EP1137501B1 - Pig casting machine - Google Patents

Abstract

The invention relates to a pig casting machine comprising at least one endless conveyor belt (2), on which pig casting molds (3) are fixed, for conveying pig casting molds from a casting station (4) to a pig removal station and vice versa, wherein each pig casting mold is filled with molten metal as it passes through the casting station with the mold cavity facing upwards, in addition to a device for cooling the pig casting molds before, during and/or after casting, wherein the pig casting molds are embodied having a thin wall. According to the invention, in order to increase output and to be able to cast heavy metals in such a pig casting machine, the pig casting molds (3, 112, 207) are designed to receive molten metal at a melting temperature above 1,000° C.

Description

The invention relates to a pig casting machine according to the characteristics of the Preamble of Claim 1.

In addition, the invention relates to the use of a such a casting machine.

Liquid pig iron is known to be either after tapping in the Blast furnace fed to the steelworks by means of pans or, if not immediately can be further processed in the form of ingots, so-called ingots Shed storage or for further transport. Have pig iron pigs different weights, usually depending on the intended use a pig weighs about 6 kilograms.

Pig casting machines are used to produce pig iron. These traditionally consist of a casting station, at least an endless conveyor belt and an emptying station at the first Deflection point of the endless belt. On this endless conveyor belt are mostly a variety of thick-walled molds arranged. The respective mold is filled with molten pig iron at the casting station. The conveyor line of the ingot casting machine must then extend so far that the liquid Iron in the respective ingot mold before reaching the first deflection point of the endless conveyor belt is solidified and the shrinkage is loosening from the Mold favored. As they pass through the deflection point, they empty Casting molds automatically, or the pigs are made using an appropriate Device released from the molds. The ingot molds or molds are more well known Pig casting machines are made of cast iron. About the process of solidification To accelerate the liquid iron, the molds become sideways and additionally cooled with splash water from above.

FR-A-1 053 147 describes a ingot casting machine for casting Light metals or their alloys, especially aluminum. The single ones Pig casting molds are formed from sheets or plates of rolled steel, two sheets forming the long sides of the mold and another sheet forms the bottom of the mold, which can also be wavy can. No baskets are disclosed.

DE 114 428 C discloses a casting plant with an endless mold chain, which is used for the production of pig iron. The ingot forms exist completely Made of fireproof material, a metal for attachment to the link chain Have coat. It is therefore the combination of pig iron as something to be cast Metal and refractory (ceramic) ingot molds disclosed. The Mess form is completely absorbed by the coat in close contact.

From the German patent DE 809 948 is a pig casting machine for Casting light metals and their alloys with correspondingly low Melting points known, the ingot casting molds as an endless belt are arranged. It is suggested to use the ingot shapes instead of cast iron form from a forged metallic material, for example made of copper or aluminum or steel. It is described that it is based on this Is possible to get by with relatively thin-walled pig shapes, as they are directly cooled with water before, during and after watering can be, for example, by spraying from below.

Starting from this prior art, the invention is based on the object to provide a pig casting machine with thin-walled Ingot casting molds, which are excellent with good shape stability have cooling effect.

These objects are achieved by means of the features of claim 1. Further advantageous features are disclosed in the subclaims. One use the ingot casting machine is specified with claim 13.

The invention is based on the knowledge confirmed by tests that it The cooling of the ingot molds makes it possible, completely different from the decades retained casting of only light metals with a low melting point for casting heavy metals with Melting points above 1,000 ° C to use such casting molds, which are made of a heat-resistant material whose melting point even lower or not significantly higher than the respective melting point of the metal to be shed.

Due to the small wall thickness, the thermal conductivity of the ingot mold comes namely anyway no longer as special as this

 the known capacitive cooling is the case; rather prevents areal Cooling their melting. For the metal melts to be cast it is particularly heavy metals, such as pig iron, the is usually cast at temperatures between 1450 and 1520 ° C. The ingot molds are preferably made of copper, whose melting point is at 1083 ° C. But they are also materials with significantly lower thermal conductivity conceivable, for example heat-resistant steel, whose melting point - depending on its carbon content - around 1520 ° C lies.

Thus the criteria for the material of the ingot shape can be based on other essentials Properties are placed, in particular on the cold or Hot formability properties that determine the suitability for Rolling and preferred subsequent deep drawing, which is an inexpensive Manufacturing allowed, as well as the mechanical properties at elevated temperature, those for the shape stability of the casting mold in use and its insensitivity against cracks. A preferred proposal of the invention therefore provides that the thin-walled primary material for the ingot casting molds manufactured by rolling and then, for example, deep-drawn or is formed by die pressing.

According to the invention is improved Cooling situation suggested that baskets on the respective endless conveyor belt are attached to accommodate the individual ingot molds, the Support baskets are designed so that they are only partially in support contact with the casting molds are. On the one hand, the inner contour of the support baskets is approximately adapted to the outer contour of the ingot casting molds, and also the inner surface the support baskets with support pins for selective support of the thin-walled casting molds, preferably the diameter of the support pins on Carrier basket should not be larger than the wall thickness of the ingot shape. It will thus both the requirements in ensuring adequate Dimensional stability of the thin-walled pig shape as well as due to the only selective support of the still unimpeded cooling is sufficient done.

The carrier basket can also be designed as a lattice basket, which is the respective ingot mold supports like a net. The execution and the material for the support means are chosen so that they have a low elastic deformation do not counteract the shape of the pig because of the weight of the pig. Due to this elastic deformation and thus little expansion the form supports the removal of the ingot at the emptying station.

The carrier basket itself can have rollers that run along guide rails to run. According to another embodiment, the basket is over corresponding Holding means suspended in two parallel chains.

With the support basket it is possible to cover the wall of the respective casting mold train very thin. Have molds with thin walls the advantage that the risk of cracking due to thermal stress is minimized. With decreasing wall thickness, the form stability decreases, whereby this disadvantage is compensated for by the supporting effect of the carrier basket. Due to the partial support by means of the support pins or the grid is a cooling of the ingot molds and thus the casting Spraying or immersing in a bath is not significantly hindered. at Carrying basket with support pins should be the diameter of the Support pins on the carrier basket correspond at most to the wall thickness of the ingot shape, so that the cooling at the points of application of the support pins is not impaired becomes. Overall, a stable ingot mold with cheap Cooling properties provided. The melt solidifies faster, the circulating speed of the endless belt can be increased and thus the amount of melt spilled per time interval.

Alternatively, the belt can be shorter and at an unchanged rotational speed then run cheaper.

As an embodiment, the overlap area of the To provide the edges of adjacent casting molds with refractory material, preferably the hot-mold edge area in the overlap area is molded in such a way that a recess for receiving the refractory material arises. Starting from this recess are anchoring means intended for the refractory material.

Because in the area of the overlap of two adjacent casting molds for the upper one does not have sufficient heat dissipation by injection with water from below is possible in this way a heat protection hot-sided edge surface created. This solution has the advantage that due to of the refractory material the use of cooling water spray in the overlap area can be reduced and thus the risk of splashing through in Water entering the mess form is reduced.

In a preferred embodiment, the ingot molds are made of one Composite layer material made, with a material for the hot-side layer is chosen whose melting point is higher than that of copper, in particular a heat-resistant steel, and for the cooling-side layer the highly conductive and crack-resistant copper is chosen. The composite material is preferred produced by roll or explosive plating with subsequent forming, for example, by deep drawing, die pressing or the like.

Overall, the wall thicknesses of the ingot casting molds should range between 3 to 20 mm and the ratio of the weight of the pig shape to the weight of the pig are in the range between 0.5 and 2. Conventional cast iron pots where only the heat dissipation through the metal wall (so-called capacitive Cooling) is used, in contrast, have a weight ratio Cheating form / cheating from much larger than 1 to typically 6.

As a further preferred embodiment it is proposed that a pig casting mold comprises a plurality of individual tundishes or mold troughs. The ingot casting molds can also have a cuboid floor surface or cuboidal tundishes, which is a great advantage in production which means molds.

According to a preferred embodiment, the ingot molds are short before, during and after the casting process until the solidified pig is ejected cooled from below, preferably by spraying cooling water on the surface or a water-air mixture. The spray nozzles can vary depending on the location required cooling capacity must be arranged densely or less densely. In the Spray cooling evaporates most of the sprayed water on the underside the slang forms. Unevaporated dripping water is in a gutter captured and reused. The gutter also forms part of one Enclosure for suction and, if necessary, condensation of the resulting water vapor. An additional cooling device between the emptying station and the casting station is possible, but because of the low storage heat Thin-walled pig shapes are not absolutely necessary. Furthermore can cleaning devices and / or devices for application of mold sizing for the empty ingot casting molds.

According to the features of claims 11 and 12, the endless belt should not be like known in conventional designs, with an upper and lower run, but be arranged horizontally in the manner of a carousel. The molds for this purpose along the carousel arrangement by a circle of less moved as 360 ° by filling them with melt at the casting station, go through the arc and at the emptying station just before the pouring station is arranged to be emptied. For this, the molds rotated or tilted by 180 °. A cooling device in the form of spray nozzles and / or a cooling water sump are arranged so that they are just before start the pouring station and extend to the emptying station. As The diving tank may also come with the water collecting tank for the dripping water or the condensed water in question. Overall, when using this Design reduced the number of ingot casting molds used, and the Optimized time utilization.

The ingot molds are proposed as a preferred embodiment to be double-walled and to be cooled by means of continuous water cooling. For this purpose, a ring distribution line is proposed in the carousel arrangement, according to the ingot molds in a horizontal carousel arrangement rotates and from a rotating pipe in the center of the Carousels is fed, the ring manifold having hoses that in turn feed cooling sections that are in the spaces of the double wall trained ingot molds.

Figur 1

eine Seitenansicht einer Masselgießmaschine;

Figur 2

eine Draufsicht der Masselgießmaschine nach Figur 2;

Figur 3

eine schematische Darstellung von hintereinander angeordneten Masselgießformen als Draufsicht;

Figur 4

die schematische Darstellung des Querschnitts A-A der Figur 1;

Figur 5

die schematische vergrößerte Darstellung des Querschnitts längs der Breitseite einer Masselgießform mit Tragkorb;

Figur 6

die schematische Draufsicht einer Masselgießform mit Tragkorb;

Figur 7

die schematische Darstellung des Querschnitts entlang der Längsachse der Masselgießform der Figur 6;

Figur 8

die schematische vergrößerte Darstellung des Querschnitts des Überlappungsbereichs zweier benachbarter Masselgießformen mit Feuerfestschicht.

Figur 9

die schematische Darstellung des Querschnitts längs der Breitseite einer Masselgießform aus Verbundschichtmaterial;

Figur 10

eine Draufsicht auf eine Masselgießform mit mehreren Formmulden;

Figur 11

die Schnittansicht A-B der Masselgießform nach Figur 10;

Figur 12

eine Draufsicht auf eine Masselgießmaschine in Karussellanordnung mit den einzelnen Stationen;

Figur 13

eine seitliche Schnittansicht der Karussellanordnung mit einer Kühlvorrichtung als Ringverteilerleitung.

Further details, features and advantages of the invention result from the claims and the following description. Show it:

Figure 1

a side view of a pig casting machine;

Figure 2

a plan view of the ingot casting machine according to Figure 2;

Figure 3

a schematic representation of consecutively arranged casting molds as a top view;

Figure 4

the schematic representation of the cross section AA of Figure 1;

Figure 5

the schematic enlarged representation of the cross section along the broad side of a pig casting mold with support basket;

Figure 6

the schematic plan view of a pig casting mold with a basket;

Figure 7

the schematic representation of the cross section along the longitudinal axis of the ingot casting mold of Figure 6;

Figure 8

the schematic enlarged representation of the cross section of the overlap area of two adjacent ingot casting molds with refractory layer.

Figure 9

the schematic representation of the cross section along the broad side of a pig casting mold made of composite layer material;

Figure 10

a plan view of a pig casting mold with several mold cavities;

Figure 11

the sectional view AB of the ingot casting mold according to Figure 10;

Figure 12

a plan view of a pig casting machine in a carousel arrangement with the individual stations;

Figure 13

a sectional side view of the carousel arrangement with a cooling device as a ring manifold.

The pig casting machine according to Figure 1 or 2 is made up of the essentials Elements casting station 1, two parallel endless conveyor belts 2a, b with one A large number of ingot molds 3 arranged thereon (shown by way of example) and an emptying or collecting station 4 together. The endless belts are used to transport ingot molds from the casting station to the emptying station and vice versa, each ingot mold in the casting station is filled with molten metal with the mold cavity pointing upwards. For this liquid pig iron is delivered with torpedo pans 5 (see FIG. 2) and into the individual ingot molds by means of a suitable casting device 6 poured continuously.

In the embodiment shown, an endless belt 2 consists of a trough chain and becomes two by forming an upper and a lower run Rollers 7a, 7b, which are at the casting station 1 and emptying station 4th located and operated by means of a sprocket drive station. In the The embodiment according to FIG. 1 transports the respective endless belt 2 with their molds upward-pointing molds 3 upwards. When reached the emptying station 4, the pig iron masses have solidified to the extent that they automatically along the deflection point of the belt around the roller 7b fall out of the molds. The pigs fall on a pond slide 8, which is divided into two sliding elements, and are divided into one Wagon or container (not shown) collected. Especially just before Pouring station, in the pouring station and between this and the emptying station cooling devices (not shown) are provided in the form of injection nozzles, so that the ingot molds are spattered from below. The stations 1 and 4 are each enclosed in a vapor-proof manner by means of suitable housings 9 and 10. The endless conveyor belts 2 are partially protected by a housing 11.

Figures 3 and 4 show schematically the top and sectional view A-A Detail of such an endless belt 2 with several arranged adjacent thin-walled ingot casting molds, whereby only one casting mold follows is described as an example. The mold 12 is with a corresponding Mold trough 13 provided for receiving the melt. The two border areas 14, 15 of a casting mold overlap each other along their longitudinal axis with the edge areas of the neighboring molds. The overlap areas are marked here with 16 and 17. Because of the overlapping Casting is a continuous casting process with a continuous process moving endless belt possible. Here, an edge region forms a casting mold in each case the cooling-side edge region 14 and on the other side the hot side edge area 15, which overlaps the other and thus with the hot melt comes into direct contact. Such a molded mold tape is from below with cooling water from nozzles, here example nozzle 16, splashing.

In Figure 5 is a sectional view of the inclusion of such a thin-walled Pig casting mold 12 shown in a carrier basket 17. The carrier basket consists of a support structure 18, which is provided with support pins 19 which the ingot mold Support 12 selectively. Figure 6 shows in plan view that the support structure 18 is provided with two idler rollers 23a, 23b, which on one Longitudinal bolts 20 are mounted. The rollers run on corresponding guide rails 21a, 21b (see FIG. 7). To ensure that the endless belt runs straight are the rollers 23a, 23b with outside flanges 22a, 22b Mistake. Figure 7 makes it clear that the baskets 12 from below with cooling water be splashed.

In addition to stabilizing the shape of the thin-walled casting molds Carrying baskets are proposed, the overlapping edge regions adjacent Protect ingot casting molds with a layer of refractory material, cf. Figure 8, which is a detailed view of Figure 4. This is the hot side edge 150 shaped so that a recess 151 is formed, which is the refractory material 152 records. Anchoring means 153 are provided along the recess 151 hold the refractory material. In comparison with Figure 4 it is clear that the Areas that are less easily reached by spray cooling through the fireproof material to be protected. The arrangement of the refractory material is also clear in the embodiment according to FIG. 9, here the ingot mold is made of a composite layer material. On the hot side the casting mold from a layer of 154 heat-resistant steel, on the cooling side a copper layer 155.

Figure 10 illustrates an embodiment of the plated mold 112 with four Casting troughs 156a to 156d. Such plated molds can be made with appropriate Holding elements 157a, b connected to a drive chain (not shown) become. Figure 11 shows the sectional drawing A-B of Figure 10, here the wall area due to the cooling hose of the Cooling system in Figure 13 is drawn relatively thick.

FIG. 12 provides a top view of an overview of a pig casting machine 200 in the embodiment of a horizontal carousel arrangement, with the Arrow the direction of rotation of the endless belt 203 is indicated. The single ones Stations of the ingot casting machine 200 are shown schematically. At 201 is the casting station and therefore the point of application for the pig iron in the casting molds designated. A cooling device is in front of the casting station 201 Arranged by nozzles or sumps with cooling water that are up short extends in front of the drop station 202. The beginning and end of the cooling device are shown schematically with dash-dotted lines. The drop station 202 can are shortly before the casting station 201, since the ingot molds after the Empty only need to be cooled to a small extent. at Passing through the collecting troughs, the area is cooled by the Immerse the bottom of the ingot molds in the cooling water.

As an alternative to cooling using spray nozzles or a collecting trough, preference is given to a water flow cooling with a ring distributor line proposed, as shown in Figure 13. For this is in the center of the endless belt carousel 203 a rotating union 204 is provided with a cooling water inlet 205. The rotary drives for the cooling device and the endless belt for the Casting molds are not shown. By means of this rotating feed 204 becomes a ring distributor line 205 which also rotates with the endless belt fed via radially extending feed lines 206 a, b, each with a pig casting mold 207 a, b etc. a supply line 206a, b etc. is assigned. For connection the feed lines 206a, b etc. to the ingot casting molds are hoses 208a, 208b provided. These hoses 208a, b enable tilting and Rotating the individual ingot molds 207a, b when they are emptied. This Hoses 208a, b in turn feed cooling tubes 209 a, b, which in the double-walled trained casting molds are arranged (see also figure 11). These cooling hoses 209a, b are each with hose connections 210 and processes 211 provided. In the embodiment shown, this is Cooling water after passing through the respective casting mold in a collecting trough 212a, 212b, the bottom of the collecting trough 212a, 212b is inclined towards the end. It is also a link to one under Coolant circuit under pressure is conceivable. Overall, the Guides for the endless belt 203 on a corresponding support structure 213th

A pig casting machine with the proposed molds can be due the higher performance not only in iron foundries, but also in integrated iron and steel works as an alternative for ladle transport or for a Pouring the pig iron in pits, which is polluting due to the emissions is used. Likewise, the use of such casting machines in electrical steelworks with a direct blast furnace conceivable. It is therefore possible due to different production cycles and availabilities of excess pig iron available to pigs to be shed, which can then be added later in the Electric furnace can be melted down.

Claims (13)

1. Pig casting machine comprising at least one endless transport belt, on which pig casting moulds are fastened, for the transport of pig casting moulds from a casting station to a pig emptying station and vice versa, wherein each pig casting mould is filled with metal melt during transit, with the mould trough facing upwardly, through the casting station, as well as a device for cooling the pig casting moulds before, during and/or after the casting, wherein the pig casting moulds are constructed to be thin-walled and consist of a material having a melting temperature lower than the melting temperature of the metal to be cast, which lies above 1000° C, or consists of a heat-resistant steel, characterised in that carrier baskets (17) are fastened to the respective endless transport belt for reception of the individual pig casting moulds (12), wherein the carrier baskets are so formed that they come only partly into supporting contact with the pig casting moulds, wherein the inner contour of the carrier baskets is approximately matched to the outer contour of the pig casting moulds and is provided with support pins (19) for punctiform support of the thin-walled pig casting moulds.
2. Pig casting machine according to claim 1, characterised in that the pig casting moulds consist of rolled start material.
3. Pig casting machine according to claim 1, characterised in that the diameter of the carrier pins at the carrier basket is not greater than the wall thickness of the pig mould.
4. Pig casting machine according to claim 1, characterised in that the support baskets are constructed as a grating basket which supports the respective pig casting mould in reticular manner.
5. Pig casting machine according to claim 1, characterised in that the edge regions of adjacent pig casting moulds overlap and the regions (150) of overlapping are provided with refractory material (152).
6. Pig casting machine according to claim 5, characterised in that the respective casting mould edge region (150) at the hot side in the region of overlapping is so shaped that a depression (151) for reception of the refractory material (152) arises and that anchoring means (153) for the refractory material are provided to extend out from this depression.
7. Pig casting machine according to claim 5 or 6, characterised in that the pig casting moulds consist of a composite laminated material, wherein a material having a melting point higher than that of copper is selected for the layer (154) at the hot side, particularly a heat-resistant steel, and copper is selected for the layer (155) at the cooling side.
8. Pig casting machine according to claim 1, characterised in that the wall thickness of the respective pig casting mould lies in the region between 3 and 20 mm and the ratio of the weight of the pig mould to the weight of the pig lies in the region of 0.5 to 2.
9. Pig casting machine according to claim 1, characterised in that a pig casting mould comprises a plurality of individual casting troughs (156a to 156d).
10. Pig casting machine according to claim 1, characterised in that the cooling device comprises nozzles (16) for targeted spraying of a coolant onto the casting moulds, in particular for targeted spraying from below, or is constructed as a through trough which is filled with the coolant and in which the undersides of the casting moulds are partly immersed during transport.
11. Pig casting machine according to claim 1, characterised in that the endless belt (203) extends horizontally in correspondence with a carrousel arrangement and devices for separating the pig casting moulds from one another as well as for emptying by a rotary or tipping movement are provided at the emptying station (202).
12. Pig casting machine according to claim 11, characterised in that the cooling device comprises an annular distributor duct (205) which co-rotates in correspondence with the pig casting moulds in horizontal carrousel arrangement and is supplied by a rotating feed duct (204) in the centre of the carrousel, wherein the annular distributor duct (205) comprises hoses (208a, b) which in turn supply cooling cross-sections (209a, b) which are formed into intermediate spaces by pig casting moulds (207a, b) constructed to be double-walled.
13. Use of a pig casting machine comprising at least one endless transport belt, on which pig casting moulds are fastened, for the transport of the pig casting moulds from a casting station to a pig emptying station and vice versa, wherein each pig casting mould is filled with metal melt during transit, with the mould trough facing upwards, through the casting station, as well as a device for cooling the pig casting moulds before, during and/or after the casting, wherein the pig casting moulds are constructed to be thin-walled, characterised in that heavy metal melts are cast in the pig casting moulds which consist of a material having a melting point lower than the respective melting point of the heavy metal to be cast.

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