EP4589023A1

EP4589023A1 - Molten metal vessel

Info

Publication number: EP4589023A1
Application number: EP23907479.2A
Authority: EP
Inventors: Jongwoo YOU; Sanghyun Park
Original assignee: Posco Co Ltd
Current assignee: Posco Holdings Inc
Priority date: 2022-12-19
Filing date: 2023-11-28
Publication date: 2025-07-23
Also published as: EP4589023A4; CN120112663A; JP2025536089A; WO2024136193A1; KR20240095922A

Abstract

Disclosed herein is a molten metal vessel. The molten metal vessel according to an embodiment of the present disclosure includes an outer steel shell layer, a refractory layer laminated inside the outer steel shell layer to form a molten metal receiving space, a heat insulation board layer interposed between the refractory layer and the outer steel shell layer, and a heat insulation coating layer applied to at least one of an outer surface and an inner surface of the outer steel shell layer, wherein the heat insulation coating layer comprises a ceramic-based binder and a plurality of hollow particles.

Description

[Technical Field]

The present disclosure relates to a molten metal vessel capable of minimizing heat loss of molten metal.

[Background Art]

A molten metal vessel is used to contain and transport or process molten metal in a steel mill, and the like, and is also referred to a ladle. Molten metal may be transferred to a tundish for casting in such a vessel, and refining operations, such as temperature control, composition adjustment, impurity removal, degassing, and the like may be performed.
The molten metal vessel needs to minimize heat loss of the molten metal while transporting or processing the molten metal. Accordingly, the molten metal vessel includes an outer steel shell layer and a refractory layer laminated on an inner surface of the steel shell layer to form a receiving space for the molten metal. The refractory layer prevents the heat of the molten metal from being transferred to the steel shell layer, thereby preventing a rapid drop in the temperature of the molten metal.
As a method of improving the heat insulation of the molten metal vessel, it is possible to increase the thickness of the refractory layer or to lower the thermal conductivity by adjusting the composition of the refractory layer. However, the method of increasing the thickness of the refractory layer has the disadvantage of excessively increasing the weight of the molten metal vessel and reducing the molten metal receiving space. The method of lowering the thermal conductivity by adjusting the composition of the refractory material has also reached the limit of technological development, hindering further technological advancements.

[Disclosure]

[Technical Problem]

An embodiment of the present disclosure provides a molten metal vessel capable of minimizing heat loss from molten metal by improving the heat insulation effect without significantly increasing the volume of the vessel.

[Technical Solution]

According to an aspect of the present disclosure, a molten metal vessel includes an outer steel shell layer, a refractory layer laminated inside the outer steel shell layer to form a molten metal receiving space, a heat insulation board layer interposed between the refractory layer and the outer steel shell layer, and a heat insulation coating layer applied to at least one of an outer surface and an inner surface of the outer steel shell layer, wherein the heat insulation coating layer comprises a ceramic-based binder and a plurality of hollow particles.
According to an aspect of the present disclosure, a molten metal vessel includes an outer steel shell layer, a heat insulation board layer laminated to an inner surface of the outer steel shell layer, an inner steel shell layer laminated to an inner surface of the heat insulation board layer, a refractory layer laminated to an inner surface of the inner steel shell layer to form a molten metal receiving space, and a heat insulation coating layer applied to at least one of an outer surface of the outer steel shell layer, the inner surface of the outer steel shell layer, an outer surface of the inner steel shell layer, and the inner surface of the inner steel shell layer, wherein the heat insulation coating layer comprises a ceramic-based binder and a plurality of hollow particles.
The heat insulation board layer may include magnesium oxide (MgO) and silicon dioxide (SiO₂) as a component.
The ceramic-based binder may include at least one selected from the group consisting of silicon (Si), aluminum (Al), titanium (Ti), zirconium (Zr), calcium (Ca), magnesium (Mg), yttrium (Y), and cerium (Ce).
The plurality of hollow particles may include at least one of silicon dioxide (SiO₂), aluminum oxide (Al₂O₃), and magnesium oxide (MgO) particles having hollow portions.
The molten metal vessel may further include a plurality of fasteners configured to connect and bind the inner steel shell layer and the outer steel shell layer.
The plurality of fasteners may include a plurality of fastening bolts binding the inner steel shell layer and the outer steel shell layer in a state of penetration through the heat insulation board layer 223, and pressing the inner steel shell layer and the outer steel shell layer against the heat insulation board layer by the binding.

[Advantageous Effects]

The molten metal vessel according to various embodiments of the present disclosure may further include the heat insulation board layer and the heat insulation coating layer in addition to the refractory layer, so that the heat insulation effect may be significantly improved compared to the conventional method, thereby minimizing heat loss of the molten metal during the transfer and handling of the molten metal. In addition, compared to the conventional method of increasing the thickness of the refractory layer, a good heat insulation effect without significantly increasing the volume or weight of the vessel may be achieved.

[Description of Drawings]

FIG. 1 is a cross-sectional view of a molten metal vessel according to an embodiment of the present disclosure.
FIG. 2 is a detailed view of portion A of FIG. 1.
FIG. 3 shows a variation of a main portion of the molten metal vessel according to an embodiment of the present disclosure.
FIG. 4 shows a comparison of the heat insulation effect of a heat insulation coating layer of the molten metal vessel according to an embodiment of the present disclosure with a conventional one.
FIG. 5 shows a comparison of the heat insulation effect of a heat insulation board layer of the molten metal vessel according to an embodiment of the present disclosure with a conventional one.
FIG. 6 is a cross-sectional view of a main portion of a molten metal vessel according to an embodiment of the present disclosure.

[Mode for Invention]

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following embodiments are presented to fully convey the spirit of the present disclosure to those skilled in the art to which the present disclosure pertains, and are not limited to those shown herein, but may be embodied in other forms. The drawings may omit figures not pertinent to the description in order to clarify the present disclosure, and the sizes of configurations may be exaggerated for the purpose of illustration.
FIG. 1 is a cross-sectional view of a molten metal vessel according to an embodiment of the present disclosure. As shown in the drawing, a molten metal vessel 100 may include a bottom portion 101 and a cylindrical sidewall portion 102 extending upwardly from a perimeter of the bottom portion 101. An opening 103 in an upper side of the sidewall portion 102 may be opened and closed by a separate cover 105.
The bottom portion 101 and the sidewall portion 102 may be integrally connected and together form a receiving space 110 capable of receiving molten metal. The molten metal may be introduced or discharged through the upper opening 103. Such a molten metal vessel 100 may contain molten metal therein and be transported to a subsequent process such as a converter, a tundish, or the like, and may be used for refining operations such as temperature control, composition adjustment, impurity removal, and degassing while containing the molten metal.
Since the molten metal vessel 100 may receive and process molten metal of 1300°C or higher, it is required to have heat insulation to maintain the temperature of the molten metal, heat resistance to withstand high temperatures, and rigidity for stable transportation. To realize such requirements, the bottom portion 101 and the sidewall portion 102 of the molten metal vessel 100 may include an outer steel shell layer 121, a refractory layer 122, a heat insulation board layer 123, and a heat insulation coating layer 124, as shown in FIGS. 1 and 2.
The outer steel shell layer 121 may be an outer structure that maintains the appearance of the molten metal vessel 100. The outer steel shell layer 121 may be made of rolled steel for structural use having a rigidity capable of withstanding impacts that may be applied from the outside during the transportation and handling of the molten metal vessel 100, as well as the load and pressure of the molten metal.
The refractory layer 122 may be laminated to an inner side of the outer steel shell layer 121 to form the receiving space 110 for the molten metal. The refractory layer 122 may be formed by stacking refractory bricks in multiple layers. The refractory layer 122 may have heat resistance and heat insulation to withstand high-temperature molten metal, and may be made of Al₂O₃-SiO₂-based refractory bricks or Al₂O₃-SiC-C-based refractory bricks.
The heat insulation board layer 123 may be installed between the outer steel shell layer 121 and the refractory layer 122 such that an outer surface thereof is in contact with an inner surface of the outer steel shell layer 121, and an inner surface thereof is in contact with an outer surface of the refractory layer 122. The heat insulation board layer 123 may be laminated to the inner surface of the outer steel shell layer 121, and the refractory layer 122 may be laminated to the inner surface of the heat insulation board layer 123.
The heat insulation board layer 123 may increase heat insulation and thus reduce heat loss of the molten metal. The heat insulation board layer 123 may be made of a material containing magnesium oxide (MgO) and silicon dioxide (SiO₂) in a panel form and then laminated to the inner surface of the outer steel shell layer 121. The heat insulation board layer 123 may have a thermal conductivity coefficient in the range of 0.1 to 1.0 W/m²K, low reactivity with water, and strength to withstand the ferrostatic pressure of the molten metal.
The heat insulation coating layer 124 may be applied to the outer surface of the outer steel shell layer 121 as shown in FIG. 2, or to the inner surface of the outer steel shell layer 121 as shown in FIG. 3. Alternatively, the heat insulation coating layer 124 may be provided on both the outer and inner surfaces of the outer steel shell layer 121.
The heat insulation coating layer 124 may include a ceramic-based binder and a plurality of hollow particles.
The plurality of hollow particles may include at least one of silicon dioxide (SiO₂), aluminum oxide (Al₂O₃), and magnesium oxide (MgO) particles having hollow portions.
The ceramic-based binder may be a material contained in the heat insulation coating layer 124, and may be adhered or bonded to the surface of the outer steel shell layer 121, and serve to bind and coat the plurality of hollow particles dispersed therein.
The ceramic-based binder may include at least one selected from the group consisting of silicon (Si), aluminum (Al), titanium (Ti), zirconium (Zr), calcium (Ca), magnesium (Mg), yttrium (Y), and cerium (Ce), which may withstand high temperatures of 1000°C or higher.
The heat insulation coating layer 124 may be applied to the surface of the outer steel shell layer 121 with a thickness of 1 to 5 mm to provide excellent heat insulation effect while maintaining a stable state. Air spraying may be used for the application to maintain uniformity of the thickness.
The heat insulation coating layer 124 may provide an excellent heat insulation effect by including a plurality of silicon dioxide (SiO₂) particles having hollow portions. The heat insulation coating layer 124 may have a thermal conductivity in the range of 0.01 to 0.1 W/m²K, which is similar to that of air, and have heat resistance to withstand temperatures of 1000°C or higher, thereby maintaining a stable application state even during the process of handling molten metal.
FIG. 4 shows a comparison of the heat insulation effect of the heat insulation coating layer 124 with the conventional one. In FIG. 4, graph B shows the temperature change trend of the molten metal contained in the molten metal vessel to which the heat insulation coating layer 124 is applied, and graph C shows the temperature change trend of the molten metal contained in the molten metal vessel to which the heat insulation coating layer 124 is not applied. As shown in FIG. 4, the molten metal vessel to which the heat insulation coating layer 124 is applied may improve the heat insulation effect to minimize heat loss, thereby reducing the temperature drop of the molten metal compared to the conventional method.
FIG. 5 shows a comparison of the heat insulation effect of the heat insulation board layer 123 with the conventional one. In FIG. 4, graph D shows the temperature change trend of the molten metal contained in the molten metal vessel to which the heat insulation board layer 123 is applied, and graph E shows the temperature change trend of the molten metal contained in the molten metal vessel to which the heat insulation board layer 123 is not applied. As such, the molten metal vessel to which the heat insulation board layer 123 is applied may also improve the heat insulation effect to minimize heat loss, thereby reducing the temperature drop of the molten metal compared to the conventional method.
As described above, the molten metal vessel 100 of an embodiment of the present disclosure may include the heat insulation board layer 123 and the heat insulation coating layer 124 in addition to the refractory layer 122, so that the heat insulation effect may be significantly improved as compared to the conventional method, and thereby, the heat loss of the molten metal may be minimized during the transporting and handling of the molten metal. In addition, compared to the conventional method of increasing the thickness of the refractory layer, a good heat insulation effect may be achieved without significantly increasing the volume or weight of the vessel.
FIG. 6 is a cross-sectional view of a main portion of a molten metal vessel 200 according to an embodiment of the present disclosure.
The molten metal vessel 200 of an embodiment may further include an inner steel shell layer 226 and a plurality of fasteners 227. Specifically, the present embodiment may include an outer steel shell layer 221, a heat insulation board layer 223 laminated to an inner surface of the outer steel shell layer 221, an inner steel shell layer 226 laminated to an inner surface of the heat insulation board layer 223, a refractory layer 222 laminated to an inner surface of the inner steel shell layer 226 to form a molten metal receiving space 210, and a heat insulation coating layer 224 applied to at least one of an outer surface of the outer steel shell layer 221, the inner surface of the outer steel shell layer 221, an outer surface of the inner steel shell layer 226, and the inner surface of the inner steel shell layer 226.
In the present embodiment, the outer steel shell layer 221, the heat insulation board layer 223, and the refractory layer 222 may be configured in the same manner as in the embodiment described above, and the heat insulation coating layer 224 may also be provided with the same composition, with the application position being different.
When manufacturing the molten metal vessel 200 of the present embodiment, the outer steel shell layer 221, the heat insulation board layer 223, the inner steel shell layer 226, and the refractory layer 222 may be sequentially laminated. In addition, the heat insulation coating layer 224 applied to the surfaces of the outer steel shell layer 221 and the inner steel shell layer 226 may also be applied in advance before assembling them.
FIG. 6 illustrates an example in which the heat insulation coating layer 224 is applied to the outer surface of the outer steel shell layer 221 and the inner surface of the inner steel shell layer 226, but the heat insulation coating layer 224 is not limited thereto, and may be selectively applied to at least one of the outer surface of the outer steel shell layer 221, the inner surface of the outer steel shell layer 221, the outer surface of the inner steel shell layer 226, and the inner surface of the inner steel shell layer 226, or all surfaces of the outer steel shell layer 221 and the inner steel shell layer 226, depending on the required degree of heat insulation.
The plurality of fasteners 227 may increase the rigidity of the molten metal vessel 200 by connecting the inner steel shell layer 226 and the outer steel shell layer 221 at positions spaced apart from each other. As shown in FIG. 6, the plurality of fasteners 227 may include a plurality of fastening bolts 228 binding the inner steel shell layer 226 and the outer steel shell layer 221 in a state of penetration through the heat insulation board layer 223, and pressing the inner steel shell layer 226 and the outer steel shell layer 221 against the heat insulation board layer 223 by the binding.
Here, the fastening bolts 228 may be used as an example of the fastener 227, but the shape of the fastener 227 is not limited thereto. The fastener 227 may be a method of welding the inner steel shell layer 226 and the outer steel shell layer 221 to a separate metal structure while the separate metal structure is positioned between the inner steel shell layer 226 and the outer steel shell layer 221.
The molten metal vessel 200 of the present embodiment may further include the inner steel shell layer 226 and the plurality of fasteners 227, and the heat insulation coating layer 224 may be is formed not only on the outer steel shell layer 221 but also on the inner steel shell layer 226. Accordingly, the rigidity of the molten metal vessel 200 may be further increased and the heat insulation effect may be further improved compared to the embodiment.

Claims

A molten metal vessel, comprising:
an outer steel shell layer;

a refractory layer laminated inside the outer steel shell layer to form a molten metal receiving space;

a heat insulation board layer interposed between the refractory layer and the outer steel shell layer; and

a heat insulation coating layer applied to at least one of an outer surface and an inner surface of the outer steel shell layer;

wherein the heat insulation coating layer comprises a ceramic-based binder and a plurality of hollow particles.
A molten metal vessel, comprising:
an outer steel shell layer;

a heat insulation board layer laminated to an inner surface of the outer steel shell layer;

an inner steel shell layer laminated to an inner surface of the heat insulation board layer;

a refractory layer laminated to an inner surface of the inner steel shell layer to form a molten metal receiving space; and

a heat insulation coating layer applied to at least one of an outer surface of the outer steel shell layer, the inner surface of the outer steel shell layer, an outer surface of the inner steel shell layer, and the inner surface of the inner steel shell layer;

wherein the heat insulation coating layer comprises a ceramic-based binder and a plurality of hollow particles.
The molten metal vessel of claim 1 or 2, wherein the heat insulation board layer comprises magnesium oxide (MgO) and silicon dioxide (SiO₂).
The molten metal vessel of claim 1 or 2, wherein the ceramic-based binder comprises at least one selected from the group consisting of silicon (Si), aluminum (Al), titanium (Ti), zirconium (Zr), calcium (Ca), magnesium (Mg), yttrium (Y), and cerium (Ce).
The molten metal vessel of claim 1 or 2, wherein the plurality of hollow particles comprise at least one of silicon dioxide (SiO₂), aluminum oxide (Al₂O₃), and magnesium oxide (MgO) particles having hollow portions.
The molten metal vessel of claim 2, further comprising a plurality of fasteners configured to connect and bind the inner steel shell layer and the outer steel shell layer.
The molten metal vessel of claim 6, wherein the plurality of fasteners comprises a plurality of fastening bolts binding the inner steel shell layer and the outer steel shell layer in a state of penetration through the heat insulation board layer 223, and pressing the inner steel shell layer and the outer steel shell layer against the heat insulation board layer by the binding.