DE1271913B - Steel mill wear material - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

B22d

German class: 31 b2- 35/04

Number: 1271913

File number: P 12 71 913.0-24 (St 17363)

Filing date: January 19, 1961

Open date: 4th July 1968

The invention relates to a steel mill wear material in the form of two concentric Shells made of ceramic material arranged in relation to one another, of which steel flows through the inner one will.

From the German patents 454536 and 529 899 steel mill wear material is in the form known from two concentrically arranged shells made of ceramic material, of which the inner one is traversed by the steel. The two-part or three-part design of these shells is intended for a Breakage of the same does not prevent the liquid steel from escaping, rather the channel stone should move on the German patent 454 536 be cheap to manufacture, including the inner tube made of a high quality Material is made, while the outer jacket is made of an inferior material. The production of this sewer stone from two different materials and its special structure, in which the inner core tube protrudes over the outer jacket, require a separate production of both parts. the Separate production of both parts is not only cumbersome and expensive, but also disadvantageous in that when the tube of the soul and the mantle do not close tightly at all points. In the extrusion process Ceramic moldings produced occur in particular through the cutting and the subsequent Dry up significant dimensional deviations and deformations, which then occur when assembling the prevent individual parts from resting against the surfaces. For this reason, the significant pressure forces and thermal stresses acting on the inner core tube are not directly can also be transmitted to the outer tube, so that the inner tube is subjected to an overload is. The likelihood that the inner tube will crack and as a result of it suddenly leaking liquid steel, even the outer tube gets a crack in the same place, is very large.

In the case of the channel stones according to German patent specification 529 899, it is also not intended that the core tube and the jacket close tightly so that in the event of a breakage of the core tube to prevent the liquid steel from escaping through the jacket pipe. Rather, both tubes will Manufactured separately, so that casing and core pipes are separated from one another on the finished sewer stones and remain displaceable against each other. As already mentioned, this has the consequence that both Do not enclose pipes tightly, so that forces are transmitted from the inner pipe to the outer one Pipe is practically impossible. Otherwise, the steel mill will wear material

Applicant:

Rasselstein Aktiengesellschaft, 5450 Neuwied

Named as inventor:

Albert Schlueter, 5450 Neuwied;

Gerhard Horn, 5451 Altwied

Production is also more expensive due to the separate manufacture of the inner and outer tubes.

The object of the invention is to provide a steel mill wear material of the type mentioned at the beginning To create a design in which, on the one hand, the escape of liquid steel and, on the other hand, the penetration reliably prevents impurities in the liquid steel in the event of one of the pipes breaking is; furthermore, the risk of breakage should be considerably reduced.

According to the invention, this object is achieved in that they are common in a manner known per se Shells produced in one operation by extrusion enclose so tightly that they adhere to touch all points of their inner or outer surfaces and that in the surfaces on which they touch, longitudinal grooves are provided, these longitudinal grooves at angular intervals and on the mutually contacting surfaces are mutually offset. In contrast to the previously known Sewer stones according to the German patents is therefore the wear material according to the invention manufactured by extrusion in one operation, so that the shells are much closer and more accurate enclose than would be possible with separate production. Baked when the ceramic material is sintered the two shells with each other on their surfaces in contact, but with the The homogeneity of the material remains interrupted. In this way it is achieved that the shells are tight enclose and touch at all points, so that a transfer of forces from the inner shell to the outer is possible. So the outer shell is effective in serving the inner shell to everyone To support points, whereby the risk of breakage of the inner shell is greatly reduced. Through the at the contacting surfaces of the shells provided longitudinal grooves, the longitudinal grooves of the inner and outer shell are offset from one another, it is achieved that the shells, if they

809 568/456

break, break at very specific staggered points. The one from the inner shell on one As a result, liquid steel escaping from the fracture runs between the two surfaces of the shells along and could then only emerge at an offset fracture point in the outer shell. on however, it will freeze on this path, similar to the subject of German patent specification 529 899 described. In contrast to the subject matter of the invention, however, the channel stone according to the ίο called German patent specification of liquid steel in the event of a break in the inner tube and the outer one Casing pipe emerge from the sewer stone, since no predetermined breaking points are provided there. One sees no such predetermined breaking points before, the risk is very great that the inner and the outer tube tears in the same place. It is then also possible that, for example, sand penetrate and the can contaminate liquid steel.

The invention is described below with reference to an embodiment shown in ao of the drawing explained in more detail. It shows

F i g. 1 shows a vertical cross section through a funnel tube according to the invention,

F i g. 2 shows a longitudinal section through the pipe according to FIG. 1 along the line H-II in FIG. 1.

First of all, it should be noted that funnel hats, channel stones, funnel floor stones and the like are also analogous Way can be designed.

In Fig. 1 and 2, 1 denotes a funnel tube made of sintered ceramic. This funnel tube consists of an inner shell 2 and an outer shell 3. If necessary, could also even more shells can be provided. The shells 2 and 3 are arranged concentrically to one another. According to the invention, they enclose in a manner known per se through together in one operation Extrusion-made shells 2, 3 are so tight that they are in all points of their inner and outer Touch surfaces 4 and 5. Furthermore, in the surfaces 4 and S, where they touch, Longitudinal grooves 6 and 7 are provided, these longitudinal grooves at angular intervals and on the touching one another Areas are mutually offset. It is thus avoided that the longitudinal grooves 6 on the outer surface of the inner shell 2 opposite the longitudinal grooves 7 on the inner surface of the outer shell 3 come to rest.

If there is now a crack in the funnel tube - and this is not possible because of the sudden sudden fluctuations in temperature often unavoidable - then such a crack always forms one through one Longitudinal grooves from the weakened area. In Fig. 1 such a crack is shown. It penetrates the inner shell at 8 2 and is based on a longitudinal groove 6. If the crack continues outward, then it forms the continuation in the outer shell is also at a point weakened by a longitudinal groove 7 off, as indicated at 9. The two cracks 8 and 9 are against each other along the circumference of the funnel tube offset, so that no steel escape from the interior of the tube 1 and no sand into the Can penetrate the pipe. It should be noted that the one shown in the drawing, between the Shells 2 and 3 located gap 10 is either extremely narrow or practically nonexistent. When the ceramic material is sintered, the two shells bake on their contact surfaces 4 and 5 with each other, but so little that the homogeneity of the material is not interrupted.

The grooves 6 and 7 are expediently provided with a rounded cross-section. In order to the strength of the notch effect of the grooves is reduced. This is desirable because the grooves are not encourage the occurrence of cracks, but are only intended to determine the location of cracks in advance.

The in Fig. 1 and 2 shown funnel tube is, as already mentioned, produced by the extrusion process. The two shells 2 and 3 from each other are pressed into the ceramic material separating narrow annular gap 10 formed, of which alternating on both sides and offset from one another the longitudinal grooves 6 and 7 go out.

In the preferred embodiment shown, three longitudinal grooves 6 and 7 are provided on each shell 2, 3 offset from one another by 120 °, the longitudinal grooves of one shell 2 being 60 compared to those of the other shell 3 on the mutually contacting surfaces 4 and 5 ° are arranged offset from one another.

Claims (3)

Patent claims: 1. Steelworks wear material in the form of two concentrically arranged shells made of ceramic material, of which the inner one is traversed by steel, characterized in that the shells (2, 3) produced together in one operation by extrusion are so tight enclose that they touch at all points of their inner and outer surfaces (4, 5), and that in the surfaces (4, 5) at which they touch, longitudinal grooves (6, 7) are provided, these longitudinal grooves are arranged offset from one another at angular intervals and on the surfaces in contact with one another. 2. Steel mill wear material according to claim 1, characterized in that the longitudinal grooves (6,7) are provided with a rounded cross-section. 3. Steel mill wear material according to claim 1, characterized in that on each shell (2, 3) three longitudinal grooves (6, 7) offset from one another by 120 ° are provided, the longitudinal grooves of one shell (2) compared to those of the other shell (3) are arranged offset from one another by 60 ° on the surfaces (4, 5) in contact with one another. Considered publications: German Patent Specifications No. 529 S99, 454 536. 1 sheet of drawings 809 568/456 6.68 © Bundesdruckerei Berlin