JP3386794B2 - Container for molten metal for metallurgy - Google Patents

Abstract

A pouring ladle (100) for molten steel has a monolithic fire-resistant lining (8) of the base which comprises a continuous gradient sloping from all directions toward and up to the outlet (25). A deflecting element (30) has a convex arched upper side (33) which extends the useful life of the lining.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for molten metal for metallurgy according to the preamble of claim 1 and a mold that can be used in the manufacture of such a container.

[0002]

2. Description of the Related Art So-called ladles, which are understood as examples of such vessels, are used for transporting molten steel or other molten metal in iron and foundry plants. The ladle is lined with a refractory material whose task is to protect the steel jacket of the ladle from the hot melt and to reduce the temperature loss of the molten metal by its insulating action. In this case, the refractory lining, which is in contact with the erosive melt having a high temperature, must not release components into the melt that would impure the melt.

In the recent past, ladle was developed,
It has become an important factor in the secondary metallurgical processing of steel. With this treatment, injecting an inert gas to generate a stirring effect in the molten metal, sending an auxiliary agent such as lime dust for desulfurization, charging a plurality of alloying elements and melting, And to improve the purity of molten steel.

When casting a ladle up to 300 tonnes, when emptying the ladle, it is better to leave as little steel as possible at the bottom of the ladle. This is because this means a loss and the hardened cast steel formation can be very disturbing when tilting the ladle for the purpose of emptying the slag.

From DE 197 38 709 A1, the bottom region of the metallurgical vessel has a surface inclined towards the outlet (gate), which remains on the bottom when emptied. It is already known to prevent this. However, with regard to this type of refractory lining of metallurgical vessels, DE 197 38
It cannot be read from the 709 A1.

At the bottom of the lining of a ladle or other metallurgical container, in the area of impact when pouring the hot melt, a plurality of recesses are retained in which the remainder of the melt which deteriorates the yield remains and which shortens the service life, Formed by erosion.

In order to prevent this, DE 34 43 281 A1
It is already known from the document that the hitting point of the cast steel is provided with a convex deflecting element in the form of a flexing surface (Buckel flaeche) which should avoid premature wear at this hitting point.

[0008]

However, in this embodiment, the refractory lining comprises a plurality of molded refractory products. These molded refractory products are usually standard sized bricks made by pressing, and customer-specific sized castings,
It is a component formed by tamping or vibration.
In some cases, the refractory mortar is applied to the contact surface between the bricks. The refractory linings of different sizes / components of steel ladles inevitably result in seams that must be filled by tamping or pouring of suitable mortar or putty. Such a combination of materials with different physical properties causes an additional load on the refractory lining in addition to the erosion itself by the melt. In addition, the molded refractory components allow for variations in the shape of the bottom only at considerable cost.

The problem of structuring the ladle so that the amount of molten metal remaining in the ladle finally decreases is the basis of the invention.

[0010]

This problem is solved by the invention according to claim 1. The present invention is realized by the cooperation of three features.

First, the known gradient is provided from all directions toward the outlet in 360 ° with respect to the vertical axis passing through the center of the outlet. This achieves that there is no depression anywhere on the top surface of the bottom where the residual amount of molten metal may remain. Move the steel away from the bottom of the ladle as much as possible during normal pouring. This not only has the advantage of not causing any problems with the steel hardening residue when subsequently tilting the ladle, but also increases the yield per ladle according to ladle size, 0,
It is also increased by 3 to 7t.

It is provided by the convex shape and prevents the formation of depressions. The thickness of the impingement area will flatten out as the number of castings (number of charges) increases, but in any case the original convex shape will significantly extend the service life of the bottom of the ladle. Can be achieved. The convex shape of the deflecting element cooperates with other shapes of the bottom of the ladle, so that the steel that strikes the deflecting element first flows off the deflecting element, depending on the bend, and then the bottom of the ladle. Enter the gradient of. Therefore, the steel does not reach the depression by flowing through the entire gradient that extends the full length of the flow to the tap.

The irregular shape of the bottom of the lining can be formed in a feasible manner by the third feature of the integral lining of the bottom. Furthermore, the monolithic lining can exhibit the great advantage of a low erosion surface as it is seamless. A plurality of refractory linings is known, for example from DE 44 03 270 C1. In the case of such a lining, a flowable casting or vibration-filling material is used in combination with a plurality of corresponding molds, the lining being of a homogeneous material, freely formed, a seam. To give moldings free of In a preferred embodiment according to claim 2, the upper surface of the deflecting element is formed as a gentle spherical bend, which may be spherical, but this does not have to be the case. Absent. When emptying the ladle, it is necessary to reduce the amount of residual molten metal remaining in the ladle, but on the other hand, it is not possible to cast some of the liquid slag from the ladle together. Must. This is because the inclusion of slag would render the casting or cast steel unusable. In this idea, the configuration according to claim 3 has an effect. This arrangement ensures that at the end of the pouring, no large-area moldings of residual steel remain on the bottom of the ladle. From this point of view, when casting using the container according to claim 1,
It is preferable to take measures based on "Refractory lining for secondary metallurgical containers" (Feuerfeste Zustellung der G
efaesse fuer die Sekundaermetallugie) Publisher Stahl Eisen publishing house, editor Haus de Tehinique (198
According to Hammerschmidt and Andrezeevsky's work (7 years), by using the container according to the invention (dadurch) it can be ensured that no slag escapes at the end of casting. At the same time, the shape according to the invention of the bottom of the lining does not leave a considerable amount of residual steel in the ladle. In some known ladles, a tap diameter of 30 to 95 mm is typical, depending on the size of the ladle. With several conventional methods, the amount of residual steel in these ladles was unavoidable between 0,3t and 7t depending on the size of the ladles. When forming the bottom according to the invention with the casting method of claim 4, these amounts of residual steel can be significantly reduced without entrainment of slag.

A mold for producing a bottom lining of a container made of a flowable refractory material can be formed according to claim 5. In this case, as in claim 6, the arched deflection element can be formed by a separate hemisphere which can be joined to the bottom of the mould. This not only facilitates the manufacture of the mold, but also allows the use of hemispheres of various curvatures if desired. As claimed in claim 7, it is possible to provide the bottom of the mold with a connection for a supply conduit of a fluid pressure medium for supporting the removal of the mold during its removal (similar method). Then known from ZA-PS 94/8240)
Is appropriate.

[0015]

Several embodiments of the invention are shown in the drawings. A ladle, generally designated 100 in FIG. 1, is a pan-shaped steel housing having a bottom 2 which is substantially horizontal in the operative position and a vertical side wall 3 which flares slightly conically upwards. It consists of 1. As shown in FIG. 1, ladle 100 has a slightly oval outline. But,
This contour may be circular, for example. On the outside of the side wall 3 made of steel plate, horizontal pins 4 on opposite sides are attached, and a suspension device 5 is engaged with these pins. The ladle 100 can be lifted by a crane by hooking it on this suspension device. In order to empty the slag after pouring the molten metal in the ladle 100, the ladle 100 can be tilted around the axis A of the pin 4.

The housing 1 of the ladle 100 has a side wall 3
It has a stacked refractory outer lining 6. The inner plate of this outer lining is provided with reference numeral 7. The bottom 2 of the housing 1 also has an outer lining 8 that is either stacked or cast. This outer lining is held firmly on the bottom 2 by a plurality of anchors 9. The purpose is to prevent the outer lining from leaving the bottom 2 when the ladle 100 is tilted.

In the ladle 100 which has been lined, an integral lining 10 is shown inside the outer lining 6 of the side wall 3 as indicated by the chain line in FIG. That is, before making the lining 10 of the side wall 3, the lining 20 of the bottom 2 is made. This is the point here. The lining 20 has an actual bottom 21 in the shape of a base plate, and a side wall 22 which integrally stands on this bottom at the edge. This side wall is ladle 100
It extends over 3 to 30% of the height of the base and forms with the bottom 21 an integral molding in the form of a pan. The base plate of the lining 20 of the bottom 2 can have a thickness of up to 80 cm in the case of several large ladles.

The upper surface 23 of the bottom portion 21 is not flat and has a predetermined undulation. This undulation has a slope in the path from any point on the upper surface 23 to the tap hole 25, and this slope is the entire course, that is, a certain volume element of the molten metal is from a certain part of the ladle to a ladle. It is formed so that it is in the same direction along the entire path that must pass through the bottom portion 21 to the tap 25. The surface 23 does not have any recess where molten metal remains. The outlet 25 is the lowest point of the path through which the capacity element of the molten metal flows, and the capacity element reaches the outlet without rising again while flowing.

In this embodiment, the tap 25 is shown in FIG.
And near the edge of the contour of the ladle 100, as can be seen from FIGS. The undulations of the upper surface 23 of the bottom 21 are not symmetrical about a vertical central axis and have a fairly tight slope near the tap 25, while the slope is more gradual on the opposite side. These situations are illustrated by the plurality of contour lines 29 on the upper surface 23 of the bottom 21 being shown in FIG. A plurality of contour lines 29 are densely arranged beside the tap 25. This indicates a tight slope. On the other hand, the contour lines are further apart on the opposite side. That is,
There, the slope is less. However, the undulations are oriented in one direction from all directions to the outlet 25 over a 360 ° angle around the axis B of the outlet 25,
It is formed so that the molten metal does not remain anywhere.

The tap 25 (FIG. 3) comprises an outflow nozzle 31 embedded in the monolithic material of the bottom 21 and having an inner diameter 34. A mortar-shaped opening 32 starting from the upper edge of the outflow nozzle 31 is formed in the bottom 21, and the opening extends upward at an opening angle of about 60 °.
When the casting is finished when the melt is at a certain height 37, it is guaranteed that the slag will not be cast together. Therefore, only a small amount of molten metal remains in the ladle 100. The height (horizontal plane) 37 of the mortar-shaped opening 32, that is, the tap hole 2
5 is located above the edge of the horizontal plane 36. The height (vertical length) 35 of the opening 32 is
It has at least the same dimensions as the diameter 34 of the tap 25.

The uniform formation of the upper surface 23 of the bottom 21 according to the contour lines 29 is interrupted by the deflection element 30. This deflecting element is formed by a crest on the upper surface 23 of the bottom 21, the upper surface 33 of this crest being convexly curved and transitioning to the upper surface 23 at the edges around the inclined boundaries 26, 27. The contour of the deflection element 30 is approximately 2 in this embodiment.
It is circular over 40 ° (Fig. 1) and is linearly cut elsewhere. The slanted boundary of the circular portion has the reference numeral 26, and the boundary of the straight portion has the reference numeral 27. The skirt of the inclined boundary 27 is located substantially in the center of the contour of the ladle 100 and on the straight line 28 passing through the axis B of the tap 25.

The gently curved portion of the upper surface 33 of the deflection element 30 may be a spherical portion, but may be another continuous convex curved portion. Due to the thickened part of the bottom 21 made in the region of the deflection element 30 by the bend, it is possible to extend the service life of the ladle 100 until a number of unfavorable depressions are caused by erosion by the hot melt hitting the bottom. Becomes

The shape of the upper surface 23 of the bottom portion 21 is a mold (Schablon
e) manufactured by 40. This mold is formed by a pan-shaped molding made of thick steel plate (Fig. 5). The molding includes an annular vertical side wall 41 and a base plate 42 having a lower surface formed so as to supplement the undulations of the lining 20. The mold 40 can be lowered into the ladle 100 by a crane using a plurality of ropes or chains attached to a plurality of crane eyes 43. There, the mold is prevented from buoyancy.
Then, in the intermediate space between the outer surface of the mold 40 and the inner plate layer 7 of the outer lining 6 and the upper surface of the outer lining 8 of the bottom 21, a flowable refractory material indicated by cross-hatching is provided. , To a height 38 corresponding to the upper boundary of the side 22 of the lining 20. Biasing element 3
To form a zero, the mold 40 has a concave shape.
This shape can be formed by screwing a correspondingly pressed hemisphere 48 onto the mold base plate 42. That is, at the position of the later deflecting element 30, there is an opening 39 in the base plate 42 below the hemisphere 48, which is covered by the hemisphere 48.
The slopes 46, 47 attached to the hemisphere 48 are used to form the sloping boundaries 26, 27. Fixing is accomplished by a plurality of welded squares 44 and a plurality of screws 45 (Fig. 1).
And 5 show only one of each of these)
Or by any other suitable method.

A connecting portion 49 for compressed air is provided at the center of the hemispherical portion 48 or at another portion of the base plate 42. This compressed air is introduced between the lower surface of the base plate 42 and the upper surface 23 of the bottom portion 21 after the completion of molding, and supports lifting of the mold 40. This connection 4
9 allows the hemispherical portion 4 to be injected during injection of the flowable refractory material.
The space below 8 can be evacuated. [Brief description of drawings]

FIG. 1 is a plan view of a ladle for molten steel whose lining is completed.

2 is a vertical cross-sectional view of the upright ladle taken along the line II-II in FIG.

3 is a corresponding sectional view of the lower part of the ladle, along the line III-III in FIG. 1;

FIG. 4 is a corresponding cross-sectional view along the line IV-IV of FIG.

5 is the line II-I of FIG. 1 during the formation of the bottom by the mold.
It is a longitudinal cross-sectional view of the lower part of the ladle corresponding to I.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Löbemeyer, Dieter, Federal Republic of Germany D-46562 Forerde, Alexander Straße 115 (56) Reference JP-A-11-47917 (JP, A) JP-A-9- 52170 (JP, A) JP 3-169473 (JP, A) JP 2-127963 (JP, A) JP 9-174230 (JP, A) JP 5-92242 (JP, A) Japanese Utility Model Publication No. 2-81753 (JP, U) Japanese Patent Publication No. 51-8608 (JP, B2) US Patent 5393703 (US, A) US Patent 4746102 (US, A) US Patent 2472456 (US, A) International Publication 92 / 20479 (WO, A1) European patent application publication 826446 (EP, A 1) European patent application publication 184634 (EP, A 1) European patent application publication 105795 (EP, A 2) (58) (Int.Cl. ^7, DB name) B22D 41/08 B22D 41/00 B22D 41/02

Claims (7)

(57) [Claims] 1. A pan-shaped housing (1) having a bottom (2) and a side wall (3) which is upright during operation and which is made of a steel plate and is open upward, and an inner surface of the housing (1). A cover, a refractory lining for defining an internal space of the housing (1) for containing the molten metal, the outlet for the molten metal being provided in this lining and at the bottom (21) of the housing (1). Lining with a sprue (25),
The upper surface (23) of the bottom portion (21) of the lining is located at any surface passing through the vertical axis (B) extending to the center of the tap (25).
And a refractory deflection element (30) in the sprue region having a convexly curved top surface (33), the bottom portion (21) of the lining being of integral fire resistance. A container for molten metal for metallurgy, especially a ladle for molten steel, made of a conductive material. 2. The upper surface (3) of the deflection element (30).
3. The container according to claim 1, wherein 3) is formed by a gentle spherical curved portion. 3. The bottom (2) of the lining (20).
1) is a hot water outlet nozzle (3) in the area of the hot water outlet (25).
1) A mortar-shaped opening (32) is formed that extends from the upper edge at an opening angle of 30 ° to 90 °, and the height (35) of this opening is at least the inner diameter of the tap nozzle (31) ( 34) Corresponding to 34), the container according to claim 1 or 2. 4. The remainder of the melt is above the upper edge of the tap (25) at the height (35) of the opening (32) corresponding to the diameter (34) of the tap nozzle (31). The casting method using a container according to any one of claims 1 to 3, wherein the molten metal is cast at the end of the casting until it stays in place. 5. The mold is composed of a steel plate mold body having a shape of a pot having a short length and an open upper portion, and the mold body can be hung by a crane and lowered to the container, and the base plate (42) ) Has a relief corresponding to the top surface (23, 33) of the bottom portion (21) of the lining (20). Mold for manufacturing the bottom (21) in a container of. 6. The mold (40) comprises the deflection element (3).
0) has an opening (39) corresponding to the contour of this deflection element, which opening is connected to the base plate (42) of the mold (40) at the edge of the opening (39). Mold according to claim 5, characterized in that it is covered by a possible curved hemisphere (48). 7. The bottom portion (42, 48) of the mold comprises:
A connection (4) for a fluid pressure medium supply conduit for supporting removal of the mold (40) from the bottom (21) of the lining (20) upon removal from the mold.
9) is provided, The mold according to claim 5 or 6.