RU2826646C2 - Metal material retention system during metal casting - Google Patents

Abstract

FIELD: foundry.

SUBSTANCE: system (1) for containing at least partially liquid metal material from lateral spreading on the open end side of the passage, formed between two casting elements of casting machine, comprises device (2) for supply of at least one compressed gas. Device (2) is equipped with hollow end element (3) with at least one chamber installed near the open end side of the passage. Element (3) comprises blowing surface with holes for blowing compressed gas or gases from said chamber into lateral containment zone. Two or more blowing surfaces are not in one plane or in one blowing surface there are two or more groups of holes, each of which is oriented differently from other groups, for different orientation of gas flow.

EFFECT: increased area of lateral restraint is provided at elimination of direct contact of metal with device of lateral restraint.

18 cl, 14 dwg

Description

Field of technology to which the invention relates

The present invention relates to a system for holding liquid or semi-liquid metallic material, such as aluminum, zinc, magnesium or any metallic alloy, during casting of preferably flat metallic articles, such as strips, according to a technology called twin-roll casting or other alternative casting technologies in which two casting elements are used to create a flat metallic article.

State of the art

Twin-roll casting technology is a well-known technology used since the mid-20th century to produce solid metal semi-finished products starting from liquid material. This technology is mainly used to produce flat strips, but it can be applied to long products such as bars, blanks, etc., because it allows for increased productivity for thin products (up to 10 mm thick or in diameter) and because such shapes can be cast at high speed using twin-roll casting compared to other technologies. Another advantage of twin-roll casting is that the shape of thin and small semi-finished products matches the shape of the finished product, which reduces the amount of molding work (rolling, drawing) in subsequent processes and allows for a finished product that is cheap and can be produced in large quantities.

Two-roll casting can be used with different materials, such as ferrous and non-ferrous alloys, or pure metals.

In a standard steel casting arrangement, twin-roll casting is performed on a twin-roll stand with cooled horizontal rolls arranged parallel and next to each other, with their axes on a common horizontal plane, in which two cooled horizontal rolls for casting aluminum, magnesium, zinc and/or their alloys are arranged one above the other, for example, with their axes on a common vertical plane or on a common plane that is inclined relative to the vertical. The space defined by the casting rolls is fed by a pusher, which feeds the liquid metal material that contacts the cooled rolls to initiate solidification. When feeding and holding the material, the pusher works with the support of side barriers that prevent the lateral flow of the liquid or semi-liquid material until it has completely solidified and which can be part of the pusher itself or separate units. In general, the pusher has a system of channels and chambers that vary depending on the materials to be cast and its features. Typically, the liquid material is supplied by gravity or pumping means, and the channels are made of a material that has insulating properties to prevent temperature drop and unwanted localized curing of the material, and sufficient mechanical resistance to ensure structural integrity and chemical compatibility with the alloy in the liquid state.

One of the most critical problems in metal strip casting is lateral flow of liquid material, which is caused by edge operating conditions and curing parameters.

Typically, with increased casting load, the liquid flow conditions and low casting speed can cause priority cooling of the strip edge, which causes partial lateral strip spreading, increased dimensional control and reduced risk of leakage. However, this results in deterioration of local strip quality and the need for side trimming of the strip.

The operating conditions can be modified to achieve more uniform casting conditions even on the sides, but this can lead to the risk of increased lateral leakage of liquid material, which sticks to the casting roll and causes damage to the equipment, causing the process to be stopped. This can be avoided by improving (using side barriers) the lateral retention of the strip before solidification, but there are technical limitations to achieving these results.

Indeed, mechanical lateral containment systems or mechanical barriers must not be made of materials that can react with the liquid material coming from the casting device and, if they are made of insulating materials, they cannot effectively contain the material. In addition, such materials must not provide excessive resistance to the rolls in order to avoid sliding damage to the rolls due to accidental contact. Usually, to meet these requirements, such materials are soft, for example, oxide refractories. In addition, when reducing the casting load, it is also necessary to ensure effective lateral containment at points that are quite far from the exit of the pusher, in a position near the exit of the interroll gap, that is, at the point of minimum distance between the casting rolls, and this requires the use of very long and very thin lateral barriers. The previously mentioned materials do not allow the required geometry of the lateral barrier to be achieved or to work with the required geometry without the barrier itself spreading or damage to the surface of the roll. By using alternative materials such as steel or metals to create side barriers, the effect of gluing the liquid metal material such as aluminum or its alloys is achieved, in addition to the rapid wear caused by chemical reactions, corrosion and/or abrasion, so there is a risk of damaging the surface of the casting rolls.

Thus, it is necessary to create a containment system that will overcome these shortcomings.

Disclosure of invention

The aim of the present invention is to create a system for lateral containment of liquid metal material, in particular aluminum or magnesium or zinc or a metal alloy based on one of these metals, when casting preferably flat metal products, wherein such a system is designed with the possibility of improving the performance in terms of containing the liquid metal material under any casting load and increasing the area of lateral containment, while eliminating direct contact of the lateral containment device with the liquid metal material.

The system according to the present invention can be used for casting carried out using twin-roll casting technology or according to alternative casting technologies in which two casting elements are used to define the shape of a flat metal product.

Another object of the present invention is to provide a containment system that is flexible, allowing metal products of varying thickness to be cast without the need to replace casting elements.

The present invention achieves at least one of these objects, and other objects that will become apparent in light of the present description, by a system for containing at least partially liquid metallic material at the open end of a passage defined by two casting members, such system comprising a device for supplying at least one compressed gaseous substance,

wherein said feed device is provided with a hollow end element designed to be installed next to said open end of the passage,

wherein said hollow end element defines at least one chamber therein, and said feed device is configured to feed at least one compressed gaseous substance into said at least one chamber,

wherein said hollow end member has at least one surface for purging said at least one compressed gaseous substance from said at least one chamber into a lateral containment zone for said at least partially liquid metallic material,

wherein said at least one blowing surface has several through holes;

and in which two or more purging surfaces that are not in the same plane are provided for different orientation of the flow of said at least one gaseous substance, or one purging surface is provided in which two or more groups of through holes are provided, each of which is oriented differently from the other groups.

Another invention relates to a casting machine for casting metallic materials, which comprises:

- two casting elements defining a passage having two open ends for the solidification of liquid metal material supplied into the space between said casting elements and forming the final product;

- a first containment system described above, installed near the first open end of said passage;

- preferably a second containment system as described above is provided, installed near the second open end of said passage;

wherein preferably the two casting elements are counter-rotating rolls, or belts, or tracks, or combinations thereof.

The invention also relates to a method for casting metal products produced by the said casting machine, wherein the method provides for the following steps:

- supply liquid metal material into the space between two casting elements;

- hardening of the metal material is performed and the product is obtained in the passage between two casting elements;

wherein the lateral containment of the liquid metallic material is performed at least at one of the two open ends of the passage by means of the first containment system;

wherein the lateral containment of the liquid metallic material is performed by feeding at least one compressed gaseous substance into at least one chamber of the said hollow end element, which, using at least one blowing surface, blows the said at least one compressed gaseous substance from at least one chamber towards the lateral containment zone of the said liquid metallic material;

preferably in which the first lateral containment of the liquid metallic material is performed at the first open end of the passage by means of said first containment system, and the second lateral containment of the liquid metallic material is performed at the second open end of the passage by means of said second containment system.

In this description, the twin-roll casting technology is given as an example, in which counter-rotating rolls are used as casting elements.

The solution according to the present invention consists in creating a barrier comprising a compressed gaseous substance, designed to restrain the edge of a flat metal article, for example a strip, during the solidification process by applying a force to said edge in such a way as to press the liquid metal article towards the middle of the strip and to avoid lateral spreading or leakage of molten material.

The principle of the invention is based on the use of a device for feeding at least one compressed gaseous substance, which may be partially shaped in such a way that it can be located very close to the rollers of the casting machine on the side where the material enters the rollers, or on the side where the material exits the rollers, as well as on the sides of the rollers. Such a feeding device is designed with the possibility of blowing at least one compressed gaseous substance, for example air or an inert gas, into the space between the rollers, from one side towards the center. Such a compressed gaseous substance has a double effect of cooling the liquid material at the edge of the strip, which locally accelerates the solidification, and mechanical restraint in order to prevent the liquid material from spreading.

This solution has many advantages.

Firstly, mechanical action is applied and contact between the liquid metal material and any other material is eliminated, therefore any chemical reaction, corrosion or wear is excluded.

More specifically, the solution according to the present invention does not provide for any direct contact between the hollow end element and any surface of the casting rolls or between the hollow end element and the liquid metallic material.

In particular, a distance different from zero is always provided between the hollow end element and any surface of the casting rolls when the hollow end element is located entirely outside the casting rolls and when it is at least partially inserted between said casting rolls, for example due to its wedge shape.

At least one blowing surface of the hollow end member restrains the metallic material solely by blowing a compressed gaseous substance without its contact with the curing material in order to prevent lateral flow of the material from the rolls.

Another advantage is that the containment can be performed at a point between the rolls, which in the solutions known from the prior art cannot be achieved by using any physical barrier due to the limited space. For example, air or inert gas jets can be directed towards the middle of the roll gap, also for very small casting thicknesses. In this case, a physical barrier cannot be arranged between the rolls very close to the roll gap due to the limited clearance provided by the final thickness of the cast product, for example, a strip.

Finally, a significant advantage of the blow-off is the ability to seal any gap between the rolls, even in the event of a change in the position of the roll, without the need for adjustment. For example, the solution according to the present invention continues to work in the case of position control by software and sudden changes in load due to casting conditions, which can cause periodic displacements of the rolls.

The containment system according to the present invention allows to create more concentrated or scattered jets according to its geometry in order to distribute the containment by adjusting it according to the working conditions and reducing the consumption of air or inert gas. In addition, the pressure and mechanical thrust of the injected gas can be adjusted to compensate for different metallostatic pressure of the molten material.

The pneumatic system or side barrier according to the present invention also makes it possible to meet the following requirements:

- lateral containment of metal material under high pressure, for example, a column of liquid metal up to 100-120 mm;

- the lateral containment area can have different lengths, for example, 45-70 mm (back pressure);

- the system is universal and provides different lengths of the cast strip without the need to replace the casting rolls with other rolls of a different length.

Other features and advantages of the invention will become more apparent in connection with the detailed description of non-exhaustive examples of implementation.

The dependent claims of the invention describe specific embodiments of the invention.

Brief description of the drawings

The description of the invention is given with reference to the figures presented as a non-exhaustive example, namely:

Figure 1 shows a view of a horizontal casting machine with lateral containment systems in accordance with the present invention;

Figure 2 shows a perspective view of a system in accordance with the present invention;

Figure 3 shows a section of the casting machine and the solidification section;

Figure 4 shows a perspective view of the system node of Figure 2;

Figure 5 shows a side view of a variant of the said unit inserted between two casting rolls;

Figure 6 shows a cross-section of the unit according to Figure 5;

Figure 7 shows a side view of another embodiment of the said element;

Figure 8 shows a side view of another embodiment of the said element;

Figure 9 shows a side view of another embodiment of the said element;

Figure 10 shows a side view of another embodiment of the said element;

Figure 11 shows a side view of another embodiment of the said element;

Figure 12 shows a side view of another embodiment of the said element;

Figure 13 shows a side view of another embodiment of the said element;

Figure 14 shows a side view of another embodiment of the said element.

Identical elements or nodes have the same reference numbers on the figures.

Implementation of the invention

The containment system according to the present invention can be used for casting carried out using twin-roll casting technology or according to alternative casting technologies in which two casting elements are used to define the shape of a flat metal product.

For example, such an alternative casting technology could be one of the following:

- single-roll casting, in which a flat metal product is solidified by contact with a single, water-cooled rotating roll, starting from a space defined by said roll and a pusher nozzle, such as a pouring device; in this case, the two casting elements are the single roll and said nozzle;

- casting with two belts or two tracks (two-block casting), in which a flat metal product is solidified in a passage between two belts or tracks rotating in different directions, respectively.

- combined casting with rollers and belts, rollers and tracks, or belts and tracks.

In this detailed description, the twin-roll casting technology is used as an example, in which counter-rotating rolls are used as casting elements.

Figure 1 shows an example of a horizontal casting machine with two horizontal casting rolls 20, 21, located one above the other, whose axes lie on a common vertical plane, wherein said machine comprises a pair of restraint systems 1, 1' in accordance with the present invention. However, the systems in accordance with the present invention can also be used in casting machines, whose axes of the two rolls lie on a common plane, which is inclined relative to the vertical. In particular, it is possible to use a vertical casting machine with two casting rolls installed parallel next to each other, whose axes lie on a common horizontal plane.

In the embodiments shown in Figures 1 and 2, a casting machine for casting flat metal products, such as strips, preferably made of aluminum, zinc, magnesium or their alloys comprises:

- two counter-rotating and combined casting rolls 20, 21, defining an outlet for the metal material, having two open end ends, for hardening the liquid metal material and obtaining a flat product;

- means for feeding liquid metal material into the space between two casting rolls to a passage defined by the two casting rolls;

- a first containment system 1 installed near the first open end of the passage;

- preferably a second containment system 1’ installed near the second open end of said passage.

It is sufficient to use one containment system if it is necessary to contain liquid metal material from the side only from one of the two side ends of the specified passage.

The means of delivery, which are known in themselves, contain:

- a pouring device 34 for collecting liquid metal material, for example, coming from an inlet channel (not shown);

- a pusher 35, preferably made of a ceramic material, for feeding liquid metal material coming from the casting device 34 into a passage limited by two casting rollers 20, 21.

Moving means (not shown) for moving the first containment system 1 and/or the second containment system 1’ may be provided for adjusting the distance from each other in a direction parallel to the plane containing the axes of rotation of the two casting rolls 20, 21. Such moving means may be linear drives, such as hydraulic, pneumatic, mechanical drives, combinations thereof, and the like.

This allows casting metal products of different lengths, such as strips, without the need to change the casting rolls. To change from one strip size to another, it is only necessary to move at least one of the two lateral restraint systems 1, 1' relative to the casting rolls 20, 21 along the specified direction. This also applies in the case of using a single restraint system.

Therefore, with a fixed equal width of the casting rolls, the lateral restraint system can be moved in such a way as to set a different width of the cast strip, and therefore there is no need to use a separate set of rolls as in the solutions known from the prior art, when the restraint system cannot be moved laterally, and therefore it is necessary to change the casting rolls each time when casting strips of different widths.

The containment systems 1, 1’ in Figure 1 are installed on the side where the metallic material (liquid metal) enters the space between two casting rolls 20, 21; while Figure 2 shows one containment system 1, which is installed on the side where the metallic material (liquid metal) exits the casting rolls 20, 21. The direction of feed of the metallic material is indicated by arrow F in Figure 2.

In another embodiment of the invention, one or two containment systems may be provided on the input side of the metal material and on the output side of the metal material.

In all embodiments of the invention, each lateral system 1, 1’ for containing the cast material from the corresponding open end side of the passage defined between two casting rollers 20, 21 comprises (Figure 2) a device 2 for feeding at least one compressed gaseous substance, having a hollow end element 3, designed with the possibility of being installed next to the said open end side of the passage defined by the casting rollers 20, 21.

The hollow end element 3 may at least partially have a wedge shape so that it can be inserted at least partially between two casting rolls on the open side of the passage.

As an alternative to the wedge shape, the hollow end element 3 may have the shape of a rectangular or pyramidal parallelepiped or any other shape designed to accommodate said hollow element next to a passage defined between two casting rolls, wherein said hollow element 3 may be at least partially inserted between the two casting rolls at the open end of the passage.

In the example shown in the figures, the hollow end element 3 has the shape of a wedge.

Preferably, each feed device 2 and the corresponding end element 3 are arranged longitudinally and in an external position, for example in a completely external position, relative to the area occupied by the pusher 35.

The hollow end element 3 defines at least one chamber 4 in it, for example a single chamber, as shown in the embodiment in figure 6, which is not limiting. In other embodiments, two to six chambers may be provided. However, embodiments with a number of chambers greater than (and even significantly greater than) six are not excluded, for example if the chambers correspond to the porosity of the material from which the hollow element 3 is made.

The feeding device 2 is designed to feed at least one compressed gaseous substance, such as air or an inert gas, inside at least one chamber 4.

Preferably, the hollow end element 3 has at least one surface for blowing compressed gaseous substance from the at least one chamber 4 into a lateral containment zone for the metal material cast between the casting rollers 20, 21.

As shown in the non-limiting embodiment of Figure 2, each restraint system 1 can be mounted at its first end on a stop 23 of the lower casting roll 21, and provided with a support lever 24 supporting a corresponding hollow end element 3 at the second end of the system, opposite the first end.

The means 40 for moving the hollow end element 3 of one of the two restraint systems 1, 1’ can be provided for regulating the distance from each other in a direction parallel to the plane containing the axes of rotation of the two casting rolls 20, 21.

For example, for each containment system 1, 1’ one means of movement 40 is provided.

In particular, the moving means 40 is designed with the possibility of moving the support lever 24 of the hollow end element 3 in a direction parallel to the plane containing the axes of rotation of the two casting rollers 20, 21.

Such means 40 of movement, for example, can be a linear drive, including a hydraulic, pneumatic or mechanical drive. Preferably, at least one purging surface has several through holes communicating with at least one chamber 4, or is made of a porous binding material for ejecting jets of air or inert gas.

In all embodiments of the invention, the hollow end element 3 comprises a first outer surface 10, which can be directed toward the lateral containment zone and comprises at least one purging surface.

Preferably, the hollow end element 3 also comprises:

- a second outer surface 11, opposite the first surface 10, preferably comprising at least one inlet opening 5 for at least one compressed gaseous substance,

- a third outer surface 8 and a fourth outer surface 9, opposite to each other and connecting the first surface 10 with the second surface 11.

In a non-exhaustive example, the hollow end element 3 at least partially has a wedge shape that is suitable for insertion between two casting rolls. The third outer surface 8 and the fourth outer surface 9 define the wedge shape of the hollow end element 3 (Figures 7 to 14).

The third surface 8 and the fourth surface 9 can be flat or curved, or partially flat and partially curved, and converge in the central plane Z of the hollow element 3, defining the shape of the wedge.

In the case of curved or partially curved surfaces 8 and 9, the radius of their curvature is practically equal to the outer radius of the corresponding casting roll.

As an example, during operation of the containment system according to the invention, the minimum distance between the hollow end element 3 and the casting rollers 20, 21, which is the minimum distance between the surfaces 8, 9 and the corresponding casting roller, is approximately 0.5 to 2 mm, for example about 1 mm. Preferably, the distance between the hollow end element 3 and the edge of the liquid metal material is approximately 8 to 12 mm, for example 10 mm.

According to the embodiment of the hollow end element 3, at least one inlet opening 5 can be provided in the fifth surface 16 (Figure 4), which is removed from the pointed end 25 of the wedge shape, and which connects the first surface 10 with the second surface 11 and the third surface 8 with the fourth surface 9.

In the example in Figures 4 and 5, the third surface 8 and the fourth surface 9, which define the shape of the wedge, are curved and also have a flat part 8', 9', located at the fifth surface 16. At least one inlet opening for at least one chamber 4 can also (or exclusively) be provided in the flat part 8' and/or in the flat part 9'. The flat parts 8' and 9' can also not be provided; in this case, the third surface 8 and the fourth surface 9 are completely curved and define the shape of the wedge of the hollow end element 3.

Preferably, the third surface 8 and the fourth surface 9 are installed symmetrically to the central plane Z of the hollow element 3.

Preferably, in all embodiments of the invention, the hollow end element 3 can be made in the form of a non-detachable element using a 3D printer, preferably from one of the following materials: graphite, calcium silicate, copper, bronze.

Alternatively, the hollow end element 3 may be made of several elements, each made of different materials.

For example, a part or element comprising at least one blowing surface, or parts or elements comprising a corresponding blowing surface, may be made of a porous binder, such as sintered bronze or foam ceramics, or may be defined by a woven metal thread, or in which the said binder is obtained using additive technology.

Preferably, but not necessarily, the supply device 2 may be a pneumatic device or a device capable of compressing and supplying a gaseous substance.

In the first embodiment of the hollow end element 3, the first surface 10 has two or more blowing surfaces that are in different planes relative to each other, for different orientation of the gaseous substance flow towards the containment zone. Such a configuration allows blowing air or inert gas streams in at least two directions and therefore towards at least two different zones of the space enclosed between two casting rolls, for improved lateral containment of the liquid metal material and/or extension of the containment zone.

For example, the through holes of each blowing surface are mutually parallel or inclined at an angle different from zero relative to the through holes of other blowing surfaces.

Preferably, a series of chambers 4 may be provided inside the hollow end element 3, the number of which is equal to the number of blowing surfaces, wherein each chamber supplies material to the corresponding blowing surface.

In the embodiments of the invention shown in Figures 5, 6, 7, 8, 9 and 11 of this first embodiment, the hollow end element 3 has the shape of a wedge, but, as indicated above, said hollow element may have other shapes.

The first variant of the said first embodiment shown in Figure 5 has blowing surfaces 6, 7 on the first surface 10.

The blowing surface 6 defines the X plane, and the blowing surface 7, which is preferably located next to the blowing surface 6, defines the Y plane, which is at an angle to the X plane.

The blowing surface 6 is removed from the pointed end 25 of the hollow end element 3, and the blowing surface 7 is located next to this pointed end.

For example, the blowing surface 6 is flat and has a rectangular shape, preferably elongated, while the blowing surface 7 is flat and has a triangular shape, preferably in the shape of an isosceles triangle, while the base of the isosceles triangle is preferably located near one of the two smaller sides of the rectangular shape of the blowing surface 6.

The central plane Z divides the two blowing surfaces 6, 7 into two equal parts.

When the containment system is installed on the open side of the passage defined between two casting rolls 20, 21 rotating in different directions, the blowing surface 6 is installed perpendicular to the plane of feeding the metal material, and the blowing surface 7 has a first end, which is located near the blowing surface 6 and the lateral containment zone, and a second end, which is removed from the blowing surface 6 and the said lateral containment zone.

In other words, when the blowing surface 7 approaches the inter-roll gap, it deviates relative to the central plane of the casting rolls, which is perpendicular to the plane containing both axes of rotation of the said casting rolls. Therefore, taking into account the direction of feeding the metal material, the blowing surface 7 deviates relative to the edge of the metal material entering between the casting rolls, if the system is installed on the side where the material enters between the rolls, or converges relative to the edge of the metal material exiting the casting rolls, if the system is installed on the side where the material exits the rolls. The blowing surface 6 is mainly parallel to the said edge. Such an embodiment makes it possible to blow air or inert gas jets directed toward the edge of the material, as well as toward the inner zone located near the inter-roll gap, in the space between two casting rolls, for increased lateral containment in the zone, which is not achieved by mechanical barriers known from the prior art.

In the example in Figure 5, the blowing surface 6 has several through holes 14, while the blowing surface 7 has several through holes 15.

The through holes 14 can be mutually parallel and inclined relative to the mutually parallel through holes 15, for example, at an acute angle, preferably between 5° and 45°, more preferably between 10° and 35°. Arrows A and B in Figure 6 show the direction of the jets emerging from the through holes 14 and 15, respectively.

As an alternative to through holes, the surfaces 6, 7 of the purge can be made of a porous binding material.

The second variant of the specified embodiment, shown in Figure 7, provides for a first surface 10 having four purging surfaces 6, 7, 12 located in different planes for different orientation of the flow of gaseous substance into the containment zone.

In addition to the two blowing surfaces 6, 7 according to the first embodiment, according to the second embodiment, two side blowing surfaces 12 are provided next to the blowing surface 6, installed symmetrically to the central plane Z of the hollow end element 3, which divides the blowing surface 6 and the blowing surface 7 into two equal parts.

If the containment surface is mounted on the open end of a passage defined between two casting rolls, the two blowing surfaces 12 have a corresponding first end located near the blowing surface 6, but at a distance from the lateral containment zone, relative to their corresponding second end, which is removed from the blowing surface 6, but located near the lateral containment zone.

In other words, each blowing surface 12 defines a corresponding plane, located at an angle next to the plane X of the blowing surface 6 and, starting from the plane X, deviating relative to the central plane Z, for blowing additional jets of air or inert gas, which converge, for example, both from above or from below in the case of a horizontal casting machine, to the plane of feeding the metal material, in particular to the edge of the metal material in the casting stage to increase the lateral containment of the liquid metal.

In particular, the side surfaces 12 of the blowing and the central surface 6 of the blowing define the groove of the first surface 10.

As an example, the blowing surfaces 12 are flat and rectangular or trapezoidal in shape, preferably having the shape of a rectangular trapezoid, wherein the largest base of the rectangular trapezoid is preferably located near one of the two large sides of the rectangular shape of the blowing surface 6.

In the example of implementation in Figure 7, the blowing surface 6 has several through holes 14, the blowing surface 7 has several through holes 15, and two blowing surfaces 12 have several through holes 17.

The through holes 14 can be mutually parallel and inclined relative to the mutually parallel through holes 15, for example, at an acute angle, preferably between 5° and 45°, more preferably between 10° and 35°.

The through holes 17 can be mutually parallel and inclined relative to the through holes 14, for example, at an acute angle, preferably between 5° and 45°, more preferably between 10° and 35°. However, the axes of the through holes 17 of the blowing surfaces 12 are inclined relative to the axes of the through holes 15 of the blowing surface 7.

As an alternative to through holes, the blowing surfaces 6, 7, 12 can be made of a porous binding material.

The third variant of the specified embodiment, shown in Figure 8, provides for a first surface 10 having four purging surfaces 6, 7, 13 located in different planes for different orientation of the flow of gaseous substance into the containment zone.

In addition to the two blowing surfaces 6, 7 according to the first embodiment, the third embodiment provides for two lateral blowing surfaces 13 next to the blowing surface 7, installed symmetrically to the central plane Z of the hollow end element 3, which divides the blowing surface 6 and the blowing surface 7 into two equal parts.

If the containment surface is mounted on the open end of a passage defined between two casting rolls, the two blowing surfaces 13 have a corresponding first end located near the blowing surface 7 and with the lateral containment zone, relative to their corresponding second end, which is removed from the blowing surface 7 and from the lateral containment zone.

In other words, each blowing surface 13 defines a corresponding plane, located at an angle and next to the plane Y of the blowing surface 7 and, starting from the plane Y, deviating relative to the central plane Z, in such a way that the two blowing surfaces 13 are directed, one to the casting roll 20, and the other to the casting roll 21, and therefore they are not directed to the plane of feeding the metal material. This makes it possible to blow additional streams of air or inert gas directed to the casting roll 20 and the casting roll 21 in such a way that these casting rolls retain air in the space between them, defining a zone with increased pressure in front of the edge of the cast product, which reduces the spreading of the liquid metal near the inter-roll gap.

As an example, the blowing surfaces 13 are flat and rectangular or trapezoidal in shape, wherein preferably the smallest base of the trapezoid is located near one of the two equal sides of the isosceles triangle of the blowing surface 7.

In the example in Figure 8, the blowing surface 6 has several through holes 14, the blowing surface 7 has several through holes 15, and the two blowing surfaces 13 have several through holes 18.

The through holes 14 can be mutually parallel and inclined relative to the mutually parallel through holes 15, for example, at an acute angle, preferably between 5° and 45°, more preferably between 10° and 35°.

The through holes 18 can be mutually parallel and inclined relative to the through holes 15, for example, at an acute angle, preferably between 5° and 45°, more preferably between 10° and 35°.

Preferably, the axes of the through holes 18 of the blowing surfaces 13 are inclined relative to the axes of the through holes 14 of the blowing surface 6.

As an alternative to through holes, the blowing surfaces 6, 7, 13 can be made of a porous binding material.

The fourth variant of the specified embodiment, shown in Figure 9, provides for a first surface 10 equipped with six purging surfaces 6, 7, 12, 13 located in different planes for different orientation of the flow of gaseous substance into the containment zone.

In addition to the two blowing surfaces 6, 7 of the first variant, this fourth variant provides for two additional blowing surfaces 13, provided in the third variant, and two additional blowing surfaces 12, provided in the second variant.

The fifth variant of the specified embodiment, shown in Figure 11, has a first surface 10 having three purging surfaces 6’, 12’ located in different planes for different orientation of the flow of gaseous substance into the containment zone.

The central surface 6 of the blowdown defines the first plane X, and two side surfaces 12’ of the blowdown are located next to the surface 6 of the blowdown and are installed symmetrically to the central plane Z of the hollow end element 3, which divides the surface 6 of the blowdown into two equal parts.

If the containment surface is mounted at the open end of a passage defined between two casting rolls, the two blowing surfaces 12' have a corresponding first end located near the blowing surface 6, but at a distance from the lateral containment zone, relative to their corresponding second end, which is removed from the first blowing surface 6', but located near the lateral containment zone.

In other words, each blowing surface 12' defines a corresponding plane, located at an angle next to the plane X of the blowing surface 6' and, starting from the plane X, deviating relative to the central plane Z, for blowing additional jets of air or inert gas, which converge, for example, both from above or from below in the case of a horizontal casting machine, to the plane of feeding the metal material, in particular to the edge of the metal material during the casting stage to increase the lateral containment of the liquid metal.

In particular, the side surfaces 12’ of the blowing and the central surface 6’ of the blowing define a groove of the first surface 10.

For example, the central surface 6' of the blowing is flat and triangular, preferably has the shape of an isosceles triangle, and the surface 12' of the blowing is flat and rectangular or trapezoidal, with its side located next to one of the equal sides of the isosceles triangle of the surface 6' of the blowing.

In the example in Figure 11, the 6' blowing surface has several through holes 14', while the 12' blowing surface has several through holes 17'.

The through holes 17' of each side surface 12' of the purge can be mutually parallel and inclined relative to the through holes 14', for example, at an acute angle, preferably between 5° and 45°, more preferably between 10° and 35°.

As an alternative to through holes, the surfaces 6’, 12’ of the purge can be made of a porous binder material.

In the second embodiment of the hollow end element 3, the first surface 10 has one blowing surface, in which two or more groups of through holes are provided, preferably of different sizes, each group being differently oriented relative to the other groups for different orientation of the gaseous substance flow into the containment zone. Such an embodiment allows blowing air or inert gas streams directed toward the edge of the material in at least two directions and therefore toward at least two different zones of the space enclosed between two casting rolls for improved lateral containment of the liquid metal material and lengthening the containment zone.

For example, the through holes of each blowing group are mutually parallel or inclined at an angle different from zero relative to the through holes of other groups.

Preferably, one, two or more than two chambers 4 are provided inside the hollow end element 3.

In the embodiments of the invention shown in Figures 10, 12, 13 and 14 of this second embodiment, the hollow end element 3 has the shape of a wedge, but, as indicated above, said hollow element may have other shapes.

The first variant of said second embodiment shown in Figure 10 has one blowing surface 6 on the first surface 10, wherein the blowing surface is preferably formed in a recess of said first surface 10.

The central surface 6 of the blowdown is flat or curved.

When the containment surface is mounted on the open side of a passage defined between two counter-rotating casting rolls, the blowing surface 6, if it is flat, is located perpendicular to the plane of feeding the metal material.

In the case of a curved surface, as it approaches the inter-roll gap, it deviates relative to the central plane of the casting rolls, which is perpendicular to the plane containing both axes of rotation of the said casting rolls. Therefore, taking into account the direction of feeding the metal material, the blowing surface 6 deviates relative to the edge of the metal material entering between the casting rolls, if the system is installed on the side where the material enters between the rolls, or converges relative to the edge of the metal material exiting the casting rolls, if the system is installed on the side where the material exits the rolls. Such an embodiment makes it possible to blow air or inert gas jets directed toward the edge of the material, as well as toward the inner zone located near the inter-roll gap, in the space between two casting rolls, for increased lateral containment in the zone, which is not achieved by mechanical barriers known from the prior art.

In the example in Figure 10, the blowing surface 6 is triangular and has a vertex at the pointed end 25 of the wedge-shaped hollow end element 3.

The central plane Z divides the blowing surface 6 into two equal parts.

In the example in Figure 10, the blowing surface 6 has several through holes 14.

Two or more groups of through holes 14 may be provided, for example, of different sizes, wherein each group has a different orientation or inclination compared to the other groups for a different orientation of the gaseous substance flow to the containment zone. Thus, differently oriented air or inert gas jets can be obtained similarly to the jets obtained using different variants of the first embodiment, in which two or more blowing surfaces are provided.

The second variant of the said second embodiment, shown in Figure 12, is identical to the variant in Figure 10, except that it has a blowing surface 6 with a substantially triangular shape and a preferably rounded apex located at a distance from the pointed end 25 of the wedge-shaped hollow end element 3.

According to the third and fourth variants of the said second embodiment, shown in Figures 13 and 14, respectively, a completely flat or curved first surface 10 is provided, which coincides with the only blowing surface.

Surface 10 has two or more groups of through holes, preferably of different sizes, each group being oriented differently relative to the other groups for different orientation of the flow of gaseous substance into the containment zone.

For example, two or more groups of through holes may be provided, each group having a different orientation or inclination relative to the other groups for different orientation of air or inert gas jets similar to the jets obtained using different variants of the first embodiment, which provides two or more blowing surfaces.

In the example in Figure 13, the through holes are distributed differently on the surface 10, but exclusively in the central zone of the surface 10. In particular, the through holes can be divided into six groups, corresponding to the through holes 14, 15, 17, 18 of the variant according to Figure 9, which provides for six blowing surfaces.

In the example in Figure 14, the through holes 14 are distributed differently, but generally over the entire surface 10.

In all embodiments indicated above (Figures 5-14), the through holes can be arranged in the form of honeycombs on one or more blowing surfaces, i.e. with the distribution of through holes in rows with an indent. Preferably, the density of holes on the surface 10 of the hollow end element 3 is made in such a way that the total surface area on the surface 10 is from 50% to 70% of the surface area of 10.

The process of solidification of liquid metal material using a casting machine is shown in Figures 1-3. In this process, products, such as strips or sheets, are directly cast from liquid metallic material through a pusher 35 between two cooled and counter-rotating casting rolls 20, 21. A cross-section of the solidification region is shown in Figure 3. As soon as the liquid metallic material touches the rolls 20, 21, a hard shell begins to form, which increases as it moves toward the outlet pass 38. The hard shell, adhered to the upper roll 20 and the lower roll 21, reaches a solidification point 36 just before the outlet pass 38 (typically the total solidification length is from 10 to 20 mm in a standard casting process at a casting speed of 1.2 m/min and a metal sheet thickness of 5 mm), and there the metal product is deformed by the casting rolls 20, 21, resulting in a casting product 37.

The containment system according to the present invention in one of its embodiments can be used, in particular, for moving liquid metal or liquid metal alloy by applying pressure along the depth 39 of the crucible (Figure 3, according to the actual solidification length) during casting. This pressure, which is created exclusively by air or inert gas supplied by the supply device 2, controls the position of the lateral edge of the metal material in the area between the pusher 35 and the outlet passage 38, where there is no real physical containment.

The containment system according to the present invention can also be used after the exit pass 38 to contain the liquid metal material still present at the exit from the casting rolls.

Claims (31)

1. A system (1) for containing at least partially liquid metallic material from lateral spreading on an open end face of a passage formed between two casting elements of a casting machine, comprising a device (2) for feeding at least one compressed gaseous substance, provided with a hollow end element (3) designed with the possibility of being installed near the open end face of said passage, wherein at least one chamber (4) is formed in said hollow end element (3), wherein said device (2) for feeding is designed with the possibility of feeding at least one compressed gaseous substance into said at least one chamber (4), wherein said hollow end element (3) comprises at least one purging surface (6, 7) in which through holes (14, 15) are made, ensuring the purging of at least one compressed gaseous substance from said at least one chamber (4) into the lateral containment zone of said at least partially liquid metallic material, wherein two or more surfaces (6, 7, 6’, 12’) of the purge are not located in the same plane, ensuring different orientation of the flow of the at least one gaseous substance, or two or more groups of through holes are made in one blowing surface, each of which is oriented differently from the other groups. 2. The system according to item 1, characterized in that when one or more surfaces (6, 7, 6’, 12’) of the blowdown are not located in the same plane, the through holes of each blowdown surface are made mutually parallel and inclined at an angle different from zero relative to the through holes of the other blowdown surfaces, or when making one blowing surface with two or more groups of through holes, the through holes of each blowing group are made mutually parallel or inclined at an angle different from zero relative to the through holes of other groups. 3. The system according to claim 1 or 2, characterized in that said hollow end element (3) has at least a partially wedge-shaped form, allowing it to be installed between two casting elements. 4. The system according to one of claims 1-3, characterized in that said hollow end element (3) comprises at least one first outer surface (10) facing the lateral containment zone and comprising at least one purging surface (6, 7), and, preferably, said hollow end element (3) also comprises: a second outer surface (11) opposite said first surface (10), a third outer surface (8) and a fourth outer surface (9), opposite to each other and connecting the first surface (10) with the second surface (11). 5. The system according to item 4, characterized in that said third outer surface (8) and said fourth outer surface (9) form a wedge-shaped hollow end element (3). 6. The system according to one of claims 1-5, characterized in that it comprises a first blowing surface (6) defining a first plane X, and a second blowing surface (7) defining a second plane Y located at an angle to the first plane X, wherein when said containment system is installed on the open end side of said passage, the first blowing surface (6) is located perpendicular to the plane of supply of liquid metal material, and the second blowing surface (7) comprises a first end located near the first blowing surface (6) and the lateral containment zone, and a second end located at a distance from the first blowing surface (6) and said lateral containment zone. 7. The system according to item 6, characterized in that the said hollow end element (3) is made with a central plane perpendicular to plane X, and the said system comprises two thirds of the blowing surfaces (12) next to the first blowing surface (6), located symmetrically to the said central plane, and when the said system is installed on the open end of the said passage, the corresponding first ends of the third blowdown surfaces (12) are located near the first blowdown surface (6), but at a distance from the lateral containment zone relative to their corresponding second ends, which are located at a distance from the first blowdown surface (6), but near the lateral containment zone. 8. The system according to item 6 or 7, characterized in that the said hollow end element (3) is made with a central plane perpendicular to plane X, and the said system contains two additional blowing surfaces (13) next to the second blowing surface (7), located symmetrically to the said central plane, and when installing the said system on the open end of the said passage, the corresponding first ends of the additional surfaces (13) are located next to the second surface (7) of the purge and with the lateral containment zone relative to their corresponding second ends, which are located at a distance from the surface (7) of the purge and the lateral containment zone. 9. The system according to one of paragraphs 1-8, characterized in that said hollow end element (3) is made in the form of a single element, preferably from a material selected from the following materials: graphite, calcium silicate, copper, bronze. 10. A casting machine for casting metallic materials, comprising: two casting elements (20, 21) defining a passage having two open end ends, designed with the possibility of solidifying a liquid metallic material supplied into the space between said casting elements, with the formation of a final product, a first containment system (1) according to one of paragraphs 1-9, installed near the first open end of said passage. 11. A casting machine according to claim 10, which comprises a second containment system (1’) according to one of claims 1-9, installed near the second open end of said passage. 12. A casting machine according to claim 10 or 11, characterized in that the two casting elements (20, 21) are made in the form of two casting rolls located one above the other, the axes of rotation of which are located in a common plane, and, preferably, the said metallic material is aluminum, or magnesium, or zinc, or a metal alloy based on one of the said metals. 13. A casting machine according to claim 11 or 12, characterized in that it comprises means (40) for moving the hollow end element (3) of the first containment system (1) and/or the hollow end element (3) of the second containment system (1’), designed with the possibility of adjusting the distance between said containment systems (1, 1’) in a direction parallel to the plane in which the axes of rotation of the two casting rolls (20, 21) are located. 14. A casting machine according to one of claims 11-13, characterized in that the hollow end element (3) of the first containment system (1) and, preferably, the hollow end element (3) of the second containment system (1’) have at least a partially wedge-shaped form, ensuring the possibility of installing the hollow end element (3) between two casting rolls (20, 21). 15. A casting machine according to item 14, characterized in that between the hollow end element (3) and any surface of the casting rolls (20, 21) a distance different from zero is provided when the hollow end element (3) is installed completely outside the casting rolls and when the hollow end element (3) is installed between the said casting rolls (20, 21) due to its wedge shape. 16. A method for casting metallic materials, carried out using a casting machine according to paragraph 12 or 13, comprising the following steps: feeding liquid metal material into the space between two casting elements (20, 21), solidification of the metallic material to obtain an article, carried out in a passage formed between two casting elements (20, 21), while lateral containment of the liquid metallic material is carried out on at least one of the two open end faces of said passage using a first containment system (1), wherein the lateral containment of the liquid metallic material is ensured by feeding at least one compressed gaseous substance into at least one chamber (4) of the said hollow end element (3) of the feeding device (2), designed with the possibility of feeding, by means of at least one purging surface (6, 7), the said at least one compressed gaseous substance from at least one chamber (4), towards the zone of lateral containment of the said liquid metallic material. 17. The method according to claim 16, characterized in that the first lateral containment of the liquid metal material is carried out on the first open end side of said passage using the first containment system (1), and the second lateral containment of the liquid metal material is carried out on the second open end side of said passage using the second containment system (1’). 18. The casting method according to claim 16 or 17, characterized in that the effect of lateral containment of the metallic material is carried out only by blowing a compressed gaseous substance through at least one blowing surface (6, 7, 6’, 12’), without contact of said at least one blowing surface (6, 7, 6’, 12’) with the hardening metallic material.