic function. The basis functions are functions of the place seen in the direction of the respective axis of rotation. They are further determined such that they complement each other in the unloaded state of the two axially mutually displaceable rollers in a certain relative axial position and complementary at an outgoing from this axial position displacement Shifting direction form a convex or a concave roll gap profile.

To produce a flat rolling stock - for example, a metal strip or a heavy plate - with a defined cross-sectional profile, it is necessary to use contour-influencing measures. Examples of such measures are the use of roll bending devices, by means of which the rolling force application to the rolling stock and the thickness distribution over the width of the rolling stock can be selectively influenced.

It is known to use for influencing the cross-sectional profile of work rolls whose bale contour is like a bottle neck. Examples of such courses are known to those skilled in the art under the terms CVC (CVC is a registered trademark of SMS Siemag AG) and SmartCrown (SmartCrown is a registered trademark of the Applicant). In particular, the course of a SmartCrown contour is described in detail in the introduction WO 03/022 470 A1 explained.

• wobei das Walzgerüst Arbeitswalzen aufweist, die sich an Stützwalzen oder Zwischenwalzen und Stützwalzen abstützen,
• wobei die Arbeitswalzen und/oder die Zwischenwalzen und/ oder die Stützwalzen im Walzgerüst gegenseitig axial verschiebbar angeordnet sind,
• wobei die Arbeitswalzen und die Stützwalzen sowie - sofern vorhanden - die Zwischenwalzen jeweils eine wirksame Ballenlänge aufweisen,
• wobei jede Walze mindestens eines aus einer Stützwalze und einer Arbeitswalze oder aus einer Stützwalze und einer Zwischenwalze gebildeten Walzenpaares eine über die gesamte wirksame Ballenlänge verlaufende gekrümmte Kontur aufweist,
• wobei die Kontur der Stützwalze durch eine Überlagerung einer Basisfunktion mit einer konkaven oder konvexen Zusatzfunktion gebildet ist,
• wobei eine Kontur der Stützwalze gemäß der Basisfunktion in einem unverschobenen Zustand zur benachbarten Arbeitswalze oder Zwischenwalze komplementär verläuft und bei einer Verschiebung je nach Verschieberichtung ein konvexes oder ein konkaves Differenzprofil bildet.

The bottle neck-like course of the bale contour is used not only on work rolls but also on intermediate rolls and back-up rolls. From the WO 2011/069 756 A1 For example, a rolling mill for the production of flat rolling is known,

• the rolling stand having work rolls supported on back-up rolls or intermediate rolls and back-up rolls,
• wherein the work rolls and / or the intermediate rolls and / or the support rolls are mutually axially displaceable in the roll stand,
• wherein the work rolls and the backup rolls and, if present, the intermediate rolls each have an effective bale length,
• wherein each roller of at least one pair of rollers formed from a back-up roll and a work roll or from a back-up roll and an intermediate roll has a curved contour extending over the entire effective length of the bale,
• wherein the contour of the support roller is formed by a superposition of a basic function with a concave or convex additional function,
• wherein a contour of the support roller according to the basic function in a non-displaced state to the adjacent work roll or intermediate roller extends complementary and forms a convex or a concave difference profile upon displacement depending on the displacement direction.

The superimposition of the basic function with the additional function serves the purpose of reducing the maximum pressure acting on the work roll and the backup roll or on the intermediate roll and the backup roll, thereby increasing roll life and avoiding roll breaks as far as possible. The additional function is a quadratic function.

• wobei das Walzgerüst Arbeitswalzen aufweist, die sich an Stützwalzen oder Zwischenwalzen und Stützwalzen abstützen,
• wobei die Arbeitswalzen und/oder die Zwischenwalzen jeweils eine wirksame Ballenlänge aufweisen,
• wobei die Arbeitswalzen und/oder die Zwischenwalzen eine über die gesamte wirksame Ballenlänge verlaufende gekrümmte Kontur aufweisen, die durch eine trigonometrische Funktion beschreibbar ist,
• wobei sich diese Ballenkonturen ausschließlich in einer bestimmten relativen Axialstellung der Walzen des Walzenpaares im unbelasteten Zustand komplementär ergänzen,
• wobei die Stützwalzen eine komplementäre Ballenkontur aufweisen und im unbelasteten Zustand eine teilweise oder vollständige Ergänzung der Ballenkonturen der Stützwalzen und der unmittelbar benachbarten Arbeitswalzen oder Zwischenwalzen auftritt.

From the WO 2007/144 162 A1 a rolling stand for the production of flat rolling is known,

• the rolling stand having work rolls supported on back-up rolls or intermediate rolls and back-up rolls,
• wherein the work rolls and / or the intermediate rolls each have an effective bale length,
• wherein the work rolls and / or the intermediate rolls have a curved contour extending over the entire effective bale length, which can be described by a trigonometric function,
• wherein these bale contours complement each other exclusively in a specific relative axial position of the rolls of the pair of rolls in the unloaded state,
• wherein the support rollers have a complementary bale contour and in the unloaded state, a partial or complete complement of the bale contours of the support rollers and the immediately adjacent work rolls or intermediate rollers occurs.

Of the WO 2007/144 161 A1 a similar disclosure can be found.

When rolling stock, it is usually the endeavor that the rolling stock after rolling has a predetermined profile and is still flat. Unevenness in the rolling stock can occur in particular if the rolling stock is relatively thin and the relative profile of the rolling stock is changed too strongly during the respective rolling pass, ie if the width of the rolling stock shows an uneven reduction in thickness or a reduction in the number of passes. Depending on the position of the impositions one speaks of edge, middle or quarter waves. Edge shafts and center shafts can be eliminated in the prior art with conventional actuators such as roll shifting and roll bending. This is much more difficult with quarter waves.

In the prior art, targeted suppression of quarter waves by means of zone cooling is known for cold rolling mills. When hot rolling a dynamic roll cooling can be used to suppress quarter waves. This dynamic roller cooling causes over the Walzgutbreite seen uneven cooling and thus a corresponding thermal crowning of the rolls. However, this type of influencing the crowning is relatively limited in their effectiveness and beyond sluggish. Furthermore, it is possible to suppress quarter waves by a targeted combination of displacement and bending of the work rolls. However, this presupposes that a sufficiently large adjustment range of the roll bending is present. However, in the prior art, roll bending is usually used primarily to be able to react to rolling force deviations during the rolling of the rolling stock, in particular to keep the relative or absolute rolling profile constant and to ensure flatness.

The object of the present invention is to provide a rolling mill, in which by axial displacement of rollers, the shape of the roll gap, ie the thickness profile of the roll gap over the bale length, is varied such that a highest quality standards fulfilling, flat and wave-free rolling is achieved.

The object is achieved by a rolling mill with the features of claim 1. Advantageous embodiments of the rolling stand according to the invention are the subject of the dependent claims 2 to 4.

• dass eine der beiden axial gegeneinander verschiebbaren Walzen eine erste Kontur aufweist, die durch eine Überlagerung einer ersten Basisfunktion und einer ersten Zusatzfunktion gebildet ist,
• dass die andere der beiden axial gegeneinander verschiebbaren Walzen eine zweite Kontur aufweist, die durch Überlagerung einer zweiten Basisfunktion und einer zweiten Zusatzfunktion gebildet ist,
• wobei die Basisfunktionen den Beziehungen $$\mathrm{B}1=+\mathrm{A}\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x+c\right)\right)-B\cdot \mathrm{<figure-callout\; id="2"\; label="x\; und\; B"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">x</figure-callout>}$$
  
  und $$\mathrm{B}$$$$\mathrm{}2=-\mathrm{A}\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x-c\right)\right)+B\cdot x$$
  
  oder den Beziehungen $$\mathrm{B}1=+\mathrm{A}\prime {\left(\mathrm{x}+\mathrm{<figure-callout\; id="5"\; label="c"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">c</figure-callout>}\right)}^5+\mathrm{A}{\left(\mathrm{x}+\mathrm{<figure-callout\; id="3"\; label="c"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">c</figure-callout>}\right)}^3-B\cdot \mathrm{<figure-callout\; id="2"\; label="x\; und\; B"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">x</figure-callout>}$$
  
  und $$\mathrm{B}$$$$\mathrm{}2=-\mathrm{A}\prime {\left(\mathrm{x}-\mathrm{<figure-callout\; id="5"\; label="c"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">c</figure-callout>}\right)}^5-\mathrm{A}{\left(\mathrm{x}-\mathrm{<figure-callout\; id="3"\; label="c"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">c</figure-callout>}\right)}^3+B\cdot x$$
  
  und die Zusatzfunktionen (Z1, Z2) den Beziehungen $$\mathrm{Z}1=-\alpha \cdot {\mathit{<figure-callout\; id="2"\; label="Cx"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Cx</figure-callout>}}^2-\beta <figure-callout\; id="4"\; label="\cdot \; Dx"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot </figure-callout>{\mathit{Dx}}^{}{\mathit{}}^4$$
  
  und $$\mathrm{Z}$$$$\mathrm{}2=-\left(2-\alpha \right)\cdot {\mathit{<figure-callout\; id="2"\; label="Cx"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Cx</figure-callout>}}^2-\left(2-\beta \right)<figure-callout\; id="4"\; label="\cdot \; Dx"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot </figure-callout>{\mathit{Dx}}^{}{\mathit{}}^4$$
  
  oder den Beziehungen $$\mathrm{Z}1=-\alpha \cdot C\cos \mathit{\lambda x}$$
  
  und $$\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}2=-\left(2-\alpha \right)\cdot C\cos \mathit{\lambda x}$$
  
  genügen, wobei
• B1 und B2 die erste und die zweite Basisfunktion sind,
• Z1 und Z2 die erste und die zweite Zusatzfunktion sind,
• A und A' Konturamplituden sind,
• ϕ ein Konturwinkel ist,
• L_Ref eine Referenzlänge ist,
• x der Ort bzw. die Axialposition, bezogen auf die Ballenmitte ist,
• c eine Konturverschiebung ist,
• B eine Kontursteigung ist,
• α und β Wichtungsfaktoren sind,
• C und D Anteilsfaktoren sind und
• λ ein Faktor ist.

According to the invention, a roll stand of the type mentioned is configured by

• in that one of the two axially displaceable rollers has a first contour, which is formed by a superimposition of a first basic function and a first additional function,
• that the other of the two axially displaceable rollers has a second contour, which is formed by superposing a second basic function and a second additional function,
• where the basic functions are relations $$\mathrm{B}1=+\mathrm{A}\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x+c\right)\right)-B\cdot x$$
  
  and $$\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">B</figure-callout>}2=-\mathrm{A}\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x-c\right)\right)+B\cdot x$$
  
  or the relationships $$\mathrm{B}1=+\mathrm{A}\text{'}{\left(\mathrm{x}+\mathrm{<figure-callout\; id="5"\; label="c"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">c</figure-callout>}\right)}^5+\mathrm{A}{\left(\mathrm{x}+\mathrm{c}\right)}^3-B\cdot x$$
  
  and $$\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">B</figure-callout>}2=-\mathrm{A}\text{'}{\left(\mathrm{x}-\mathrm{c}\right)}^5-\mathrm{A}{\left(\mathrm{x}-\mathrm{<figure-callout\; id="3"\; label="c"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">c</figure-callout>}\right)}^3+B\cdot x$$
  
  and the additional functions (Z1, Z2) the relations $$\mathrm{Z}1=-\alpha \cdot {\mathit{cx}}^2-\mathrm{<figure-callout\; id="4"\; label="\beta \; \cdot \; dx"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\beta \; </figure-callout>}\cdot {\mathit{dx}}^{}{\mathit{}}^4$$
  
  and $$\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}2=-\left(2-\alpha \right)\cdot {\mathit{cx}}^2-\left(2-\mathrm{<figure-callout\; id="4"\; label="\beta \; \cdot \; dx"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\beta \; </figure-callout>}\right)\cdot {\mathit{dx}}^{}{\mathit{}}^4$$
  
  or the relationships $$\mathrm{Z}1=-\alpha \cdot C\cos \mathit{\lambda x}$$
  
  and $$\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}2=-\left(2-\alpha \right)\cdot C\cos \mathit{\lambda x}$$
  
  suffice, where
• B1 and B2 are the first and second basic functions,
• Z1 and Z2 are the first and the second additional function,
• A and A 'are contour amplitudes,
• φ is a contour angle,
• L _{Ref is} a reference _length ,
• x is the location or axial position relative to the center of the bale,
• c is a contour shift,
• B is a contour slope,
• α and β are weighting factors
• C and D are proportional factors and
• λ is a factor.

Due to this design of the contours of the two axially mutually displaceable rollers quarter waves can be suppressed solely by the roll grinding. Because this grinding is achieved that the equivalent crown of the two axially against each other sliding rollers is provided with an offset. In general, the offset is positive, only negative in exceptional cases. The equivalent crowning is the crowning of conventional (that is, symmetrical) ground rolls, which give the same nip profile in the unloaded or load-free state.

It is possible that the contour shift lies within the actually achievable displacement range of the two rollers which are axially displaceable relative to one another. Alternatively, the contour shift may be outside the actual reachable displacement range. In the latter case, the two basic functions always form a convex or always a concave roll gap profile independently of the actual displacement. In this case, only in the mathematical sense, a sign reversal is possible.

The inventive design of the two axially displaceable rollers facilitates both the mathematical description of the contours of the two axially displaceable against each other Rolling as well as the manufacturing production of the contours of the two axially mutually displaceable rollers.

It is particularly advantageous if the additional functions are symmetrical to one another. By this configuration can be achieved in particular that the two axially mutually displaceable rollers can be ground in the same manner and only one of the two rollers must be installed with respect to the other rotated by 180 ° in the rolling mill.

It is possible that the roll stand has no further rolls other than the work rolls. As a rule, however, the work rolls are supported directly or via intermediate rolls on support rolls. In the case of the presence exclusively of back-up rolls (for example a quarto backbone), the contours of the back-up rolls can be provided with an inverse additional contour, so that the back-up rolls complement each other in an uncompressed, unloaded state. Alternatively, it is possible that the contours of the support rollers differ from those of the work rolls in particular by a concave difference. In the case of both back-up rolls and intermediate rolls (eg, a sexto-scaffold), the contours of the intermediate rolls may be different from those of the work rolls and / or back-up rolls by such a concave difference. By means of this embodiment, maximum pressures acting between adjoining rollers can be minimized.

FIG 1 und 2

jeweils ein Walzgerüst,

FIG 3 und 4

jeweils zwei Arbeitswalzen,

FIG 5

einen von zwei Arbeitswalzen gebildeten Walzspalt,

FIG 6

eine Arbeitswalze und eine Stützwalze und

FIG 7

eine Arbeitswalze, eine Zwischenwalze und eine Stützwalze.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the embodiments, which will be described in more detail in conjunction with the drawings. Here are shown in a schematic representation:

1 and 2

one rolling stand each,

3 and 4

two work rolls each,

FIG. 5

a nip formed by two work rolls,

FIG. 6

a work roll and a backup roll and

FIG. 7

a work roll, an intermediate roll and a backup roll.

In a rolling stand provided generally with the reference numeral 1, according to the FIG. 1 and 2 a flat rolling 2 rolled and thereby produced. The rolling stock 2 may consist in particular of metal, for example of aluminum or steel. It can be a band or a heavy plate.

According to the FIG. 1 and 2 has the rolling stand 1 rolling stand 3. In the rolling mill stands 3, a first and a second work roll 4, 5 are mounted. The work rolls 4, 5 are - as is common practice - stored in the rolling mill stands 3 such that the work rolls 4, 5 about a respective axis of rotation 6, 7 are rotatable. The rotation is effected by means of a common drive assigned to the work rolls 4, 5 or by drives assigned to each of the work rolls 4, 5. The drive is or the drives are not shown in the FIG.

The first work roll 4 is as shown in the FIG. 1 and 2 the upper work roll. Correspondingly, the second work roll 5 is the lower work roll. However, the reverse assignment is also possible.

It is possible that the roll stand 1 except the work rolls 4, 5 has no further rolls (Duogerüst). In general, however, support the work rolls 4, 5, as shown in the FIG. 1 and 2 on support rollers 8, 9 from. It is according to the illustration in FIG. 1 possible that the roll stand 1 except the work rolls 4, 5 and the support rollers 8, 9 has no further rolls (for example, in a Quartogerüst). In this case, the work rolls 4, 5 are supported directly on the support rollers 8, 9. Alternatively, it is - for example, in a Sextogerüst - as shown in FIG. 2 possible that the roll stand 1 additionally intermediate rolls 10, 11 has. In this case, the work rolls 4, 5 are supported on the support rolls 8, 9 via the intermediate rolls 10, 11. The other rollers - that is, the support rollers 8, 9 and optionally also the intermediate rollers 10, 11 - are mounted in the rolling stand uprights 3, so that they are rotatable about a respective axis of rotation.

Two of the rollers 4, 5, 8, 9, 10, 11 are mounted in the rolling stand 3 so that they are axially against each other. In the case of a Duogerüsts and also in the case of a Quartogerüsts the two axially mutually displaceable rollers are the work rolls 4, 5. The displacement thus takes place in the direction of the axis of rotation 6, 7. The displaceability is in FIG. 1 indicated by corresponding double arrows at the work rolls 4, 5. In the case of a sexto scaffold, the two axially displaceable rollers are generally the intermediate rollers 10, 11. The displaceability is in FIG. 2 indicated by corresponding double arrows in the intermediate rolls 10, 11. The work rolls 4, 5 have in this case, as a rule, a relatively small diameter and are cylindrical or (symmetrically) slightly spherical. In individual cases, however, alternatively or in addition to the intermediate rolls 10, 11, in the case of a sexto scaffolding the work rolls 4, 5 can also be axially displaceable relative to one another. In this case, the work rolls 4, 5 - optionally in addition to the intermediate rolls 10, 11 - corresponding contours.

Regardless of whether the work rolls 4, 5 or the intermediate rolls 10, 11 are axially displaceable against each other, the displacement of the corresponding rollers 4, 5 and 10, 11 is always in opposite directions. Thus, when a work roll 4, 5 or intermediate roll 10, 11 is displaced in the positive direction by a certain amount, the other work roll 5, 4 or intermediate roll 11, 10 is displaced in the negative direction by the same amount.

The two axially mutually displaceable rollers 4, 5 and 10, 11 - ie either the two work rolls 4, 5 or the two intermediate rollers 10, 11 - have according to FIG. 3 an effective bale length L on. The corresponding rollers 4, 5 and 10, 11 furthermore have, as from in FIG. 3 above or below the respective roller 4, 5 and 10, 11 given equations for the radius R1, R2 of the respective roller 4, 5 and 10, 11 can be seen, each having a curved contour, which extends over the entire effective bale length L extends. The radii R1, R2 as a function of the location x along the axes of rotation 6, 7 correspond to the contours of the rollers 4, 5 and 10, 11th

The two axially mutually displaceable rollers 4, 5 and 10, 11 have according to FIG. 3 first on a base radius R0. The base radius R0 is constant, ie no function of the location x along the axis of rotation 6 of the first work roll 4 or the location x along the axis of rotation 7 of the second work roll 5 or the axes of rotation of the intermediate rolls 10, 11. This base radius R0 is in the case of first work roll 4 (or the first work roll 4 adjacent intermediate roll 10) superimposed on a first basis function B1, in the case of the second work roll 5 (or the second work roll 5 adjacent intermediate roll 11) has a second basic function B2. The basic functions B1, B2 are according to FIG. 3 Functions of the location x in the direction of the respective axis of rotation 6, 7.

The basic functions B1, B2 are preferably, with respect to the center of the bale, antisymmetric to one another. So these are odd functions in the mathematical sense. The relation B1 (x) = -B2 (-x) holds. The basic functions B1, B2 are determined so that they complement each other in the unloaded state of the respective rollers 4, 5 and 10, 11 in a certain relative axial position of the respective rollers 4, 5 and 10, 11 complementary and at one of this axial position outgoing shift depending on the direction of displacement form a convex or a concave roll gap profile.

$$\mathrm{B}2=-\mathrm{A}\cdot \sin \left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x-c\right)\right)+B\cdot x$$

For example, for the first basic function B1 and the second basic function B2 according to FIG. 3 the relationships $$\mathrm{B}1=+\mathrm{A}\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x+c\right)\right)-B<figure-callout\; id="2"\; label="\cdot \; x\; B"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>x$$

$$\mathrm{B}$$$$\mathrm{}2=-\mathrm{A}\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x-c\right)\right)+B\cdot x$$

• x der Ort bzw. die Axialposition, bezogen auf die Ballenmitte,
• A eine Konturamplitude,
• ϕ ein Konturwinkel,
• c eine Konturverschiebung,
• L_Ref eine Referenzlänge und
• B eine Kontursteigung.

In equations 1 and 2 are

• x the location or the axial position, relative to the center of the bale,
• A is a contour amplitude,
• φ a contour angle,
• c a contour shift,
• L _ref a reference length and
• B is a contour gradient.

The meaning of these quantities is mentioned in the beginning WO 03/022 470 A1 explained. There, also possible values for the contour angle φ and a dimensioning rule for the contour gradient B are indicated. The reference length L _Ref may be identical to the ball length L. Alternatively, it can be a different value.

Obviously, the basic functions B1, B2 are determined so that they complement each other in the unloaded state of the corresponding rollers 4, 5 and 10, 11 in a certain relative axial position of the corresponding rollers 4, 5 and 10, 11 complementary. This axial position is reached when the first work roll 4 (or the first work roll 4 adjacent intermediate roll 10) is displaced in the positive direction by the contour displacement c and the second work roll 5 (or the second work roll 5 adjacent intermediate roll 11) in negative Direction is shifted by the contour shift c. If, however, starting from this axial position, a displacement of the first work roll 4 (or the first work roll 4 adjacent intermediate roll 10) in the positive direction and thus corresponding to the second work roll 5 (or the second Work roll 5 adjacent intermediate roll 11) takes place in the negative direction, the basic functions B1, B2 form a convex roll gap profile. Conversely, starting from this axial position, displacement of the first work roll 4 (or the intermediate work roll 10 adjacent to the first work roll 4) in the negative direction and, corresponding thereto, the second work roll 5 (or the intermediate work roll 11 adjacent to the second work roll 5) is positive Direction, the basic functions B1, B2 form a concave roll gap profile. Furthermore, due to the specification of the basic functions B1, B2 according to FIG. 3 the basic functions B1, B2, relative to the center of the bale, antisymmetric to each other.

The first basic function B1 is additionally superimposed on an additional function Z1. In an analogous manner, the second basic function B2 is additionally superimposed with an additional function Z2. The additional functions Z1, Z2 are according to FIG. 3 - Analogous to the basic functions B1, B2 - functions of the place x in the direction of the respective axis of rotation 6, 7th

$$\mathrm{Z}2=-\left(2-\alpha \right)\cdot {\mathit{Cx}}^2-\left(2-\beta \right)\cdot {\mathit{Dx}}^4$$

For example, for the first additional function Z1 and the second additional function Z2 according to FIG. 3 the relationships $$\mathrm{Z}1=-\alpha \cdot {\mathit{cx}}^2-\beta \cdot {\mathit{dx}}^4$$

$$\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}2=-\left(2-\alpha \right)\cdot {\mathit{cx}}^2-\left(2-\mathrm{<figure-callout\; id="4"\; label="\beta \; \cdot \; dx"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\beta \; </figure-callout>}\right)\cdot {\mathit{dx}}^{}{\mathit{}}^4$$

In equations 3 and 4, α and β are weighting factors, which typically have a value between 0 and 2. The limits 0 and 2 can be assumed with. In individual cases even larger or even smaller values can be assumed. The weighting factors α, β can be determined independently of each other. Preferably, both weighting factors α, β have the value 1. This has the advantage that the additional functions Z1, Z2 are symmetrical to one another. C and D are proportional factors. As a rule, the proportion factor C has a value above zero. The proportion factor D may be 0, greater than zero, or less than zero as needed.

If the two axially mutually displaceable rollers 4, 5 and 10, 11 are not shifted from each other (displacement s = 0), the center of the bale of both axially mutually displaceable rollers 4, 5 and 10, 11 thus in the direction of the axis of rotation 6, 7 Thus, if the sum of the additional functions Z1, Z2 is the same at the same location, the relationship applies regardless of the choice of the weighting factors α and β $$\mathrm{Z}1+\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}2=-2{\mathit{cx}}^2-2{\mathit{<figure-callout\; id="4"\; label="dx"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">dx</figure-callout>}}^4$$

The sum of the additional functions Z1, Z2 is thus, based on the center of the bale of the two axially mutually displaceable rollers 4, 5 and 10, 11, a symmetrical, mutually monotonous function.

Strictly speaking, it is only necessary that the sum of the additional functions Z1, Z2, based on the center of the bale of the two axially mutually displaceable rollers 4, 5 and 10, 11 in the unshifted state, a symmetrical, mutually monotonous function. Preferably, however, this also applies to the additional functions Z1, Z2 considered in isolation. Preferably, therefore, each of the two additional functions Z1, Z2, based on the center of the bale, a symmetrical, mutually monotonous function.

In the context of the embodiment according to FIG. 3 For example, the first basis function B1 is a trigonometric function superimposed on a linear function. The trigonometric function may in particular be a sine function. The sum of the additional functions Z1, Z2, however, is a polynomial function. The polynomial function, as seen from the center of the bale and in the direction of the respective axis of rotation 6, 7, has at least a second degree component. Preferably - namely, if the proportion factor D has a value other than 0 - the polynomial function also has a fourth degree component.

In the following, the standard case is treated according to which the two weighting factors α, β have the value 1. If the two Weighting factors α, β have a different value, resulting in principle equivalent results. It is further assumed that the two work rolls 4, 5 are the two axially mutually displaceable rolls. If the intermediate rollers 10, 11 are axially displaceable against each other, also results in principle equivalent results.

If the axes of rotation 6, 7 of the work rolls 4, 5 have a distance d from each other and the first work roll 4 is displaced by a shift s and thus correspondingly the second work roll 4 is displaced by the same value in the opposite direction, applies in the just outlined Standard case for the nip g, the work rolls 4, 5 together form the relationship $$G=d0\left(s\right)+2A\cdot \mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">cos</figure-callout>}\left(\frac{2\phi }{L_{\mathrm{Ref}}}x\right)\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{L_{\mathrm{Ref}}}\left(s-c\right)\right)+2\left(C+6{\mathit{<figure-callout\; id="2"\; label="ds"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">ds</figure-callout>}}^2\right)\cdot x^2+2D\cdot x^4$$

Here, d0 is a value which depends on the displacement s, but not on the location x in the direction of the axis of rotation 6, 7.

The resulting course of the roll gap g has on the one hand a convex or concave portion, which is dependent on the displacement s, namely the proportion $$2A\cdot \mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">cos</figure-callout>}\left(\frac{2\phi }{L_{\mathrm{Ref}}}x\right)\cdot \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">sin</figure-callout>}\left(\frac{2\phi }{L_{\mathrm{Ref}}}\left(s-c\right)\right)$$

In addition, however, the resulting course of the roll gap g has a further convex or concave portion, which is not dependent on the displacement s, namely, in the case that the proportion factor D has the value 0, the proportion $$2{\mathit{<figure-callout\; id="2"\; label="cx"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">cx</figure-callout>}}^2$$

In the case that the proportion factor D has a value other than 0, the independence of the displacement s for the 4th degree proportion holds.

FIG. 4 shows a similar embodiment as FIG. 3 , In contrast to FIG. 3 is in the embodiment according to FIG. 4 however, the first basis function B1 is a polynomial function. Furthermore, unlike FIG. 3 in the embodiment according to FIG. 4 the sum of the additional functions Z1, Z2 a trigonometric function. In particular, the trigonometric function according to FIG. 4 be a cosine function. λ is a suitably chosen factor.

The embodiments according to the 3 and FIG. 4 are combinable with one another insofar as the additional functions Z1, Z2 can be selected independently of the basis functions B1, B2. In the case that the basic functions B1, B2 are linear combinations of a trigonometric function and a linear function, the additional functions Z1, Z2 are therefore not necessarily polynomial functions. It could also be trigonometric functions, in particular trigonometric functions according to FIG. 4 , In an analogous manner, in the case that the basic functions B1, B2 are polynomial functions, the additional functions Z1, Z2 are not necessarily trigonometric functions. It could also be polynomial functions, in particular polynomial functions according to FIG. 3 ,

FIG. 5 shows purely exemplary of the embodiment according to FIG. 3 the deviation of the resulting roll gap g from an average value. Out FIG. 5 In particular, it can be seen that a very uniform profile can be achieved to a considerable extent as a result of the superimposition of the basic functions B1, B2 with the additional functions Z1, Z2. By a corresponding determination of the proportional factors C and D, the maxima 12 of the deviation can be further influenced both with regard to their position in the direction of the axis of rotation 6, 7 and with respect to their height.

As already mentioned and in FIG. 1 shown, are often in addition to the work rolls 4, 5 support rollers 8, 9 available. In this case, it is possible that the contours of the back-up rolls 8, 9 are different from those of the work rolls 4, 5 by a concave difference. This is in FIG. 6 shown, in FIG. 6 the difference is clearly exaggerated. As already mentioned and in FIG. 2 shown, in addition to the work rolls 4, 5 and the support rollers 8, 9 intermediate rollers 10, 11 may be present. In this case (exceptionally), the work rolls 4, 5 are the axially displaceable rollers, it is possible in this case that the contours of the intermediate rolls 10, 11 of those of the work rolls 4, 5 and / or the support rollers 8, 9 to distinguish a concave difference. This is in FIG. 7 shown, in FIG. 7 analogous to FIG. 6 the differences are clearly exaggerated. If, however, (in accordance with the rule in the case of a sexto scaffold), the intermediate rolls 10, 11 are the axially displaceable rolls, it is possible - analogously to the situation with a quarto scaffolding - that the contours of the support rolls 8, 9 are different from those of the intermediate rolls 10, 11 distinguish a concave difference.

The present invention has many advantages. In particular, while maintaining the advantages of rolling stands with axially displaceable rollers 4, 5 or 10, 11, in particular according to the SmartCrown technology, can be achieved that the given by the displacement of the corresponding rollers 4, 5 and 10, 11 control range Balancing effect is shifted in a desired target area. If, for example, the adjustment range achievable by shifting the work rolls 4, 5 should be between-400 μm and -100 μm in crowning, this can be achieved by setting the adjustment range between +300 μm and +600 μm using only the basis functions B1, B2 would lie, by the additional functions Z1, Z2, however, in addition a parabolic crowning of -700 microns is superimposed. The superimposition of the basic functions B1, B2 and the additional functions Z1, Z2 can be used to selectively suppress edge waves as well as center waves as well as quarter waves. The oppression is particularly effective if not only the proportion factor C, but also the proportion factor D has a value other than 0.

Although the invention has been further illustrated and described in detail by the preferred embodiment, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

LIST OF REFERENCE NUMBERS

1

rolling mill

2

rolling

3

Rolling mill stand

4, 5

strippers

6, 7

rotational axes

8, 9

backup rolls

10, 11

intermediate rolls

12

maxima

A

contour amplitude

B

contour gradient

B1, B2

basic functions

c

contour shift

C, D

proportional factors

d

Distance of rotation axes

G

nip

L

effective bale length

L _Ref

reference length

R0

base radius

R1, R2

Radii of the work rolls

s

shift

x

Place in the direction of the axis of rotation

Z1, Z2

Additional functions

α, β

Weighting factors

λ

factor

φ

contour angle

Claims (4)

1. Roll stand for producing flat rolled stock (2), in particular metal strip,

   - wherein the roll stand has roll stand uprights (3),

   - wherein work rolls (4, 5) or work rolls (4, 5) and backup rolls (8, 9) or work rolls (4, 5), intermediate rolls (10, 11) and backup rolls (8, 9) are mounted in the roll stand uprights (3),

   - wherein the rolls (4, 5, 8, 9, 10, 11) mounted in the roll stand uprights (3) are rotatable about a respective rotational axis (6, 7),

   - wherein, in the case where work rolls (4, 5) or work rolls (4, 5) and backup rolls (8, 9) are mounted in the roll stand uprights (3), the work rolls (4, 5) are displaceable with respect to one another in the direction of their respective rotational axis (6, 7), i.e. axially, and in the case where work rolls (4, 5), intermediate rolls (10, 11) and backup rolls (8, 9) are mounted in the roll stand uprights (3), the work rolls (4, 5) or the intermediate rolls (10, 11) are displaceable with respect to one another in the direction of their respective rotational axis (6, 7), i.e. axially,

   - wherein the rolls (4, 5 or 10, 11) that are axially displaceable with respect to one another have in each case an effective barrel length (L),

   - wherein the rolls (4, 5 or 10, 11) that are axially displaceable with respect to one another have in each case a curved contour (R1, R2), which extends over the entire effective barrel length (L),

   - wherein one of the two rolls (4, 5 or 10, 11) that are axially displaceable with respect to one another has a first contour (R1), which is formed by superposing a first basis function (B1) and a first additional function (Z1),

   - wherein the other of the two rolls (4, 5 or 10, 11) that are axially displaceable with respect to one another has a second contour (R2), which is formed by superposing a second basis function (B2) and a second additional function (Z2),

   - wherein the basis functions (B1, B2) satisfy the relationships $$\mathrm{B}1=+\mathrm{A}\cdot \sin \left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x+c\right)\right)-B\cdot x$$

   

   and $$\mathrm{B}2=-\mathrm{A}\cdot \sin \left(\frac{2\phi }{{\mathrm{L}}_{\mathrm{Ref}}}\left(x-c\right)\right)+B\cdot x$$

   

   or the relationships $$\mathrm{B}1=+\mathrm{A}\prime {\left(\mathrm{x}+\mathrm{c}\right)}^5+\mathrm{A}{\left(\mathrm{x}+\mathrm{c}\right)}^3-B\cdot x$$

   

   and $$\mathrm{B}2=-\mathrm{A}\prime {\left(\mathrm{x}-\mathrm{c}\right)}^5-\mathrm{A}{\left(\mathrm{x}-\mathrm{c}\right)}^3+B\cdot x$$

   

   and the additional functions (Z1, Z2) satisfy the relationships $$\mathrm{Z}1=-\alpha \cdot {\mathit{Cx}}^2-\beta \cdot {\mathit{Dx}}^4$$

   

   and $$\mathrm{Z}2=-\left(2-\alpha \right)\cdot {\mathit{Cx}}^2-\left(2-\beta \right)\cdot {\mathit{Dx}}^4$$

   

   or the relationships $$\mathrm{Z}1=-\alpha \cdot C\cos \mathit{\lambda x}$$

   

   and $$\mathrm{Z}2=-\left(2-\alpha \right)\cdot C\cos \mathit{\lambda x}$$

   

   where

   - B1 and B2 are the first and second basis functions,

   - Z1 and Z2 are the first and second additional functions,

   - A and A' are contour amplitudes,

   - ϕ is a contour angle,

   - L_Ref is a reference length,

   - x is the location or the axial position, with respect to the center of the barrel,

   - c is a contour displacement,

   - B is a contour pitch,

   - α and β are weighting factors,

   - C and D are proportional factors and

   - λ is a factor.
2. Roll stand according to Claim 1,
   characterized
   in that the additional functions (Z1, Z2) are symmetric to one another.
3. Roll stand according to Claim 1 or 2,
   characterized
   in that the work rolls (4, 5) are supported on backup rolls (8, 9) directly and in that the contours of the backup rolls (8, 9) differ from those of the work rolls (4, 5) by a concave difference.
4. Roll stand according to Claim 1 or 2,
   characterized
   in that the work rolls (4, 5) are supported on backup rolls (8, 9) by way of intermediate rolls (10, 11) and in that the contours of the intermediate rolls (10, 11) differ from those of the work rolls (4, 5) and/or of the backup rolls (8, 9) by a concave difference.

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