EP3774099B1 - Cooling device and method for operating the same - Google Patents

Description

The invention relates to a cooling device for cooling a metallic item, in particular a metal strip. The invention also relates to a method for operating a corresponding cooling device.

Cooling devices of this type are well known in the prior art, for example from European patents EP 2 155 411 B1 and EP 2 986 400 B1 .

The European patent specification EP 2 155 411 B1 discloses a cooling device for influencing the temperature distribution across the width of a metallic material, in particular a rolled material. The cooling device has nozzles for applying a coolant to the metallic material, the nozzles being arranged distributed over the width. At least one of the nozzles can be adjusted in its position with respect to the width of the metallic material. This means that it is possible to influence non-uniform temperature distributions over the width of the metal strip to a limited extent. A subdivision of the cooling bar into individual spray areas is not known from this patent.

The subdivision of a cooling bar into individual spray areas is, for example, from the European patent EP 2 986 400 B1 known. Specifically, the cooling device disclosed there has at least one cooling beam which extends transversely to the transport direction of the metallic goods when they pass through the cooling device. The at least one cooling beam has - in its longitudinal direction, that is to say transversely to the transport direction of the metallic good - two outer and one central spray area arranged between the two outer spray areas. In each of the spray areas can be individually controlled via specially assigned Valves are fed a cooling medium, which is then applied to the metallic material to be cooled via the spray nozzles assigned to the respective spray area.

The Japanese patent application JP S59 041426 A discloses the features of the preamble of claim 1.

The invention is based on the object of developing a known cooling device and a known method for its operation in such a way that the application of coolant to the metallic goods is improved and the starting point of a degressive decrease or a positive increase in the volume flow of the coolant is variable along the longitudinal extent of the cooling beam becomes determinable.

This object is achieved by the subject matter of claim 1. Accordingly, at least one partition is provided in the at least one cooling beam of the cooling device according to the invention for dividing the interior of the cooling beam into at least two chambers, each of the spray areas being assigned to a different one of the chambers. The partition is shaped at least approximately according to the course of the temperature distribution in a predetermined width section of the metallic material before it enters the cooling device, and the partition wall is arranged in the cooling beam over this width section. Furthermore, the cooling device comprises at least one control element - also controllable by the control device - for the variable positioning of the partition walls within the cooling bar, in particular for moving the partition walls in the longitudinal direction of the cooling bar, and thus for changing the chambers and the spray areas of one cooling bar in each case

The claimed division of the interior of the cooling beam into a plurality of chambers with the help of partition walls and in particular the claimed special shape of the partition walls according to the course of the temperature distribution over the width of the goods to be cooled advantageously enables particularly effective and targeted cooling of the goods. In particular by the claimed shape of the partition walls, preferably in conjunction with a different supply of coolant into the chambers separated by the partition wall, the cooling can be adapted particularly well to the actual cooling requirement across the width of the goods. In this way, constant, degressive or progressive cooling strategies can advantageously be implemented over the width of the goods to be cooled.

As a result of this claimed movability of the separating elements, in particular the starting point of a degressive decrease or a positive increase in the volume flow of the coolant along the longitudinal extension of the cooling bar can be variably determined and suitably adapted to cooling requirements in individual cases. The starting point can be adjusted symmetrically on both sides based on the width of the goods to be cooled or, alternatively, asymmetrically only on one side of the goods to be cooled, depending on the temperature profile of the metallic goods entering the cooling device.

If, according to a first exemplary embodiment, at least one of the spraying areas has a plurality of spray nozzles distributed over the area of the spraying area, preferably arranged in parallel rows in the longitudinal direction of the cooling bar, this offers the advantage that over the width of the item to be cooled there are also curved or curved distributions of the coolant discharge are possible which run relatively smoothly, d. H. do not have excessive jumps or discontinuities in the transition between individual subsections of the distribution.

In relation to the center of the metallic material to be cooled, it can be advantageous to choose the arrangement and / or the number of spray nozzles in the spraying areas symmetrically or asymmetrically, depending on the temperature profile of the material entering the cooling device, with the temperature profile being modified in a suitable manner is.

Advantageously, at least three chambers are formed in a cooling beam, ie a left, a middle and a right spray area, because the Edge areas of the goods to be cooled generally require less cooling than the middle area of the goods to be cooled.

The cooling device can have a plurality of cooling bars arranged in parallel, which are each arranged above or below the item to be cooled. Such a group-wise combination of several chilled beams offers the advantage that the distribution of the coolant over the width of the goods is even smoother, i. H. can be implemented without jumps or pronounced kinks in the volume flow of the coolant.

The control device can be designed either in the form of a pilot control or in the form of a regulating device. In both cases, it is used to achieve a pre-calculated target distribution of the coolant across the width of the metal item. In both cases, the volume flow or the pressure of the coolant can be used by suitable setting of the valves and / or the actuators for positioning the partition walls to generate the respectively desired target distribution of the coolant over the goods to be cooled. The target distributions of the volume flow or the pressure of the coolant over the width of the goods to be cooled are preferably calculated using a cooling model. This applies both to the design of the control device in the form of a pilot control and to its design in the form of a regulating device.

The above-mentioned object of the invention is further achieved by a method according to the invention according to claim 14. The advantages of this method correspond to the advantages mentioned above with regard to the claimed device.

The partition walls can be moved outside or during ongoing cooling operations.

Further advantageous configurations of the cooling device according to the invention and the method according to the invention for its operation are the subject matter of the dependent claims.

Figur 1

die erfindungsgemäße Kühleinrichtung mit einem ersten Ausführungsbeispiel für die Formgebung der Trennwände;

Figur 2

die erfindungsgemäße Kühleinrichtung mit einem zweiten Ausführungsbeispiel für die Formgebung und Anordnung der Trennwände;

Figur 3

ein Beispiel für das erfindungsgemäße Kühlmodell

Figur 4

verschiedene Beispiele für die Realisierung des Volumenstromes des Kühlmittels über der Breite des zu kühlenden Gutes in Abhängigkeit der Temperaturverteilung des in die Kühleinrichtung einlaufenden Gutes; und

Figur 5

einen Kühlbalken mit variabler Positionierung der Trennwände und die Auswirkung der Verschiebung der Trennwände auf die Verteilung des Volumenstromes des Kühlmittels über der Breite des metallischen Gutes

zeigt.The description is accompanied by a total of 5 figures, with

Figure 1

the cooling device according to the invention with a first embodiment for the shaping of the partition walls;

Figure 2

the cooling device according to the invention with a second embodiment for the shaping and arrangement of the partition walls;

Figure 3

an example of the cooling model according to the invention

Figure 4

various examples for the implementation of the volume flow of the coolant across the width of the goods to be cooled depending on the temperature distribution of the goods entering the cooling device; and

Figure 5

a cooling beam with variable positioning of the partition walls and the effect of the displacement of the partition walls on the distribution of the volume flow of the coolant across the width of the metallic material

shows.

The invention is described in detail below in the form of exemplary embodiments with reference to the figures mentioned. In all figures, the same technical elements are denoted by the same reference symbols.

Figure 1 shows the cooling device 100 according to the invention for cooling a metallic good 200. The metallic good 200 passes through the cooling device 100 in the material flow direction x or in the transport direction T of the good. The cooling device 100 comprises according to Figure 1 for example a cooling beam 110 with a plurality, here for example N = 3, of spray areas I, II, III that are adjacent in pairs. These spray areas in turn each have at least one spray nozzle 130 for spraying a coolant onto the metallic material 200. In Figure 1 each of the spray areas I, II, III has a plurality of spray nozzles which are arranged distributed in the X and Y directions. By way of example and preferably, the spray nozzles 130 are each arranged to run in parallel regions in the longitudinal direction L of the cooling bar 110. According to the invention, the interior of the cooling bar 110 is subdivided into a plurality of chambers with the aid of partition walls 140. The partition walls can be arranged in a stationary or displaceable manner within the cooling bar. Each of these chambers is assigned to one of the spray areas I, II, III.

Furthermore, in Figure 1 three valves 120 can be seen by way of example for individually setting the pressure or the volume flow of the coolant in each of the spray areas I, II, III. The coolant 300 is fed individually from a coolant tank with the aid of a pump 160 through the valves 120 into the individual spray areas I, II, III. Finally, a control device 150 is provided for the individual control of the pump 160 and the valves 120.

In Figure 1 For example, two partition walls 140 are provided for dividing the cooling bar 110 into three chambers or three spray areas I, II, III. In relation to the center M of the metallic good, the three areas are designed symmetrically; this means that an equal number of spray nozzles is allocated to the middle spray area II to the right and left of the center in particular.

Furthermore shows Figure 1 the temperature distribution of the goods, typically measured with the help of a temperature determination device, over its width before entering the cooling device or before entering under the cooling beam 110. According to the present invention, the partition walls are shaped in a width section ΔY1, ΔY2 corresponding to the temperature profile over the same width section ΔY1, ΔY2 .

Figure 2 In contrast, shows a second embodiment for dividing the cooling bar 110 into individual chambers and spray areas, here five spray areas I, II, III, IV and V. Accordingly, five valves 120 are provided for individually feeding the coolant 300 into the individual chambers or spray areas . In contrast to the first embodiment according to Figure 1 is that with the in Figure 2 The second embodiment shown, the arrangement or the number of spray nozzles 130 relative to the center M of the metallic material asymmetrically. This can be seen in particular from the fact that more spray nozzles 130 are arranged in the right half of the central spray area III than in its left part.

In the Figures 1 and 2 In the illustrated embodiments, the partition walls 140 each run between the spray nozzles 130. In both embodiments, the partition walls are step-shaped; alternatively, however, they can also be designed to run straight or arcuate, in particular parabolic. As I said: Ideally, the partition walls are shaped exactly in accordance with the temperature distribution in a corresponding width section. In practice, it is often sufficient to approximate the shape of the partition walls to the temperature distribution, for example by means of the step or staircase function or a straight line. The number of chambers or spray areas per cooling beam is basically arbitrary. The more chambers or spray areas that are implemented, the more precisely a desired distribution for the coolant over the width of the product can be set.

According to one variant, the control device can be designed in the form of a pilot control for suitable setting of the valves 120 and / or the actuators 144 for positioning the partition walls with regard to setpoint values, in particular a calculated or predetermined setpoint distribution for the coolant 300 over the metallic material .

Alternatively, the control device 150 can also be designed in the form of a control device for regulating an actual distribution of the volume flow of the coolant to a predetermined target distribution of the coolant over the metallic material by variable control of the valves 120 and / or the adjusting elements 144 for the positioning of the Partition walls 140. The valve 120 and / or the actuating elements 144 then represent the actuators of the control loop.

To calculate the distribution of the coolant over the metallic material, in particular over its width as setpoint values for the pilot control or the control device, the use of a cooling model is recommended, as exemplified in FIG Figure 3 shown.

The cooling model is a computer program that is based on the in Figure 3 named primary data, the data available in a database of the cooling model and based on measurements, as in Figure 3 each named as an example, different setpoint values are calculated, in particular the setpoint distribution of the coolant over the width of the metallic item to be cooled. Alone Figure 3 The individual data or parameters or setpoints mentioned are to be understood as merely exemplary. This means that for the calculation of certain setpoints it is not absolutely necessary that all of the input variables mentioned as examples on the input side of the cooling model have to be used.

Figure 4 shows a selection of different temperature profiles over the width of the goods to be cooled before they enter the cooling device 100 according to the invention qualitative representation of exemplary useful cooling strategies. The dashed curve profile denotes the temperature profile of the metallic material before it enters the cooling device. The solid line shown above is characteristic of the distribution according to the invention of the coolant within the cooling device for treating the incoming temperature profile.

For example, in the figure above from Figure 4 It can be seen that the edges of the incoming metallic goods are less heated than in the middle, and accordingly the coolant volume flow at the edges only needs to be less pronounced than in the middle. Conversely, the middle figure in Figure 4 the example that the edges are more heated than the center. Accordingly, the coolant flow must be increased at the edges in order to achieve a uniform cooling profile over the entire width of the goods. While the top and middle figures in Figure 4 require a symmetrical distribution of the coolant, which goes hand in hand with a symmetrical division of the spray areas along the length of the cooling bar and a symmetrical arrangement of the spray nozzles and preferably also a symmetrical arrangement of the spray nozzles within the spray areas, as shown in the lower figure in Figure 4 an asymmetrical temperature and coolant curve. Specifically, it can be seen that the temperature at the left edge area shows no difference to the center of the goods, while the temperature in the right edge area has dropped significantly. Accordingly, the coolant distribution required for this in the left edge area must be almost constant or unchanged compared to the central area of the goods to be cooled, while the output of the coolant volume flow at the right edge must be significantly reduced.

Figure 5 Finally, FIG. 8 shows an exemplary embodiment of the present invention in which the partition walls 140 can be moved in the longitudinal direction of the cooling bar 110. As in the figure below of Figure 5 can be seen, a movement of the partition walls 140 causes a shift in the starting time for the Beginning of a degressive course of the coolant distribution. Specifically, the right and left partition walls 140 in the in Figure 5 the embodiment shown move outwards (see dashed line); This has the consequence that the starting times for the degressive decrease in the coolant volume flow are shifted to the right and left to the outside, ie towards the edges of the metallic material.

List of reference symbols

100

Cooling device

110

Chilled beams

120

Valves

130

Spray nozzles

140

Partitions

144

Adjusting elements for positioning the partition walls

150

Control device

160

pump

200

metallic good

300

Coolant

400

Cooling model

I, II, III

Splash areas

L, x

Longitudinal direction of the cooling bar

M.

Middle of the metallic good

n, N

Number of spray areas

T, Y

Direction of transport of the metallic goods

Temp

Temperature (distribution)

ΔY1, ΔY2

Width sections

Claims (16)

1. Cooling device (100) for cooling a metallic product (200), comprising:

   at least one cooling bar (110) with a plurality N of spraying regions (I, II, III) adjacent in pairs, each spraying region having at least one spray nozzle (130) for spraying a coolant on the metallic product;

   valves (120) for individual setting of the pressure or the volume flow of the coolant (300) in each of the spraying regions (I, II, III);

   a control device (150) for individual activation of the valves (120); and

   a temperature determining device for determining the distribution of the temperature of the metallic product over its width before entry of the metallic product into the cooling device;

   wherein at least one partition wall (140) is provided for dividing the interior of the cooling bar (110) into at least two chambers,

   wherein each of the spraying regions (I, II, III) is assigned to a different one of the chambers;

   wherein the partition wall is shaped at least approximately in accordance with the course of the temperature distribution in a predetermined width section of the metallic product before entry into the cooling device; and

   the partition wall is arranged in the cooling bar over this width section,

   characterised in that

   at least one setting element (144), which is also activatable by the control device (150), is provided for the variable positioning of the partition wall (140) within the cooling bar (110),

   in particular for moving the partition wall (140) in the longitudinal direction (L) of the cooling bar, and thus for changing the chambers and the spraying regions (I, II, III) of a cooling bar (110).
2. Cooling device (100) according to claim 1,

   characterised in that

   at least one of the spraying regions (I, II, III) has a plurality of spray nozzles (130) distributed in the x direction and y direction, preferably arranged to run in parallel rows in the longitudinal direction (L) of the cooling bar (110).
3. Cooling device (100) according to one of the preceding claims,

   characterised in that

   the arrangement and/or number of spray nozzles (130) in the spraying regions of the cooling bar is or are symmetrical or asymmetrical in the width direction in relation to the centre (M) of the metallic product.
4. Cooling device (100) according to any one of the preceding claims,

   characterised in that

   the partition walls (140) run between the spray nozzles (130).
5. Cooling device (100) according to any one of the preceding claims,

   characterised in that

   the partition walls (140) are formed to be straight, step-shaped or curved, in particular parabolic.
6. Cooling device (100) according to any one of the preceding claims,

   characterised in that

   for a whole-number plurality N of chambers within the cooling bar the relationship N ≥ 3 applies.
7. Cooling device (100) according to claim 6,

   characterised in that

   when N = 3 there is a left, a middle and a right spraying area (I, II, III), each of which is trapezoidal.
8. Cooling device (100) according to any one of the preceding claims,

   characterised in that

   in each case several cooling bars arranged in parallel are combined to form a group.
9. Cooling device (100) according to any one of the preceding claims,

   characterised in that

   the control device (150) is configured in the form of a pilot control for suitable setting of the valves (120) and/or the actuators (144) for positioning the partition walls (140) with respect to target values, in particular a calculated target distribution for the coolant (300) over the metallic product (200).
10. Cooling device (100) according to any one of claims 1 to 8,

    characterised in that

    the control device (150) is configured in the form of a regulating device for regulating an actual distribution of the volume flow or the pressure of the coolant (300) to a predetermined target distribution of the volume flow or of the pressure of the coolant over the metallic product (200) by suitable variable activation of the valves (120) and/or the setting elements (144) for the positioning of the partition walls (140), wherein the valves and/or the adjusting elements represent the actuators of the control loop.
11. Cooling device (100) according to claim 9 or 10,

    characterised in that

    a cooling model (400) for calculating the target distribution, in particular the volume flow or the pressure, of the coolant over the metallic product (200), in particular over its width, for the pilot control or the control device.
12. Cooling device (100) according to claim 11,

    characterised in that

    the cooling model (400) is additionally designed to calculate the target distribution of the coolant over the metallic product (200) as a function of the following measured variables supplied to the cooling model:

    - the temperature or the temperature course of the product (200), preferably in the length and width direction thereof at the inlet and/or outlet of the cooling device, in particular in front of and/or behind the cooling bar; and/or

    - the actual characteristic of the product (200), for example the hardness, viscosity or residual austenite content, at the outlet of the cooling device; and/or

    - the temperature of the cooling during spraying onto the metallic product (200).
13. Cooling device (100) according to any one of the preceding claims,

    characterised in that

    the number of spraying regions (I, II, III) with individual coolant feed and/or the number of spray nozzles (130) per unit area of a spraying region is or are selected as a function of a desired coolant exposure density.
14. Method for operating a cooling device (100) according to any one of the preceding claims,

    characterised in that

    the partition walls (140) between two adjacent spraying areas (I, II, III) are preferably suitably moved in the longitudinal direction (L) of the cooling bar (110) for adaptation of the position of the partition walls to the course of the temperature distribution of the metallic product over its width before entry into the cooling device or for setting a desired target distribution of the pressure or the volume flow of the coolant (300) over the width of the metallic product (200).
15. Method according to claim 14,

    characterised in that

    the partition walls (140) on both sides of the centre (M) of the cooling bar (110) are moved symmetrically or asymmetrically with respect to the centre (M) of the cooling bar (110).
16. Method according to one of claims 14 and 15,

    characterised in that

    the movement of the partition walls - in particular as part of the pilot control or the regulation of the position of the partition walls - can also take place during ongoing cooling operation.

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