ROLLER LEVELER AND METHOD FOR OPERATING SAME

Abstract

The invention relates to a roller leveler (1) having a set of upper and lower flattening rollers (2), wherein each flattening roller (2) is provided with a rotary drive (3) actuated by leveler control (4) for rotating the flattening roller (2) to advance a to-be-flattened metallic flat material in a forward direction (F) and, thereby, flatten the flat, metallic material. To achieve an improved and optimal flattening result, the invention proposes that each flattening roller (2) has a first rotary drive (L.sub.1, L.sub.2 . . . L.sub.n) for driving one axial end of the flattening roller (2), and a second rotary drive (R.sub.1, R.sub.2 . . . R.sub.n) for driving one axial end of the flattening roller (2) and a second rotary drive (R.sub.1, R.sub.2 . . . R.sub.n) for driving the other end of the flattening roller, wherein the leveler controller (4) is designed to apply a parameter determining the direction of rotation of the flattening roller (2) to the first and second rotary drives (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n) individually based on a pre-set value. The invention also relates to a method of operating a roller leveler of this kind.

Claims

1. Roller leveler, comprising a set of upper and lower flattening rollers (2), wherein each flattening roller (2) is provided with a rotary drive (3) actuated by leveler control (4) for rotating the flattening roller (2) to advance a to-be-flattened metallic flat material in a forward direction (F) and, thereby, flatten the same, characterized in that each flattening roller (2) has a first rotary drive (L.sub.1, L.sub.2 . . . L.sub.n) for driving one axial end of the flattening roller (2), and a second rotary drive (R.sub.1, R.sub.2 . . . R.sub.n) for driving another axial end of the flattening roller (2), wherein, the leveler control (4) is designed to control a respective first and second drive (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n) individually to impart thereto, in accordance with a pre-set value, a parameter that determines a rotational movement of the flattening roller (2).

2. Roller leveler according to claim 1, characterized in that the leveler control (4) is connected with a set value transmitter (5) that transmits parameters of the rotational movement of the flattening rollers (2) to all of the rotary drives (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n).

3. Roller leveler according to claim 1, characterized in that the leveler control (4) is so formed that a predetermined torque (Md) is imparted to the respective first and second rotary drives (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n).

4. Roller leveler according to claim 1, characterized in that the leveler control (4/ is so formed that a predetermined rotational speed (n) is imparted to the respective first and second drives (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n).

5. Roller leveler according to claim 1, characterized in that the leveler control (4) is formed to regulate parameters determining the rotational movement of the flattening rollers (2) in a closed circuit.

6. Roller leveler according to claim 5, characterized in that the regions of the first and second drives (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n), sensors (6) for detecting of the torque (Md) and/or the rotational speed (n) are provide which communicates with the leveler control (4).

7. Method of operating a roller leveler having a set of upper and lower flattening rollers (2), wherein each flattening roller (2) is provided with a rotary drive (3) actuated by leveler control (4) for rotating the flattening roller (2) to advance a to-be-flattened metallic flat material in a forward direction (F) and, thereby, flatten the same, characterized in that each flattening roller (2) has a first rotary drive (L.sub.1, L.sub.2 . . . L.sub.n) for driving one axial end of the flattening roller (2), and a second rotary drive (R.sub.1, R.sub.2 . . . R.sub.n) for driving another axial end of the flattening roller (2), wherein, the leveler control (4) imparts to a respective first and second drive (L.sub.1, L.sub.2 . . . L.sub.n, R.sub.1, R.sub.2 . . . R.sub.n) an individual value for at least one parameter that determines a rotational movement of the flattening roller (2).

8. Method according to claim 7, characterized in that the leveler control (4) is operated alternatively in one of the following operational mode: a) Operating only the first rotary drive (L.sub.1, L.sub.2 . . . L.sub.n) of the flattening roller (2); b) Operating only the second rotary drive (R.sub.1, R.sub.2 . . . R.sub.n) of the flattening roller (2); c) Operating both the first rotary drive (L.sub.1, L.sub.2 . . . L.sub.n) and the second rotary drive (R.sub.1, R.sub.2 . . . R.sub.n) of the flattening roller (2).

9. Method according to claim 7 or 8, characterized in that a set-value transmitter (5) supplies the leveler control (4) with a pre-set value for a parameter that determines a rotational movement of the flattening roller (2).

10. Method according to claim 9, characterized in that the set-value transmitter (5) is connected with a module (7) in which a number of different flattening strategies is stored, wherein for each flattening strategy, a data set for the parameter determining rotational movement of the flattening roller (2) is available, and wherein the module (7) communicates, to the set-value transmitter (5), the data set according to a selected flattening strategy.

Description

[0039] The drawing shows an embodiment of the invention. Single FIGURE shows a schematic plan view of a roller leveler for flattening a metal strip.

[0040] The drawing schematically shows a plan view of a roller leveler 1 having a number of flattening rollers 2 of which only one set is shown. An upper set and a lower set of flattening rollers 2 are provided for flattening a metal strip, not shown. During a flattening process, the strip is advanced in a forward direction F.

[0041] Each flattening roller 2 has a drive 3 which, in the present case, consists of first and second drives arranged, respectively at two opposite axial ends of the flattening roller 2. Each flattening roller 2 thus has a drive at each axial end which is, respectively, controlled by leveler control 4. By way of example, this is illustrated for the left side of the roller leveler 1, wherein the first drives L.sub.1, L.sub.2 . . . up to L.sub.n are shown. Correspondingly, the second drives R.sub.1, R.sub.2 . . . up to R.sub.n are provided at the right side.

[0042] The leveler control 4 communicates to the flattening roller 2 their operating parameter via the respective first and second drives. In this way, a separate control applies to both axial ends of the flattening rollers, thus, to both rotary drives. In this way, the right-side control and the left-sight control of all of the flattening rollers 2 take place independently from each other.

[0043] This also applies to each separate first and second drives. To this end, the leveler control transmits relevant parameters to the drives, namely, the torque Md with which the rotary drives drive the flattening rollers 2, as well as the number of resolutions (or rotary speed). The pre-set values of the torque or the number of revolutions are retained by the leveler control 4 in a closed control circuit. To this end, sensors 6 are provided (of which only one is shown in the drawing) which determine the actual values (of the torque and the rotary speed) and transmit them to the leveler control 4, so that upon deviation from the set value, readjustment can take place.

[0044] By actuation of all of the drives, the leveler control 4 transmits further adjustment parameters to roller leveler in order to adjust the flattening gap and retain it in regulated manner at the predetermined value. This is carried out by setting the immersion depth, deflection, pivoting, the compensation system, etc. Here, however, the case is of per se known method of operation of a roller leveler and, therefore, the above-discussed control is shown in the drawing only schematically by a dash arrow.

[0045] In this regard, it should be pointed out the mutual influence of the flattening gap dimensions, material parameters, adjustment parameters, and driving parameters, so that every change is considered not in isolation but as a part of the entire regulation concept.

[0046] The leveler control 4 is connected with a set value transmitter 5 in which the concrete data for torque and rotational speed are stored. The leveler control 4, thus, converts set value input data in control data for the leveler functionality. The set value input data contain all necessary parameters and, thus, all driving parameters for adjustment of each flattening roller of the roller leveler and the flattening gap for each flattening pass.

[0047] The precise adjustment of the drive parameters (torque, rotational speed of each flattening roller 2 can be expanded by use a one-side drive or a two-side drive, which depends on a pre-determined flattening strategy. To this end, a module 7 for storage or calculation of the flattening strategy is provided and which includes the set value adjuster 5. The selection of a definite flattening strategy, thus, leads to transmitting of corresponding data from module 7 to the set value adjuster 5 and further to the leveler control 4.

[0048] In addition, the separate control of the left and right flattening rollers drives Ln,Rn provides for targeted distribution of the driving parameters, so that the drives are synchronized or are controlled or regulated with a desired trimming. In this way, specifically, influence of the flattening on to-be-flattenedproduct can be preset.

[0049] It is particularly advantageous to individually control both drives of each flattening roller in order to provide for a load balancing regulation of two adjacent flattening rollers. A targeted regulation of torque distribution has a positive effect on the service life of the drives.

[0050] The incorporation of the drive control in the regulation, i.e., adaption of the pre-set torque Md or the rotational speed n is shown on the right side of the drawing. From the drive train, sensor 6 determines the measured variable and transmits it as set/actual value comparison to the leveler control 4 that corrects the controlled deviation. This individual regulation is provided for each right-side and left-side drive. For the sake of clarity, this control circuit is limited to the drive R.sub.1 in the drawing.

[0051] The proposed roller leveler 1 may have different concepts and corresponding specific constructional detail for changing the rollers. It makes sense (but not absolutely necessary), to place the drives, at least on one side at which the roller exchange is to-be-taken place, on a common base, in a block, to simplify as much as possible the contemplated process. Exchange of all or separate rollers can be contemplated. In each case, the roller or the entire roller set should be decoupled from their drives, on both sides, and those rollers are removed from the region of the roller leveler.

[0052] For roller exchange, the drive of one side (for separate or the totality of rollers) should be removed from the roller exchange zone. To this end, the drive is pushed, dependent on space conditions of the layout of the leveler, in the direction of the roller axis or/and transverse thereto, so that the space in front of the leveler is free for removal the roller set or a separate roller and for inserting into the leveler anew roller or a roller set.

[0053] Finally, the drive is brought back in its operational position, the flattening roller are coupled to the drives, and the roller leveler is placed in its ready-for-operation position.

[0054] The proposed roller leveler can be used for flattening sheets, strips, and their cut-outs. The thickness of the material varies preferably from 1 mm to 70 mm, particularly advantageous from 1 mm to 30 mm; the maximum material thickness is about 150 mm.

[0055] The material width preferably is between 600 mm and 6000 mm, with maximum width about 700 mm.

[0056] During processing, the temperature of the material is less than 600 C. The yield strength of the material is preferably above 460 MPa, advantageously above 800 MPa.

LIST OF REFERENCE NUMERALS

[0057] 1 Roller leveler [0058] 2 Flattening roller [0059] 3 Rotary Drive [0060] 4 Leveler Control [0061] 5 Set value transmitter [0062] 6 Sensor [0063] 7 Module for storing flattening strategies [0064] L.sub.1, L.sub.2 . . . L.sub.n) first rotary drive [0065] R.sub.1, R.sub.2 . . . R.sub.n) second rotary drive [0066] F Forward direction [0067] Md Torque [0068] n Rotational speed/number of revolutions