DE102004005739A1 - Continuous casting mold for liquid metals, in particular for steel materials - Google Patents

Abstract

Continuous casting mold, especially for steel is made up of wide (4) and narrow (5) plates which form its walls. These have coatings (8) of a high melting point metal or refractory material on the inside. The corners (10) where the plates meet are protected by narrow strips of material (12) which extend over the edges (5a) of the narrow plates.

Description

The The invention relates to a continuous casting mold for liquid metals, in particular for liquid steel materials, with a pouring room for casting formats, the from broadside surfaces and narrow side surfaces formed or also have another polygonal Eingießraum and on the hot side with a high-melting, metallic protective layer or refractory layer are provided.

Such a continuous casting mold for the production of thin slabs or sheets is from the DE 43 37 399 C2 known. This continuous casting mold consists of at least downwardly converging, liquid-cooled, metallic longitudinal walls (broad side plates) and two narrowing the strand width, partially coated with a refractory material on the Kokilleninnenseite (hot side) narrow side walls, the narrow side walls are slidably disposed between the longitudinal side walls for width adjustment of the casting space. The refractory material consists of boron nitride and is arranged above the narrowest Kokillenquerschnitts to the pouring of the mold. The narrow side wall has a V-shaped recess which is filled by means of a plate made of boron nitride. This plate is formed starting from the upper edge of the mold with a bead-shaped, extending in the casting cross-section thickening, which extends to below the mold level in the mold. Such a design is attributed to the smallest possible wettability by the steel in terms of boron nitride. Furthermore, this mold can be used together with conventional len immersion nozzles, so no shallow immersion spouts. This should make it possible to increase the number of sequence casts. The immersion nozzles also allow horizontal or only slightly inclined side spouts, which can cause better mold filling of the mold and a quiet bathroom mirror.

In contrast, aspires the invention a homogenization of Heat flows from the casting strand on the mold plates and within the cast strand format from the edges and side surfaces at.

Of the Invention is based on the object, while increasing the service life for narrow side surfaces or Narrow side plates this homogenization of heat flows between To achieve edges, corners and wide or narrow surfaces.

The Asked object is inventively achieved in that the protective layer of the refractory metal or the refractory material in the corner between wide side plates and narrow side plates on the narrow side surface with its outer edge finally, in a least over a mold height range extending, relatively narrow strip is applied. Thereby becomes the heat flow from the cast strand to the mold surface or chill plate reduced. This creates the further advantage that the temperature of the cast strand format edge across from the cast strand format center area areas less decreases. The resulting from lower temperature differences Tensions are reduced and the risk of edge cracks on the cast strand is reduced. Another advantage is that due to the nature of the coating, which may, for example, consist of nickel, the service life of the narrow side plates elevated becomes. Furthermore can on material for the protective layer can be saved.

In Embodiment of the invention is provided that the width of the Strip is increasingly running in strand direction. This is the protective layer at Kokillenaustritt wider than at Kokilleneintritt. This training is in view of the growing strand shell and the two-dimensional Heat transfer advantageous in the edge of the casting strand.

A further consequences, to regulate the heat flows, i.e. to even out, is to that the relatively narrow strip of refractory metal or Refractory material in its thickness at the level of the mold is rising downwards.

To a further homogenization of the heat flows from Gießstrang outer circumference to the mold in that the relatively narrow strip in its thickness in the direction to the middle of the narrow side surface thinner is designed. This is the protective layer in the edge the thickest and considered the two-dimensional heat transfer of a Edge.

A full Influencing the cast strand formats continues to take place in that the strip at the Kokilleneintrittskante begins and runs to Kokillenaustrittskante.

For different Gießformate Corners and edges are to be provided in large numbers. In this case it is advantageous that within the polygonal Eingießraums corner areas and / or projecting edges with the relatively narrow strip are provided from the protective layer. For example. Can the twelve corners and edges of a beam-blank mold (Preliminary-casting format) to reduce the heat transfer be coated.

In the drawing are embodiments of Invention, which are explained in more detail below.

It demonstrate:

1 a top view of the Eingießraum a slab mold,

2 a view against the hot side of a Kokillenschmalseitenplatte in the direction "A" according to 1 and

3 a plan view of a pre-profile continuous casting mold.

In 1 is an example of a continuous casting mold 1 with a pouring room 2 for a casting format 3 a slab or block casting strand. In principle, the invention can be applied to billet, billet, block, pre-profile, thin slab and slab casting formats 3 be applied, wherein at least two opposite broad side plates 4 (Broadside surfaces) and two opposite narrow side plates 5 (Narrow side surfaces) are assumed. In the pouring room 2 By cooling, the strand shell surrounding the cast strand is formed 3a ,

A protective layer 8th made of refractory metal or refractory material 9 is in the corner 10 between the broadside plates 4 and narrow side plates 5 on the narrow side surface 5 , with the outer edges 5a concluding on one side, in one above the mold height 11 extending, relatively narrow strip 12 on the hot side 7 applied, which is usually done in a vacuum via an electron beam method. The stripe 12 closes on its surface with the inner surface of the Eingießraums 2 from.

The width 12a of the strip 12 is in each case in strand direction 13 increasingly executed ( 2 ).

Furthermore, the relatively narrow strip 12 made of refractory metal 9 or refractory material) in its thickness 12b at the level of the mold 1 applied downward. The fat 12b (perpendicular to the plane) is on average about 0.2 to 06 mm.

By contrast, the relatively narrow strip 12 in his thickness 12b towards the middle 14 the narrow side surface 5 made thinning out.

For economic reasons, the narrow strip 12 on a mold height range 11 be limited. Its full effect unfolds the strip 12 when at the mold inlet edge 15 begins and at the Kokillenaustrittskante 16 ends.

In 3 is a plan view of a pre-profile continuous casting mold 1a being shown, being inside the polygonal pouring space 2 corner areas 10 and / or projecting edges 17 with the relatively narrow stripes 12 that's out of the layer 8th exists, are provided.

1

continuous casting for slab format

1a

Primary profile casting mold

2

mold space

3

casting format

3a

strand shell

4

Broadside plate / broadside surface

5

Narrow side plate / edge face

5a

outer edge

6

polygonal mold space

7

hot side

8th

protective layer

9

refractory Metal (or fire test material)

10

corner

11

Mold height range

12

relative narrow strip

12a

width of the strip

12b

thickness of the strip

13

Strand running direction

14

center the narrow side surface

15

Kokilleneintrittskante

16

Kokillenaustrittskante

17

edge of the format section

Claims (6)

Continuous casting mold ( 1 ) for liquid metals, in particular for liquid steel materials, with a pouring area ( 2 ) for casting formats ( 3 ) consisting of broadside plates ( 4 ) and narrow side plates ( 5 ) or another polygonal pouring area ( 6 ), and on the hot side ( 7 ) with a high-melting metallic protective layer ( 8th ) or refractory layer, characterized in that the protective layer ( 8th ) from the refractory metal ( 9 ) in the corner area ( 10 ) between wide side plates ( 4 ) and narrow side plates ( 5 ) on the narrow side surface ( 5 ) with its outer edge ( 5a ), at least over a mold height range ( 11 ), relatively narrow strips ( 12 ) is applied. Continuous casting mold according to claim 1, characterized in that the width ( 12a ) of the strip ( 12 ) in strand direction ( 13 ) is increasingly executed. Continuous casting mold according to claim 1, characterized in that the relatively narrow strip ( 12 ) of refractory metal ( 9 ) or refractory material in its thickness ( 12b ) at the level of the mold ( 1 ) is running downwards. Continuous casting mold according to one of claims 1 to 3, characterized in that the relatively narrow strip ( 12 ) in its thickness ( 12b ) towards the center ( 14 ) of the narrow side surface ( 5 ) is designed thinning out. Continuous casting mold according to one of claims 1 to 4, characterized in that the strip ( 12 ) at the Kokilleneintrittskante ( 15 ) and up to Kokillenaustrittskante ( 16 ) runs. Continuous casting mold according to one of claims 1 to 5, characterized in that within the polygonal Eingießraums ( 2 ) Corner areas ( 10 ) and / or projecting edges ( 17 ) with the relatively narrow strip ( 12 ) from the protective layer ( 8th ) are provided.