Stabilization of rolled products during opening and / or closing of rolling stands

Abstract

1. A method for opening and / or closing a rolling stand (1) having two work rolls (10) forming a roll nip (S) in which a rolled product (B) transported in a conveying direction (R) is deformable, the roll nip (S) being variable in a plane perpendicular to the conveying direction (R), the method comprising: conveying the rolled product (B) through the roll nip (S) along the conveying direction (R) and opening or closing the rolling stand (1) during this conveying by correspondingly widening or reducing the roll nip (S); detecting the position of the rolled product (B) before and / or after the roll nip (S) in a direction transverse to the conveying direction (R) during the opening or closing of the rolling stand (1); and changing the roll nip adjustment of the corresponding work roll (10) depending on the detected position, so that the rolled product (B) is stabilized in a target position during the opening or closing of the rolling stand (1).

Description

[Technical field]

[0001] The present invention relates to a method for opening and / or closing a rolling stand during rolling of rolled products, in particular hot rolling.The invention further relates to a rolling stand and to an apparatus for rolling rolled products. [Background technology]

[0002] During the production of flat-rolled metal products, slabs or strips are conveyed through one or more rolling stands, each having two parallel-oriented work rolls that form a roll nip through which they move, often for the purpose of thickness reduction. For the adjustment of the roll gap, the relative position of the work rolls can be changed, for example, via a hydraulic roll-down adjustment state (Anstellung) of one or both work rolls.

[0003] In a great many process situations, the rolled product is conveyed through the open rolling stands without the working rolls exerting any deformation forces on the rolled product, and only after a certain time or a given strip length are the rolling stands closed to start or continue the actual rolling process. Thus, for example, during a cantilever roll change in a continuous casting and rolling plant or rolling line, in order to allow the roll change, first of all the roll gap of the rolling stand is opened, so that the thickness loss in this rolling stand is reduced to zero. After the roll change, the roll gap is closed.

[0004] When closing or opening the roll nip, it can occur that the rolled product does not remain stable in the desired, normally central position (lage) in the roll nip, but rather runs off to the side. Small inconsistencies in the roll roll adjustment, geometric shape and the like cause the relative increase or decrease in the roll gap across the strip width not to remain constant when the rolling stand is closed, so that lateral forces are exerted on the rolled product which induce undesirable position changes in the lateral direction, i.e. in the axial direction of the work rolls.

[0005] Nos. 5,293,321, 5,312,625 and 5,433,292 describe methods and devices for the control of unstable lateral movements of a strip under the effect of a rolling process. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] DE 34 13 424 A1 [Patent Document 2] Japanese Patent Application Publication No. 59-189012A [Patent Document 3] Japanese Patent Application Publication No. 59-85314A [Patent Document 4] DE 10 2005 051 053 A1 Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the invention is to provide an improved concept for opening and closing a rolling stand, in particular to improve the reliability of the rolling process. [Means for solving the problem]

[0008] This problem is solved by a method having the features of claim 1, by a rolling stand having the features of claim 7 and by an apparatus having the features of claim 13. Advantageous further configurations result from the dependent claims, the following illustration of the invention as well as the description of advantageous embodiments. Effect of the Invention

[0009] The method, the rolling stand and the device are used in particular in rolling mills for rolling rolled products made of metal, preferably made of steel or non-ferrous metals, which are preferably metal strips, in particular hot strips.

[0010] The method according to the invention involves the opening or closing of a rolling stand having at least two working rolls forming a rolling nip, the rolled product being transported along a conveying direction for deformation through the rolling nip. At least one of the two work rolls can be moved in a plane perpendicular to the transport direction so that not only can the roll gap be enlarged and reduced, but rather the roll adjustment of the work roll can be changed relative to the rolled product. Insofar as the rolled product is formed in strip form, the expression "roll adjustment" then means the degree of inclination of the work roll in this plane relative to the other work roll or to the strip plane.

[0011] By means of the method according to the invention, the rolled product is transported through the roll nip along the transport direction and the rolling stands are opened or closed during the transport by correspondingly widening or decreasing the roll nip. In the open state of the rolling stand, the working rolls - in contrast to the closed state - advantageously have no rolling No force acts on the rolled product, or in some cases only a small force acts on the rolled product. rolling A force is applied to the rolled product.

[0012] According to the invention, during the opening and closing of the rolling stand (opening or closing), the position of the rolled product before and / or after the roll nip in a direction transverse to the conveying direction, i.e. in the axial direction of the work rolls, is detected. Published in “"Front" and "rear" are defined relative to the direction of travel of the rolled product. Depending on the detected position, the roll-down adjustment state of the corresponding work roll is The rolled product is changed so that it is held or stabilized in a target position during the opening or closing of the rolling stand. In principle, the roll-down adjustment of both work rolls can also be changed for this purpose.

[0013] The roll gap or the geometrical shape of this roll gap is adjusted accordingly so that the rolled product does not run off to the side during the opening or closing of the roll stand, but is instead held closely to the target position. In this way, a stabilization of the opening and closing process of the roll stand is achieved in the rolled product conveyed at the same time, which improves the quality of the production and can minimize possible rejects. At the same time, a particularly efficient production is possible, since roll changes, for example in a cantilevered state, are possible during continuous production, without there being any risk of interruptions in production or quality losses due to misalignment of the rolled product in the roll nip.

[0014] It should be pointed out that the expressions "position" and "lage" are used synonymously in connection with the positioning of the rolled product in the transverse roll nip.

[0015] Advantageously, the position of the rolled product is detected contactlessly, so that no unnecessary forces act on the rolled product due to the implementation of the method and, moreover, the reliability of the corresponding detectors is increased, since these are not subject to any wear or are subject to only low wear.

[0016] The position of the rolled product is detected, for example optically, preferably using one or more cameras, radar or laser scanning. In this way, existing installations can be retrofitted in a mechanically simple and reliable manner.

[0017] For the purpose of determining the position, in the case of a strip-shaped rolled product, it is worth considering detecting one or both strip edges, which can be recognized, for example via image recognition, in the case of the use of one or more cameras, and possible deviations from the target position can thus be detected with the aid of software.

[0018] As an alternative to explicit detection of the position of the rolled product, physical parameters can be utilized, such as for example the strip tension distribution, which indirectly mimic said position of the rolled product. The strip tension distribution can be measured across the width of the metal strip before and / or after the rolling roll nip, i.e. in the axial direction of the work rolls, and can then be used to make adjustments to keep the position of the rolled product stable.

[0019] Advantageously, the roll clearance of the work rolls is changed hydraulically, so that the roll clearance adjustability is realized in a mechanically simple and reliable manner, for example two hydraulic cylinders are thus provided, which act as actuators. For this purpose, hydraulic cylinders can act directly on the respective work rolls on the right and left sides, or they can move a structural unit consisting of the work roll and the associated support roll, but the roll-down adjustment of the work rolls can also be changed in other ways, for example by means of one or more electric or linear motors.

[0020] In various embodiment variants, the above-described method can also be used in rolling mills, in particular hot rolling mills, having a plurality of rolling stands, which together form a rolling line, in particular a tandem rolling line, in which the rolled product is transported through the roll nip of the respective rolling stand along the transport direction while one or more rolling stands are opened or closed. During the opening or closing of the corresponding rolling stand, the position of the rolled product before and / or after the associated roll nip in a direction transverse to the conveying direction is detected, and Depending on the detected position, the roll-down adjustment state of the corresponding work roll is changed so that the rolled product is stabilized or held in a target position during opening or closing of the corresponding rolling stand. In this way, the opening and closing of one or more rolling stands is possible simultaneously without having to stop the production process or risking quality losses.

[0021] The above-mentioned object is achieved by a rolling stand for rolling rolled products, preferably metal strips, which rolling stand In this case, the rolling stand: At least two work rolls are provided to form a rolling nip; In the roll gap, the rolled product is deformable and can be transported in the conveying direction; the roll gap has a roll adjustment device, which includes: To change the roll-down adjustment state of at least one of the work rolls in a plane perpendicular to the conveying direction, and To open or close the rolling stands accordingly by increasing or decreasing the roll gap, and The position control device has a position control device - detecting the position of the rolled product before and / or after the roll nip in a direction transverse to the conveying direction during opening or closing, and To vary the roll-down adjustment state of the corresponding work roll depending on the detected position, so that the rolled product is stabilized or held in a target position during opening or closing of the rolling stand, It is composed of:

[0022] The features, technical effects, advantages and embodiments described for this method apply analogously to the rolling stand.

[0023] The position control device therefore advantageously comprises, for the reasons mentioned above, at least one position detector, The position detector is configured to non-contactly detect the position of the rolled product before and / or after the roll nip.

[0024] Advantageously, the position detector comprises one or more cameras, for the reasons explained above.

[0025] Advantageously, the position control device further comprises a position evaluation device in communication with the position detector and a position regulator in communication with the position evaluation device, At that time, The position evaluation device, It is configured to detect a current position of the rolled product in a direction transverse to the conveying direction from a detection value of the position detector and to transmit the current position to the position adjuster, At that time, the position adjuster - calculating a swivel value for the roll reduction adjustment device from the current position of the rolled product and - controlling this roll reduction adjustment device directly or via a position regulator of the roll reduction adjustment device in such a way that the position of the rolled product is stabilized in a target position during opening or closing of the rolling stand, It is composed of:

[0026] The position detector, the position evaluation device and the position adjustment device can be separate, mutually communicating structural units or can likewise be realized in an integrated manner. Further, the position control device may be running centrally or decentralized, as a component of an internet-based and / or cloud-based application, or in other manner, and may in some cases have access to a database. It is generally true that communication between electronic components, such as, for example, between the position control device and the screw-down adjustment device, between the position detector and the position evaluation device, and between the position evaluation device and the position adjustment device, can be carried out wirelessly or wired.

[0027] Advantageously, for the reasons explained above, the roll-down adjusting device comprises one or more, advantageously exactly two, hydraulic cylinders which act as actuators of the roll-down adjusting device.

[0028] To support the work rolls and to avoid or at least limit their deflection under load, the rolling stand advantageously has two support rolls, which are correspondingly in contact with the work rolls.

[0029] The above-mentioned object is further achieved by an apparatus for rolling a rolled product, preferably a metal strip, which has one or more rolling stands according to one or more of the above-described embodiment variants, in particular where a plurality of rolling stands are provided, said rolling stands forming a rolling line, preferably a tandem rolling line.

[0030] The features, technical effects, advantages and embodiments described with respect to the method and the rolling stand apply analogously to the rolling stand.

[0031] Further advantages and features of the invention can be seen from the following description of advantageous embodiments, in which the features described can be substituted alone or in combination with one or more of the above features, insofar as the features are not inconsistent. The following description of preferred embodiments is given in conjunction with the attached figures.

[0032] Further advantageous embodiments of the invention are explained in more detail below with the aid of the description of the figures. [Brief description of the drawings]

[0033] [Figure 1] 1 is a schematic view of a rolling stand with working rolls, support rolls and a roll-down adjustment device for varying the roll gap, the rolling stand being shown in an open state. [Diagram 2] 1 is a schematic view of a rolling stand with working rolls, support rolls and a roll-down adjustment device for varying the roll gap, the rolling stand being shown in a closed state. [Diagram 3] FIG. 1 is a schematic diagram of a rolling line having multiple rolling stands and one position control device. [Figure 4] FIG. 1 is a schematic diagram of a tandem rolling line having multiple rolling stands and multiple position control devices. [Diagram 5]FIG. 1 is a schematic diagram of a rolling stand having work rolls, support rolls and one position control device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] In the following, preferred embodiments are described on the basis of figures, in which identical, similar or identically acting elements are provided with the same reference signs and repeated descriptions of these elements are partly omitted to avoid redundancy.

[0035] FIG. 1 shows diagrammatically a rolling stand 1 for rolling a rolled product B, in particular in strip form, which is transportable in a conveying direction R (perpendicular to the drawing plane).

[0036] The rolling stand 1 is preferably designed according to this embodiment as a four-roll stand for rolling hot strip, i.e. for use in a hot-rolling flat mill, although it is also possible for this rolling stand 1 to have other configurations and / or to be configured for other uses, for example as a cold rolling stand or a construction rolling stand for metal strip.

[0037] The rolling stand 1 in this embodiment has two parallel running, facing work rolls 10 which form a roll gap S, and two associated support rolls 11 which are in contact with the work rolls 10 in order to support the work rolls 10 and to avoid or at least limit deflection of the work rolls 10 under load.

[0038] The rolling stand 1 further comprises a roll gap adjustment device 12, which is configured to move at least one or both work rolls 10, preferably the upper work roll 10, in the vertical direction, i.e. in the direction of gravity, and to vary the roll gap S. For this purpose, as can be seen from a comparison of FIGS. 1 and 2, the screw-down adjustment device 12 is capable of displacing the structural unit consisting of the work roll 10 and the associated support roll 11 .

[0039] The roll reduction adjustment device 12 is furthermore designed to adjust, in addition to the vertical position of the work roll 10 in question, the inclination of this work roll in a plane perpendicular to the conveying direction R. This can be achieved in that the roll reduction adjustment device 12 has two points of application on the work roll 10 or on the structural unit consisting of the work roll 10 and the support roll 11. Motivated by the location of the drive (not shown in the figure) for the rolls 10, 11 on the drive side DS and by the location of access for operating personnel on the operating side OS, for example for maintenance of the rolling stand 1, for changing the rolls 10, 11 and the like, in this embodiment both roll adjustment positions are referred to as "operating side roll adjustment positions" s OS , and "drive side pressure adjustment position" s DS It is called.

[0040] In this embodiment, the roll-down adjustment device 12 is equipped with two hydraulic cylinders 12a, which act as actuators of the roll-down adjustment device 12. However, the roll-down adjustment state of the work rolls 10 can also be changed in other ways, for example by using one or more linear motors and / or electric motors.

[0041] The rolling stand 1 in FIG. 1 is shown in an extended (moved apart) or open state, in which the rolling roll gap S is open and, therefore, no reduction in thickness of the rolled product B takes place. An open roll gap S may be necessary at the start of the rolling process for the infeed of the rolled product B into one or more rolling stands 1, for maintenance work, for cantilever roll changes, i.e. for roll changes during continuous production, and in other process situations. FIG. 2 shows the rolling stand 1 in a closed or narrowed (moved closer together) state, in which the work rolls 10 and the support rolls 11 are in their working position. Located In this working position, a rolling force Fw acts on the rolled product B and it is plastically deformed and reduced, in particular in thickness.

[0042] When opening and / or closing the roll nip S, it may occur that the rolled product B does not remain stable in the desired normally central position (lage) in the roll nip S, but rather runs off to the side, i.e. to the left / right side in the views of Figures 1 and 2. The cause of this may be the tilted state of the adjustable work roll 10, as shown in an exaggerated manner in FIG. OS and the driving side pressure adjustment position s DS It doesn't match.

[0043] In order to stabilise the opening and closing process of the rolling stand 1, a position control device 20 is provided, which is diagrammatically illustrated in FIGS.

[0044] The position control device 20 comprises one or more position detectors 21, which are arranged, advantageously in a contact-free manner, to detect the position of the rolled product B in front of and / or behind (seen in the conveying direction R) the roll nip S of the rolling stand 1. The position detector 21 advantageously comprises for this purpose one or more cameras 21a, which are oriented, for example, towards the strip edge of the rolled product B, provided that it is in strip form. Such a position detector 21 is shown in Fig. 3, which shows a schematic plan view of a rolling line with several rolling stands 1. The position detector 21 detects the lage or position of the rolled product B in the lateral or transverse direction, i.e. in the axial direction of the work rolls 10.

[0045] Alternatively to the use of one or more cameras 21a, the position detector 21 can detect the position of the rolled product B by using detectors based on other principles. Thus, the position of the rolled product B, and in particular the possible strip edges, can be detected, for example, via radar, laser scanning or other optical methods. Alternatively, instead of an explicit position (Lage) of the rolled product B, a parameter can be used, such as e.g. strip tension distribution, which indirectly mimics the position (Lage) of the rolled product B. The strip tension distribution can be measured across the width of the rolled product B, i.e. in the axial direction of the work rolls 10, before and / or after the rolling stand 1 and used for adjustments.

[0046] The position detector 21 is in communication with a position evaluation device 22, which determines from the detection values ​​of the position detector 21 the current position x ACT and transmitting the signal to the position adjuster 23.

[0047] The position adjuster 23 adjusts the current position x of the rolled product B. ACT From this, a rotation value (differential roll reduction adjustment value) for the roll reduction adjustment device 12 of the work roll 10 is calculated. When the work roll 10 is rotated by the roll reduction adjustment device 12, the rolled product B can move sideways. The position adjuster 23 controls the corresponding roll gap adjuster 12 directly or via a position adjuster 13 (see Figures 4 and 5) of this roll gap adjuster 12, in such a way that the rolled product position is stabilized during the closure of the roll gap S. In other words, the roll gap S is closed in such a way that the position of the rolled product B remains as close as possible to the target position. For this purpose, the position adjuster 23 is in wired or wireless communication with the pressure reduction adjustment device 12 .

[0048] The position detector 21, the position evaluation device 22 and the position adjuster 23 can be separate, mutually communicating structural units or can likewise be realised in an integrated manner. Furthermore, the position control device 20 can be implemented centrally or decentrally, as a component of an internet-based and / or cloud-based application or in other ways, and possibly has access to a database. It is generally stated that communication between electronic components, such as between the position control device 20 and the screw-down adjustment device 12, between the position detector 21 and the position evaluation device 22, and between the position evaluation device 22 and the position adjustment device 23, can be performed wirelessly or wired.

[0049] FIG. 4 shows a tandem rolling line 100 having a number of rolling stands 1, whereby a number of position control devices 20 are assigned to and attached to the different rolling stands 1.

[0050] 5 shows diagrammatically a rolling stand 1 with a position control device 20 according to yet another embodiment. The position adjuster 13 of the roll clearance adjustment device 12 is divided here into a position adjuster 13a of the operating side OS and a position adjuster 13b of the drive side DS, which are designed for adjusting the position of the corresponding side, preferably the corresponding hydraulic cylinder 12a.

[0051] FIG. 5 further shows the influence of the position adjustment of the rolled product B on the position adjustment of the roll-down adjustment device 12, where F COS By this, the pressure adjustment force on the operating side OS and F CDS The pressure adjustment force on the driving side DS is displayed by s REF means the target value of the center roll-down adjustment position, Δs REF means the target value (rotation value) of the differential roll-down adjustment position, x REF denotes the target value of the rolled product position, and x OP means an additional setpoint value for the rolled product position, which is determined, for example, by a higher-level system control or by an operating personnel. At that time, the central pressure adjustment position s = (s DS -s OS ) / 2, and the differential pressure reduction adjustment position Δs=s DS -s OS holds true.

[0052] The control of the rolled product position described in this specification makes it possible to stabilise the opening and closing process of the rolling stand 1 throughout the transport of the rolled product B, since the position (posture) of the rolled product B in the lateral direction, i.e. transverse to the conveying direction R, is kept close to a target value. In this way the quality of the production can be improved and possible rejects can be minimized. Since the position control device 20 is installed in several rolling stands 1 of one rolling line, furthermore opening and closing of one or several rolling stands 1 is possible simultaneously.

[0053] To the extent possible, all individual features shown in the examples can be combined with one another and / or substituted without departing from the scope of the invention. In addition, the present application relates to the invention described in the claims, but may also include the following as other aspects. 1. A method for opening and / or closing a rolling stand (1) having two working rolls (10) forming a rolling nip (S), in which a rolled product (B) transported in the rolling nip (S) in a conveying direction (R) is deformable, comprising: The roll-down adjustment state of at least one work roll (10) is variable in a plane perpendicular to the conveying direction (R), and the method comprises: Transporting the rolled product (B) through the roll gap (S) along the transport direction (R), and opening or closing of the rolling stand (1) during its transport, with the roll gap (S) being correspondingly enlarged or reduced; Detection of the position of the rolled product (B) in a direction transverse to the conveying direction (R) before and / or after the roll nip (S) during the opening or closing of the rolling stand (1); and - changing the roll-down adjustment state of the corresponding work roll (10) depending on the detected position, so that the rolled product (B) is stabilized in a target position during the opening or closing of the rolling stand (1); 2. A method comprising: 2. The method according to claim 1, wherein the position of the rolled product (B) is detected non-contact. 3. The method according to claim 2, characterized in that the position of the rolled product (B) is detected optically, advantageously using one or more cameras (21a), radar or laser scanning. 4. The method according to claim 1, characterized in that the rolled product (B) is a metal strip and the position of the rolled product (B) is indirectly inferred from the strip tension distribution across the width of the metal strip before and / or after the rolling roll nip (S). 5. The method according to any one of claims 1 to 4, characterized in that the roll reduction adjustment state of the work roll (10) is changed hydraulically. 6. A plurality of rolling stands (1) in one rolling line are The rolling device includes two work rolls (10) each forming a rolling nip (S) in which the rolled product (B) transported in the conveying direction (R) is deformable, The adjustment of the at least one work roll (10) is variable for each rolling stand (1) in a plane perpendicular to the conveying direction (R), and the method comprises: conveying the rolled product (B) through the roll gap (S) of each of the rolling stands (1) along the conveying direction (R), and opening or closing of one or more of the rolling stands (1) during its transport, with the associated roll gap (S) being correspondingly enlarged or reduced; During the opening or closing of the corresponding rolling stand (1), Determination of the position of the rolled product (B) in a direction transverse to the conveying direction (R) before and / or after the associated roll nip (S); and - changing the roll-down adjustment state of the corresponding work roll (10) as a function of the detected position, so that the rolled product (B) is stabilized in a target position during the opening or closing of the corresponding rolling stand (1); 6. The method according to any one of claims 1 to 5, further comprising: 7. A rolling stand (1) for rolling a rolled product (B), advantageously a metal strip, said rolling stand (1) comprising: The rolling mill has two work rolls (10) forming a rolling roll gap (S), in which the rolled product (B) transportable in a conveying direction (R) is deformable; and has a roll reduction adjustment device (12), which To vary the roll-down adjustment of at least one of the work rolls (10) in a plane perpendicular to the conveying direction (R) and to open or close the rolling stand (1) accordingly by increasing or decreasing the roll gap (S), and A position control device (20) is provided, To detect the position of the rolled product (B) before and / or after the roll nip (S) during opening or closing in a direction transverse to the conveying direction (R), and to vary the roll-down adjustment of the corresponding work rolls (10) depending on the detected position in such a way that the rolled product (B) is stabilized in a target position during the opening or closing of the rolling stand (1), It is composed of A rolling stand (1). 8. The position control device (20) includes at least one position detector (21); 8. The rolling stand (1) according to claim 7, characterized in that the position detector is configured for non-contact detection of the position of the rolled product (B) before and / or after the rolling roll nip (S). 9. The rolling stand (1) according to claim 8, characterized in that the position detector (21) comprises one or more cameras (21a). 10. The position control device (20) comprises a position evaluation device (22) in communication with the position detector (21) and a position adjuster (23) in communication with the position evaluation device (22); The position evaluation device (22), From the detection value of the position detector (21), the current position (x ACT ) and to transmit it to the position adjuster (23), The position adjuster (23) The current position (x ACT ) to calculate a swivel value for the roll reduction adjustment device (12) from the roll reduction adjustment device (12) and to control the roll reduction adjustment device directly or via a position regulator (13) of the roll reduction adjustment device (12) in such a way that the position of the rolled product is stabilized in a target position during the opening or closing of the rolling stand (1), It is composed of 10. A rolling stand (1) according to any one of claims 7 to 9. 11. A rolling stand (1) according to any one of claims 7 to 10, characterized in that the roll reduction adjustment device (12) comprises one or more, advantageously exactly two hydraulic cylinders (12a). 12. A rolling stand (1) according to any one of claims 7 to 11, characterized in that the rolling stand (1) has two support rolls (11), which are correspondingly in contact with the work roll (10). 13. Apparatus (1) for rolling a rolled product (B), advantageously a metal strip, characterized in that it comprises one or more rolling stands according to any one of 7 to 12 above. 14. Apparatus (1) according to claim 13, characterized in that a plurality of rolling stands (1) are provided, said rolling stands forming a rolling line, advantageously a tandem rolling line (100). [Explanation of symbols]

[0054] 1 Rolling stand 10 Work Rolls 11 Support roll 12 Pressure adjustment device 12a Hydraulic Cylinder 13 Position adjuster for pressure reduction adjustment device 13a Position adjuster on the operating side 13b Drive side position adjuster 20 Position control device 21 Position detector (Lagedetektor) 22 Position evaluation device (Lageauswertung) 23 Position adjuster (Lageregler) 100 Tandem Rolling Line R Conveying direction B. Rolled products S Roll gap OS operation side DS Drive side F W Rolling force s OS Adjustment position for pressure reduction on the operating side s DS Drive side pressure adjustment position x ACT Current location of rolled products F COS Pressure adjustment force on the operating side F CDS Drive side pressure adjustment force s REF Target value for center pressure adjustment position Δs REF Target value of differential reduction adjustment position x REF Target value for rolled product position (Walzproduktlage) x OP Additional target value s Center pressure adjustment position Δs Differential pressure reduction adjustment position

Claims

1. 1. A method for opening and / or closing a rolling stand (1) having two work rolls (10) forming a rolling nip (S), in which a rolled product (B) transported in the rolling nip (S) in a conveying direction (R) is deformable, comprising: The roll-down adjustment state of at least one work roll (10) is variable in the gravity direction, and the method comprises: Transporting the rolled product (B) through the rolling roll gap (S) along the transport direction (R), and opening or closing of the rolling stand (1) during its transport, with the roll gap (S) being correspondingly enlarged or reduced; Detection of the position of the rolled product (B) in the strip width direction before and / or after the roll nip (S) during opening and closing of the rolling stand (1); and - changing the roll-down adjustment state of the corresponding work rolls (10) depending on the detected position, so that the rolled product (B) is stabilized in a target position during opening and closing of the rolling stand (1); In the open state of the rolling stand (1), the working rolls (10) do not exert any rolling force on the rolled product (B) in contrast to the closed state, or exert only a small rolling force on the rolled product (B); 2. A method comprising:

2. 2. The method of claim 1, wherein the position of the rolled product (B) is sensed non-contactingly.

3. 3. The method according to claim 2, characterized in that the position of the rolled product (B) is detected optically, using one or more cameras (21a), radar or laser scanning.

4. 2. The method according to claim 1, characterized in that the rolled product (B) is a metal strip and the position of this rolled product (B) is indirectly deduced from the strip tension distribution over the width of this metal strip before and / or after the rolling nip (S).

5. 5. The method according to claim 1, wherein the roll reduction adjustment of the work rolls (10) is changed hydraulically.

6. A plurality of rolling stands (1) in one rolling line, The rolling device includes two work rolls (10) each forming a rolling nip (S) in which the rolled product (B) transported in the conveying direction (R) is deformable, The roll-down adjustment state of at least one work roll (10) is variable in the gravity direction for each rolling stand (1), and the method comprises: conveying the rolled product (B) through the roll gap (S) of each of the rolling stands (1) along the conveying direction (R), and opening or closing of one or more of the rolling stands (1) during the transport thereof, with the associated roll gap (S) being correspondingly enlarged or reduced; During the opening and closing of the corresponding rolling stands (1), Determining the position of the rolled product (B) in the strip width direction before and / or after the associated roll nip (S); and - changing the roll-down adjustment state of the corresponding work roll (10) as a function of the detected position, so that the rolled product (B) is stabilized in a target position during opening and closing of the corresponding rolling stand (1); and In the open state of the rolling stand (1), the working rolls (10) do not exert any rolling force on the rolled product (B) in contrast to the closed state, or exert only a small rolling force on the rolled product (B); 6. The method according to claim 1, further comprising:

7. A rolling stand (1) for rolling a rolled product (B) or a metal strip, said rolling stand (1) comprising: The rolling mill has two work rolls (10) forming a rolling roll gap (S), in which the rolled product (B) transportable in the conveying direction (R) is deformable; and has a roll reduction adjustment device (12), which includes: To vary the roll-down adjustment of at least one of the work rolls (10) in the direction of gravity and to open or close the rolling stand (1) accordingly by increasing or decreasing the roll gap (S), and A position control device (20) is provided, to detect the position of the rolled product (B) in the strip width direction before and / or after the rolling nip (S) during opening and closing, and to vary the roll-down adjustment state of the corresponding work rolls (10) depending on the detected position, in such a way that the rolled product (B) is stabilized in a target position during the opening and closing of the rolling stand (1); It is composed of In the open state of the rolling stand (1), the working rolls (10) do not exert any rolling force on the rolled product (B) in contrast to the closed state, or exert only a small rolling force on the rolled product (B); A rolling stand (1) characterized in that

8. The position control device (20) includes at least one position detector (21); 8. The rolling stand (1) according to claim 7, characterized in that the position detector is configured for contactlessly detecting the position of the rolled product (B) before and / or after the rolling nip (S).

9. 9. Rolling stand (1) according to claim 8, characterized in that the position detector (21) comprises one or more cameras (21a).

10. the position control device (20) comprises a position evaluation device (22) in communication with the position detector (21) and a position adjuster (23) in communication with the position evaluation device (22); The position evaluation device (22) From the detection value of the position detector (21), the current position (x ＡＣＴ ) and for transmitting it to said position adjuster (23), The position adjuster (23) The current position (x ＡＣＴ ) to obtain a target value (Δs) of the differential roll-down adjustment position (Δs) for the roll-down adjustment device (12). ＲＥＦ） and for controlling said roll reduction adjusting device, either directly or via a position regulator (13) of said roll reduction adjusting device (12), in such a way that said position of said rolled product is stabilized in a target position during opening and closing of said rolling stand (1), It is composed of Differential roll-down adjustment position (Δs) = operation side roll-down adjustment position (s ＤＳ )-Drive side pressure adjustment position (s ＯＳ ) 9. The rolling stand (1) according to claim 8, characterized in that

11. 11. Rolling stand (1) according to any one of claims 7 to 10, characterized in that the roll-down adjustment device (12) comprises one or more or exactly two hydraulic cylinders (12a).

12. 12. The rolling stand (1) according to any one of claims 7 to 11, characterized in that the rolling stand (1) has two support rolls (11), which are correspondingly in contact with the work roll (10).

13. Apparatus (1) for rolling a rolled product (B) or a metal strip, characterized in that it comprises one or more rolling stands according to any one of claims 7 to 12.

14. 14. Apparatus (1) according to claim 13, characterized in that a number of rolling stands (1) are provided, said rolling stands forming a rolling line, i.e. a tandem rolling line (100).

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