EP2251107B1 - Method for setting the position of a roller in a rolling mill stand of a rolling mill and system comprising a rolling mill and a calibrating stand for carrying out the method - Google Patents

Description

The invention relates to a method for adjusting the position of at least one roller in a rolling mill stand of a rolling mill, wherein the rolling mill stand at least one rolling mill with a number of rolls receives, each roll is arranged in a roll position, and wherein the roll positions acting on means for adjusting the rolls are present relative to the roll stand. Furthermore, the invention relates to a system consisting of a rolling mill and a calibration stand according to the preamble of patent claim 7.

For rolling of tubes and rods rolling stands are used, in which a plurality of roller assemblies are present, each storing a roller. Several rollers are arranged around the rolling axis and comprise substantially the entire circumference of the rolling stock. The rollers together form the roller caliber. Rolling mills with such rolling stands are for example from DE 103 16 650 B3 , from the DE 10 2005 042 835 B3 , from the DE 103 07 199 B3 and from the DE 200 05 700 U1 known.

A preferred embodiment of the known rolling mills provides that the adjustment of the rolls and their rolling stands outside the machine (Roll mill stand) takes place and that then takes place after installation of the rolls including rolling stands only one roll adjustment in the machine. Each roller can be set separately in its rolling stand.

In two-roll systems, it is known to collapse, bias and thereby calibrate the system as the rolls are adjusted. From the position thus found, the defined desired nips are approached.

In three-roll systems, it is known that the stands are set outside the machine to a nominal size. The machine is calibrated by a calibrator. It is advantageous if the same calibration device is used for calibrating the machine and for calibrating the roll stand adjusting device.

The following has proven to be disadvantageous with regard to the procedure described last: The environmental conditions between the rolling stand setting device and the machine are not identical, since on the one hand the entire dimensional chains are subject to tolerances and on the other hand the conditions can constantly change. For example, wear or contamination can distort the setting of the rollers to the required (ideal) caliber. Is z. B. the rolling mill by dirt in the machine slightly higher than in the adjustment, the roll positioning is erroneous by this amount.

The result is quality losses on the finished rolled product.

The invention is therefore based on the object to provide a method of the type mentioned, with which it is possible, in a simple and fast way to an accurate adjustment of the rollers to the desired (ideal) Caliber to arrive, so that the quality of the rolled product is optimal, and to propose a corresponding system consisting of a rolling mill and a calibration, with which the process can be operated. In order to ensure the reproducibility of the roll adjustment and the roller adjustment even taking into account disturbances (wear, contamination).

1. a) Anordnung mindestens eines Walzgerüstes mit seinen Walzen in einem Kalibrierstand;
2. b) Beaufschlagen der Walzenanstellung mit einer Kraft in einer Anstellrichtung, so dass die Walze mit einer definierten Anlage gegen eine Anlagefläche des Walzgerüstes des Kalibrierstandes drückt und Vermessen des tatsächlichen Kalibers der Walze in dieser Stellung;
3. c) Bestimmung des Abweichbetrages in Anstellrichtung zwischen der Stellung gemäß Schritt und der Walzenlage zur Erzielung eines idealen Kalibers;
4. d) Einbau des Walzgerüsts samt Walze aus dem Kalibrierstand in den Walzwerkständer des Walzwerks und Beaufschlagen der Walzenanstellung mit einer Kraft in Anstellrichtung, so dass die Walze mit einer definierten Anlage gegen eine Anlagefläche des in den Walzwerkständer des Walzwerks eingebauten Walzgerüstes drückt;
5. e) Verstellen der Walzenanstellung entgegen der Anstellrichtung um den Abweichbetrag und Beginn des Walzbetriebs in dem Walzwerk mit der für das betriebsfertige Walzgerüst so gewonnenen Einstellung der Walzenanstellung und der Walze.

This object is achieved according to the invention by the method comprising the steps:

1. a) arrangement of at least one rolling stand with its rollers in a calibration stand;
2. b) applying the roller adjustment with a force in a Anstellrichtung so that the roller presses with a defined system against a contact surface of the rolling stand of the Kalibrierstandes and measuring the actual caliber of the roller in this position;
3. c) determining the deviation amount in Anstellrichtung between the position in accordance with step and the roll position to achieve an ideal caliber;
4. d) installation of the roll stand together with the roll from the calibration stand into the rolling mill stand of the rolling mill and applying the roll setting with a force in the setting direction, so that the roll presses against a contact surface of the roll stand installed in the rolling mill stand of the rolling mill with a defined abutment;
5. e) adjusting the roller adjustment against the Anstellrichtung by the deviation amount and the beginning of the rolling operation in the rolling mill with the the ready-to-roll stand so gained adjustment of the roll adjustment and the roller.

Preferably, the rollers are thereby used to produce a tube or a rod. Particularly preferably, three rollers act together to encompass the substantial circumference of the rolling stock. The rollers are advantageously free of mechanical coupling.

The caliber of the caliber according to step b) above is preferably measured optically.

The amount of force is advantageously chosen equal in the above step b) and in the above step d).

The proposed system consisting of a rolling mill and a calibration stand, wherein the rolling mill has at least one rolling mill stand for receiving rollers arranged in a roll stand, wherein the rolling stand comprises means for adjusting the rollers relative to the rolling mill stand and wherein the calibration stand for receiving at least one roll stand with its Roll adjustments and rollers is formed to carry out the method according to the invention, characterized in that the roller adjustment has at least one effective in the direction of adjustment defined system, which cooperates with a contact surface on the rolling mill stand and a contact surface on the calibration. The roller adjustment can thus be pressed against the defined system both in the calibration and after the installation of the rolling stand in the rolling mill stand of the rolling mill. The calibration stand can be a rolling mill stand of conventional construction or a supporting frame equipped with the corresponding functional elements and suitable for receiving a roll stand or the like.

The calibration stand preferably has means for acting on the roll adjustment in order to press the contact of the roll in the setting direction with a force against the contact surface on the roll stand of the calibration stand.

The calibration stand may further comprise means, preferably optical means, for measuring the actual caliber of the roll in the rolling stand of the calibration stand.

Preferably, three rollers are provided which comprise the substantial circumference of the rolling stock.

The setting method according to the invention is particularly applicable in rolling mills, in which the roll adjustment is carried out as intended outside the machine or the rolling mill and the roll adjustment within the machine. Here, preferably, each roller is individually adjustable. There is preferably no mechanical coupling of the individual rollers.

Advantageously, the proposed procedure ensures a reproducible hiring the individual rollers in the mill stand. It is carried out according to a core of the invention, a mechanical fixation of the calibration position in the rolling stand, so that this position can be approached reproducible in the rolling mill regardless of the positioning of the rolling mill both in the setting (calibration) and in the machine (rolling mill stand).

Accordingly, there is the advantage that regardless of external influences, the exact caliber setting is always ensured in the machine.

Fig. 1

schematisch einen Walzwerkständer mit darin angeordnetem Walzgerüst in Walzrichtung betrachtet, in dem mit drei Walzen ein Rohr gewalzt wird;

Fig. 2

von einem weiter nicht gezeigten Kalibrierstand einen Ausschnitt eines Walzgerüsts mit Walzenanstellung in der Ausgangsposition;

Fig. 3

den linken oberen Bereich der Darstellung gemäß Fig. 2 in vergrößerter Ansicht, wobei die Walzenanstellung gegen den Anschlag im Walzgerüst angedrückt ist;

Fig. 4

drei zusammenwirkende Walzen, in Walzrichtung betrachtet, in Kalibrierstellung; und

Fig. 5

die drei zusammenwirkenden Walzen gemäß Fig. 4, in Walzrichtung betrachtet, in zum Walzen eingestellter Position.

In the drawing, an embodiment of the invention is shown. Show it:

Fig. 1

schematically considered a rolling mill stand with rolling stand arranged therein in the rolling direction, in which a tube is rolled with three rollers;

Fig. 2

from a calibration, not further shown, a section of a roll stand with roll adjustment in the starting position;

Fig. 3

according to the upper left area of the illustration Fig. 2 in an enlarged view, wherein the roller adjustment is pressed against the stop in the rolling stand;

Fig. 4

three cooperating rollers, viewed in the rolling direction, in calibration position; and

Fig. 5

the three cooperating rolls according to Fig. 4 , as viewed in the rolling direction, in rolling set position.

In Fig. 1 is a rolling mill stand 1 of a rolling mill shown schematically having a rolling mill 5 with three Walzenanstellungen 6, 7 and 8, in each of which a roller 2, 3, 4 superimposed. The rolling mill is a continuous rolling mill, a sizing mill or a stretch reducing mill. The three rollers 2, 3, 4 comprise during rolling the essential circumference of a tube to be rolled 15. The three rollers 2, 3, 4 together form the caliber 13, which gives the rolling stock the shape of the tube 15 during rolling.

So that the tube 15 is impressed by the correct geometry of the rolls, the three rollers must be accurately positioned in a Anstellrichtung z. The ideal position of the rollers 2, 3, 4 in the adjustment direction is denoted by z ₀ . The employment of the rollers 2, 3, 4 in their Walzenanstellungen 6, 7, 8 carried by means 9, of which only one is shown schematically.

For the reproducible and accurate finding of the correct roll position z ₀ , the procedure is as follows: In Fig. 2 a roll stand 10 is shown in fragmentary form in a calibration stand into which the roll stand 10 together with the installed roll 2, 3, 4 can be inserted. As in Fig. 2 can be seen, the roller adjustment 6 (as the roller adjustments 7 and 8 alike) two systems 11, which can cooperate with corresponding contact surfaces 12 on the roll stand 10. Further, means not shown are provided, with which a force F in the registered direction can be exerted on the roller adjustment 6 to press the equipment 11 on the contact surfaces 12.

This is in Fig. 3 shown. The (calibration) position thus achieved is designated A. In this position A, the caliber 13 of the roller or the roller position z _{k is} determined during calibration, for which optical measuring systems are particularly suitable. On the basis of the measured geometrical data alone, it can easily be ascertained by what amount Δz the roller has to be retracted counter to the setting direction from the position at which the unit 11 contacts the contact surface 12, in order to achieve the ideal roller position z ₀ . This is in the FIGS. 4 and 5 clarified. In Fig. 4 the calibration position A can be seen, in which the systems 11 abut against the corresponding contact surfaces 12 of the roll stand 10, while in Fig. 5 It can be seen that the roller 2 has been withdrawn in the setting direction by a deviation amount Δz in order to achieve the ideal position z ₀ .

To transfer this ideal position in the machine, ie in the rolling mill stand 1 of in Fig. 1 shown rolling mill, the complete rolling stand 10 of the calibration stand is installed as a roll stand 5 in the rolling mill stand 1. With the means 9 for adjusting the roller, the force F is now in turn applied, in such a way that the equipment 11 of the roller stops 6, 7, 8 at corresponding contact surfaces 14 (s. Fig. 1 ) abut the rolling stand 5. These bearing surfaces 14 are executed analogously to the contact surfaces 12 of the roll stand in the calibration. From this position, the roller adjustments 6, 7, 8 together with rollers 2, 3, 4 are now retracted by the determined deviation Δz in order to achieve the ideal position of the rollers 2, 3, 4. In Fig. 1 , in which the position thus obtained is shown, it can be seen that accordingly the plants 11 have lifted off the contact surfaces 14 again.

The means 9 for adjusting the rollers in the machine can be designed as hydraulic or as electromechanical adjusting elements.

The adjustment of the rolls takes place outside the machine (of the rolling mill) in the calibration stand. The position of the rollers is preferably optically detected. A reference position 11 is approached with a defined force against the mechanical stop 12 in the calibration. In this position, the caliber is measured and recorded the deviation to the ideal caliber.

In the machine, the reference position is approached with the same force via the roller adjustment and the position measuring system is calibrated in this position. The measuring system receives the correction value previously determined in the calibration stand (deviation amount Δz) for the optimum caliber position and sets the ideal caliber.

Thus, the setting of the rolling caliber, regardless of the position of the rolling stand in the machine and errors in the displacement measuring system, is always reproducible.

LIST OF REFERENCE NUMBERS

1

Mill stand

2

roller

3

roller

4

roller

5

rolling mill

6

roll adjustment

7

roll adjustment

8th

roll adjustment

9

Means for adjusting the roller

10

Rolling stand (in the calibration stand, after installation in the rolling mill stand 5)

11

investment

12

contact surface

13

caliber

14

contact surface

15

Rolling stock (pipe)

A

calibrating

F

force

z

setting direction

z ₀

ideal roll position

z _K

Roll position during calibration

Az

Deviation in adjustment direction

Claims (9)

1. A method for setting the position (z₀) of at least one roller (2, 3, 4) in a rolling mill housing (1) of a rolling mill, wherein the rolling mill housing (1) accommodates at least one rolling stand (5) with a number of rollers (2, 3, 4), wherein each roller (2, 3, 4) is arranged in a roller adjusting mechanism (6, 7, 8), and wherein means (9) are provided for acting upon the roller adjusting mechanisms (6, 7, 8) in order to adjust the rollers (2, 3, 4) relative to the rolling stand (5),
   characterized in
   that the method features the following steps:

   a) arranging at least one rolling stand (10) with its rollers (2, 3, 4) in a calibration rig;

   b) acting upon the roller adjusting mechanism (6, 7, 8) in an adjusting direction (z) with a force (F) such that the roller (2, 3, 4) presses against an abutment face (12) of the rolling stand (10) of the calibration rig with a defined abutment (11) and measuring the actual pass (13) of the roller (2, 3, 4) in this position (A);

   c) determining the deviation value (Δz) between the position (A) according to step b) and the roller position for achieving an ideal pass (z₀) in the adjusting direction (z);

   d) installing the rolling stand including roller (2, 3, 4) from the calibration rig into the rolling mill housing (1) of the rolling mill and acting upon the roller adjusting mechanism (6, 7, 8) in an adjusting direction (z) with a force (F) such that the roller (2, 3, 4) presses against an abutment face (14) of the rolling stand (5) installed into the rolling mill housing (1) of the rolling mill with a defined abutment (11);

   e) adjusting the roller adjusting mechanism (6, 7, 8) by the deviation value (Δz) opposite to the adjusting direction (z) and commencing the rolling operation in the rolling mill with the thusly obtained setting (z₀) of the roller adjusting mechanism (6, 7, 8) and the roller (2, 3, 4) for the ready-to-use rolling stand (5).
2. The method according to Claim 1,
   characterized in
   that the rollers (2, 3, 4) are used for the production of a pipe or a rod.
3. The method according to Claim 1 or 2,
   characterized in
   that three rollers (2, 3, 4) cooperate with one another.
4. The method according to Claim 3,
   characterized in
   that the rollers (2, 3, 4) are free of a mechanical coupling.
5. The method according to one of Claims 1 to 4,
   characterized in
   that the measurement of the pass (13) according to step b) of Claim 1 is carried out in an optical fashion.
6. The method according to one of Claims 1 to 5,
   characterized in
   that the value of the force (F) according to step b) and according to step d) of Claim 1 is identical.
7. A system consisting of a rolling mill and a calibration rig, wherein the rolling mill features at least one rolling mill housing (1) for accommodating rollers (2, 3, 4) arranged in a rolling stand (5), wherein the rolling stand (5) features means (9) for adjusting the rollers (2, 3, 4) relative to the rolling mill housing (1), and wherein the calibration rig is designed for accommodating at least one rolling stand (10) with its rollers (2, 3, 4) and roller adjusting mechanisms (6, 7, 8), namely for carrying out the method according to one of Claims 1 to 6,
   characterized in
   that the roller adjusting mechanism (6, 7, 8) features at least one defined abutment (11) that is effective in the adjusting direction (z) and cooperates with an abutment face (14) on the rolling mill housing (1) and an abutment face (12) on the calibration rig.
8. The system according to Claim 7,
   characterized in
   that the calibration rig features means for acting upon the roller adjusting mechanisms (6, 7, 8) in order to press the abutment (11) of the roller adjusting mechanism (6, 7, 8) against an abutment face (12) on the rolling stand (10) of the calibration rig in the adjusting direction (z) with a force (F).
9. The system according to Claim 7 or 8,
   characterized in
   that the calibration rig furthermore features means, preferably optical means, for measuring the actual pass (13) of the roller (2, 3, 4) in the rolling stand (10) of the calibration rig.

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