EP3453466A1 - Rolling mill for rolling a metallic product and method for operating a rolling mill - Google Patents

Abstract

The invention relates to a rolling train for rolling a metallic material, comprising a cooling device (1) for cooling the rolls (2) of a rolling stand and / or the rolled or rolled material. In order to be able to easily adapt the cooling to desired cooling conditions, the invention provides that the cooling device (1) comprises at least one support frame (3) for at least one cooling element (4 ', 4 "), wherein at least two cooling elements ( 4 ', 4 ") of different design are available or are present, wherein the support frame (3) is equipped with at least one receiving element (5) which is adapted to alternatively receive a cooling element (4', 4") of a selected type Furthermore, the invention relates to a method for operating a rolling train with such a cooling device.

Description

The invention relates to a rolling train for rolling a metallic material, comprising a cooling device for cooling the rolls of a rolling stand and / or the rolled or rolled Guts. Furthermore, the invention relates to a method for operating a rolling train with such a cooling device.

In the operation of rolling mills, typically the work rolls are cooled during the rolling operation. For this purpose, various types of roll cooling devices are available in the prior art (for example, spray cooling, shell cooling, high turbulent cooling, water cooling roll cooling, ultrahigh pressure cooling and roll cooling with laminar tubes). It is always provided that a cooling concept for the cooling of the rollers selected and this is then implemented in a rolling mill.

Rebuilding a roll cooling system is rarely encountered and in any case involves a relatively high outlay and possibly also a risk; Furthermore, a conversion time is required for such a conversion, during which the plant is not available and thus causes a loss of production. This is especially true if the cooling principle is fundamentally changed, so if, for example, a change from high pressure to low pressure or another constructive solution to be used.

As a roll cooling device is often used a spray cooling, in which emerges from one or more manifolds, a plurality of water jets under a pressure of about 5 to 25 bar from nozzles. The water jets hit at different angles in the radial direction on the work roll and cool it. For this purpose, for example, on the DE 101 31 369 A1 Referenced.

In order to increase the cooling efficiency or to operate the roller cooling with lower water pressure and thus lower energy consumption, shell cooling are known, as for example in the EP 2 846 940 B1 are described. Here, water or other cooling medium between the work roll and a shell in a relatively narrow gap on the work roll along and so the work roll efficiently and usually cooled at low operating pressure.

The invention has the object of providing a generic rolling train so that it is possible in a simple manner to be able to make an adjustment of the cooling to different desired cooling conditions. Furthermore, a corresponding method should be proposed for this purpose. In particular, the disadvantages described above in the changeover from one cooling concept to another should be avoided.

The solution of this object by the invention is characterized in that the cooling device comprises at least one support frame for at least one cooling element, wherein at least two cooling elements of different types are available or are available, wherein the support frame is equipped with at least one receiving element, which is formed to record alternatively a cooling element of a selected type.

The cooling element of one type can be a spray bar for spraying cooling medium onto the roll and / or onto the material to be rolled. The cooling element of a (different) type may be at least one cooling nozzle with a cooling shell for applying cooling medium to the roll.

Other alternative cooling elements of a particular type may be high turbulent cooling, water cooled roll cooling, ultra high pressure cooling or roll cooling with laminar tubes.

It is particularly preferably provided that the receiving element of the support frame has a mechanical interface, which is designed for mechanical connection with an adapter which is arranged on the cooling element, wherein the adapter of all cooling elements are designed to match the mechanical interface of the receiving element.

The receiving element of the support frame may further comprise a fluidic interface, which is designed for fluidic connection to the cooling element.

In the support frame, at least one supply line for cooling medium is preferably arranged, wherein the supply line has means for adjusting the pressure of the cooling medium and / or the cooling medium volume flow. Thus, in a simple manner, a process-technically optimal adaptation of a selected cooling concept can take place, in which the pressure of the cooling medium or its volume flow is optimally adjusted.

1. a) Betreiben der Walzstraße unter Verwendung mindestens eines Kühlelements einer ersten Bauart, wobei über das Kühlelement Kühlmedium mit einem ersten Druckniveau und/oder mit einem ersten Volumenstrom ausgebracht wird;
2. b) Demontage des mindestens einen Kühlelements der ersten Bauart;
3. c) Montage mindestens eines Kühlelements einer zweiten Bauart;
4. d) Betreiben der Walzstraße unter Verwendung mindestens eines Kühlelements der zweiten Bauart, wobei über das Kühlelement Kühlmedium mit einem zweiten Druckniveau und/oder mit einem zweiten Volumenstrom ausgebracht wird, der sich vom ersten Druckniveau und/oder vom ersten Volumenstrom unterscheidet.

The proposed method for operating a rolling mill with a cooling device of the above type comprises the steps:

1. a) operating the rolling train using at least one cooling element of a first type, wherein via the cooling element cooling medium with a first pressure level and / or with a first volume flow is applied;
2. b) disassembly of the at least one cooling element of the first type;
3. c) mounting at least one cooling element of a second type;
4. d) operating the rolling train using at least one cooling element of the second type, wherein via the cooling element cooling medium with a second pressure level and / or with a second volume flow is applied, which differs from the first pressure level and / or the first volume flow.

It is preferably provided that a first cooling element with a supply pressure between 3 bar and 30 bar, preferably between 7 bar and 15 bar, operated and that a second cooling element with a supply pressure of less than 6 bar, preferably with a supply pressure between 1 bar and 5 bar, is operated.

A second cooling element can be operated via a pressure reducing element of a high-pressure medium supply (in this case, no conversion of the media supply from high pressure to low pressure is required). However, it can also be provided that, after a corresponding conversion of the media supply without a pressure reduction stage, said cooling element is operated by a low-pressure medium supply.

According to the above proposal, an improvement and optimization of the work roll cooling by the said conversion concept for a conversion of the cooling is thus possible.

In order to allow a smooth and risk-free conversion or to minimize the conversion time and thus the production loss of the rolling mill, the said device and the described method is proposed, which allows a simple change of work roll cooling methods or devices. As a result, the mechanical conversion effort can be kept small and a simple decommissioning or an alternative operation at least two different roll cooling devices are performed. This also makes it possible in particular to be able to test different cooling systems in a simple manner, before the one selected which has proved to be best for the specific application.

For a rebuild of a roll cooling, it makes sense to proceed in steps to minimize the risk. Furthermore, the user would like to be able to restore the roll cooling in a simple manner in case of problems. These requirements are met by the proposed solution in a very advantageous manner.

Fig. 1

schematisch eine Kühlvorrichtung zum Kühlen der Arbeitswalzen eines Walzgerüst, wobei ein Kühlelement einer ersten Bauart in Form eines Sprühbalkens eingesetzt wird,

Fig. 2

schematisch die Kühlvorrichtung gemäß Figur 1, wobei nunmehr ein Kühlelement einer zweiten Bauart in Form von Kühldüsen mit einer Kühlschale zum Aufbringen von Kühlmedium auf die Walze eingesetzt wird,

Fig. 3

schematisch die Versorgung der Kühlvorrichtung mit Kühlmedium bei einer Betriebsweise gemäß Figur 1,

Fig. 4

schematisch die Versorgung der Kühlvorrichtung mit Kühlmedium bei einer Betriebsweise gemäß Figur 2 und

Fig. 5

schematisch eine Variation der Lösung gemäß Figur 4.

In the drawings, embodiments of the invention are shown. Show it:

Fig. 1

schematically a cooling device for cooling the work rolls of a roll stand, wherein a cooling element of a first type is used in the form of a spray bar,

Fig. 2

schematically the cooling device according to FIG. 1 in which now a cooling element of a second type is used in the form of cooling nozzles with a cooling shell for applying cooling medium to the roll,

Fig. 3

schematically the supply of the cooling device with cooling medium in a mode of operation according to FIG. 1 .

Fig. 4

schematically the supply of the cooling device with cooling medium in a mode of operation according to FIG. 2 and

Fig. 5

schematically a variation of the solution according to FIG. 4 ,

In FIG. 1 and FIG. 2 is a cooling device 1 can be seen, with which the work rolls 2 of a roll stand are cooled. The cooling device 1 has a support frame 3, in each of which two cooling elements 4 'and 4 "of a certain type are mounted, namely one for cooling the upper work roll 2 and one for cooling the lower work roll 2. The support frame 3 is in the embodiment in one piece Of course, the support framework can alternatively be formed as a multi-part structure (especially since, as a rule, upper and lower cooling elements are provided).

In FIG. 1 In this case, a cooling element 4 'of a first type is used, namely in the form of a spray bar. In FIG. 2 a cooling element 4 "of a second, different from the first type design is used, namely in the form of cooling nozzles with a cooling shell for applying cooling medium to the roller. 2

The support frame 3 is equipped with receiving elements 5 (an upper for the upper cooling element and a lower one for the lower cooling element). The receiving elements 5 are designed such that they can alternatively receive a cooling element 4 'or 4 ", ie alternatively either a cooling element of a first type or of a second type The receiving elements 5 could also be used as mechanical supports for a respective cooling element 4 ', 4 "denote.

At all cooling elements 4 ', 4 "adapter 7 are arranged, which serves for the mechanical fixing of the cooling element 4', 4" on the receiving element 5.

The concept envisages that the receiving element 5 and the adapter 7 define a mechanical interface 6, which is executed in a standardized manner in such a way that optionally different cooling elements 4 ', 4 "can be mechanically fastened to the day frame 3 via the receiving element 5.

In an analogous manner, there is also a fluidic interface 8, via which a cooling element 4 ', 4 "can be supplied with cooling medium, here too a standard or normalized connection exists, so that replacement of the cooling elements 4', 4" is possible without problems ,

In the FIGS. 1 and 2 is illustrated with the dimensions a, b and c for the upper mechanical interface 6 and the dimensions X, Y and Z for the lower mechanical interface 6 that quasi a precise and easy positioning of a cooling element 4 ', 4 "on the receiving element 5 possible The same applies to the connection of a cooling element 4 ', 4 "to the fluidic interface 8, although in this case no corresponding dimensions are entered in the figures.

The slight adaptation of the respective mounted cooling elements 4 ', 4 "to a process technology optimal cooling media supply is in the FIGS. 3 to 5 illustrates where a supply line 9 for cooling medium can be seen, with which the cooling elements 4 'and 4 "are supplied with this., Provided here are means 10 and 10' for adjusting the pressure or the volume flow of the cooling medium Considering that different types of cooling elements also require different pressures or flow rates in order to work efficiently and economically.

In the first roll cooling device accordingly FIG. 1 So it is a cooling system in the form of spray bars, which carry a plurality of spray nozzles, from which a cooling medium is sprayed against the work roll 2 (spray cooling). As a second, alternative roll cooling device is according to FIG. 2 a cooling element in the form of cooling nozzles provided with cooling shells, in which the same cooling medium along the circumference of the work roll 2 is guided against the direction of rotation of the work roll (shell cooling). A possible actuating mechanism for pivoting the shell cooling unit is in for simplicity FIG. 2 not shown.

For advantageous conversion of the work roll cooling systems, the different work roll cooling devices for the upper and / or lower roll are designed so that they can either be accommodated or fastened alternatively in the support frame (support frame 3).

Thus, for example, a spray cooling installed in this support frame (support frame 3) or - alternatively - in the same support frame a shell cooling for the cooling of the top and / or bottom roll are attached. The support frame is advantageously designed so that attachment points (receiving elements 5) are provided, which can optionally accommodate both roll cooling devices.

The attachment points for the two different roll cooling devices may be provided at the same position of the support frame (as indicated by the dimensions a, b, c and X, Y and Z, respectively) or at different positions.

During a change or conversion from a first to the second roll cooling device so remain the support frame 3 and the scrapers 11, 12 and also the Verfahrzylinder 13 for the support frame 3 (support frame) functionally or structurally unchanged. Different links or adapter members may be used between the different cooling devices and the support frame. With hose connections, the two roll cooling systems are connected to the media supply in order to adapt to different cooling beam geometries and feed angles and to be able to compensate for a displacement of the support frame together with the respectively installed roll cooling devices.

In the FIGS. 1 or 2 are still the cooling medium supply 14, the fastening screws 15, the lifting point cylinder / support frame 16, the roadway 17th for the support frame 3, the spray nozzles 18, the cooling shell 19, the nozzle 20, the joint 21 for the cooling shell, the articulation lever 22 and the joint 23 for the linkage marked, both the rolling direction W.

FIG. 3 and FIG. 4 show a high-pressure medium supply 24, FIG. 5 a low-pressure media supply 25. In the case of FIG. 3 is a roller cooling device with spray cooling, while in the case of FIGS. 4 and 5 a roll cooling device is present with shell cooling.

According to FIG. 3 the high operating pressure is controlled by the means 10 in the form of a control or on / off valve. In the solution according to FIG. 4 For example, a low operating pressure, which results via the means 10 in the form of the regulating or on / off valve 10, is set via a pressure reducing stage 10 '. According to FIG. 5 However, a low operating pressure can also be set directly via the means 10 in the form of a regulating or on / off valve, since a low-pressure medium supply 25 is present here.

The first roll cooling device according to FIG. 1 The cooling element 4 'is operated with a supply pressure of between 3 and 30 bar and the second roll cooling with the cooling element 4 "with a supply pressure of less than 6 bar FIG. 1 in a supply pressure range of 7 to 15 bar (high pressure media supply 24) and the second roll cooling device according to FIG. 2 in a supply pressure range of 1 to 5 bar (low pressure media supply 25).

Furthermore, the amount of water used according to the second roll cooling device FIG. 2 (ie in the shell cooling) less than or equal to the amount of water of the first roll cooling device according to FIG. 1 (Spray-cooling). Advantageously, the second roll cooling device 4 "can optionally be operated directly with a low-pressure medium supply 25 via a pressure reduction 10 'with a high-pressure medium supply 24 or without a pressure reduction stage.

The pressure reduction can be carried out in the form of a throttle valve, a pressure regulating or -begrenzungsventils or by other process valves for pressure change from a higher medium pressure supply to the lower operating pressure. The pressure reduction can be performed with an additional pressure reduction stage or, for example, only with an existing control valve (see the FIGS. 3 to 5 ).

The support frame can be designed to be displaceable in the horizontal direction together with the respective installed cooling devices, so that the various roll cooling devices with support frame 3 can be moved back and forth from the roller as required.

1. a) Betreiben der Walzanlage mit Einsatz der ersten Walzenkühleinrichtung gemäß Figur 1, die im Traggerüst 3 befestigt ist und deren Medienversorgung mit einem ersten Betriebsdruckniveau (oberhalb des Druckniveaus der zweiten Walzenkühleinrichtung) betrieben wird;
2. b) Demontage der ersten Walzenkühleinrichtung, d. h. des Kühlelements 4';
3. c) Einbau der zweiten Walzenkühleinrichtung, d. h. des Kühlelements 4" in demselben Traggerüst 3, die mit derselben Medienversorgung mit einem zweiten Betriebsdruckniveau (unterhalb des Betriebsdruckniveaus der ersten Walzenkühleinrichtung betrieben wird) und bei der eine Druckverminderung zur Anpassung an die Medienversorgung von dem ersten Betriebsdruckniveau an das zweite Betriebsdruckniveau durchgeführt wird;
4. d) Optimieren oder Testen und/oder Betreiben der Walzstraße mit der zweiten Walzenkühleinrichtung mit der Medienversorgung entsprechend dem Schritt c);
5. e) Anpassen der Medienversorgung vom ersten hohen Versorgungsdruckniveau an das zweite niedrigere Versorgungsdruckniveau (d. h. Umbau der Medienversorgung oder Änderung der Einstellungen);
6. f) Ausbau der Druckreduzierstufe oder Veränderung der Druckreduzierung und Betreiben (ohne Druckverminderung) der zweiten Walzenkühleinrichtung mit einem niedrigen Betriebs- und Versorgungsdruckniveau entsprechend Schritt e).

The conversion steps from the use of the first roll cooling device with the cooling element 4 'to the use of the second roll cooling device with the cooling element 4 "can be carried out as follows:

1. a) operating the rolling mill with the use of the first roll cooling device according to FIG. 1 which is fixed in the support frame 3 and whose medium supply is operated at a first operating pressure level (above the pressure level of the second roll cooling device);
2. b) disassembly of the first roll cooling device, ie the cooling element 4 ';
3. c) installation of the second roll cooling device, ie the cooling element 4 "in the same support frame 3, which is operated with the same media supply at a second operating pressure level (below the operating pressure level of the first roll cooling device) and at a pressure reduction to adapt to the media supply from the first operating pressure level to the second operating pressure level is performed;
4. d) optimizing or testing and / or operating the rolling train with the second roll cooling device with the media supply according to step c);
5. e) adjusting the media supply from the first high supply pressure level to the second lower supply pressure level (ie, changing the media supply or changing the settings);
6. f) removal of the pressure reduction stage or change of the pressure reduction and operation (without pressure reduction) of the second roll cooling device with a low operating and supply pressure level according to step e).

With regard to the possible conversion conditions concerning the media supply for the various roll cooling devices (cooling elements 4 'or 4 ") is on FIGS. 3 to 5 Referenced.

If you want to change the roll cooling device again, the rebuilt roll cooling device (step c) can be very easily rebuilt at a later time in the initial state and operated according to step a).

In the conversion from a first roll cooling device into a second roll cooling device, only the upper or only the lower roll cooling or both sides can be changed.

The compatibility of the various devices and the easy interchangeability of the units in the same support frame allow one simple, fast and flexible conversion and the ability to exchange two different roll cooling devices.

If the second roll cooling device is a shell cooling, then it can additionally be provided that the shell shape is adapted to the diameter range of the respective roll stand of a multi-stand rolling train and the base body of the shell cooling is selected to be the same for all stands. Thus, after optimizing a roll stand, a simple interchangeability of the neighboring stands with the same method and with the same second roll cooling devices with diameter-adapted shell shapes feasible.

If a shell cooling is used as the second roll cooling and if this cooling device and its media outlet are sealed off from its surroundings, it can furthermore be provided that neighboring aggregates (backup roll, chocks, possible cylinders, etc.) are cooled by small amounts of a cooling medium by means of, for example, spray cooling ,

LIST OF REFERENCE NUMBERS

1

cooler

2

roller

3

shoring

4 '

Cooling element of the first type

4 '

Cooling element of the second type

5

receiving element

6

mechanical interface

7

adapter

8th

fluidic interface

9

supply line

10

Means for adjusting the pressure / volumetric flow

10 '

Means for adjusting the pressure / volumetric flow

11

scraper

12

scraper

13

Verfahrzylinder

14

Cooling media supply

15

mounting screws

16

Lifting point cylinder / shoring

17

Roadway for shoring

18

spray nozzles

19

cooling tray

20

jet

21

Joint for cooling shell

22

Feedback lever

23

Joint for articulation lever

24

High-pressure media supply

25

Low pressure media supply

W

rolling direction

Claims (13)

Rolling train for rolling a metallic material, comprising a cooling device (1) for cooling the rolls (2) of a roll stand and / or the material to be rolled or rolled,
characterized,
that the cooling device (1) '", wherein at least two cooling elements (4 (4, 4, at least one supporting framework (3) for at least one cooling element 4)'') of different structure are available or are present, wherein the supporting framework (3 ) is equipped with at least one receiving element (5) which is designed to accommodate a cooling element (4 ', 4 ") of a selected type can alternatively. Rolling train according to claim 1, characterized in that the cooling element (4 ') of a type is a spray bar for spraying cooling medium onto the roll (2) and / or onto the material to be rolled. Rolling train according to claim 1, characterized in that the cooling element (4 ") of a type at least one cooling nozzle with a cooling shell for applying cooling medium to the roller (2). Rolling train according to claim 1, characterized in that the cooling element of a type is a high-turbulent cooling. Rolling train according to claim 1, characterized in that the cooling element of a type is a roller cooling with water curtain. Rolling train according to claim 1, characterized in that the cooling element of a type is an ultra-high pressure cooling. Rolling train according to claim 1, characterized in that the cooling element of a type is roll cooling with laminar tubes. Rolling train according to one of claims 1 to 7, characterized in that the receiving element (5) of the support frame (3) has a mechanical interface (6) which is designed for mechanical connection to an adapter (7) which on the cooling element (4 '. , 4 ") is arranged, wherein the adapter (7) of all cooling elements (4 ', 4") to the mechanical interface (6) of the receiving element (5) are designed to fit. Rolling train according to one of claims 1 to 8, characterized in that the receiving element (5) of the support frame (3) has a fluidic interface (8) which is designed for fluidic connection to the cooling element (4 ', 4 "). Rolling train according to one of claims 1 to 9, characterized in that in the support frame (3) at least one supply line (9) is arranged for cooling medium, wherein the supply line (9) means (10, 10 ') for adjusting the pressure of the cooling medium and / or the cooling medium volume flow. Method for operating a rolling mill with a cooling device (1) according to one of claims 1 to 10, comprising the steps: a) operating the rolling train using at least one cooling element (4 ') of a first type, wherein via the cooling element (4') cooling medium is discharged at a first pressure level and / or at a first volume flow; b) disassembly of the at least one cooling element (4 ') of the first type; c) mounting at least one cooling element (4 ") of a second type; d) operating the rolling train using at least one cooling element (4 ") of the second type, wherein via the cooling element (4") cooling medium is discharged at a second pressure level and / or with a second volume flow, which differs from the first pressure level and / or first volume flow is different. A method according to claim 11, characterized in that a first cooling element (4 ') with a supply pressure between 3 bar and 30 bar, preferably between 7 bar and 15 bar, operated, and that a second cooling element (4 ") with a supply pressure of less than 6 bar, preferably with a supply pressure between 1 bar and 5 bar, operated. A method according to claim 11 or 12, characterized in that a second cooling element (4 ") via a pressure reducing element (10 ') by a high-pressure medium supply (24) is operated.

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