EP3444038A1 - Injection device and method for cooling a metallic strand in a continuous casting machine - Google Patents

Abstract

The invention relates to a spray apparatus (10, 60) for cooling a metallic strand in a continuous casting machine, in which at least one multi-nozzle head (16) and at least one switching valve (26, 28, 30) are provided, the multi-nozzle head having at least a first and a second A nozzle (46, 48, 50), wherein the switching valve is disposed upstream of the multi-nozzle head, wherein the switching valve is in flow communication with all the second nozzles in the multi-nozzle head to release a supply of spray liquid to all the second nozzle or lock.

Description

The invention relates to a spray gun and a method for cooling a metallic strand in a continuous casting machine.

From the European patent EP 2 714 304 B1 a method for cooling a metallic strand in a continuous casting machine is known in which a spray jet is applied to a metallic strand by means of a plurality of spray nozzles. In order to be able to vary an amount of spray liquid in the widest possible range, the spray nozzles are designed for a maximum amount of water to be applied and, in order to reduce the spray liquid quantity, intermittently acted upon by switching valves. For setting a predetermined amount of spray liquid, which is below a maximum dispensable spray liquid quantity, thus the spray nozzles are permanently operated intermittently. Due to the intermittent action on the metallic strand, its cooling does not necessarily take place continuously.

With the invention, a spray gun and a method for cooling a metallic strand in a continuous casting machine are to be improved.

According to the invention, a spray apparatus for cooling a metallic strand in a continuous casting machine is provided, in which at least one multi-nozzle head and at least one switching valve are provided, wherein the multi-nozzle head has at least a first and a second nozzle and wherein the switching valve is arranged upstream of the multi-nozzle head, wherein the Switching valve is in fluid communication with all the second nozzles in the multi-nozzle head, to enable or block a supply of spray liquid to all the second nozzle. Preferably, a plurality of multi-nozzle heads are provided and the multi-nozzle heads are spatially spaced from each other.

In the spray gun according to the invention thus a variation of the dispensed spray liquid quantity is achieved by switching on or off of nozzles in the multi-nozzle heads. In the case of a predetermined and constant amount of spray liquid, however, there is no intermittent admission, but a permanent admission of the selected nozzles with the selected spray liquid pressure. Thereby, a continuous operation of the nozzle and thus a continuous cooling of the metallic strand can be achieved. The nozzles in the multi-nozzle head are designed and arranged so that each nozzle alone and any combination of nozzles each cause a uniform spray liquid distribution over the width of the metallic strand and thus a homogeneous cooling of the strand. This is achieved inter alia by overlapping the spray jets of the nozzles. The switching valves can be designed, for example, as pneumatic switching valves and, for example, controlled by the amount of pressure of a supplied compressed air. For example, if in each case three nozzles are present in the multi-nozzle heads, the then existing two or three switching valves can then be designed so that at a first pressure, for example 6 bar, only the first nozzles are supplied with spray liquid. If the pressure of the supplied compressed air is then lowered, for example to 3 bar, the switching valves open not only for the first nozzles but also for the second nozzles, so that spray liquid is then discharged from the first nozzles and the second nozzles. If the pressure of the supplied compressed air is further reduced, for example to 0 bar, all three switching valves open, so that spray liquid is then discharged through the first nozzles, through the second nozzles and the third nozzles in the multi-nozzle heads. Alternatively, a control of the switching valves can also be carried out electrically or electronically, for example by using solenoid valves as switching valves. Also possible is a combination of switching valves, which are designed as compressed air valves, with solenoid valves, which then selectively apply the switching valves with compressed air to change their switching state. A great advantage of the spray gun according to the invention is that the amount of spray liquid dispensed can be varied within a very wide range and yet a continuous dispensing of the spray liquid takes place. Also, by simply replacing nozzle inserts in the multi-nozzle heads, the dispensed spray liquid quantities can be varied. A variation of the dispensed spray liquid quantity can then take place on the one hand via the pressure of the supplied spray liquid and on the other via the connection or disconnection of individual nozzles in the multi-nozzle heads. As a result, a very large variation range of the amount of spray liquid of, for example, 1:15 can be achieved. The first nozzle can be permanently supplied with spray liquid or the first nozzle can also be assigned a switching valve. The switching valves can be designed so that nozzles in which the spray water supply is shut off, permanently or partially flushed with compressed air, to prevent deposits and contamination in nozzles and pipes. The switching valves can be provided for this purpose with a branch for the compressed air and optionally a throttle for the compressed air in the branch. Each multi-nozzle head may be provided with one or more switching valves or multiple multi-nozzle heads are associated with one or more switching valves.

In a further development of the invention, each multi-nozzle head has n nozzles, wherein all the second nozzles and optionally all third, fourth to n-th nozzles are each in flow communication with a switching valve to supply a spray liquid to all second nozzles and optionally all third, fourth to nth nozzles to release or lock, where n is a natural number and has a value between 2 and 10.

The number of nozzles in the multi-nozzle heads is in principle arbitrary, where n advantageously equal to 3, so that in each multi-nozzle nozzle three nozzles are present and a first switching valve all first nozzles, a second switching valve all second nozzles and a third switching valve all third nozzles assigned. Particularly advantageous values for n are between 2 and 10. The first switching valve can be omitted if the first nozzles are to be permanently supplied with spray liquid.

In a further development of the invention, at least a first pipe and a second pipe for supplying spray liquid are provided, wherein the first pipe is connected to all first nozzles and the second pipe to all second nozzles. The first switching valve may be upstream of the multi-nozzle heads on the first pipeline and the second switching valve may be provided upstream of the multi-nozzle heads on the second pipeline.

By providing pipelines and supplying all the first nozzles in the multi-nozzle heads via a common first pipeline and supplying all the second nozzles in the multi-nozzle heads via a common second pipeline, a very space-saving design of the spray apparatus according to the invention can be achieved. In continuous casting machines, the nozzles for cooling a metallic strand usually have to be arranged between support rollers for the metallic strand, so that there is usually very little space for the arrangement of the nozzles available. Another significant advantage of common piping is that only one single switching valve needs to be assigned to each pipeline. The design effort can be significantly reduced. The first pipe can be permanently supplied with spray liquid, so that can be omitted in this case, the first switching valve. If n nozzles are provided in each multi-nozzle head, there are also n pipelines, wherein in each case one pipeline is assigned to all first, second, third and n-th nozzles.

In a further development of the invention, a switching valve is provided upstream of the multi-nozzle heads on the second pipeline and optionally on the third, fourth to n-th pipeline, wherein a n is a natural number and has a value between 2 and 10. Also on the first pipe upstream of the multiple nozzle heads, a switching valve may be provided.

For example, n = 3, so that three pipes and three nozzles are provided in all multi-nozzle heads. At least two of the three lines is in each case assigned a switching valve, so that a spray liquid supply through the first pipe is either permanently released or shut off or released by the first switching valve, a spray liquid supply can be shut off or released by the second pipe through the second switching valve and a spray liquid supply can be shut off or released by the third pipe by means of the third switching valve. If a switching valve is present in the first pipeline, all first nozzles in the multi-nozzle heads can thus be switched on or off together, as can all second nozzles or all third nozzles in the multi-nozzle heads. Particularly advantageous values for n are between 2 and 10.

In a further development of the invention, the nozzles of at least one multi-nozzle head are different in that they each output a different amount of spray liquid at a predefined pressure of the spray liquid.

By such staggering of the nozzle sizes in the multi-nozzle heads, an even wider spreading of the spray liquid quantity than with identical nozzles can be achieved, which can be output with the spray gun according to the invention.

In a further development of the invention, the nozzles of a multi-nozzle head with respect to the dispensed spray liquid quantity are coordinated so that the first nozzle within a predefined pressure range between a low pressure and a high pressure of the spray liquid dispenses a spray liquid within a first amount range and that the amount range of the sum the amount of spray liquid discharged from the first nozzle and the second nozzle between the low pressure and the high pressure overlaps the first amount range.

In this way, a very large area of the amount of spray liquid can be covered without it being possible to cover or output certain values in this area. In other words, the second tonnage area defined by the spray liquid amount output from the first nozzle and the second nozzle in common between the low pressure and the high pressure overlaps the first tonnage area at least at the high pressure.

In a further development of the invention, each multi-nozzle nozzle n nozzles, where appropriate, the first to third nozzle, the first to fourth nozzle or the first to n-th nozzle within a predefined pressure range between a low pressure and a high pressure of the spray liquid a spray liquid within a output the third, fourth or nth quantity range and the quantity ranges overlap.

Also in this case n is advantageously equal to 3, with further advantageous values of n lying between 2 and 10. The second quantity range and the third quantity range thus overlap, as do the third and fourth or (n-1) th and n-th quantity ranges.

In a further development of the invention, the multi-nozzle heads are arranged spatially spaced from each other along the pipes.

In this way, a compact, space-saving design of the spray gun according to the invention can be achieved. Advantageously, the pipes run parallel to each other. To the nozzles of the multi-nozzle heads then only short stubs of the parallel pipelines are required.

In a further development of the invention, the pipelines run parallel to a casting direction of the continuous casting machine and the multiple nozzle heads are arranged one behind the other along the pipelines in the casting direction.

If several, arranged in the casting direction juxtaposed spray guns according to the invention are provided, a variation of the width can be achieved by switching off individual spray guns, which is acted upon by the spray guns according to the invention, according to the just cast strand width of the metallic strand.

In a further development of the invention, the pipes are arranged transversely to a casting direction of the continuous casting machine and the multiple nozzle heads are arranged transversely to the casting direction behind the other along the pipes.

Depending on the intended application, it may also be advantageous to install the pipes transversely to the casting direction. With a casting direction while a feed direction of the metallic strand is meant.

In a further development of the invention, the switching valves are designed as compressed air valves and each switching valve is associated with a solenoid valve for enabling or shutting off a compressed air supply to a respective switching valve.

In this way, a constructive at first glance seemingly consuming arrangement can be achieved, but which is very reliable. Compressed air valves can reliably perform their function even in harsh environmental conditions. Solenoid valves, on the other hand, can be easily controlled electronically and can also be integrated into a higher-level process control in a simple manner. The combination of electronically actuated solenoid valves with compressed air valves therefore ensures a problem-free and very reliable version of the spray gun according to the invention.

In a further development of the invention, a plurality of solenoid valves are combined in a solenoid valve island, wherein the solenoid valve island has a common base and a common electronic control for the solenoid valves.

In this way, a compact structure can be achieved. The solenoid valve island or the common electronic control of the solenoid valve island may be suitable for connection to a data bus, so that a very simple electronic wiring can be achieved.

In a further development of the invention, at least one of the pipes is formed as a profile with at least one continuous hollow chamber in the longitudinal direction of the profile.

For example, an extruded or extruded profile can be used, which consists for example of aluminum, brass or steel, especially stainless steel. In this way, the pipelines can be made very stable and, for example, the profiles can already provide mounting options for the multi-nozzle heads.

In a further development of the invention a plurality of pipes are formed by means of a profile with a plurality of longitudinally continuous hollow chambers.

In this way, a very compact embodiment of the spray gun according to the invention can be achieved.

In a further development of the invention several profiles are connected to a carrier.

In a further development of the invention, the multi-nozzle heads are arranged on the profile or on the carrier having a plurality of profiles.

The pipelines can be formed by forming a carrier thereby simultaneously as mechanically bearing parts.

The problem underlying the invention is also solved by a method for cooling a metallic strand in a continuous casting machine having a spraying device according to the invention, wherein the steps of releasing a spraying liquid supply and / or switching off a spraying liquid supply to all first nozzles, all second nozzles and / or all n-th nozzles of the multi-nozzle heads are provided in response to a required amount of spray liquid, wherein the release and / or shutdown of the spray liquid supply is carried out exclusively with a change in the required spray liquid quantity.

Thus, with the method according to the invention, a very large variation of the amount of spray liquid dispensed by the nozzles can be achieved, while at the same time a constant application of liquid spray quantity of the metallic strand with spray liquid and thus also a continuous cooling is achieved. Only with a change in the amount of spray liquid then individual nozzles can be switched on or off.

Fig. 1

eine schematische Darstellung eines erfindungsgemäßen Spritzapparats gemäß einer ersten Ausführungsform,

Fig. 2

eine schematische Darstellung einer Mehrfachdüseneinheit mit Mehrfachdüsenkopf der Spritzvorrichtung der Fig. 1,

Fig. 3

ein Diagramm zur Erläuterung des mit der Spritzvorrichtung der Fig. 1 abdeckbaren Bereichs an ausgegebener Spritzflüssigkeitsmenge,

Fig. 4

eine schematische Darstellung eines Profils zur Ausbildung mehrerer Rohrleitungen bei dem erfindungsgemäßen Spritzapparat, und

Fig. 5

eine schematische Darstellung eines erfindungsgemäßen Spritzapparats gemäß einer zweiten Ausführungsform.

Further features and advantages of the invention will become apparent from the claims and the following description of preferred embodiments of the invention in conjunction with the drawings. Individual features of the different embodiments of the invention shown in the drawings and described in the description can be combined with one another in any desired manner without going beyond the scope of the invention. This also applies to a combination of individual features without further features, with which the individual features are described or shown in connection. In the drawings show:

Fig. 1

a schematic representation of a spray apparatus according to the invention according to a first embodiment,

Fig. 2

a schematic representation of a multi-nozzle unit with multiple nozzle head of the spray device of Fig. 1 .

Fig. 3

a diagram for explaining the with the spray device of Fig. 1 coverable range of dispensed spray liquid quantity,

Fig. 4

a schematic representation of a profile for forming a plurality of pipes in the spray gun according to the invention, and

Fig. 5

a schematic representation of a spray apparatus according to the invention according to a second embodiment.

The presentation of the Fig. 1 shows a spray gun 10 according to the invention, which is intended for the arrangement in a continuous casting machine, in which a metallic strand is produced. A casting direction of the metallic strand is shown by an arrow 12. The casting direction 12 corresponds to the feed direction of the metallic strand. For example, the metallic strand of liquid steel is poured and then transported between support rollers in the direction of the arrow 12. The spray gun according to the invention is then arranged above the metallic strand, a further spray gun 10 according to the invention can be arranged below the metallic strand in order to be able to cool it from the top side and the bottom side. A plurality of spray devices 10 according to the invention can be arranged next to one another in order, for example, to be able to cool even very wide metallic strands over their entire surface.

The spray apparatus 10 according to the invention has a nozzle carrier 14 which extends parallel to the casting direction 12. At this nozzle carrier 14 a plurality of multi-nozzle units 16 are arranged, which in the Fig. 2 will be explained in more detail. In the illustrated embodiment, a total of five multi-nozzle units 16 are arranged on the nozzle carrier 14. In this case, three multiple nozzle units 16 are arranged on the right side of the nozzle carrier 14 and two multiple nozzle units 16 on the left side of the nozzle carrier 14 , This arrangement is merely exemplary and can be chosen essentially arbitrarily. The multi-nozzle units 16 may be permanently connected to the carrier 14 or releasably connected to the carrier 14.

The nozzle carrier 14 is arranged in a continuous casting machine above the support rollers for the metallic strand. The multiple nozzle units 16 then extend downwardly from the nozzle carrier 14, into Fig. 1 So into the drawing level, so that the Spray nozzles can then be arranged for example between the support rollers for the metallic strand.

In the nozzle carrier 14, a first pipe 18 a, a second pipe 20 a and a third pipe 22 a are provided which extend parallel to each other and parallel to the nozzle carrier 14. The first pipe 18a is shown by a solid line, the second pipe 20a by a broken line, and the third pipe 22a by a dot-dash line. This is for illustrative purposes only and to distinguish the three pipes 18a, 20a, 22a.

Each multi-nozzle unit 16 has three spray nozzles, which are each acted upon by separate nozzle water pipes. To do this in the schematic representation of Fig. 1 to show, three nozzle water pipes 18b, 20b and 22b are shown in each multi-nozzle unit 16. The nozzle water pipes 18b of all multi-nozzle units 16 are connected via short branch lines to the pipe 18a. The nozzle water pipes 20b of all the multi-nozzle units 16 are connected to the second pipe 20a via short stubs, and the nozzle water pipes 22b of all the multi-nozzle units 16 are connected to the third pipe 22a via short stubs. In a suitable structural design of the pipes 18a, 20a, 22a and the carrier 14, the stubs can be omitted.

Upstream of the multi-nozzle units 16, a nozzle valve block 24 is provided with a total of three switching valves 26, 28 and 30. The first switching valve 26 is connected to the first pipe 18a, the second switching valve 28 is connected to the second pipe 20a, and the third switching valve 30 is connected to the third pipe 22a. By means of the three switching valves 26, 28, 30, a spray liquid supply, for example, a water supply, which is symbolized by an arrow 32, are released or shut off to the pipes 18a, 20a, 22a. The switching valves 26, 28, 30 are advantageously designed as pneumatically actuated pinch valves. A pneumatic control of the switching valves 26, 28, 30 takes place by means of a respective solenoid valve, which are arranged in a solenoid valve island 34, which is shown above the nozzle valve block 24. This solenoid valve island 34 is, as symbolized by an arrow 36, supplied compressed air. In addition, the solenoid valve island 34 has a common electronic control that can be connected to a data bus. Such a data bus and thus the supply of electrical signals is symbolized by means of an arrow 38. In the context of the invention, the first switching valve 26 can be omitted if the first pipe 18a and thus all the first nozzles of the multi-nozzle units 16 are to be permanently supplied with spray liquid. A higher-level device for switching on and off the spray water supply for the entire spray gun 10 may of course still be provided.

Depending on how the solenoid valves are actuated in the solenoid valve island 34, they release a compressed air supply to the switching valves 26, 28, 30 or block the compressed air supply, and as a result, a spray liquid supply to the pipes 18a, 20a, 22a is either released or blocked.

Fig. 2 shows a schematic representation of a multi-nozzle unit 16. Each multi-nozzle unit 16 has a mounting block 40, in each of which the beginning of the nozzle water pipes 18b, 20b and 22b is arranged. The nozzle water pipes 18b, 20b, 22b then lead through a carrier 42 to a multi-nozzle head 44. In this multi-nozzle head 44, three nozzles 46, 48, 50 are provided, each having a in Fig. 2 can produce schematically indicated spray. If all three nozzles 46, 48, 50 are in operation, then the spray jets of the nozzles 46, 48, 50 overlap. Regardless of whether only one of the nozzles 46, 48, 50 is in operation or any combinations of the nozzles 46, 48, 50 in operation, a homogeneous spray liquid distribution and a homogeneous cooling over the entire width of the metallic strand is always achieved. With the mounting block 40, the multi-nozzle unit 16 is permanently or detachably connected to the carrier 14.

The multi-nozzle head 44 is designed so compact that it can be arranged between two support rollers for the metallic strand. In any case, the multi-nozzle head 44 is formed and arranged so that the spray jets generated by the nozzles 46, 48, 50 can pass unhindered between the support rollers.

The first nozzle 46 is supplied with spraying liquid by means of the first nozzle water pipe 18b, the second nozzle 48 is supplied with spraying liquid by means of the second nozzle water pipe 20b, and the third nozzle 50 is supplied with spraying liquid by means of the third nozzle water pipe 22b. Ultimately, therefore, all the first nozzles 46 in the multi-nozzle units 16 are in fluid communication with the first pipe 18a, but all the first nozzles 46 are not in flow communication with the second pipe 20a and the third pipe 22a. In the same way, all the second nozzles 48 of the multi-nozzle units 16 are exclusively in flow communication with the second pipe 20a. All third nozzles 50 of the multi-nozzle units 16 are exclusively in flow communication with the third pipe 22a.

By means of the first switching valve 26 can thus be released or shut off a spray liquid supply to all first nozzles 46 in the multi-nozzle units 16. By means of the second switching valve 28, a spray liquid supply to all second nozzles 48 in the multi-nozzle units 16 can be enabled or shut off. By means of the third switching valve 30, a spray liquid supply to all third nozzles 50 of the multi-nozzle units 16 can be released or shut off.

Thus, if only a comparatively small amount of spray liquid is required to cool a metallic strand, only the nozzles permanently supplied with spray liquid are used or there is a higher-level control not shown, for example via the switching valve 26, a spray liquid supply into the first pipe 18a free, whereas a spray liquid supply into the second pipe 20a and the third pipe 22a by means of the switching valves 28, 30 is blocked. As a result, only the first nozzles 46 will discharge a spray. The output of the spray through the first nozzle 46 is carried out continuously and without interruption. Only when the required amount of spray liquid changes, on the one hand, by means not shown, a pressure of the supplied spray liquid can be changed. On the other hand, all second nozzles 48 can be connected via the second switching valve 28, for example. If even more spray liquid is required, all third nozzles 50 can be switched on, for example via the third switching valve 30.

A change in the amount of spray liquid dispensed can thus take place, on the one hand, by a change in the pressure of the supplied spray liquid, on the other hand by switching on or off the nozzles 46, 48, 50. At a constant predetermined amount of spray liquid, the nozzles 46, 48, 50 produce a continuous and not interrupted spray. As a result, cooling of the metallic strand can also be continuous and without interruption.

The first nozzles 46, the second nozzles 48 and the third nozzles 50 in each multi-nozzle head 44 may be identical or designed so that they spend a different spray liquid quantity at the same spray liquid pressure. For example, the first nozzle 46 outputs a first spray liquid quantity at a predetermined spray liquid pressure, the second nozzle 48 outputs a larger spray liquid volume at the same spray liquid pressure, and the third nozzle 50 dispenses an even larger spray liquid quantity at the same spray liquid pressure.

In this way, the spread region of the dispensable spray liquid quantity compared to three identically designed nozzles 46, 48, 50 can be significantly increased.

The nozzles 46, 48, 50 may be formed in the multi-nozzle block 44, for example, as nozzle inserts, so that these nozzle inserts can be changed quickly and easily. This is advantageous if the nozzles 46, 48, 50 must be replaced because of wear, but also to adjust the amount of spray liquid dispensed.

Fig. 3 represents a diagram in which the dispensed spray liquid quantity in liters per minute is plotted against the water pressure of the spray liquid. A first lined line shows the amount of spray liquid dispensed by the first nozzles 46 above the water pressure. A second, cross-lined line shows the sum of the amount of spray liquid dispensed by the first nozzle 46 and the second nozzle 48. A third squared line shows the sum of the amount of spray liquid dispensed by all three nozzles 46, 48, 50.

It can be seen that the first nozzle 46 at a spray liquid pressure of 1 bar, a spray liquid quantity of only about 1 l / min outputs. At a spray liquid pressure of 12 bar then a spray liquid amount of about 3 l / min is output.

If the output amount of spray liquid is increased above 3 l / min, the second nozzle 48 is switched on. At the same time the spray liquid pressure is reduced again to 1 bar.

It can be seen from the cross-lined line that the sum of the amount of spray liquid dispensed by the first nozzle 46 and the second nozzle 48 at 1 bar spray liquid pressure is about 2 l / min. This value is thus lower than the amount of spray liquid dispensed by the first nozzle 46 alone at a spray liquid pressure of 12 bar. The amount ranges of the spray liquid discharged from the first nozzle 46 alone and the spray liquid amount output from the first nozzle 46 and the second nozzle 48 thus overlap. This makes it possible to achieve a very precise adjustment of the dispensed spray liquid quantity by varying the spray liquid pressure and by switching on or off individual nozzles 46, 48, 50.

At a spray liquid pressure of 12 bar, the first nozzle 46 and the second nozzle 48 together give about 7.5 l / min of spray liquid, as can be seen on the right-hand side with the cross-hatched line. Should then increase the spray liquid quantity even further are all three nozzles 46, 48, 50 supplied with spray liquid and at the same time the spray liquid pressure is reduced back to 1 bar. As indicated by the squares line in Fig. 3 can be seen, all three nozzles 46, 48, 50 together at a spray liquid pressure of 1 bar, a spray liquid amount of about 6 l / min. Here, too, the quantity ranges of the spray liquid quantity jointly dispensed by the first nozzle 46 and the second nozzle 48 overlap, and the spray liquid quantity jointly dispensed by all three nozzles 46, 48, 50. Of course, an increase in the amount of spray liquid can be done not only in the manner described, but it can be switched on or off at other spray liquid pressures nozzle to within the diagram of Fig. 3 to be able to set the desired amount of spray agent.

The nozzles 46, 48, 50 of the multi-nozzle heads 44 are so coordinated with respect to the dispensed spray liquid quantity that the first nozzle within a predefined pressure range between a low pressure and a high pressure of the spray liquid dispenses a spray liquid quantity within a first amount range, and the sum of the amount of spray liquid discharged from the first nozzle and the second nozzle at the low pressure is lower than the amount of the spray liquid discharged from the first nozzle at the high pressure. The quantitative ranges of the first nozzle, on the one hand, and the spray fluid quantity dispensed jointly by the first nozzle and the second nozzle, on the other hand, thus overlap. In an analogous manner, this is also the case for the sum of the spraying liquid quantity dispensed from the first nozzle and the second nozzle at the high pressure and the sum of the spraying liquid quantity discharged from the first nozzle, the second nozzle and the third nozzle together at low pressure. This is based on the in Fig. 3 to recognize with squares provided line. This tuning of the dispensed spray liquid quantity can be achieved both with three identical nozzles 46, 48, 50 and with three different nozzles 46, 48, 50 with respect to the dispensed spray liquid quantity.

Fig. 4 schematically shows the carrier 14 of Fig. 1 in a front view. The carrier 14 is formed by a profile 52 having three longitudinally continuous hollow chambers. These three hollow chambers form the pipes 18a, 20a and 22a, to which, as has been explained, the branch lines to the multi-nozzle units 16 or directly the multi-nozzle unit 16 are connected.

Laterally of the three hollow chambers or pipes 18a, 20a, 22a are still undercut grooves 54, 56 are arranged. These undercut grooves 54, 56 can be used for mounting, for example, the multi-nozzle units 16 on the carrier 14. The Carrier 42 of the Fig. 2 , which combines the three nozzle water pipes 18b, 20b, 22b may be formed in the same or similar manner as a profile 52 having a plurality of hollow chambers.

Fig. 5 shows a schematic representation of a spray device 60 according to the invention according to another embodiment.

The spray gun 60 has a multi-nozzle unit 16, as already described with reference to the Fig. 2 has been described. The multi-nozzle unit 16 will therefore not be described again.

In contrast to the multi-nozzle unit 16 of Fig. 2 On the mounting block 40 of the multi-nozzle unit 16, a nozzle valve block 24 with a total of three switching valves 26, 28 and 30 is arranged, which is already based on the spray device of Fig. 1 was explained.

The first switching valve 26 is associated with a first nozzle water pipe 18b, the second switching valve 28 is associated with a second nozzle water pipe 20b, and the third switching valve 30 is associated with a third nozzle water pipe 22b. Thus, via the switching valves 26, 28, 30, a spray water supply to the nozzle water pipes 18b, 20b, 22b and thus to the nozzles 46, 48 and / or 50 in the multi-nozzle head 44 can be enabled or disabled.

A spray liquid supply to the nozzle valve block 24, a compressed air supply to the nozzle valve block 24 and an optionally superior solenoid valve island are in Fig. 5 for the sake of clarity not shown but in an identical manner as in Fig. 1 provided and related to Fig. 1 described.

The spray gun 60 of the invention Fig. 5 thus has only a multiple nozzle unit 16. Of course, in the context of the invention, but a plurality of spray guns 60 in an arrangement similar to the Fig. 1 be combined. Several sprayers 60 are then provided for cooling a metallic strand. In contrast to the spray gun 10 of Fig. 1 can then, if several spray gun 60 according to Fig. 5 are provided, the individual multi-nozzle units 16 are driven separately from each other.

Claims (16)

A spray gun for cooling a metallic strand in a continuous casting machine, characterized in that at least one multi-nozzle head and at least one switching valve is provided, each multi-nozzle head having at least a first and a second nozzle, wherein the at least one switching valve upstream of the multi-nozzle head is arranged and wherein the switching valve is in fluid communication with all second nozzles in the multi-nozzle head to release or block a supply of spray fluid to all second nozzles. Spray gun according to claim 1, characterized in that a plurality of multi-nozzle heads are provided, wherein the multi-nozzle heads are arranged spatially spaced from each other, Spray gun according to claim 1 or 2, characterized in that each multi-nozzle head has n nozzles, wherein all second nozzles and optionally all third, fourth to n-th nozzles are each in flow communication with a switching valve to supply a spray liquid to all the second nozzles and optionally, to enable or disable all third, fourth and nth nozzles, respectively, where n is a natural number and has a value between 2 and 10. Spray gun according to claim 1, 2 or 3, characterized in that at least a first and a second switching valve are provided, wherein the first switching valve is in flow communication with all the first nozzles in the multi-nozzle heads to release a supply of spray liquid to all the first nozzle or to and wherein the second switching valve is in fluid communication with all second nozzles in the multi-nozzle heads to release or block a supply of spray fluid to all the second nozzles. Spray gun according to one of the preceding claims, characterized in that at least a first pipe and a second pipe for supplying spray liquid are provided, wherein the first pipe is connected to all first nozzles and the second pipe to all the second nozzles. Spray gun according to one of the preceding claims, characterized in that n pipes are provided, wherein the first pipe is connected to all first nozzles, the second pipe is connected to all the second nozzles and optionally, the third, fourth to nth pipes are connected to all third, fourth and n-th nozzles, respectively, where n is a natural number and has a value between 2 and 10. Spray gun according to claim 5 or 6, characterized in that upstream of the multi-nozzle heads on the second pipe and optionally on the third, fourth to n-th pipe each have a switching valve is provided, wherein n is a natural number and has a value between 2 and 10 , Spray gun according to claim 5, 6 or 7, characterized in that upstream of the multi-nozzle heads on the first pipe, a switching valve is provided. Spray gun according to at least one of the preceding claims, characterized in that the nozzles of at least one multi-nozzle head are different in that they each output a different amount of spray liquid at a predefined pressure of the spray liquid. Spray gun according to one of the preceding claims, characterized in that the nozzles of a multi-nozzle head with respect to the dispensed spray liquid quantity are coordinated so that the first nozzle within a predefined pressure range between a low pressure and a high pressure of the spray liquid a spray liquid quantity within a first range and that a second amount range of the sum of the amount of spray liquid discharged from the first nozzle and the second nozzle between the low pressure and the high pressure overlaps the first amount range. Spray gun according to claim 10, characterized in that each multi-nozzle head has n nozzles, where appropriate, the first to third nozzle, the first to fourth nozzle or the first to n-th nozzle within a predefined pressure range between a low pressure and a high pressure of the spray liquid output a spray liquid amount within a third, fourth, and n-th quantity range, respectively, and that the quantity ranges overlap, where n is a natural number and has a value between 2 and 10. Spray gun according to at least one of the preceding claims, characterized in that the switching valves are designed as compressed air valves and that Each switching valve is associated with a solenoid valve for enabling or shutting off a compressed air supply to a respective switching valve. Spray gun according to claim 12, characterized in that a plurality of solenoid valves are combined in a solenoid valve island, wherein the solenoid valve island has a common base and a common electronic control for the solenoid valves. Spray gun according to at least one of the preceding claims, characterized in that at least one of the pipes is formed as a profile with at least one continuous in the longitudinal direction of the profile hollow chamber. A method for cooling a metallic strand in a continuous casting machine by means of a spraying device according to at least one of the preceding claims, comprising the steps of: releasing a spraying liquid supply and / or switching off a spraying liquid supply to all second nozzles and / or all nth nozzles of the multi-nozzle heads in dependence on a required Spritzflüssigkeitsmenge, wherein the release and / or shutdown of the spray liquid supply is made only with a change in the required spray liquid quantity. A method according to claim 15, characterized by releasing a spray liquid supply or switching off a spray liquid supply to all first nozzles of the multi-nozzle heads in dependence on a required spray liquid quantity, wherein the release and / or shutdown of the spray liquid supply is made exclusively with a change in the required spray liquid quantity.

Images