JP2600774Y2 - Precast blocks for containers for molten metal - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a refractory mounted on the bottom of a container for molten metal such as a ladle for steel making, in particular, on a portion (so-called "hot water") hit by molten metal falling at the start of molten metal injection. It relates to a precast block made of material.

[0002]

2. Description of the Related Art A refractory lining of a container for molten metal is generally made of a brick or an amorphous refractory material. Precast blocks may be used to withstand the impact. After the precast block is installed at the bottom of the ladle, an irregular-shaped refractory material such as a castable refractory material is poured around the precast block to fix the precast block. As shown in FIGS. 9 and 10, the conventional precast block has a flat shape on both sides and bottom except for the raised top. Therefore, installation on the bottom of the ladle must be performed with a wire rope or the like slung, and the support is unstable and lacks safety, and a considerable space is required for releasing the sling. It was difficult to install near the pot wall. Furthermore, when the precast block is fixed to the bottom of the ladle, the irregular refractory material flows into the entire surrounding area.However, due to the difference in the material and shrinkage of the precast block and the irregular refractory material, melting into the gap at the boundary There has been a problem that metal intrusion (so-called metal ingot) is likely to occur, causing local melting and cracking.

[0003]

SUMMARY OF THE INVENTION The present invention solves these problems of the prior art, and enables safe and easy support during installation and transportation. After fixing to a container for molten metal, an amorphous refractory material is provided. It is an object of the present invention to provide a precast block capable of preventing the occurrence of a bullion, local erosion, cracks, and the like at a boundary between the two.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to provide a precast block made of a refractory material which is mounted on the bottom of a container for molten metal, and has a flat shape as a whole, and a flat portion at the center of the upper surface. An inclined portion extending downward from the flat portion toward the peripheral edge, and a concave portion is formed on the side surface for locking at the time of transport, extending over the entire periphery, and the concave portion is fixed to the bottom portion.
This is achieved by a precast block characterized in that the upper surface is slightly upwardly inclined radially outward so as not to form an air pocket when filling the irregular-shaped refractory material .

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a plan view of the precast block according to the present invention, and FIG. 2 is a front view of the precast block shown in FIG. As shown in FIGS. 1 and 2, the precast block 1 has a flat rectangular shape with rounded four corners. The upper surface has a substantially circular flat hot water contact surface 2 formed at the center, and is inclined downward from the hot water contact surface 2 toward the periphery. A concave portion 3 extending over the entire circumference is formed on the side surface. As shown in detail in FIG.
Has a depth that allows the hook 4 of the transport crane to be locked , and the upper surface thereof is filled with irregular refractory material to be fixed to the bottom.
It is inclined slightly upward toward the outside in the radial direction so as not to form an air pocket when filling .

[0006] The precast block is cast, for example, from an alumina castable refractory material and dried at a maximum of 400 ° C for 48 hours after curing.

[0007] In manufacturing a container for molten metal, FIG.
As shown in (1), a permanent wear 9 (iron plate) is first applied to the bottom of the ladle, and a permanent brick 10 is installed so as to entirely cover the permanent wear 9. The precast block 1 is installed on a permanent brick 10 hung on a hook of a crane. In the vicinity of the precast block 1, a tuyere 8 which is an insertion port of a nozzle (not shown) for passing molten metal downward is provided. After the precast block 1 is installed, to fix the precast block 1, as shown in FIG. 4, a brick 5 is installed to the vicinity of the precast block 1, and an irregular refractory material 6 is formed around the precast block.
Pour in. The amorphous refractory material 6 is made of alumina spinel or the like, and is heated and dried after curing.

The illustrated example is a ladle for receiving molten steel from a steelmaking converter, whose main dimensions are as follows.

Outer diameter of ladle: 4550 mm Height of ladle: 4300 mm Length and width of precast block: 1700 mm Outer diameter of hot water contact part: 1000 mm If the inclination angle of the upper surface of the concave portion is large, hook locking is insufficient. On the contrary, if the diameter is made smaller, air may remain in the concave portion and the irregular refractory material may not be easily filled.

The entire shape of the precast block and the shape of the concave portion can be various. As shown in FIG. 7 or FIG. 8, the inner contour of the concave portion (the portion from the outer peripheral line to the broken line) is formed in a circular shape. The formation can more reliably prevent the irregular-shaped refractory material from cracking after curing or during use. This is considered to be because the distortion generated between the precast block 1 and the irregular-shaped refractory material 6 in the concave portion was dispersed in the circumferential direction by the circular shape.

[0011]

[Effect of the invention] The precast block according to the invention is:
Since a concave part is formed on the side surface, transport,
At the time of installation, a hook such as a crane is engaged with the concave portion, so that it can be safely and easily supported. In addition, the work space for releasing the support after the installation is small because of the support by the hook, and the installation of the molten metal container in the vicinity of the peripheral wall becomes possible. As a result, the amount of the irregular-shaped refractory material to be filled between the precast block and the peripheral wall of the container is small, and the amount of shrinkage due to the hardening thereof is also small, so that the gap between the precast block and the precast block is less likely to occur. Also, the upper surface of the recess is radially outward.
Because it is slightly upwardly inclined toward
Can be prevented from being trapped in the air during filling. Further, since the recess is formed over the entire circumference, the bonding area at the boundary between the precast block and the refractory material is large. Therefore, a gap is unlikely to be formed after the mounting, and it is possible to prevent the occurrence of a metal ingot, local erosion and cracks resulting therefrom. In addition, even if a gap is formed due to long-term use or the like, the progress of the bullion is prevented by the step of the concave portion, and as a result, extremely excellent durability is obtained.

[Brief description of the drawings]

FIG. 1 is a plan view showing a precast block according to the present invention.

FIG. 2 is a front view of the precast block shown in FIG.

FIG. 3 is an enlarged view showing a part of the periphery of the precast block shown in FIG. 1;

FIG. 4 is a cross-sectional view showing a state in which an irregular-shaped refractory material is poured around the precast block shown in FIG.

FIG. 5 is a sectional view showing a state in which the precast block according to the present invention is installed at the bottom of the ladle;

FIG. 6 is a plan view of the precast block shown in FIG.

FIG. 7 is a plan view showing another example of the precast block according to the present invention.

FIG. 8 is a plan view showing still another example of the precast block according to the present invention.

FIG. 9 is a plan view showing a conventional precast block.

FIG. 10 is a front view of the precast block shown in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Precast block 2 Hot water contact surface 3 Recess 4 Hook 5 Bricks 6 Irregular refractory material 7 Ladle 8 Tuyere 9 Permanent wear 10 Permanent brick

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) F27D 1/00-1/18 B22D 41/02

Claims (2)

(57) [Scope of request for utility model registration] 1. A precast block made of a refractory material to be mounted on the bottom of a container for molten metal, having a flat shape as a whole, and having a flat portion at the center of an upper surface and extending downward from the flat portion to a peripheral edge. A concave portion for locking at the time of transport extending all around the side surface, and the concave portion is filled with irregular refractory material to be fixed to the bottom portion.
A precast block characterized in that the upper surface is inclined slightly upward toward the outside in the radial direction so as not to form an air pocket. 2. The inclination angle of the upper surface of the concave portion is 5 degrees to 15 degrees.
2. The pre-cas as claimed in claim 1, wherein
Block.