EP1932605B1 - Method and device for manufacturing wide strips made of copper or copper alloys - Google Patents

Abstract

Copper or copper alloys wide strips production involves pouring a molten liquid into a revolving wide strip mold (1). The surface of molten metal in the distribution container (9) is maintained at a constant level above the place, where the pour nozzle (14) is fixed in the distribution container in 75-90 mm range with the level of the bath surface (7) of the mold. The molten metal is guided by an ascending channel (11) from the distribution container to the pour nozzle. An independent claim is also included for a device for producing wide strips of copper or copper alloys.

Description

The invention relates to a method for producing wide strips of copper or copper alloys by casting a liquid melt into a circumferential broadband mold and a device suitable for carrying out the method, consisting of a distributor vessel and a pouring nozzle for supplying the liquid molten metal into the strip casting mold.

To produce wide strips, the liquid melt located in a tundish is directed into the lower-lying broadband mold by means of one or more pouring tubes or pouring nozzles. Devices for feeding a molten metal from a tundish or tundish into a mold are already known in various designs. The melt located in the tundish is introduced by means of a pouring tube or several pouring tubes into the melt bath, the pool, the revolving cast strip mold. The pouring tube may be arranged vertically or at a defined angle, inclined to the horizontal. The casting pipes should ensure a uniform and low-turbulence distribution of the melt in the strip casting mold. A sufficient fill level in the tundish ensures that the pouring tube is completely filled with melt. The flow rate of the melt is influenced by the metallostatic pressure of the melt in the tundish, depending on the casting angle of the pouring tube. With increasing acceleration of the melt in the pouring tube, a negative pressure is generated, which leads to turbulence and Badspiegelschwankungen of located in the pool of the strip casting mold melt.

A variety of the known pouring tubes are dip tubes that dip into the molten bath of the mold and distribute the supplied melt below the bath surface.

From the DE 101 13 206 A1 a dip tube for casting molten metal is known, which has a funnel-shaped expanding swirling chamber to reduce the kinetic energy of the melt at the Tauchrohrauslass. The calmed melt reaches the pool via side outlet openings. The dip tube is arranged vertically and has at the transition from the pipe section to Verwirbelungskammer a spoiler edge.

From the EP 1 506 827 A1 a casting system for a thin slab mold with a tundish and a Tauchgießrohr is known, wherein the flow-tapered dip tube is arranged to extend obliquely downwards. The outlet opening of the dip tube is located below the bath level of the mold. The outflow opening is covered by a lip and arranged so that the melt is deflected several times and distributed transversely to the longitudinal axis of the mold.

The known devices with inclined tundish extending from the tundish into the lower mold die tubes require that the dip tube is fully filled with melt.

These cause inclusions in the flat products to be produced, which have a negative effect on the quality.

From the EP 0 194 327 A1 is a Doppelbandstranggießkokille known. The tundish is connected via a right angle bent intermediate tube with the pouring tube. This consists of a horizontally extending and an upwardly bent portion which opens into the mold, wherein the outlet opening is not immersed in the pool. The melt stream is diverted several times until it enters the mold due to the shiphon arrangement of tundish, intermediate pipe and pouring pipe. In order to avoid that air can enter from outside into the mold space, a special device for regulating the position of the mold level is provided.

In the DE 40 39 959 C1 a casting device is described in which the melt is passed through an obliquely downwardly extending channel from the tundish into the mold, wherein for throttling the flow rate of the melt above the channel, a linear induction motor is arranged. This solution is associated with a lot of effort.

In vertically arranged immersion tubes, it is known to equip them with mechanical throttles in order to improve the filling of the interior of the pouring tube by reducing the flow velocity ( EP 0 950 451 B1 ).

In practice, it has been found that for the production of strips with a width of 800 to 1500 mm and a thickness of 20 to 50 mm by casting a molten copper by means of dip tubes into a broadband mold significant problems occur. Even with a slight inclination of the dip tubes occurs due to the flow rate of the supplied below the bath surface melt to the formation of vortices in the pool, are flushed through the gas bubbles and oxidic and other impurities that accumulate on the surface in the melt. These lead to voids and cracks in the cast structure of the finished strip.

Due to material-specific properties, potting of copper or copper alloys poses special difficulties compared to other non-ferrous metals due to high-temperature intermetallic corrosion and high oxygen affinity.

The invention has for its object to provide a method for producing wide strips of copper or copper alloys by casting a liquid metal melt in a circumferential broadband mold, with which it is possible to achieve a quality-matched cast structure. Furthermore, a device suitable for carrying out the method is to be provided.

According to the invention, the object is achieved by the technical features of claim 1. Advantageous embodiments and further developments of the procedure are the subject of claims 2 to 9. Claim 10 relates to a device suitable for carrying out the method. Advantageous embodiments of the device are subject matter of claims 11 to 20.

The proposed procedure includes the following measures:

The melt level in the tundish is maintained at a constant level (H), above the point of incorporation of the tuyere into the tundish, in a range of 75 to 90 mm, based on the level of the bath level of the mold. The molten metal in the tundish or tundish is passed through an ascending channel from the tundish to the casting nozzle. According to the configuration of the tundish, the ascending channel can be arranged in the corresponding side wall of the tundish. In certain applications, it may be expedient that the melt flows through a parallel to the horizontal channel extending before entering the casting nozzle, which preferably widens in the flow direction in width. When flowing through this channel, a lowering of the flow velocity of the melt can be effected.

The channel cross-section is preferably to be designed such that a ratio of flow rate to volume flow of 1: 4 to 1: 3 and at the exit point of 1: 1.5 to 1: 2 is maintained at the entry point.

After the melt flow into the casting nozzle, it is distributed symmetrically over a width which corresponds to the width of the strip to be produced. The melt is passed within the casting nozzle through at least one first throttle to reduce the kinetic energy of the melt flow. Behind the throttle, a reduced flow rate is established and there is a uniform volume flow extending over the entire width. During the flow through the throttle, the melt is uniformly thermally stressed. As a result, deformations of the casting nozzle due to material stresses can be avoided. The effect of increasing the temperature of the melt has the advantage that continuous casting of the pouring nozzle can be dispensed with during casting.

At the exit point of the casting nozzle, the melt is deflected by a further throttle in the direction of Kokillenbadoberfläche and divided in the vertical direction over the entire bandwidth of the mold into a plurality of small individual streams, which run as a laminar flow to form a wedge-like outlet profile with an extending direction of the tape Opening angle of 15 to 30 ° to the bath level of the mold is entered into the molten bath of the mold.

As a result of the aforementioned measures, after the melt emerges from the outlet throttle, a flow velocity which approximately corresponds to the belt speed of the mold and is below 0.1 m / s is achieved. The melt passes as a laminar flow to form a wedge-shaped outlet profile in the mold. As a result, turbulence in the pool of the mold are largely avoided. Through the outlet profile formed as a melt wedge a uniform heat input is achieved over the entire width of the mold, which has an advantageous effect on the casting quality. The risk of voids and cracks forming in the cast structure is thus considerably reduced. The maximum thickness of the run-out profile extending over the entire width may be variable, but should be at least equal to or less than the thickness of the tape to be cast.

Depending on the respective procedural boundary conditions, such as strip dimensions, casting capacity, composition of the casting melt, the casting nozzle can be arranged differently with respect to the bath level.

The discharge openings of the pouring nozzle can be located above the bath level of the mold. The distance of the outlet throttle pouring nozzle should be at the smallest point to the bath level depending on the thickness of the tape to be cast in a ratio distance / thickness of 1: 1.5 to 1: 1.1. Preferably, the level difference between discharge strip or outlet throttle and bath mirror surface is ≤ 10 mm.

According to a further embodiment, it is provided that the discharge openings of the pouring nozzle partially submerge in the bath level of the mold. In this case, only the front discharge openings of the discharge bar are completely above the bath level. The discharge openings may be arranged in the form of a plurality of rows which extend transversely to the direction of strip travel.

With regard to the material thickness and the cross-sectional areas of the passage openings, the first throttle is designed such that a ratio of outlet cross-sectional area to volume flow of 1: 8 to 1:12 is maintained, the outlet cross-sectional area resulting from the sum of the individual cross-sectional areas of the passage opening of the throttle. Due to the material thickness of the flow and outlet throttle, the flow path length is determined within the throttle, wherein the flow velocity of the melt can be influenced in a targeted manner by flow paths of different lengths.

The casting unit of the device intended for carrying out the method is arranged so that a level difference of 70 to 95 mm exists between the bath level of the mold and the level height. This makes it possible to keep the flow rate of the melt at a low level.

Based on the design of the distribution vessel, the melt is to flow out of the distribution vessel through a rising pouring channel, the inlet opening of which lies in the immediate vicinity of the bottom of the distribution vessel. This ensures that the liquid level in the distribution vessel can be maintained at a low level, whereby the metallostatic pressure is low, and no air is introduced during the outflow of the melt. The rising channel is arranged in the front wall portion of the distribution vessel, which faces towards the mold.

The pouring nozzle has a distributor portion and a discharge portion, wherein the distributor portion widens progressively in its width, up to the width of the belt to be cast. Between the distributor section and the discharge section there is arranged a first throttle with throughflow openings extending over the entire cross-sectional area. These are preferably arranged in a row, either directly adjacent to the bottom portion or at a small distance from the bottom of the casting nozzle.

The discharge section has a snout tapering in the direction of the mold, whose lower boundary extends obliquely upward at a defined angle and is equipped as a discharge strip with openings pointing in the direction of the bath surface. The discharge strip or outlet throttle is arranged at an opening angle of 15 to 30 ° to the bath level of the mold. Preferably, the lowest point of the Austragsleiste is located above the bath surface, at a distance which is 0.9 to 0.5 times the thickness of the pouring Bandes corresponds. Preferably, however, the distance should be kept small and not greater than 10 mm. Due to the short distance, a special "freezing" of the melt is prevented with special copper alloys. In certain applications, it may also be useful if the lowest point of the Austragsleiste is in touching contact with the bath surface or partially immersed in this.

The discharge openings of the discharge bar can be designed and arranged differently according to the flow velocity to be achieved, such as e.g. in the form of rows with identical or different opening cross-sections.

Casting nozzle and distribution vessel can also be connected via an intermediate piece with a pouring channel, which runs parallel to the horizontal and continuously increases in width in the flow direction. The intermediate piece may also be an integral part of the distribution vessel. The intermediary flow path is intended to ensure that the kinetic energy of the flow velocity is already dissipated in this section.

By means of the proposed measures, for example, in the production of an endless belt with a width of 1290 mm and a thickness of 40 mm, corresponding to a casting capacity of about 55 t / h, the present at the outlet of the tundish flow rate of liquid molten metal to about the 10 to 20 times reduced.

The flow velocity of the melt emerging from the casting nozzle can thus be adapted to the belt speed.

The invention will be explained below using an exemplary embodiment.

Fig. 1

die Vorrichtung in vereinfachter schematischer Darstellung als Längsschnitt,

Fig. 2

die Gießeinheit als Draufsicht,

Fig. 3

eine erste Ausführungsvariante der Vorlaufdrossel als Vorderansicht,

Fig. 4

eine zweite Ausführungsvariante der Vorlaufdrossel als Vorderansicht,

Fig. 5

eine dritte Ausführungsvariante der Vorlaufdrossel als Vorderansicht,

Fig. 6

eine erste Ausführungsvariante der Auslaufdrossel als Draufsicht,

Fig. 7

eine zweite Ausführungsvariante der Auslaufdrossel als Draufsicht,

Fig. 8

eine dritte Ausführungsvariante der Auslaufdrossel als Draufsicht und

Fig. 9

einen Ausschnitt der Gießdüse in perspektivischer Darstellung.

In the accompanying drawing show:

Fig. 1

the device in a simplified schematic representation as a longitudinal section,

Fig. 2

the pouring unit as a plan view,

Fig. 3

a first embodiment of the flow throttle as a front view,

Fig. 4

a second embodiment of the flow throttle as a front view,

Fig. 5

a third embodiment of the flow throttle as a front view,

Fig. 6

a first embodiment of the outlet throttle as a plan view,

Fig. 7

a second embodiment of the outlet throttle as a plan view,

Fig. 8

a third embodiment of the outlet throttle as a plan view and

Fig. 9

a section of the pouring nozzle in a perspective view.

The in the FIG. 1 The device shown consists of a broadband mold 1 and a casting unit 8, which are arranged in line. The casting unit 8 is in Fig. 2 shown as a single illustration. The broadband mold 1 consists of an upper circumferential casting belt 2 and a lower circumferential casting belt 3, which form the upper and lower walls of the mold 1. The endless casting belts 2, 3 are guided over deflection rollers, of which in FIG. 1 only the two front pulleys 4 and 5 are indicated by a circular arc. The mold space 6 is bounded on its two longitudinal sides by side walls not shown in detail, by which the width of the belt to be cast is determined. The mold 1 is at an angle of, for example 9 ° inclined to the horizontal. The melt located between the casting belts 2 and 3 is moved in the withdrawal direction and solidified by cooling. The level or bath level in the mold 1 is identified by the reference numeral 7.

The deduction or belt speed of the casting belts 2, 3 depends on the width and

Thickness of the belt to be cast.

The pouring unit 8 for feeding the melt into the mold 1 ( Fig. 2 ) consists of a distributor vessel 9, an intermediate piece 12 and a pouring nozzle 14.

The distribution vessel 9 has in the direction of the mold 1 facing wall portion 10 has a centrally disposed, obliquely upwardly extending pouring channel 11 with a rectangular cross-sectional area. To the distribution vessel 9, the intermediate piece 12 is connected, which has a pouring channel 13. At the connection point of the intermediate piece 12, the pouring channel 13 has the same dimensions as the pouring channel 11 in cross section. Subsequently, the pouring channel 13 widens in its width, as in FIG Fig. 2 you can see. The pouring channel 13 runs parallel to the horizontal or to the bath level 7 of the mold 1. Due to the continuous widening of the cross section of the pouring channel 13 in the direction of the pouring nozzle 14, it acts like a diffuser. At the end of the intermediate piece 12, the pouring nozzle 14 is flanged to this. The casting nozzle 14 is arranged in a slightly downwardly inclined angle, for example of 9 °, and extends up to the level of the bath level 7 of the mold 1. The in the FIGS. 1 . 2 and 9 The pouring nozzle 14 shown is divided into a distributor section 15 and a discharge section 18. The manifold section 15 is designed so that the casting nozzle 14 widens in width, up to the width of the belt to be cast. The height of the channel in the distributor section 15 remains unchanged and corresponds to the height of the pouring channels 11 and 13. The pouring nozzle 14, which is adapted in its width of the bandwidth to be cast, for example, has a length of about 150 to 200 mm. The length of the distributor section is about 60% of the length of the pouring nozzle.

At the end of the distributor section 15, a feed throttle 16 extending over the entire cross section is arranged. The flow restrictor 16 has a certain wall thickness, for example 6 to 8 mm, and arranged near the bottom openings 17. The individual juxtaposed openings or holes 17 have identical cross-sectional areas and equal distances from each other. The sum of the cross-sectional areas of the flow-through openings is e.g. 0.9 to 0.94 times the inlet cross section of the pouring channel 13.

In the FIGS. 3 to 5 Different variants of the flow throttle 16 are shown. The flow throttle 16 according to Fig. 3 has slots 17a. A second embodiment ( Fig. 4 ) is equipped with shortened oblong holes 17b, which extend to the bottom portion 20 of the pouring nozzle 14 and are arranged in the form of a "comb". A third variant ( Fig. 5 ) has circular holes 17c.

The subsequent to the manifold section 15 discharge section 18 has a tapering in the direction of the mold 1 muzzle 19, as in Fig. 1 shown. At the bottom portion 20 is followed by an upwardly angled Austragsleiste 21, which is designed as a discharge throttle and has a certain wall thickness. The inclination or opening angle α of Discharge strip 21 is approximately 15 to 30 °, based on the surface of the bath level 7 of the mold 1. The discharge strip 21 has a plurality of discharge openings 22, along the width of the belt to be cast. In the FIGS. 6 to 8 Different variants of the outlet throttle or discharge bar 21 are shown.

In the Fig. 6 shown dispensing strip 21 has three rows 22a, 22b, 22c at circular discharge openings 22d. The openings within a row are identical. The arranged at the lowest point of the Austragsleiste 21 row 22a has the smallest openings, the subsequent rows 22b and 22c each have larger diameter openings. As the diameter of the openings increases, their number decreases.

The discharge bar according to Fig. 7 has two rows with identical circular outlet openings 22d, which are arranged offset to one another.

In the Fig. 8 shown Austragsleiste has only a number of discharge openings, wherein the identical openings 22 are designed as slots 22e.

The arrangement and design of the discharge openings of the outlet throttle or Austragsleiste is determined on hand special calculation models, taking into account that the average outflow velocity of the melt after leaving the outlet throttle should be less than 0.1 m / s. Preferably, the outlet throttle 21 has a thickness of about 6 to 10 mm and a conical shape extending from the outside to the center to achieve a gradient flow. The outlet openings or bores can be arranged inclined at an angle of 12 to 20 ° counter to the direction of the inflow flow.

• Im Verteilergefäß bzw. Tundish 9 befindet sich die flüssige Schmelze mit einer definierten Füllstandhöhe H. Dabei ist wesentlich, dass während des kontinuierlichen Gießprozesses die Schmelze im Verteilergefäß 9 auf einem konstanten Niveau H gehalten wird, wobei Gießeinheit 8 und Bandkokille 1 so anzuordnen sind, dass zwischen dem Badspiegel 7 der Kokille 1 und
• der Füllstandshöhe H im Verteilergefäß 9 eine Niveaudifferenz N von 75 bis 90 mm eingehalten wird (Fig. 1). Die Füllstandshöhe H im Verteilergefäß 9 liegt demzufolge mindestens in Höhe der Obergrenze des Gießkanals 11 an der Austrittsstelle des Verteilergefäßes 9. Dadurch ist einerseits sichergestellt, dass im Verteilergefäß 9 keine Luft in die Schmelze eingeschleust werden kann. Andererseits wird durch diese Niveaudifferenz eine für den Gießprozess vorteilhafte, nicht zu hohe, Strömungsgeschwindigkeit der Schmelze gewährleistet. Die Strömungsgeschwindigkeit der Schmelze ist direkt proportional der Niveaudifferenz N. Die Schmelze strömt aufgrund des metallostatischen Druckes im Verteilergefäß 9 aufsteigend durch den Gießkanal 11. Dieser ist während des Gießprozesses ständig voll mit Schmelze gefüllt. Die Gießdüse 14 kann auch direkt am Verteilergefäß 9 angeschlossen sein. Bei der in Fig. 1 gezeigten Ausführung des Verteilergefäßes 9 ist es jedoch zweckmäßig, ein Zwischenstück 12 zwischen Tundish 9 und Gießdüse 14 anzuordnen. Wird ein Zwischenstück 12 angeordnet, so ist es vorteilhaft, wenn der Gießkanal 13 in diesem parallel zur Horizontalen verläuft. Der Volumenstrom der Schmelze ist abhängig von den Abmessungen des herzustellenden Bandes, das durch die vorgegebene Gießleistung bestimmt wird. Im vorgesehenen Zwischenstück 12 wird der strangförmige Volumenstrom aufgrund des sich in der Breite erweiternden Gießkanals 13 gleichmäßig verteilt, wobei sich dessen Höhe verringert.

The flow pattern of the liquid copper melt during the casting process is as follows:

• In the distribution vessel or tundish 9 is the liquid melt with a defined level height H. It is essential that during the continuous casting process, the melt in the distribution vessel 9 is kept at a constant level H, casting unit 8 and coil mold 1 are to be arranged so that between the bath level 7 of the mold 1 and
• the level height H in the distribution vessel 9 a level difference N of 75 to 90 mm is maintained ( Fig. 1 ). Consequently, on the one hand, it is ensured that no air can be introduced into the melt in the distributor vessel 9. The fill level H in the distribution vessel 9 is therefore at least equal to the upper limit of the pouring channel 11 at the exit point of the distribution vessel 9. On the other hand, an advantageous, not too high, flow rate of the melt is ensured by this level difference for the casting process. The flow rate of the melt is directly proportional to the level difference N. The melt flows due to the metallostatic pressure in the distribution vessel 9 ascending through the pouring channel 11. This is constantly filled with melt during the casting process. The pouring nozzle 14 may also be connected directly to the distribution vessel 9. At the in Fig. 1 shown embodiment of the distribution vessel 9, however, it is expedient to arrange an intermediate piece 12 between tundish 9 and pouring nozzle 14. If an intermediate piece 12 is arranged, then it is advantageous if the pouring channel 13 runs parallel to the horizontal in this. The volume flow of the melt is dependent on the dimensions of the strip to be produced, the determined by the predetermined casting performance. In the intended intermediate piece 12 of the strand-shaped volume flow is evenly distributed due to the widening in width casting channel 13, wherein the height is reduced.

Depending on the casting performance of the pouring channel 13 should be designed so that at the entry point E of the pouring channel 13, a ratio flow rate to volume flow of 1: 4 to 1: 3 and at the exit point A of 1: 1.5 to 1: 2 becomes ( Fig. 2 ).

After the melt has entered the casting nozzle 14, it is continuously distributed in the distributor section 15 over the entire width of the casting nozzle 14, which corresponds to the width of the strip to be cast. The volume flow is distributed evenly on both sides continuously. In Fig. 9 the melt supply is indicated by an arrow. The inlet cross section S of the pouring nozzle 14 is identical to the outlet cross section A of the intermediate piece 12. The casting nozzle 14 is at its two longitudinal sides (in the flow direction) by means of Fig. 9 not to be seen side walls closed.

At the end of the distributor section 15, a flow throttle 16 with openings 17 is arranged. When flowing through the openings 17, the kinetic energy of the melt flow is reduced and emerging from the throttle 16 partial flows flow at a reduced flow rate and unite to a over the entire width of the discharge section 18 extending even flow.

With regard to the material thickness or depth of the flow throttle 16, by which the flow path length is determined within the throttle, and the size of the cross-sectional areas of the passage openings 17, 17a, 17b, 17c, the flow restrictor should be designed so that a ratio of outlet cross-sectional area to volume flow in the range from 1: 8 to 1:12 is complied with. The outlet cross-sectional area results from the sum of the individual cross-sectional areas of the passage openings 17, 17 a, 17 b, 17 c of the throttle 16.

The flow throttle 16 thus also causes a symmetrical distribution of the melt over the entire width of the discharge section 18 of the pouring nozzle 14, wherein a continuous volume flow sets. When flowing through the flow restrictor 16, the melt is uniformly thermally stressed. As a result, deformations of the casting nozzle 14 due to material stresses are virtually eliminated. The temperature increase of the melt caused by the flow throttle 16 makes it possible to dispense with continuous heating of the casting nozzle 14 during casting. During casting, the discharge section of the pouring nozzle need not be completely filled with melt, but the degree of filling should be at least 50%.

By means of the discharge strip 21, which is arranged inclined in the discharge section 18, with the discharge openings 22, the melt is deflected in the direction of the mold bath level. Through the outflow 22 melt is divided into small vertical streams, which are evenly distributed over the entire bandwidth as a laminar flow. At the same time a further reduction of the flow velocity is effected by the discharge bar. The casting nozzle 14 is arranged so that at least the lowest point of the discharge strip 21 is in direct physical contact with the bath level 7 of the mold 1. Through the opening angle α of the discharge strip 21 is formed between the discharge strip 21 and the bath level 7 a kind of melt wedge as discharge profile. The supplied melt passes as a calm, even flow in the Kokillenbad. The flow velocity of the melt after emerging from the openings 22 of the outlet throttle 21 corresponds approximately to the withdrawal speed of the finished strip.

Due to changes in the material thickness or depth of flow 16 and outlet throttle 21, the flow velocity of the melt can be adapted specifically to the respective production-specific conditions by means of calculations and preliminary tests. By introducing the melt as a laminar flow and forming a melt wedge turbulence in the pool of the mold are largely excluded. Due to the outlet profile formed over the entire width of the mold as melting wedge a uniform heat input is achieved, so that the introduction of liquid metal into the pool has no adverse effect on the casting quality. Due to the reduction in the flow rate of the liquid molten metal and the formation of a wedge-shaped outlet profile, the risk that turbulence in the pool of the mold, almost eliminated. The maximum height of the outlet profile or melting wedge, which is determined by the opening angle α (15 to 30 °) of the discharge strip 21, is dependent on the material thickness of the strip to be cast and should be adjusted so that at the point of the smallest distance to the bath level 7 a ratio distance / band thickness of 1: 1.5 to 1: 1.1 is maintained.

The proposed method and associated apparatus are particularly suitable for the production of copper strips with a width of 1000 to 1300 mm and a thickness of 30 to 50 mm. By means of the proposed measures, it is therefore possible to produce strips of copper or copper alloys which have no voids or cracks which impair the quality.

Claims (20)

1. Method for the production of wide strips of copper or copper alloys by pouring a molten liquid into a revolving wide strip mold (1), with the molten metal guided from the distribution container (9) into the lower wide strip mold (1) by a pour nozzle (14) inclined at an angle in which the surface of molten metal in the distribution container (9) is maintained at a constant level (H) above the place where the pour nozzle (14) is fixed in the distribution container (9) in the range of 75 mm to 90 mm with respect to the level of the bath surface (7) of the mold (1), the molten metal is guided by an ascending channel (11) from the distribution container (9) to the pour nozzle (14) and is distributed within the pour nozzle (14) symmetrically over a width which corresponds to the width of the strip to be produced, with the molten metal within the pour nozzle (14) being guided through at least one first flow restrictor (16) and redirected at the exit point of the pour nozzle (14) through another flow restrictor (21) in the direction of the mold bath surface (7) and separated into numerous small individual flows in a vertical direction over the entire strip width of the mold (1), the individual flows being carried into the molten metal bath of the mold (1) as a laminar flow which forms a wedge-type outflow profile with an opening angle (α), running in the direction of discharge of the strip, of between 15° to 30° to the bath surface (7) of the mold (1).
2. Method according to claim 1, characterized in that the outlets (22, 22d, 22e) of the pour nozzle (14) are located above the bath surface (7) of the mold (1), with the distance of the pour nozzle (14) from the bath surface (7) at the smallest point set at a ratio of distance/thickness of 1:1.5 to 1:1.1, dependent on the thickness of the strip to be poured.
3. Method according to claim1, characterized in that the outlets (22, 22d, 22e) of the pour nozzle (14) are partly immersed in the bath surface (7) of the mold (1).
4. Method according to one of the claims 1 to 3, characterized in that before entering the pour nozzle (14) the molten metal flows through a channel (13) running parallel to the horizontal, which extends in width in the direction of flow.
5. Method according to one of the claims 1 to 4, characterized in that the molten metal in the form of individual flows arranged in the form of rows (22a, 22b, 22c) is discharged from the pour nozzle (14).
6. Method according to one of the claims 1 to 5, characterized in that a ratio of flow rate to volume flow of 1:4 to 1:3 and of 1:1.5 to 12 is maintained at the entry point (E) of the channel (13) and at the exit point (A) of the channel respectively.
7. Method according to one of the claims 1 to 6, characterized in that the first flow restrictor (16) is designed in such a manner as regards the material thickness and the cross sectional areas of the openings (17, 17a, 17b, 17c) that a ratio of outlet cross sectional area to volume flow of 1:8 to 1:12 is maintained, with the outlet cross sectional areas being derived from the sum of the individual cross sectional areas of the openings (17, 17a, 17b, 17c) of the flow restrictor (16).
8. Method according to one of the claims 1 to 7, characterized in that the flow rate of the molten metal is selectively influenced by flow paths of different lengths within the flow restrictors (16, 21).
9. Method according to one of the claims 1 to 8, characterized in that the flow rate of the molten metal after discharging from the pour nozzle (14) is reduced to a value that corresponds approximately to the discharge speed of the mold (1) or is close to it.
10. Device for carrying out the Method according to at least one of the previous claims, consisting of a distribution container (9) filled with a liquid molten metal and a pour nozzle (14), which form a pouring unit (8), and a revolving wide strip mold (1), with the pour nozzle (14) running diagonally downwards at a defined angle of inclination in which the pouring unit (8) is arranged in such a manner that there can be a difference in level of 70 to 95 mm between the bath surface (7) of the mold (1) and the filling height (H), an ascending outlet channel (11) is arranged in the distribution container (9) and the pour nozzle (14) has a distribution section (15) and a discharge section (18), with the distribution section (15) increasing in width up to the width of the strip to be poured, a first flow restrictor (16) extending over the entire cross sectional area with through-flowable openings (17, 17a, 17b, 17c) arranged between the distribution section (15) and the discharge section (18), the discharge section (18) having a spout (19) tapering in the direction of the mold (1), and the lower limit of said spout running diagonally upwards at a defined angle and fitted as a discharge strip (21) with openings (22, 22d, 22e) pointing in the direction of the bath surface (7).
11. Device in accordance with claim 10, characterized in that the discharge strip (21) is arranged at an opening angle (α) of 15 to 30° to the bath surface (7) of the mold (1).
12. Device in accordance with one of the claims 10 or 11, characterized in that the lowest point of the discharge strip (21) is above the bath surface (7), at a distance from the bath surface corresponding to 0.9 to 0.5 times the thickness of the strip to be poured.
13. Device in accordance with one of the claims 10 or 11, characterized in that the lowest part of the discharge strip (21) is in contact with the bath surface (7).
14. Device in accordance with one of the claims 10 or 11, characterized in that the discharge strip (21) is partly immersed in the bath surface (7).
15. Device in accordance with one of the claims 10 to 14, characterized in that the openings (22, 22d, 22e) of the discharge strip (21) are arranged in a row, with the openings within a row (22a, 22b, 22c) being of identical design.
16. Device in accordance with one of the claims 10 to 15, characterized in that the openings (22, 22d, 22e) have different cross sectional areas.
17. Device in accordance with one of the claims 10 to 16, characterized in that the openings (17, 17a, 17c) of the first flow restrictor (16) are arranged in a row and in the immediate vicinity of the base section (20) of the pour nozzle (14).
18. Device in accordance with one of the claims 10 to 16, characterized in that the openings (17b) of the first flow restrictor (16) are arranged in a row and limited by the base section (20) of the pour nozzle (14).
19. Device in accordance with one of the claims 10 to 18, characterized in that a connecting piece (12) with pouring channel (13) is arranged between the distribution container (9) and pour nozzle (14).
20. Device in accordance with one of the claims 10 to 19, characterized in that the pouring channel (13) arranged in the connecting piece (12) runs parallel to the horizontal and continues to increase in width in the direction of flow.

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