EP2809460B1 - Device for straightening a flow for cooling a roll or a metal strip - Google Patents

Description

Field of the invention

The present invention relates to a device for directing a flow for cooling a roll or a metal strip or a flow straightener. Furthermore, the present invention relates to a device for cooling a roller or a metal strip.

State of the art

Numerous cooling devices for cooling rolls, metal strips or metal sheets are known in the prior art, with air, oil emulsions or water being used for cooling, for example.

In some cases, cooling medium via Kühlmediumauslässe is simply applied in large quantities on the roll to be cooled or the belt to be cooled. The disadvantage of this is, inter alia, a large amount of used cooling medium, which is either lost for further processes or consuming recycled and possibly processed. Another disadvantage is the poor heat transfer rate per unit volume of applied cooling medium. Also, a controlled and different degrees of cooling in the width direction of the roller or the belt is not possible with many known devices.

Further developed devices include spray bars which extend across the width of the belt or roller. Such spray bars often comprise a hollow body which can be filled with cooling water and which comprises outlet openings along the width direction, from which cooling water can reach the strip.

The JP 11057837 A discloses, for example, a cooling device in which water can be passed from a container to the metal strip via a slot extending in the width direction of a metal strip. A disadvantage of such constructions, however, is that the water still flows undirected on the metal strip. The relative velocity between the water to be cooled and the metal strip is low and the water used is not sufficiently used for cooling. In addition, the exiting from such a cooling device streams are highly turbulent, undirected and / or have at their exit a considerable boundary layer thickness. Turbulent coolant flows with large boundary layer thickness generally result in a relatively poor heat transfer coefficient and thus reduce cooling efficiency. Another disadvantage is that the currents generated are not sufficiently defined or known or calculable, whereby the control or regulation of the cooling is difficult.

In summary, the technical problem is to provide a device that contributes to a more efficient cooling of a roll or metal strip.

In particular, there should be provided a device for directing a flow which can produce a low turbulence, a low boundary layer, or a directional flow.
Another object is to provide an improved apparatus for cooling a roll or strip of metal. Preferably, at least one of the above-mentioned disadvantages should be avoided.
The Belgian patent application BE 870 960 A1 discloses a device for directing a Kühlmedlumstroms for cooling a metal strip. This device comprises a hollow body extending over the width of the metal strip and a tube arranged in the hollow body and extending in the width direction of the metal strip.

Disclosure of the invention

The asked technical problem is solved by the device for directing a cooling medium flow for cooling a roll or a metal strip according to claim 1. This device preferably comprises a hollow body extending over at least part of the width of the roller or the metal strip and a tube arranged in the hollow body and extending in the width direction (perpendicular to the direction of rolling or rolling) of the roller or metal strip, the hollow body being in the width direction the roller or the metal strip is divided into a plurality of chambers (segments) and the tube openings for introducing cooling medium into the chambers of the hollow body and the chambers each comprise an opening for the outflow of cooling medium from the hollow body. Furthermore, the chambers according to the invention each comprise a channel formed between the inner wall of the hollow body and the pipe for conducting cooling medium from the openings of the pipe to the opening for the outflow of cooling medium from the hollow body, wherein the flow cross-section of the channel tapers at least at its downstream end or extended to its downstream end.

By this arrangement and the provision of a tapered shape of the channel, the fluid is accelerated and directed. Thus, turbulence can be reduced and the boundary layer can be reduced. The term of the boundary layer is familiar to those skilled in the field of fluid dynamics. Most often, the thickness of the boundary layer of fluid flow is considered to be the thickness in which the flowing fluid has less than 99% of its free outer velocity. Furthermore, by the division of the hollow body into a plurality of chambers (in the width direction) also a directivity can be achieved.

The openings of the tube are preferably in all embodiments on the side facing away from the opening of the hollow body side, so that the cooling medium leaves the tube in a flow direction, which is directed opposite to the flow direction at exit from the hollow body substantially. After its exit from the tube, the cooling medium is therefore deflected by appropriate guidance along the outside of the tube.

According to a preferred embodiment, the tube is arranged in the interior of the hollow body and at least for the most part (more than half of its Circumference) of cooling medium flow around. In general, the tube can be arranged substantially centered with respect to the hollow body or its inner wall.

According to a further preferred embodiment, the channel formed tapers downstream at least from half its length continuously up to the opening for outflow from the hollow body. Through a continuous taper of the channel in the flow direction, a flow with even less turbulence can be generated by the device.

According to a further preferred embodiment, the chambers are each separated from each other by a partition wall. The partition separates the cavity of the hollow body in the width direction, but the flow of cooling medium through the tube is still possible. Preferably, the partitions extend in a direction substantially perpendicular to the width direction of the roll or the metal strip.

According to a further preferred embodiment, at least some of the chambers of the hollow body comprise a flow dividing wall extending essentially opposite the opening for the outflow of cooling medium from the hollow body, and at least two openings arranged in the pipe for passing coolant into the respective chamber. In this case, the openings for conducting coolant into the respective chamber are each arranged on one of the sides of the flow dividing wall for dividing cooling medium emerging from the openings of the pipe into two partial flows, so that when cooling medium leaks out of the openings of the pipe, the two partial flows each ( between tube and inner wall of the hollow body or the respective chamber delimited) are separated from each other on opposite sides of the tube in the direction of the opening for the outflow of cooling medium from the hollow body to be passed and unite there to the cooling medium flow or a common cooling medium flow.

In other words, a partial flow within a chamber from one of the two openings of the tube in a region opposite the outlet of the hollow body between the inner wall of the hollow body and the outer wall of the tube is preferably directed into a tapered channel to the outlet of the hollow body. Preferably, the channel tapers at least in sections. The two partial flows are preferably separated from each other in a region of the hollow body opposite the outlet of the hollow body by a flow dividing wall.

According to a further preferred embodiment, the hollow body and optionally also the tube perpendicular to the width direction of the roller or the metal strip on a triangular cross section, wherein the outlet of the hollow body is located substantially at a tip of its triangular cross section. Such a shape of the hollow body or of the tube can in particular be made easily and is also extremely effective for producing a directed and accelerated flow.

The distance between an inner wall extending in the direction of the outlet of the hollow body and an outer wall of the pipe lying opposite this inner wall preferably decreases in the flow direction of the cooling medium or downstream. Furthermore, such a form simplifies the predictability of a cooling flow through the device. In general, flows through the cooler can be calculated or approximated using numerical simulations.

According to a further preferred embodiment, the hollow body and optionally also the tube perpendicular to the width direction of the roller or the metal strip on a teardrop-shaped cross-section. In this case, the hollow body at the tip of the drop-shaped cross section on the outlet of the hollow body. Such a drop-like shape serves to generate even less turbulent flows. In particular, accounts in such a form all corners and edges.

According to a further preferred embodiment, the inner wall of the cavity is edge-free. Preferably, the inner wall of the cavity is free of protruding edges or free of protruding kinks.

Furthermore, the present invention comprises a device for cooling a roll or a metal strip with a cooling shell which can be set against a roll or a metal strip and at least one nozzle for introducing a flow of cooling medium into a gap between the cooling shell and the roll or the metal strip, wherein the nozzle has an inlet region and an outlet region for the cooling medium flow and the device for cooling a roll or a metal strip further comprises a device for directing a cooling medium flow according to one of the above embodiments, wherein the openings for discharging cooling medium from the hollow body open into the inlet of the nozzle.

Especially by means of such an arrangement, a directed flow can be used particularly advantageously and efficiently for cooling.

According to a further preferred embodiment of the device for cooling a roll or a metal strip, the outlet region of the nozzle opens into the gap between the cooling shell and the roll or metal strip.

According to a further preferred embodiment of the device for cooling a roll or a metal strip, the outlet region of the nozzle is connected to the cooling shell and at least partially enclosed by the cooling shell so that cooling medium can flow from the nozzle into the cooling shell.

Preferably, the nozzle is arranged to introduce a cooling medium flow substantially tangentially to the metal strip or roll surface in the gap.

According to a further preferred embodiment of the device for cooling a roller or a metal strip, the outlets of the hollow body open into the inlet region of the nozzle and are optionally connected to the nozzle.

According to a further preferred embodiment of the device for cooling a roll or a metal strip, the cooling shell extends over at least part of the width and / or circumference of the roll. If a metal strip is to be cooled, the cooling shell preferably extends over at least part of the width and / or the length of the metal strip.

In general, the outlet of the nozzle can be arranged such that the metal strip surface or the roll surface against the direction of movement of the roller or the belt can be flowed through the nozzle.

All features of the embodiments described above can be combined with each other or replaced.

Brief description of the figures

Figur 1

einen Teil einer erfindungsgemäßen Vorrichtung zum Kühlen einer Walze;

Figur 2

einen senkrecht zur Breitenrichtung liegenden schematischen Querschnitt eines Strömungsrichters gemäß einem erfindungsgemäßen Ausführungsbeispiel;

Figur 3

einen in Breitenrichtung liegenden schematischen Querschnitt des Strömungsrichters gemäß Figur 2;

Figur 4

einen senkrecht zur Breitenrichtung liegenden schematischen Querschnitt eines Strömungsrichters gemäß einem weiteren erfindungsgemäßen Ausführungsbeispiel;

Figur 5

eine Vorrichtung zum Kühlen eines Metallbandes gemäß einem erfindungsgemäßen Ausführungsbeispiel;

Figur 6

einen senkrecht zur Breitenrichtung liegenden schematischen Querschnitt eines Strömungsrichters gemäß einem weiteren erfindungsgemäßen Ausführungsbeispiel; und

Figur 7

einen senkrecht zur Breitenrichtung liegenden schematischen Querschnitt eines Strömungsrichters gemäß einem weiteren erfindungsgemäßen Ausführungsbeispiel.

The figures of the embodiments will be briefly described below. Further details can be found in the detailed description of the embodiments. Show it:

FIG. 1

a part of a device according to the invention for cooling a roller;

FIG. 2

a lying perpendicular to the width direction schematic cross-section of a flow straightener according to an embodiment of the invention;

FIG. 3

a lying in the width direction of the schematic section of the flow straightener according to FIG. 2 ;

FIG. 4

a vertical cross-sectional schematic cross section of a flow straightener according to another embodiment of the invention;

FIG. 5

an apparatus for cooling a metal strip according to an embodiment of the invention;

FIG. 6

a vertical cross-sectional schematic cross section of a flow straightener according to another embodiment of the invention; and

FIG. 7

a lying perpendicular to the width direction schematic cross-section of a flow straightener according to another embodiment of the invention.

Detailed description of the embodiments

FIG. 1 discloses a part of a device according to the invention for cooling a roll 2. The roll may be a work roll 2 for rolling a metal strip 200 as shown. Such a roll 2 may also be supported by a backing roll 300 and cooled by cooling medium (such as gas, air, water, oil or mixtures of these materials) for cooling the roll surface. For this purpose, a cooling shell 40 can preferably be attached to a part of the circumference U of the roll 2. By means of a nozzle 41, a cooling medium flow into the gap 43 between the roller surface and the cooling shell 40, as through the Marked flow lines, initiated. In this case, the cooling shell 40 extends at least over part of the roll width in the width direction B. The width direction B is perpendicular to the rolling or casting or strip running direction W. The distance of the cooling shell 40 of the roll surface (the gap height) can be variable or be adjustable. For this purpose, a suitable adjusting device (not shown) can serve, which can adjust the gap distance hydraulically, pneumatically mechanically or electromechanically, for example. By passing a cooling medium flow through the gap 43, the roll surface is cooled. Among other things, in addition to the volume flow or the pressure of the supplied cooling medium, the type or shape of the flow plays a role.

In particular, it is desirable that the flow is as laminar as possible or less turbulent. The reduction of turbulence and / or the reduction of the boundary layer thickness results in that the heat transfer between the roller and the cooling medium flow in the gap 43 is improved. Furthermore, it is desirable to achieve the highest possible relative velocity of the flow and the surface to be cooled. The flow rate has a significant influence on the heat transfer coefficient and thus on the cooling effect. For this purpose, the flow is preferably introduced counter to the direction of rotation D of the roller 2 in the gap 43.

Like also in the FIG. 1 As shown, the nozzle 42 may include a downstream tapered shape for conducting the cooling medium, which includes an inlet region 45 and an outlet region 46. The nozzle 41 preferably leads the cooling medium into the gap 43 in a curved line or shape tangentially to the roll surface. The nozzle 41 can form part of the cooling shell 43 or be connected to it. Furthermore, the nozzle 43 may extend over at least part of the width of the roller 2 and / or the cooling shell 40 extend. The nozzle 40 may be formed slit-like or formed by a plurality of separate, arranged in the width direction of B nozzles.

In order to avoid that cooling medium reaches the rolled metal strip 200, a scraper 400, which has a substantially plate-like shape, can also be arranged at the downstream end of the cooling shell 40. Such a scraper may for example be made of wood, hard tissue or metal.

To direct cooling medium into the gap 43, the nozzle inlet 45 must be supplied with cooling medium. This can be done, for example, with a variant according to the invention of a onflow device or a flow straightener 1, as described in US Pat FIG. 2 is shown.

The in the FIG. 2 Device 1 for directing a cooling medium flow shown can preferably have one or more openings 8, from which cooling medium can be fed to the inlet region 45 of the nozzle 41. For example, it is possible for the opening 9 to have the same cross-section A 'as the nozzle inlet 45 (cross-section A) to reduce turbulence. The device 1 preferably comprises a hollow body 3, which can extend in the width direction B. In the body 3, a (distributor) tube 5 is preferably arranged, which also extends in the width direction B, whose outer diameter is preferably smaller than the inner diameter of the hollow body 3. The tube 5 can be filled via at least one inlet 6. Inlets or feed pipes 6 can generally be introduced into the pipe 5 in any desired manner, for example radially or axially to the pipe 5. Furthermore, several feeds 6 can be distributed along the pipe 5 (in the width direction B). In this case, the tube 5 comprises openings (for example bores) which enter the hollow body 3 open. Preferably, these openings are arranged on one side of the tube 5, which is opposite to the opening 8 of the hollow body 3 substantially. The exact shape or the exact cross section of the hollow body 3 or the tube 5 is irrelevant to the invention. Preferably, however, a channel formed between the inner wall of the hollow body and the tube 5 should taper in the direction of the opening 9 of the hollow body 3. In other words, the hollow body 9 should enclose a channel which tapers towards a downstream end at least in sections or tapers at a downstream end. Preferably, the inner wall of the hollow body is edge-free or free of protruding corners or edges. As in particular in the FIG. 2 illustrated, the device 1 preferably comprises a partition wall 15, which extends substantially fluid-tightly between the opposite side of the opening 8 of the tube 5 and the inner wall of the hollow body 3. In this case, at least two outflow openings 9 are preferably arranged in the tube 5 such that in each case one of the outflow openings 9 directs cooling medium out of the tube 5 onto one of the two sides of the dividing wall 15.

The various outflow openings 9 of the tube 5 may preferably have different flow cross-sections in the width direction B. On the other hand, it is possible that the number of openings 9 varies in the width direction B. By a larger number of openings 9 in the center of the device 1 and a larger flow cross-section of the openings 9 in the center of the device compared to the ends lying in the width direction B of the device 1 and the tube 5, for example, the roll center or Melt center be cooled more than the edge areas.

Preferably, the hollow body 3 in one of its opening 8 facing half, in the direction of the opening 8 converging inner walls.

From the openings 9 exiting cooling medium is thus preferably divided into two partial streams and passed between the tube 5 and the inner wall of the hollow body 3 in the direction of the opening 8 of the hollow body.

The device 1 is divided in the width direction B into a plurality of chambers 7 or coolant-carrying chambers 7, wherein the FIG. 2 a perpendicular to the width direction B cross-section through one of the chambers 7 shows.

The Indian FIG. 7 illustrated cross section in the width direction B shows the adjacent in the width direction chambers 7, which are preferably separated by partitions 14 from each other. In other words, the partitions 14 extend perpendicular to the width direction B. The partitions are preferably interrupted only by the pipe 5 or the leads 6. Further elements of the device 1 are in the FIG. 3 with the same reference numerals as in the FIG. 2 shown.

An opening 8 and two openings 9 for introducing cooling medium into the chamber 7 are preferably arranged in at least one of the chambers 7. The openings 9 are preferably arranged on two sides of a flow dividing wall 15. Additional openings or outlets 8, 9 are possible.

The preferably fluid-tight segmentation or chamber-like subdivision of the hollow body 3 in the width direction B, inter alia, ensures that the currents generated by the device 1 are aligned perpendicular to the width direction.

The chamber width can vary depending on the cooling medium used. It may for example be between 0.5 and 15 cm and preferably between 2 and 10 cm.

Also, such a segmentation can serve to provide different amounts of cooling medium or different streams in the width direction B.

According to the in the FIG. 4 1, the device 1 additionally comprises a movable or pivotable diaphragm or shell 13 for varying the clear diameter (the flow cross section) of the openings 9 of the tube 5. It is possible that a separately controlled diaphragm 13 is provided for each of the chambers 7. The illustrated aperture 13 essentially comprises a shape which is at least partially complementary to the inner shape of the tube 5. Wherein the aperture 13 can close the openings 9 pivoting. However, other shapes of the aperture 13 are possible, such as plug-like panels that close the opening 9 in a substantially perpendicular to the opening 9 movement and release it again. Otherwise, controllable valves can also be provided at the openings 9. In general, the diaphragms 13 are preferably arranged inside the tube 5, but may also be arranged outside the tube 5.

By controlling the means 13 for variably closing the openings 9, a width-varying volume flow of cooling medium can be generated. Preferably, the diaphragms are designed adjustable such that the strip or roller center is more coolable by applying larger amounts of coolant than the edge regions. In principle, however, viewed in the direction of width, edge-emphasized cooling is also possible or a constant application of cooling medium over the strip or roll width.

An adjustment of the aperture 13 or valves can be done, for example, mechanically hydraulic, electric, pneumatic and optionally wirelessly controlled.

The FIG. 5 discloses an inventive embodiment of an apparatus for cooling a metal strip 20. As shown, the metal strip 20 moves in the rolling direction W, which is perpendicular to the width direction B of the metal strip 20. On at least one of the broad sides of the belt 20 is a cooling shell 60. In the FIG. 5 Such cooling shells 60 are arranged on both sides of the belt 20. It is possible that the distance of the cooling shells 60 from the surface of the metal strip 20 is adjustable. These devices can serve, as they are already analogous in terms of FIG. 1 have been described. Between a cooling shell 60 and the strip surface there is a gap 63 through which cooling medium can pass. The cooling medium is preferably introduced into the gap 63 via a nozzle 61. Such a nozzle 61 may include an inlet 65 and an outlet region 66. As already in relation to the FIG. 1 described cooling medium is preferably introduced counter to the direction of the surface to be cooled. Furthermore, the cooling medium flow from the nozzle 61 is preferably guided tangentially to the metal strip surface in the gap 63. In the FIG. 5 The device shown further comprises a device 10 according to the invention for directing a cooling medium flow. This device 10 may, for example, one of the in the FIGS. 2 to 4 and 6 and 7 shown devices.

The FIG. 6 shows a further inventive embodiment of a flow straightener 11. The hollow body 30 and the inner wall is formed substantially with a triangular cross-section. In the hollow body 30, a tube 50 is arranged, which performs an analogous function to the tube 5 FIG. 2 exercises. Unlike in the FIG. 2 illustrated embodiment, However, the tube 50 has a triangular cross-section. Between the inner wall of the hollow body 30 and the outer wall of the tube 50, a channel 22 is formed, which tapers in the direction of the outlet 80 from the hollow body or the chamber 7 shown. Preferably, the tube 50 opposite the opening 80 with the cross section A 'at least two openings 90 for conducting cooling medium from the tube 50 into the channel 20. Preferably, in addition, a flow dividing wall 15 can be arranged between the two openings 90. However, this is not essential. Coolant exiting from the openings 90 can thus be divided into two partial flows, which are conducted on opposite sides of the tube 50 between the tube 50 and the inner wall of the hollow body 30 in the direction of the outlet 80 from the hollow body 30 or the segment 7 of the hollow body 30 ,

In general, the channel may include two (separate) channels on both sides of the tube. The flow cross-section may preferably taper or reduce in size in both channels downstream or in the direction of the outlet from the hollow body.

The FIG. 7 shows a further inventive embodiment of a flow straightener 111. The structure is basically similar to that in the FIG. 6 shown construction. However, the hollow body 33 and the tube 55 have a teardrop-shaped cross-section. Such a cross-section may also be described by a shape having at one end a round substantially semicircular or semi-elliptical shape and subsequently closing in an acute converging shape. The channel 222 formed between the tube 55 and the inner wall of the cavity 33 opens into an outlet 88, which preferably has the cross section A 'and is arranged substantially at the tip of the drop shape. As previously described with respect to other embodiments, openings 99 are in the Pipe 55 is provided, which are provided substantially on a side opposite to the outlet 88 of the tube 55. Between at least two such openings 99, a flow dividing wall 15 is preferably formed. The illustrated arrangement of the tube 55 in the hollow body 33, two partial flows can be generated, which each extend from one of the openings 99 of the tube 55 to the outlet 88 of the hollow body 33 and the respective chamber 7. Preferably, the flow cross-section of the channel 222 or of the channels is reduced at least from half of the channel length (considered in the flow direction).

In general, the shape of a nozzle 41, 61 and / or a device 1, 10, 11, 111 can be optimized by means of numerical simulations. Furthermore, depending on the specific application, the skilled person can regulate the pressure of the cooling medium or the volume flow provided. For example, a numerical simulation can take into account the pressure, the flow rate, the material constant of the coolant, or the temperature. This may also depend on the shape and arrangement of the nozzle 41, 61 used.

The gap height between a cooling shell and a roll or strip surface to be cooled may, for example, be between 0.1 cm and 2.5 cm and preferably between 0.2 cm and 1 cm.

The inlet region of the nozzle may, for example, have a light dimension or a flow cross-section which corresponds to 2 to 20 times the gap height. The outlet area of the nozzle may preferably taper to a dimension which corresponds to 1 to 3 times the gap height.

Cooling medium may preferably be supplied to apparatus 1, 10, 11 or 111, for example at pressures of less than 5 bar or, in particular, at pressures of less than 1 bar.

Above all, the embodiments described above serve to better understand the invention and should not be understood as limiting. The scope of protection of the present patent application results from the patent claims.

The features of the described embodiments can be combined with each other or exchanged for each other. This applies in particular to the embodiments of the Figures 2 . 4 . 6 and 7 ,

Furthermore, the features described can be adapted by the skilled person to existing circumstances or existing requirements.

LIST OF REFERENCE NUMBERS

1

Device for directing a cooling medium flow / flow straightener

2

Roller / stripper

3

hollow body

5

pipe

6

Supply line / feed tube

7

Chamber / chamber

8th

Opening for the discharge or release of cooling medium from the hollow body

9

Opening for introducing coolant from the tube into the hollow body

10

Device for directing a cooling medium flow / flow straightener

11

Device for directing a cooling medium flow / flow straightener

12

channel

13

cover

14

Partition between two chambers

15

Flow partition in a chamber

20

metal band

22

channel

33

hollow body

40

cooling tray

41

jet

43

gap

45

Inlet area of the nozzle

46

Outlet area of the nozzle

33

hollow body

60

cooling tray

61

jet

63

gap

65

Inlet area of the nozzle

66

Outlet area of the nozzle

80

Opening for the outflow of the cooling medium from the hollow body

88

Opening for the outflow of the cooling medium from the hollow body

90

Opening for directing cooling medium from the tube into a chamber

99

Opening for directing cooling medium from the tube into a chamber

111

Device for directing a cooling medium flow

200

metal band

222

channel

300

supporting roll

400

scraper

A

Cross section of the inlet area of the nozzle

A '

Cross section of the discharge opening of a flow straightener

B

width direction

D

Direction of rotation of the roller

U

Circumferential direction of the roller

W

Rolling direction / strip running direction

Claims (15)

1. A device (1, 10, 11, 111) for directing a flow of cooling medium for cooling a roll (2) or a metal strip (20), comprising:

   a hollow body (3, 30, 33) extending over at least a part of the width of the roll (2) or of the metal strip (20); and

   a tube (5, 50, 55) arranged in the hollow body (3, 30, 33) and extending in the width direction (B) of the roll (2) or the metal strip (20);

   characterised in that

   the hollow body (3, 30, 33) is divided in the width direction (B) of the roll (2) or the metal strip (20) into a plurality of chambers (7) and the tube (5, 50, 55) has openings (9, 90, 99) for conducting cooling medium from the tube (5, 50, 55) into the chambers (7) of the hollow body (3, 30, 33) and the chambers (7) each have an opening (8, 80, 88) for outflow of cooling medium from the hollow body (3, 30, 33); and

   the chambers (7) each have a channel (12, 22, 222), which is formed between the inner wall of the hollow body (3, 30, 33) and the tube (5, 50, 55), for conducting cooling medium from the openings (9, 90, 99) of the tube (5, 50, 55) to the opening (8, 80, 88) for outflow of cooling medium from the hollow body (3, 30, 33) and the flow cross-section of the channel (12, 22, 222) narrows at least at its downstream end.
2. The device according to claim 1, wherein the tube (5, 50, 55) is so arranged in the interior of the hollow body (3, 30, 33) that it can be flowed around to the greatest part by cooling medium.
3. The device according to claim 1 or 2, wherein the channel (12, 22, 222) continuously narrows from at least half its length as considered in downstream direction.
4. The device according to any one of the preceding claims, wherein the chambers (7) are each separated from one another by a respective separating wall (14) which separates the cavity of the hollow body (3, 30, 33) in the width direction (B), but enables flow of cooling medium through the tube (5, 50, 55) to the chambers (7).
5. The device according to claim 4, wherein the separating wall (14) extends substantially perpendicularly to the width direction (B) of the roll (2) or of the metal strip (20).
6. The device according to any one of the preceding claims, wherein at least some of the chambers (7) comprise a flow separating wall (15), which extends substantially opposite the opening (8, 80, 88) for outflow of cooling medium from the hollow body (3, 30, 33), and have at least two openings (9, 90, 99), which are arranged in the tube (5, 50, 55) substantially opposite the opening (8, 80, 88) of the hollow body (3, 30, 33), for conducting cooling medium into the chambers (7), wherein the openings (9, 90, 99) for conducting cooling medium into the chambers (7) are each arranged on one of the sides of the flow separating wall (15) and the flow separating wall (15) divides cooling medium, which exits the openings (9, 90, 99) of the tube (5, 50, 55), into two sub-flows which are each bounded by the tube (5, 50, 55) and the inner wall of the hollow body (3, 30, 33), are guided separately from one another on opposite sides of the tube (5, 50, 55) in the direction of the opening (8, 80, 88) for outflow of cooling medium from the hollow body (3, 30, 33) and are there combined to form a common cooling medium flow.
7. The device according to any one of the preceding claims, wherein at least some of the chambers (7) of the hollow body (3, 30, 33) and selectably also the tube (5, 50, 55) have a triangular cross-section perpendicularly to the width direction (B) of the roll (2) or the metal strip (20) and the outlets (8, 80, 88) of the chambers (3, 30, 33) are each located substantially at an apex of the triangular cross-section,.
8. The device according to any one of claims 1 to 6, wherein at least some of the chambers (7) of the hollow body (3, 30, 33) and selectably also the tube (5, 50, 55) have a drop-shaped cross-section perpendicularly to the width direction (B) of the roll (2) or the metal strip (20) and the outlets (8, 80, 88) of the chambers (3, 30, 33) are located substantially at an apex of the drop-shaped cross-section.
9. The device according to any one of the preceding claims, wherein the inner wall of the hollow body (3, 30, 33) is free of protruding edges.
10. The device according to any one of the preceding claims, wherein the device additionally comprises means for setting the throughflow quantity of cooling medium through the openings (9, 90, 99) of the tube (5, 50, 55), which means preferably comprise one or more controllable, movable aperture plates (13) or at least one controllable valve.
11. A device for cooling a roll (2) or a metal strip (20), comprising:

    a device (1, 10, 11, 111) for directing a flow of cooling medium according to any one of the preceding claims;

    a cooling shell (40, 60) adjustable relative to a roll (2) or a metal strip (20); and

    at least one nozzle (41, 61) for conducting a flow of cooling medium into a gap (42, 63) between the cooling shell (40, 60) and the roll (2) or the metal strip (20),

    wherein the nozzle (41, 61) has an inlet region (45, 65) with a defined throughflow cross-section (A, A') and an outlet region (46, 66) for the cooling medium flow; and

    wherein the openings (8, 80, 88) for outflow of cooling medium from the hollow body (3, 30, 33) open into the inlet region (45, 65) of the nozzle (41, 61).
12. The device for cooling a roll (2) or a metal strip (20) according to claim 11, wherein the outlet region (46, 66) of the nozzle (41, 61) opens into the gap (43, 63) between cooling shell (40, 60) and roll (2) or metal strip (20).
13. The device for cooling a roll (2) or a metal strip (20) according to claim 11 or 12, wherein the outlet region (46, 66) of the nozzle (41, 61) is connected with the cooling shell (40, 60) and at least partly enclosed by this.
14. The device for cooling a roll (2) or a metal strip (20) according to any one of claims 11 to 13, wherein the openings (8, 80, 88) of the chambers (7) of the hollow body (3, 30, 33) open into the inlet region (45, 65) of the nozzle (41, 61) and are selectably connected with the nozzle (41, 61).
15. The device for cooling a roll (2) or a metal strip (20) according to any one of claims 11 to 14, wherein the cooling shell (40, 60) extends over at least a part of the width and/or the circumference (U) of the roll (2) or extends over at least a part of the width of the metal strip (20) in the width direction (B) and/or the length of the metal strip (20) in rolling direction (W).

Images