EP2752260B1 - Refractory ceramic floor - Google Patents

Description

The invention relates to a refractory ceramic floor in the connection region to at least one wall of a vessel for the treatment of a high-temperature melt,

The vessel may be, for example, a metallurgical ladle. The state of the art and the invention are described in more detail below with reference to this use.

Such a pan is for example in the US 5,879,616 A or in "Revue de Metallurgie, Vol. 88, No. 718, 1.7.91, S-781-788". To simplify matters, it consists of a floor and a wall extending from the floor upwards, with a mostly round inner cross-section, so that overall a kind of pot shape results. At least one hole (spout area) is arranged in the floor.

A treated in the pan molten metal passes through the spout (tapping) in a downstream system, such as a tundish. For controlling / controlling the amount of molten metal, for example, a stopper closure (English: stopper) or a slide valve (English: sliding plate valve), also called control organs.

If slag gets into the tundish, the quality of the steel and the durability of the tundish are reduced. An attempt is therefore made to close the pouring spout immediately as soon as slag has reached the spout area. The pan is then dumped with the remaining amount of melt and slag. Thereby

There are significant losses of material and high costs for reprocessing.

Since the slag is lighter than the molten metal (molten steel), the slag floats predominantly on the metal bath. It has therefore sloped the surface of the pan floor designed to transport as much liquid metal through the spout, which is located at the lowest point of the soil before the slag flows through it.

This requires a correspondingly complicated shape of the soil. The refractory lining of the soil is complex and expensive. The floor according to "Revue de Metallurgie" has these disadvantages, because the cuboid stones can not be set accurately on the curved surface of the permanent food.

The invention has for its object to provide a construction in which as much melt can be removed in good quality from a melting vessel.

• Prinzipiell ist es vorteilhaft, wenn die Schmelze entlang einer Schrägfläche zum Ausguss transportiert wird. Deshalb soll der erfindungsgemäße Boden mindestens abschnittweise gegenüber der Horizontalen geneigt sein. Die Schrägfläche soll insbesondere zum Ausgussbereich hin abfallen.

In order to achieve this object, the invention provides the following measures:

• In principle, it is advantageous if the melt is transported along an inclined surface to the spout. Therefore, the floor according to the invention should be inclined at least in sections relative to the horizontal. The inclined surface should fall off in particular towards the spout area.

In order to reproducible conditions belm pouring the shape of the soil over which the melt flows, should always be the same. This means that the shape of the soil, and in particular the surface of the soil, even after repair or replacement of the spent refractory material is as unchanged as possible (in the field of technical tolerances).

A newly manufactured monolithic wear lining, as it is in the US 5,879,616 is described, inevitably has a different geometry after a repair.

The invention goes the way according to "Revue de Metallurgie": The soil is formed from a refractory permanent lining on which a wear lining is arranged, but in a different design.

The permanent lining, or more precisely: the surface of the permanent lining, specifies the desired geometry for the wear lining. The permanent feed accordingly has at least one inclined surface and a three-dimensional shape and at least one step.

The permanent food must not be renewed for a long time, because it is not subject to wear. Only the wear lining located on the permanent lining is consumed and must be repaired or renewed from time to time.

If the wear lining is laid on the permanent lining in the form of refractory bricks, it follows immediately that the upper side of the wear lining has the same or essentially the same shape (geometry) as the upper part of the permanent lining. This is especially true when the stones of the wear lining are mainly identical and are mainly laid in the same direction.

This also applies if individual stones, stone areas or the entire wear lining are repaired or renewed, because the permanent lining dabel remains untouched and continues to define the desired surface geometry.

The above features apply within the scope of the technical conditions. An (inclined) floor on a refractory ceramic material can never be exactly planar (planar inclined) in the mathematical / physical sense and it inevitably result in a ladle with a round inner cross section transitions from the stones to the wall or between stones and spout, which in one separate work step must be completed. For this purpose, further notes are given below. However, these are only remedial measures, since the largest part of the wear layer can be built up from standard shaped bricks.

In its most general embodiment, the invention relates to a refractory ceramic floor in the connection region to at least one wall of a vessel for the treatment of a high-temperature melt, with the features of the main entitlement.

Information such as "top, bottom" etc. always refer to the normal operating position of the vessel.

The term "solid brick" covers all types of classic refractory ceramic bricks, regardless of their geometry or composition. Solid bricks are in particular compact refractory bricks in the form of a cuboid, a column or a three-dimensional polygon with a largely homogeneous internal structure. The open and / or closed porosity should be as low as possible, for example <20% by volume, better <15% by volume, <10% by volume or <5% by volume.

In particular, those stones are excluded which have a passage opening or individual larger cavities and / or stones for special metallurgical applications such as gas purging bricks and other functional components.

However, a nozzle or a gas purging plug can be installed as a discrete, independent component in both the permanent and the wear chuck. "Discrete independent component" refers to a use regardless of the wear lining.

According to the invention as far as possible at least 60M .-% of the wear lining consist of such solid bricks. The value may also be> 65M .-%,> 70M .-%,> 75M .-%, <80M .-%,> 85M .-%,> 90M .-%,> 93M .-% or> 95M% , The percentage of solid bricks depends on the shape, dimensions and size of each pan. It should be as high as possible in order to best reproduce the surface structure of the permanent feed.

The remainder may for example be formed of a refractory mass, which is used in the transition region between adjacent stones, between stones and wall or other components / internals, in the spout area, etc., to fill gussets. For this purpose, further information will be given below.

In one embodiment, the permanent feed consists of at least one monolithic refractory mass. The entire permanent feed can be produced in-situ or at any location, even outside the plant in which the melting pot is used. It is advantageous to carry out the permanent feed as prefabricated component. The prefabricated component may be one or more parts (for example 2 to 10 parts) and consist for example of segments which complement each other to form a complete permanent feed. The permanent lining of the soil is then installed in the pan and then laid the wear lining on the permanent feed.

The three-dimensional shape of the permanent lining is important because it dictates what the surface texture of the wear lining is. The surface structure of the wear lining is important because this surface has contact with the melt and to be able to derive as much melt in good quality through the spout.

• Einen Aufbau zur Ausbildung eines Prailbereichs (einer Prollplatte, englisch: impact pad) für die Schmelze
• Eine Stufe zum Abfließen der Schmelze
• Eine Vertiefung zum Einbau eines Gasspülsteins (englisch: gas purging plug), eines Lochsteins (englisch: well block) oder dergleichen,
• Eine wannenartige Vertiefung
• Eine nach oben weisende Wand zur Ausbildung eines Damms (englisch: weir)

The permanent feed may additionally have various structures or installations, for example:

• A structure for the formation of a Prailbereichs (a Prollplatte, English: impact pad) for the melt
• A stage to drain the melt
• A recess for installing a gas purging plug (English: gas purging plug), a block (English: well block) or the like,
• A trough-like depression
• An upward wall for the formation of a dam (English: weir)

The wear lining takes over these forms directly, as explained above.

The surface of the permanent lining and thus the corresponding surface of the wear lining can be fully or partially inclined. The maximum slope is usually 45 ° to the horizontal, with upper possible limits at 30 °, 25 °, 20 °, 15 ° or 10 ° and possible lower limits at 1.5 °, 2 °, 3 °, 4 °, 5 ° or 8 °.

According to one embodiment, the surface of the permanent lining, which is adjacent to the wear lining, is inclined at least in sections relative to the horizontal by 2 ° to 25 °. Sections near the spout opening (tapping) may have a greater incline than sections in the wall region of the metallurgical vessel.

• mindestens 75% der Vollziegel des Verschleißfutters sind einlagig verlegt. Eine höhere Übereinstimmung wird erreicht, wenn der Wert >80%, >85%, >90% oder sogar >95% beträgt.
• mindestens 60%, besser mindestens 65%, 70%, 75% oder 80% der Vollziegel des Verschleißfutters sind baugleich. Die Parallelität zwischen den Oberflächen des Dauerfutters und des Verschleißfutters wird optimiert, wenn mehr als 85%, beispielsweise >90% oder >95% der Steine (englisch: bricks) des Verschleißfutters baugleich sind.
• Die Steine des Verschleißfutters werden überwiegend (>80%, >85%,>90%, >95%) in gleicher Orientierung oder in einem einheitlichen Muster (english "pattern"), beispielsweise "Fischgrätmuster" verlegt

The surface shape of the wear lining corresponds all the more to the surface shape of the permanent lining, if the following parameters are considered at least individually, better in combination:

• At least 75% of the solid bricks of the wear lining are laid in one layer. A higher match is achieved if the value is>80%,>85%,> 90% or even> 95%.
• at least 60%, better at least 65%, 70%, 75% or 80% of the bricks of the wear lining are identical. The parallelism between the surfaces of the permanent lining and the wear lining becomes optimized if more than 85%, for example> 90% or> 95% of the bricks of the wear lining are identical.
• The stones of the wear lining are mainly laid (>80%,>85%,>90%,> 95%) in the same orientation or in a uniform pattern (English "pattern"), for example "herringbone pattern"

The invention makes it possible to use the solid bricks of the wear lining at least partially as prefabricated segments of a plurality of solid bricks. This can simplify repair work.

As stated, the geometry of the stones is not critical. But it is particularly easy to produce floors whose wear lining consists of at least 70M .-% or at least 75M .-% of solid bricks, which have a triangular, rectangular or polygonal profile in a plan view.

According to another variant consists of at least 80M .-% bricks from solid bricks, which have their greatest longitudinal extent in the vertical direction.

In principle, the bricks of the wear layer can be made of any refractory material, for example of at least one material of the following group: magnesia (MgO), alumina (Al ₂ O 3), magnesia-carbon (MgO-C), doloma (MgO-CaO). Magnesia chromite (MgO-Cr ₂ O ₃ ), TiO ₂ .

• zwischen den Vollziegeln,
• zwischen den Vollziegeln und dem Dauerfutter,
• zwischen den Vollziegeln und einem separaten Bauteil im Boden

In the pan with a round inner cross-section and cuboidal stones for the Dauer-. Or wear lining inevitably arise gusset between the floor and wall. For example, analogous gussets can arise

• between the solid bricks,
• between the solid bricks and the permanent feed,
• between the solid bricks and a separate component in the ground

These gussets can be filled with a refractory ceramic mass. The application can be done manually or automatically, for example by pounding, spraying, pouring or grouting.

To avoid joints between adjacent solid bricks (bricks) of the wear lining, a variant of the invention provides the following: solid tiles, which lie on a surface of the permanent lining, which is inclined relative to the horizontal by at least 1.5 °, are arranged, for example staggered, such shown in the figure description (if no flat edition is possible).

• für das Verschleißfutter können beliebige feuerfeste Sorten verwendet werden
• für ein monolithisches Dauerfutter sind Massen sinnvoll die eine gute Festigkeit und Hydratationsbeständigkeit aufweisen, beispielsweise Alumina-Massen
• die Montagezeit des Bodens ist kurz, weil das Dauerfutter, das nicht erneuert wird, bereits die Form der Oberfläche des fertigen Bodens definiert
• die Montage des Dauerfutters als Fertigbauteil optimiert die Montage der gesamten Bodenzustellung
• Fehler bei der Montage sind weitgehend ausgeschlossen, da das Dauerfutter unverändert bleibt
• Die Verlegung der Steine der Verschleißschicht ist einfach, Fehler bei der Auswahl der Formate oder Positionierung der Steine werden minimiert
• Es lassen sich auch komplexe Bodenformen herstellen
• Einbauten und Aufbauten können einfach integriert werden
• Das Dauerfutter ist nicht in Kontakt mit der Schmelze; dadurch wird seine Gebrauchsdauer (englisch: service time) zusätzlich erhöht, auch wenn minderwertigere feuerfeste Materialien verwendet werden. Das Profil des Dauerfutters bleibt dauerhaft erhalten.
• Während des Abstichs muss das Gefäß nur wenig gekippt werden
• Der Verbrauch an Feuerfestmaterial wird reduziert.

The invention offers the following advantages over the prior art:

• Any number of refractory grades can be used for the wear lining
• For a monolithic permanent food masses are useful which have good strength and hydration resistance, for example, alumina masses
• The installation time of the soil is short, because the permanent food, which is not renewed, already defines the shape of the surface of the finished soil
• the assembly of the permanent feed as prefabricated component optimizes the assembly of the entire floor feed
• Mistakes during assembly are largely excluded because the permanent food remains unchanged
• The laying of the stones of the wearing course is simple, mistakes in the choice of the formats or positioning of the stones are minimized
• It can also produce complex soil forms
• Built-in components and superstructures can be easily integrated
• The permanent feed is not in contact with the melt; This additionally increases its service life, even if inferior refractory materials are used. The profile of the permanent food is permanently preserved.
• During tapping, the vessel only needs to be tilted slightly
• The consumption of refractory material is reduced.

Further features of the invention will become apparent from the features of the claims and the other application documents. Here are individual Characteristics may also be used in other combinations, unless expressly excluded or technically nonsensical.

Fig. 1:

eine perspektivische Ansicht eines erfindungsgemäßen Bodens einer Stahlgieß-Pfanne in Explosionsdarstellung (Fig. 1a, b) und nach Zusammenbau (Fig. 1 c)

Fig. 2:

einen Teil-Querschnitt durch einen ersten Abschnitt des Bodens

Fig. 3:

einen Teil-Querschnitt durch einen zweiten Abschnitt des Bodens

Fig. 4:

einen Teil-Querschnitt durch einen dritten Abschnitt des Bodens

Fig. 5:

einen Teil-Querschnitt durch einen vierten Abschnitt des Bodens

Fig. 6:

einen Querschnitt durch eine Pfanne mit dem Boden analog Fig. 1

The invention will be described below with reference to various embodiments. The figures show, in a highly schematic representation, the following

Fig. 1:

a perspective view of a floor according to the invention a Stahlgieß pan in an exploded view ( Fig. 1a, b ) and after assembly ( Fig. 1 c)

Fig. 2:

a partial cross-section through a first portion of the floor

3:

a partial cross section through a second portion of the soil

4:

a partial cross-section through a third section of the soil

Fig. 5:

a partial cross-section through a fourth section of the floor

Fig. 6:

a cross section through a pan with the bottom analog Fig. 1

In the figures, identical or equivalent components are provided with the same reference numerals. The structure is described when the pan is aligned exactly vertically.

FIG. 1 shows a bottom with two layers, namely a lower layer 10 and an upper layer 20 arranged thereon. Both are approximately circular in plan view.

• etwa in der Mitte eine erste Stufe 13
• im linken oberen Drittel eine erhöhte Prallfläche 14
• alle Bereiche der Oberfläche 10o sind um ca. 3° geneigt zur Horizontalen - mit Gefälle in Richtung eines Ausgusses 30.

The lower layer 10 is designed as a permanent lining and consists of a refractory ceramic mass based on alumina. The permanent lining 10 is made entirely as a prefabricated part and has a horizontal lower surface 10u and a three-dimensionally shaped upper surface 10o. The surface 10o has the following areas:

• approximately in the middle of a first stage 13th
• in the upper left third an increased baffle 14th
• all areas of the surface 10o are inclined by about 3 ° to the horizontal - with a slope in the direction of a spout 30th

The upper layer 20, ie the wear layer, consists predominantly (to> 80M .-%) of cuboid refractory bricks 21 of the same size in a similar installation, except in the region of the spout 30th

This results in that the geometry of the underside 20u and the upper side 20o of the wear layer 20 largely follows the geometric specification of the upper side 10o of the permanent lining 10.

Differences arise at most by the fact that the stones 21 (solid brick), for example, in the area of the stage 13 (inclination: about 90 °) are slightly offset laterally, such as FIG. 2 shows. The thus formed space 23 between top 10o of the permanent lining and the bottom 20u of the stone 21.1 is filled with a refractory mass based on alumina.

This applies analogously to steps in areas with a slope of, for example, 25 ° ( FIG. 3 ) or the positioning of the solid brick 21 in successive inclined surfaces with different inclination ( Fig. 4 ).

Fig. 5 shows an embodiment in which the planar inclined surfaces of the Figures 3 . 4 replaced by a staircase-like contour, however, the total - technically speaking - a slope similar to in FIG. 3 results. In that regard, the term "inclined surface" technically also includes embodiments with corresponding, successive small steps 13 (FIG. Fig. 5 ).

As the FIGS. 1 and 6 gussets Z also exist between bricks 21 and an adjacent curved vessel wall 52 of a steel pouring ladle 50. These areas are also filled with a monolithic refractory mass.

In a floor according to the invention, only the wear lining 20 is replaced. For this purpose, the stones 21 and any other components of the wear lining 20 are degraded. The permanent feed 10 remains unchanged. The new wear layer 20 is thus built up again on the existing geometry of the permanent lining 10, so that the upper side 20o of the Verschieißfutters 20 again corresponds to the surface geometry of the Dauerfutters 10.

For a simple, quick and inexpensive repair option is given, the 3-dimensional design is automatically determined by the unchanged permanent lining 10.

Claims (13)

1. Fireproof ceramic base in the connection area to at least one wall (52) of a vessel (50) for the treatment of a high temperature melt, with the following characteristics:

   a) the base features at least two layers (10, 20), namely

   b) a lower layer made of a fireproof ceramic permanent lining (10) with at least one step (13), and

   c) an upper layer made of a fireproof ceramic wear lining (20), wherein

   d) the permanent fining (10) features a surface (10o) which is adjacent to the wear lining (20), which is sloped by at least 1 ° compared to the horizontal,

   e) this surface (10o) features a three dimensional design, and

   f) the wear lining (20) consists to at least 60M.-% of fireproof ceramic solid bricks (21),

   g) the permanent lining (10) and the wear lining (20) feature at least one inconsistency for the integration of at least one common discharge opening (30) for the high temperature melt.
2. Base according to claim 1, whose permanent lining (10) mainly consists of at least one monolithic fireproof mass.
3. Base according to claim 1, whose permanent lining (10) is a premade element which has been made out of at least one monolithic fireproof mass.
4. Base according to claim 1, wherein the surface (10o) of the permanent lining (10), which is adjacent to the wear lining (20) is, at least in segments, sloped by 2° to 25° compared to the horizontal.
5. Base according to claim 1 with at least one separate element (14, 30) which is built into the permanent lining (10) and the wear lining (20).
6. Base according to claim 1, wherein at least 75% of the solid bricks (21) of the wear lining (20) are laid in a single layer.
7. Base according to claim 1, wherein at least 60% of the solid bricks (21) of the wear lining (20) are identical.
8. Base according to claim 1, wherein the solid bricks (21) of the wear lining (20) are at least partially arranged as pre-assembled segments consisting of multiple solid bricks.
9. Base according to claim 1, whose wear lining (20) consists of at least 70M.-% solid bricks, which feature a triangular, rectangular or polygonal profile in the top view (plan view).
10. Base according to claim 1, whose wear lining (20) consists of at least 80M.-% solid bricks (21), which have their largest extension in a vertical direction.
11. Base according to claim 1, wherein the solid bricks (21) of the wear lining (20) consist of at least one material of the following group: Magnesia, Alumina, Magnesia-Carbon, Doloma, Magnesia-Chromite.
12. Base according to claim 1 or 5, wherein pendentives (23)

    - between the solid bricks (21)

    - between the solid bricks (21) and a wall (52) of the vessel (50)

    - between the solid bricks (21) and the permanent lining (10)

    - between solid bricks (21) and a separate element (14, 30) in the base are at least partially filled with a fireproof ceramic mass.
13. Base according to claim 1, wherein the solid bricks (21) are arranged offset in a step-like manner in the area of a surface (10o) of the permanent lining (10), which is sloped by at least 1.5° compared to the horizontal.

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