JP2562502Y2 - Protective structure of refractory for taphole of electric furnace - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection structure for a refractory for a tap hole of an electric furnace in the field of metallurgy, and more particularly, to a tap hole for an electric furnace for stabilizing the operation and extending the life of the refractory for the tap hole. The present invention relates to a structure for protecting refractory materials.

[0002]

2. Description of the Related Art In an EBT electric furnace in which a tap hole of a tap hole is eccentrically mounted on a bottom portion, a refractory for a tap hole is usually constructed by stacking four sleeve bricks. When mounted in the EBT electric furnace, a castable refractory or mortar is filled between the electric furnace main body and the taphole refractory, and a support metal is attached to the lowermost refractory to support it. I have.

A water-cooled cooling structure is usually employed for the support fitting in order to prevent a problem caused by a rise in the temperature of the refractory for tap holes during tapping.

[0004]

[Problem to be Solved by the Invention] In the cooling structure of the water cooling system, under the influence of a high temperature as high as 1500 ° C. at the time of tapping,
There is a large temperature difference between the portion where water enters and the portion where it exits, and this temperature difference naturally affects the refractory for tapholes, and the refractory may fall off due to the hot spooling.

[0005] Since it is the refractory at the bottom of the tap hole that peels off, it is difficult to prevent the molten steel from scattering at the time of tapping and to control the amount of poured steel. Had to be replaced.

[0006] Further, when tap hole refractories for an EBT electric furnace of the same lot are used, but the support bracket is different or the user is different, the tap hole refractory is located at the lowermost end of the tap hole refractory. Peeling occurred. Since the spalled portion is almost the same portion on the inlet side of the cooling water, and shows the same phenomenon, it is considered that there is a problem to be solved in the support fitting for fixing the refractory and the cooling method thereof.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and in order to solve the above problems, an outer peripheral portion of a tap hole refractory at a tapping portion of an electric furnace is provided. In addition, the present invention provides a protective structure for a refractory for tap holes of an electric furnace, wherein a metal fitting for cooling and cooling is attached via a refractory heat insulating material having a refractory degree of 500 ° C. or more and a porosity of 20% or more. is there.

[0008]

According to the present invention, a cooling / receiving member is attached to the outer periphery of a refractory for a tap hole of an electric furnace via a refractory heat insulating material having a refractory degree of 500 ° C. or more and a porosity of 20% or more. As a result, rapid heating from the inside and rapid cooling from the outside of the refractory can be mitigated by the refractory insulation against thermal shocks repeated during tapping, and the refractory is heated Peeling can be prevented and durability can be increased.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. 1 and 2 show an embodiment of the present invention. Electric furnace 1
Is an EBT electric furnace in which a tap hole 2 of a tapping hole is eccentrically mounted on the side of the bottom, and the outer periphery of a refractory 3 forming the tap hole 2 is received via a refractory heat insulating material 4. The fitting 5 is attached.

The taphole refractory 3 is formed by stacking tubular sleeve bricks in a plurality of stages as shown in FIG. 1, and the outer peripheral portion of the lowermost refractory 3 as shown in FIG. The refractory heat insulating material 4 is adhered to the taper portion 6 of the above, and the surroundings are covered and supported by a cooling metal fitting 5.

The refractory heat insulating material 4 uniformly diffuses heat to the refractory 3 against rapid heating applied from the inside at the time of tapping, and responds to rapid cooling applied from the outside via the receiving fitting 5. In this case, the heat transfer amount is reduced and transmitted to the refractory 3 to reduce heat spooling.

Therefore, the fire-resistant heat insulating material 4 needs to have a heat insulating effect at a high temperature, and from the test results, a heat insulating material having a fire resistance of 500 ° C. or more and a porosity of 20% or more is required. If the heat resistance of the heat insulating material is 500 ° C. or less, the heat insulating property at a high temperature cannot be maintained, and the porosity is 20%.
% Or less is not preferable because the heat insulating properties are poor and the above effects cannot be sufficiently exhibited.

[0013] These refractory insulation materials 4 are 1 to 5 mm.
Sheet-like or cotton-like materials such as ceramics, asbestos, and asbestos can be used.

The receiving fitting 5 covers the periphery of the refractory heat insulating material 4 and supports the outer peripheral portion of the refractory 3.
As shown in FIG. 1, a cooling device 7 such as a water-cooled jacket structure is mounted around the device to cool the refractory 3 and protect it from high heat. 8 is an electrode rod.

[0015]

[Example of use] As shown in FIG. 2, a 3 mm thick, 50% porosity asbestos sheet refractory heat insulating material 4 is attached to the taper portion 6 at the bottom of the refractory 3 for tap hole. The EBT electric furnace having a capacity of 50 tons and a tapping temperature of 1580 ° C. was used as a trial, supported by the receiving fitting 5. As a result, the average life was 116 charges for 13 trials, which was a very good result.

In the past example, when the same lot product is used under the same conditions, the number of products is 13 to 116 for 10 products, the average life is 63, the variation is large, and the lower end is also peeled off. Although it often occurred at 10 charges or less, in the case of the present invention, it was possible to prevent peeling off, and there was little variation.

In the above description, the refractory heat insulating material and the receiving metal fitting are attached to the lowermost tapered portion of the lower portion of the refractory for a tap hole. You can also.

Although the EBT electric furnace has been described above, the present invention can be applied to other electric furnaces having a similar tap hole.

[0019]

As described above, in the present invention, the refractories for tapholes of an electric furnace can be uniformly diffused with respect to rapid heating from the inside by a predetermined refractory heat insulating material. It can exhibit the heat insulation effect against rapid cooling from the side, effectively prevent peeling off due to thermal spoiling from repeated thermal shocks, improve durability, and improve the durability of electric furnaces. It can improve the performance.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view of an electric furnace according to an embodiment of the present invention;

FIG. 2 is an enlarged sectional view of a tap hole portion of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electric furnace 2 ... Tap hole 3 ... Refractory 4 ... Refractory insulation material 5 ... Receiving bracket

Claims (1)

(57) [Scope of request for utility model registration] Attachment of a cooling / receiving member to the outer periphery of a tap hole refractory at a tapping hole of an electric furnace through a refractory heat insulating material having a refractory rating of 500 ° C. or more and a porosity of 20% or more. A protective structure for a refractory for a tap hole of an electric furnace, characterized in that: