WO2022131821A1

WO2022131821A1 - Mold

Info

Publication number: WO2022131821A1
Application number: PCT/KR2021/019194
Authority: WO
Inventors: 이형준; 김성연; 권상흠; 김지준; 조경철
Original assignee: 주식회사 포스코
Priority date: 2020-12-17
Filing date: 2021-12-16
Publication date: 2022-06-23
Also published as: EP4265352A1; KR20220087174A; KR102441319B1; JP2023546152A; CN116615294A

Abstract

An embodiment of the present invention relates to a mold having an inner space into which molten steel can be injected, the mold including a body having the inner space, wherein the body inner surface facing the inner space includes a first inclined surface that gradually slants toward the lower side thereof to become farther from an outer surface, which is the surface opposite to the inner surface, and a second inclined surface that is provided at the lower side of the first inclined surface and gradually slants toward the lower side thereof to become closer to the outer surface. Therefore, according to embodiments of the present invention, a compensation rate for the shrinkage of a solidified shell is improved. The compensation rate for the shrinkage of the solidified shell in the directions of the long and short sides thereof is improved by means of a convex member and the inclined surfaces provided at the inner surface of the body. Specifically, the compensation rate for the shrinkage of the solidified shell at the upper portion of the inner space of the mold is improved. Thus, a gap can be restrained or prevented from being generated between the inner surface of the mold and the solidified shell by means of the shrinkage of the solidified shell, and solidification delay caused thereby can be restrained or prevented. Therefore, the occurrence of surface defects on a slab and the occurrence of a breakout can be restrained or prevented.

Description

template

The present invention relates to a mold, and more particularly, to a mold capable of suppressing or preventing the occurrence of defects in the cast and damage to the mold.

Cast steel is manufactured by pouring molten steel into a mold having a certain internal shape and solidifying the molten steel in the mold. In this case, a rectangular mold in which the long side part and the short side part are assembled is generally used.

When molten steel is supplied into the mold, a solidified shell begins to form from the molten steel in the mold, and the thickness of the solidified shell becomes thicker as it goes down. And, when the molten steel is solidified inside the mold to form a solidified shell, solidification and shrinkage occur in the solidified shell. In particular, when molten steel in liquid phase is transformed into a solid phase in the upper part of the mold, large shrinkage of the solidified shell occurs. If the mold does not compensate for this shrinkage of the solidification shell, an air layer or gap is created between the mold and the solidification shell. When a gap is created, the heat transfer capability between the mold and the solidified shell or molten steel is reduced, resulting in a delayed solidification phenomenon, thereby causing breakouts and defects in the cast steel.

In order to solve this problem, a slope was given to the mold so that the width decreased toward the bottom. That is, by installing such that the distance between the pair of short sides decreases toward the bottom, the shrinkage of the solidified shell in the long side direction of the mold is compensated, and the separation distance between the pair of long sides decreases toward the bottom. The shrinkage of the solidified shell in the short side direction was compensated. However, even in this case, the shrinkage of the solidified shell cannot be sufficiently compensated, and a gap is still generated between the mold and the solidified shell.

In addition, in order to sufficiently compensate for the coagulation and shrinkage of the upper part of the mold, the installation inclination of the short side of the mold is made larger. However, in this case, wear occurs between the short side of the slab and the short side of the mold at the lower part of the mold, and accordingly, the life of the mold is reduced and the quality of the slab is deteriorated.

(Prior art document) (Patent Document 1) Korean Patent Laid-Open Patent KR 10-2000-008003

The present invention provides a mold capable of compensating for the shrinkage of the solidified shell.

The present invention provides a mold capable of improving the compensation rate for solidified shell shrinkage.

The present invention provides a mold capable of suppressing or preventing abrasion of the mold inner wall by the cast slab.

An embodiment of the present invention is a mold having an inner space into which molten steel can be injected, and includes a body having the inner space, and the inner surface of the body facing the inner space is opposite to the inner surface toward the lower side. It includes a first inclined surface inclined away from the outer surface, which is a surface, and a second inclined surface that is provided below the first inclined surface and inclined toward the lower side toward the outer surface.

The first inclined surface is formed to extend from the upper end ( _PU ) of the inner surface of the body to a first point (P ₁ ) spaced apart by a first distance (S ₁ ), and the second inclined surface is the first point (P ₁ ) ), and is formed extending from the second point (P ₂ ) spaced apart by a second distance (S ₂ ) from the upper end (P _U ) of the inner surface of the body to the lower end (P _L ) of the inner surface of the body, The first distance (S ₁ ) and the second distance (S ₂ ) are shorter than the height (H ₁ ) of the body.

The first distance S ₁ may be 15% or more and 25% or less of the body height H ₁ .

The first inclined surface is a shape in which the inclination slope is changed based on the first inflection point (IP ₁ ) between the upper end (P _U ) of the inner surface of the body and the first point (P ₁ ), and in the first inclined surface , an angle between the lower region and the outer surface of the first inflection point IP ₁ may be smaller than an angle between the upper region and the outer surface of the first inflection point IP ₁ .

The first inflection point (IP ₁ ) is provided in plurality, and the plurality of first inflection points (IP ₁ ) is between the upper end (P _U ) of the inner surface of the body and the first point (P ₁ ). provided in a different location.

The second distance S ₂ may be 40% or more and 50% or less of the body height H ₁ .

The second inclined surface has a shape in which the inclination inclination is changed based on the second inflection point IP ₂ between the second point P ₂ and the lower end P _L of the inner surface of the body, and in the second inclined surface , an angle between the lower region and the outer surface of the second inflection point IP ₂ may be greater than an angle between the upper region and the outer surface of the second inflection point IP ₂ .

The second inflection point (IP ₂ ) is provided in plurality, and the plurality of second inflection points (IP ₂ ) is between the second point (P ₂ ) and the lower end ( _PL ) of the inner surface of the body. It may be provided at another location.

An intermediate surface having the same separation distance from the outer surface in the vertical direction may be provided between the first inclined surface and the second inclined surface.

The body may include a pair of long side members each extending in one direction and installed to face each other in a direction crossing the extending direction; and a pair of short-side members each extending to intersect the long-side member and facing each other to seal between the pair of long-side members, wherein the first and second inclined surfaces are the short-side member and the long-side member. It may be provided on the inner surface of at least one of the members.

The pair of short-side members are installed to be inclined so that the separation distance decreases downward, and the side of the short-side member in contact with the long-side member may be inclined toward the center in the width direction of the short-side member toward the lower side.

The body may include protruding members formed to protrude toward the inner space at both ends in the extending direction of the short-side member so as to form a chamfered surface at the corner of the cast slab.

and a convex member which is formed to protrude from the inner surface of at least one of the long side member and the short side member toward the inner space, and whose protrusion length from the inner surface toward the inner space decreases toward the lower side, wherein the width of the convex member is It may be shorter than the width of the body.

The height of the convex member may be shorter than the height of the body.

The convex member is formed to extend from the upper end ( _PU ) of the inner surface of the body to a third point (P ₃ ) spaced apart by a third distance (S ₃ ), and the third distance (S ₃ ) is the first distance It may be longer than (S ₁ ) and shorter than the second distance (S ₂ ).

The slope at which the protrusion length decreases as the convex member goes downward, the slope is changed based on the third inflection point (IP ₃ ) between the upper end (P _U ) and the third point (P ₃ ) of the body,

In the convex member, an angle between the lower region of the third inflection point IP ₃ and the outer surface may be greater than an angle between the upper region and the outer surface of the third inflection point IP ₃ .

The third inflection point (IP ₃ ) is provided in plurality, and the plurality of third inflection points (IP ₃ ) is between the upper end (P _U ) of the inner surface of the body and the third point (P ₃ ). It may be provided at another location.

According to embodiments of the present invention, the compensation rate for the solidification shell shrinkage is improved. That is, by the inclined surface and the convex member provided on the inner surface of the body, the compensation rate for the contraction in the long and short sides of the solidified shell is improved. In particular, the compensation rate for the shrinkage of the solidified shell in the upper part of the inner space of the mold is improved. Accordingly, it is possible to suppress or prevent the occurrence of a gap between the inner surface of the mold and the solidified shell due to the shrinkage of the solidified shell, thereby suppressing or preventing the delayed solidification phenomenon. Accordingly, it is possible to suppress or prevent the occurrence of defects and breakouts on the surface of the cast steel.

In addition, by the inclined surface provided on the inner surface of the mold, it is possible to reduce the friction between the inner surface of the mold and the cast, thereby extending the life of the mold.

1 is a view showing a casting apparatus including a mold according to embodiments of the present invention.

Figure 2 is a three-dimensional view showing a mold according to the first embodiment of the present invention, Figure 3 is an exploded perspective view of the mold.

4 is a front view viewed from the 'A' side of FIG. 2 in order to explain the installation state of the pair of short sides.

FIG. 5 is a cross-sectional view viewed from the side 'A' by cutting the short side of FIG. 2 along line B-B'.

6 is a front view of the short side of FIG. 2 viewed from the 'C' side.

7 is a view for explaining the solidification shell formed on the upper portion (FIG. 7 (a)) and the solidification shell formed on the lower side (FIG. 7 (b)) in the mold according to the first embodiment of the present invention.

Figure 8 (a) is a three-dimensional view of the short side portion according to the first embodiment of the present invention.

Fig. 8 (b) is a front view of Fig. 8 (a) viewed from the 'D' side.

(c) of FIG. 8 is a cross-sectional view taken along line E-E' of FIG. 8(a) and viewed from the side 'F'.

8 (d) is a top view at each position ⓐ, ⓑ, ⓒ in the vertical direction (Z-axis direction) of FIG. 8 (c).

9 is a view for explaining the extension length of the inner surface of the short side in the short side according to the first embodiment of the present invention.

10 and 11 are views showing the short sides of the molds according to the first and second modifications of the first embodiment.

12 is a view showing a short side portion of a mold according to a third modification of the first embodiment.

13 to 15 are views showing the short sides of the molds according to the fourth to sixth modifications of the first embodiment.

16 is a three-dimensional view showing a mold according to a second embodiment of the present invention, and FIG. 17 is an exploded perspective view.

18 is a three-dimensional view showing a mold according to a third embodiment of the present invention.

19 is a three-dimensional view showing the short side of the mold according to the third embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art completely It is provided to inform you. The drawings may be exaggerated in order to explain the embodiment of the present invention, and like reference numerals in the drawings refer to the same components.

1, the casting apparatus is a tundish 20 for receiving and storing molten steel from the ladle 10, a mold for receiving molten steel from the tundish 20 and initially solidifying it into a predetermined shape (mold) (3000), It includes a nozzle 22 for supplying the molten steel of the tundish 20 to the mold (3000).

In addition, the casting apparatus is installed on the lower side of the mold 3000, and includes a cooling unit 40 for completely solidifying by spraying cooling water to the unsolidified cast 1 drawn from the mold (3000). Here, the cooling unit 40 includes a plurality of segments 41 . And, each of the plurality of segments 41 may be a means having a plurality of rolls rotatable by the force of the movement of the cast slab 1 and a nozzle positioned between the plurality of rolls to spray the coolant to the slab 1 . .

Hereinafter, a mold according to the first embodiment of the present invention will be described with reference to FIGS. 2 to 7 .

Figure 2 is a three-dimensional view showing a mold according to the first embodiment of the present invention, Figure 3 is an exploded perspective view of the mold. 4 is a front view viewed from the 'A' side of FIG. 2 in order to explain the installation state of the pair of short sides. FIG. 5 is a cross-sectional view viewed from the side 'A' by cutting the short side of FIG. 2 along line B-B'. 6 is a front view of the short side of FIG. 2 viewed from the 'C' side. 7 is a view for explaining the solidification shell formed on the upper portion (FIG. 7 (a)) and the solidification shell formed on the lower side (FIG. 7 (b)) in the mold according to the first embodiment of the present invention.

Here, FIG. 5 illustrates a state in which the short side is vertically erected with respect to the ground for a detailed description of the inner surface of the short side.

2 and 3, the mold 3000 has an inner space (IS), the inner space (IS) toward the inner surface (if) toward the lower side toward the outer surface (of) inclined away from the first It includes a body 3100 provided with an inclined surface sf ₁ and a second inclined surface sf ₂ provided below the first inclined surface sf ₁ and inclined toward the lower side toward the outer surface of.

In addition, the mold 3000 is formed to protrude from the inner surface (if) of the body 3100 toward the inner space (IS), toward the lower side from the inner surface (if) of the body 3100 toward the inner space (IS). and a convex member 3122 provided to decrease the protrusion length PL (see FIG. 5 ).

As shown in FIGS. 2 and 3, the body 3100 is formed to extend in one direction (X-axis direction), and a pair of long-side members (Y-axis direction) are spaced apart from each other Hereinafter, the first and second long-side members 3111) and each are formed to extend in a direction (Y-axis direction) intersecting or orthogonal to the extending direction (X-axis direction) of the long-side member 3111, and the long side member 3111 It includes a pair of short side members 3121 (hereinafter, first and second short side members 3121) spaced apart installed in the extending direction of the.

A convex member 3122 is installed on the inner surface (if) of the body 3100, and the convex member 3122 may be installed on the inner surface of the short side member 3121 as shown in FIGS. 2 and 3 . . Hereinafter, a configuration including the short side member 3121 and the convex member 3122 installed on the short side member 3121 is defined as the short side portion 3120 . In this case, the mold 3000 may be described as including the first and second long side members 3111 and the first and second short side portions 3120 including the convex member 3122 .

As described above, the first and second long side members 3111 and the first and second short side members 3121 are interconnected or combined to provide a body 3100 having an internal space IS. For example, one end of each of the first and second short side members 3121 in the Y-axis direction is connected to the inner surface of the first long side member 3111 , and the other end is connected to the inner surface of the second long side member 3111 . do. In addition, the first short side member 3121 and the second short side member 3121 are arranged in the X-axis direction to be spaced apart. In this case, the separation distance between the first short side member 3121 and the second short side member 3121 is disposed to be greater than the separation distance between the first long side member 3111 and the second long side member 3111 . Accordingly, the body 3100 having a rectangular shape of the inner space IS is provided. More specifically, the body 3100 having a rectangular inner space IS having a length in the X-axis direction longer than the length in the Y-axis direction is provided.

Hereinafter, the extending direction of each of the long side member 3111 and the short side member 3121 is defined as a width direction. Accordingly, the length in the extending direction of each of the long side member 3111 and the short side member 3121 may be defined as a 'width'. Accordingly, the width of the long side member 3111 is the length in the X-axis direction, and the width of the short side member 3121 is the length in the Y-axis direction. In addition, in each of the long-side member 3111 and the short-side member 3121 in the horizontal direction, a length in a direction crossing the width direction is defined as 'thickness'. Accordingly, the thickness of the long side member 3111 is the length in the Y-axis direction, and the thickness of the short side member 3121 is the length in the X-axis direction.

In installing the first short side member 3121 and the second short side member 3121 to face each other, as shown in FIGS. 2 and 4, the first and The second short side member 3121 is installed at an angle. More specifically, among the inner surfaces (if) of the first and second short side members 3121 , the first and second short side members such that the separation distance SL between at least the second inclined surface sf ₂ decreases toward the lower side. (3121) is installed at an angle. Accordingly, the length of the long side in the inner space IS of the mold 3000 decreases toward the lower side. In this way, the separation distance SL between the first and second short side members 3121 is installed to decrease toward the lower side to compensate for the contraction in the long side direction of the solidified shell (C). More specifically, a solidification shell (hereinafter, a long-side solidification shell (LC)) formed by solidifying the molten steel M along the first and second long-side members 3111 (see FIG. 7 ) is the first and second long-side members In the contraction in the extension direction of 3111, this is to compensate for the contraction.

In addition, as shown in FIG. 6 , each of the first and second short side members 3121 is provided such that the extended length, that is, the width SW, decreases toward the lower side thereof. In other words, each of the first and second short side members 3121 is provided to decrease the extension length SW in the Y-axis direction, which is the short side direction of the mold 3000 , respectively, toward the lower side. Accordingly, both sides corresponding to one end and the other end of the first and second short side members 3121 are provided to be inclined with respect to the Y-axis direction. That is, the side surfaces of the first and second short side members 3121 are inclined to be closer to the center in the width direction toward the lower side. In addition, the first and second long side members 3111 are connected to the respective side surfaces of the first and second short side members 3121 . Accordingly, the first and second long side members 3111 are installed such that the separation distance decreases toward the lower side.

In this way, the side of the short side member 3121 is formed to be inclined, and the pair of long side members 3111 installed in contact with the short side member 3121 are installed so as to be closer to each other toward the lower side, the solidification shell (C) This is to compensate for the unilateral contraction of That is, the solidification shell formed by solidifying the molten steel M formed along the first and second short-side members 3121 (hereinafter, the short-side solidification shell (SC)) (see FIG. 7) is the first and second short-side members ( 3121), in order to compensate for the contraction in the extension direction.

Hereinafter, in the mold according to the first embodiment of the present invention, the inner surface of the body will be described with reference to FIGS. 3 to 6 .

The inner surface of the body 3100 is provided to include the first and second inclined surfaces sf ₁ and sf ₂ as described above. At this time, among the long side member 3111 and the short side member 3121 constituting the body 3100 , as shown in FIGS. 3 to 6 , the inner surface (if) of the short side member 3121 has the first and second inclined surfaces sf. ₁ , sf ₂ ) may be provided to include. At this time, since the first and second short side members 3121 have the same shape, they will be collectively referred to as the short side members 3121 .

As described above, the body 3100 includes a long side member 3111 and a short side member 3121 . Accordingly, the inner surface (if) of the body 3100 means inner surfaces of the long side member 3111 and the short side member 3121 . Accordingly, the inner surface (if) of the body 3100 and the inner surface (if) of the long side member and the short side member will be described with the same reference numeral 'if'. In addition, the outer surface of the body and the outer surface of the long side member and the short side member will be described with the same reference numeral 'of'. In addition, since the body 3100 is a configuration of the mold 3000 , the inner and outer surfaces of the short side member 3121 and the long side member 3111 may refer to the inner and outer surfaces of the mold 3000 .

The short side member 3121 is provided so that the inner surface (if) facing the inner space of the mold (3000) includes an inclined surface. That is, the inner surface (if) of the mold (3000) includes an inclined surface, and the inclined surface is a first inclined surface (sf ₁ ) inclined away from the outer surface (of) toward the lower side as shown in FIGS. 4 and 5 . and a second inclined surface sf ₂ provided below the first inclined surface sf ₁ and inclined toward the lower side toward the outer surface of. In addition, the inner surface if may include an intermediate surface cf, which is a surface positioned between the first inclined surface sf ₁ and the second inclined surface sf ₂ . That is, the inner surface (if) of the short side member 3121 includes a first inclined surface (sf ₁ ), a middle surface (cf), and a second inclined surface (sf ₂ ), the first inclined surface (sf ₁ ), the intermediate surface ( cf), the second inclined surface (sf ₂ ) is formed to be continuously arranged in the order.

And, referring to FIGS. 4 and 5 , the first inclined surface sf ₁ , the intermediate surface cf, and the second inclined surface sf ₂ are provided to have different inclinations. This may be described as having an inner surface (if) of the short side member 3121 has a multi-stage inclination, more specifically, it may be described as having a three-stage inclination.

Among the inner surfaces (if) of the short side member 3121 , the connection point of the first inclined surface sf ₁ and the intermediate surface cf is a point at which the inclination starts to change, and the intermediate surface cf and the second inclined surface sf The connecting point of ₂ ) is the point where the slope starts to change. Therefore, hereinafter, for convenience of explanation, a point between the first inclined surface sf ₁ and the intermediate surface cf is defined as the first point P ₁ , and between the intermediate surface cf and the second inclined surface sf ₂ . The point is called a second point (P ₂ ). And, the length from the upper end (P _U ) to the lower end ( _PL ) of the short side member 3121 is called the height (H ₁ ) of the short side member 3121 .

The first inclined surface sf ₁ is an inclined surface formed on the inner surface if of the body 3100, and is formed to extend downward by a predetermined length from the _uppermost end PU of the inner surface if of the short side member 3121. do. At this time, as described above, the first inclined surface sf ₁ is inclined or inclined so as to be further away from the outer surface of toward the lower side. In other words, the first inclined surface sf ₁ is inclined toward the lower side to be closer to the center of the inner space IS of the mold 3000 . Accordingly, a portion of the short side member 3121 in which the first inclined surface sf ₁ is provided may have a shape in which the thickness becomes thicker toward the lower side.

Referring to FIG. 5 , the first inclined surface sf ₁ is formed to extend from the upper end PU of the short side member ₃₁₂₁ to the first point P ₁ . In this case, the first inclined surface sf ₁ may be provided to have a constant inclination from the upper end PU of the short side member ₃₁₂₁ to the first point P ₁ . That is, it may be provided with a constant slope without a change in slope or an inflection point.

The first point P ₁ may be described as a point separated by a first distance S ₁ downward from the upper end PU of the short side member ₃₁₂₁ . Accordingly, the first inclined surface sf ₁ may be described as extending from the upper end PU of the short side member ₃₁₂₁ downward to the first point P ₁ spaced apart by a first distance S ₁ . . The first distance (S ₁ ) may be 15% or more and 25% or less of the height of the short side member (H ₁ ). Accordingly, the first point (P ₁ ) is a point that is spaced apart by a length of 15% or more and 25% or less of the height (H ₁ ) of the short side member 3121 downward from the upper end (P _U ) of the short side member. can Accordingly, the first inclined surface (sf ₁ ) is a distance (S ₁ ) between the upper end (P _U ) and the first point (P ₁ ) of the short side member 3121 is 15% of the short side member 3121 height (H ₁ ) More than or equal to 25% or less is formed to extend.

The second inclined surface sf ₂ is an inclined surface formed under the inner surface if of the body 3100, and is provided below the first inclined surface sf ₁ . At this time, as described above, the second inclined surface sf ₂ is provided to be inclined toward the lower side to be closer to the outer surface of. Accordingly, a portion of the short side member 3121 provided with the second inclined surface sf ₂ may have a shape in which the thickness becomes thinner toward the lower side.

As shown in FIG. 5 , the second inclined surface sf ₂ extends from the second point P ₂ , which is a lower position of the first point P ₁ , to the lower end P _L of the short side member 3121 ). do. In this case, the second inclined surface sf ₂ may be provided to have a constant inclination from the second point P ₂ to the lower end P _L of the short side member 3121 . That is, it may be provided with a constant slope without a change in slope or an inflection point.

The second point (P ₂ ) is a point separated by a second distance (S ₂ ) that is longer than the first distance ( S ₁ ) downward from the upper end ( _PU ) of the short side member 3121 . Accordingly, the second inclined surface sf ₂ is a second point P ₂ spaced apart from the upper end P _U of the short side member 3121 by a second distance S ₂ downward from the short side member 3121 at the lower end ( It can be described as extending to P _L ). The second distance S ₂ may be greater than 40% and less than or equal to 50% of the height H ₁ of the short side member 3121 . Accordingly, the second inclined surface sf ₂ is, from the upper end PU of the short side member ₃₁₂₁ to the lower side, the height H ₁ of the short side member 3121 is greater than 40% and less than or equal to 50% of the second distance S ₂ ) is formed extending from the second point (P ₂ ) spaced apart to the lower end ( _PL ) of the short side member (3121).

The intermediate surface cf is a surface provided between the first inclined surface sf ₁ and the second inclined surface sf ₂ , and is a surface provided to have the same separation distance from the outer surface of in the vertical direction. Accordingly, a portion of the short side member 3121 provided with the intermediate surface cf may have a constant or constant thickness in the vertical direction.

The middle surface cf is formed extending from the first point P ₁ to the second point P ₂ . In other words, the middle surface (cf) is a second distance from a point (a first point (P ₁ )) spaced apart by a first distance (S ₁ ) downward from the upper end (P _U ) of the short side member 3121 ( S ₂ ) is formed extending to a spaced apart point (the second point (P ₂ )). The intermediate surface cf may not be inclined when the short side member 3121 is disposed in a state perpendicular to the ground as shown in FIG. 5 , that is, it may be provided to be perpendicular to the ground.

As described above, the first inclined surface sf ₁ , which is the upper inner surface of the short side member 3121 , is formed to be inclined toward the lower side and away from the outer surface of. This is to further compensate for the longitudinal contraction of the solidification shell (C) in the upper part of the mold (3000) in which the solidification contraction occurs relatively large. That is, in installing the first and second short side members 3121 to face each other, as described above, as described above, it is possible to compensate for coagulation shrinkage in the long side direction by installing inclined so that the distance between each other is closer to the lower side as described above. Here, by providing a first inclined surface (sf ₁ ) on the inner surface (if) of the short side member 3121, it is possible to further compensate for the coagulation contraction in the long side direction. This is, in the rate of decrease in which the length of the long side of the inner space IS of the mold 3000 decreases toward the lower side, the decrease rate caused by installing the short side member 3121 to be inclined is the decrease rate due to the first inclined surface sf ₁ ) Because this adds more.

Accordingly, when the first inclined surface sf 1 is provided on the short side member 3121 , compared to the case where the first inclined surface sf ₁ is not provided, the long side (X-axis direction) length of the inner space of the mold 3000 decreases toward the lower side. . Therefore, when the first inclined surface sf ₁ is provided on the short side member 3121, the coagulation and shrinkage compensation rate in the long side direction of the mold 3000 is improved compared to the case where it is not. In particular, the compensation rate in the upper part of the mold 3000 in which the coagulation and shrinkage occurs is improved. For this reason, it is possible to suppress or prevent the occurrence of a gap between the long-side solidified shell LC (see FIG. 7 ) and the short-side member 3121, and suppress the occurrence of surface cracks and breakouts due to the contraction of the solidified shell LC. or it can be prevented.

In addition, the second inclined surface sf ₂ is inclined toward the lower side to be closer to the outer surface of. This is to suppress friction between the inner surface of the slab 1 and the short side member 3121 formed by solidifying molten steel in the lower part of the mold 3000 . That is, in order to compensate for the coagulation and contraction in the long side direction, the first and second short side members 3121 are installed to be inclined so that the separation distance between them becomes closer toward the lower side. Accordingly, in the lower part of the mold 3000, the separation distance between the first short side member 3121 and the second short side member 3121 is greatly reduced. Friction may occur between the cast steel 1 and the short side member 3121 . However, by forming the second inclined surface sf ₂ on the short side member 3121, it is possible to suppress or prevent friction between the cast steel 1 and the short side member 3121.

This is, as shown in FIGS. 4 and 5, when the second inclined surface sf ₂ is provided to be closer to the outer surface as it goes downward, and not when it is provided as a vertical surface, compared to the case where it is provided as a vertical surface. ) is because the separation distance from the center can be increased, and thus, the adhesion between the cast slab 1 and the short side member 3121 can be reduced. And, as the frictional force between the cast slab 1 and the short side member 3121 is reduced, it is possible to reduce the wear of the short side member 3121, thereby extending the life of the short side member 3121, that is, the mold 3000. .

On the other hand, in the inner space (IS) of the mold (3000), the shrinkage amount of the solidified shell at the top is the largest, and the shrinkage amount decreases toward the lower side. And, the position where the intermediate surface cf is provided is the central portion of the mold 3000, and the amount of shrinkage is small compared to the upper part, but the amount of shrinkage is large compared to the lower part. Accordingly, it is necessary to compensate for the amount of shrinkage in the central portion.

However, when the second inclined surface sf ₂ is continuously formed from the first point P ₁ without the intermediate surface cf, in the central part of the inner space of the mold 3000, the length in the long side direction decreases toward the lower side. The decreasing rate of decrease may be small. Accordingly, the coagulation and contraction in the central portion of the inner space IS of the mold 3000 may not be sufficiently compensated.

In addition, when the first inclined surface (sf ₁ ) is formed to extend to the two points (P ₂ ), the problem of excessive compensation compared to the amount of contraction of the solidified shell in the central part of the inner space (IS) of the mold (3000) occurs. can be

Therefore, it is preferable to provide an intermediate surface cf with no change in the separation distance from the outer surface of in the vertical direction between the first inclined surface sf ₁ and the second inclined surface sf ₂ or the inclination change between the first and second inclined surfaces sf 2 . do.

The convex member 3122 is installed on the inner surface (if) of the body (3100). That is, the convex member 3122 is installed to protrude from the inner surface (if) of the body 3100 toward the inner space (IS). In this case, the convex member 3122 may be installed on the inner surface (if) of the short side member 3121 as shown in FIGS. 2, 3 and 6 .

Hereinafter, the short side part including the short side member and the convex member will be described with reference to FIGS. 2, 3, 8 and 9 .

Figure 8 (a) is a three-dimensional view of the short side portion according to the first embodiment of the present invention. Fig. 8 (b) is a front view of Fig. 8 (a) viewed from the 'D' side. (c) of FIG. 8 is a cross-sectional view taken along line E-E' of FIG. 8(a) and viewed from the side 'F'. 8 (d) is a top view at each position ⓐ, ⓑ, ⓒ in the vertical direction (Z-axis direction) of FIG. 8 (c).

* Referring to FIGS. 2, 3 and 8 (a), the convex member 3122 is installed on the inner surface (if) of the short side member 3121 . That is, the convex member 3122 is installed to protrude from the inner surface (if) of the short side member (3121) toward the inner space (IS) of the mold (3000).

The convex member 3122 is formed to extend in the extension direction of the short side member 3121 , that is, in the width direction (Y-axis direction). At this time, the convex member 3122 has a shape in which the protrusion length PL increases from both ends in the extending direction toward the center. In other words, the convex member 3122 may have a shape in which the protrusion length PL decreases from the center in the width direction toward both ends. Accordingly, in the width direction of the convex member 3122 , the position having the maximum protrusion length PL may be the center of the convex member 3122 in the width direction. At this time, it is preferable that the center of the convex member 3122 in the width direction coincides with the center of the short side member 3121 in the width direction.

In addition, the convex member 3122 may be provided in a shape in which the protrusion length PL in the width direction is constant or the same.

The width PW of the convex member 3122 is provided to be smaller than the width SW of the short side member 3121 as shown in FIGS. 8A and 8B . Accordingly, as shown in (b) of FIG. 8 , the inner surface if of the short side member 3121 is exposed on the outer side in the width direction of the convex member 3122 . And, the convex member 3122 is provided such that the width PW is constant in the vertical direction as shown in FIGS. 8 (b) and (d). Accordingly, as shown in (b) of FIG. 8 , a line connecting the uppermost end and the lowermost end of the convex member 3122 (hereinafter, the boundary line DL) may be a straight line having no curvature.

The convex member ₃₁₂₂ is formed to extend downward from the upper end PU of the inner surface if the short side member 3121, and at this time, as shown in FIGS. The protrusion length PL is formed to decrease. That is, the protrusion length PL of the lower part of the convex member 3122 is shorter than that of the upper part. In addition, the convex member 3122 may be provided with a constant decreasing slope in which the protrusion length PL of the convex member 3122 decreases downward as shown in FIG. 8C .

The vertical extension length of the convex member 3122 is shorter than the height H ₁ of the short side member 3121 . That is, the convex member 3122 is formed to extend downward from the upper end PU of the short side member ₃₁₂₁ to a point (hereinafter, the third point P ₃ ). At this time, the distance (hereinafter, the third distance (S ₃ )) between the upper end (P _U ) and the third point (P ₃ ) of the short side member 3121 is greater than the first distance (S ₁ ), and the second It is short compared to the distance (S ₂ ). More specifically, the third distance S ₃ may be 30% or more and 40% or less of the height H ₁ of the short side member 3121 . Accordingly, the third point (P ₃ ) is a point spaced apart by a length of 30% or more and 40% or less of the height (H ₁ ) of the short side member 3121 downward from the upper end (P _U ) of the short side member 3121. can be explained as That is, the distance S ₃ between the upper end PU of the short side member ₃₁₂₁ and the third point P ₃ is 30% or more and 40% or less of the height H ₁ of the short side member 3121. The member 3122 is formed to extend.

As such, as the convex member 3122 is formed on the inner surface (if) of the short side member 3121 to protrude or convex toward the inner space of the mold 3000, the extension length of the inner surface of the short side member 3120 is conventionally lengthened compared to Here, the inner surface of the short side portion 3120 is the other side opposite to one side of the convex member 3122 connected to the short side member 3121 and the short side member 3121 located outside the convex member 3122 in the width direction. ) refers to the surface including the inner surface (if). In addition, the extension length (SIL) of the inner surface (if) of the short side part 3120 is one end (SIL) which is one of both ends in the Y-axis direction of the inner surface of the short side part 3120 as shown in FIG. E ₁ ) refers to the length of the path from the other end (E ₂ ).

The inner surface of the short side portion 3120 is not a straight line but a curved shape bent at least once by the convex member 3122 . And, compared to the path from one end of the straight line to the other end (refer to (b) of FIG. 9), the length of the path from one end of the curve to the other end (refer to (a) of FIG. 9) is longer. Accordingly, as for the extension length SIL of the inner surface of the short side 3120, the longer the protrusion length PL of the convex member 3122, the longer the path from one end E ₁ to the other end E ₂ of the inner surface increases. The extended length SIL of the inner surface of the short side 3120 is increased. And, the protrusion length PL of the convex member 3122 decreases toward the lower side. Accordingly, the extended length of the inner surface of the short side portion 3120 decreases toward the lower side.

On the other hand, the short side member 3121 is provided to decrease in width toward the lower side. Accordingly, the length in the short side direction of the inner space of the mold 3000 decreases toward the lower side. At this time, compared to the case where the convex member 3122 is not provided in the short side member 3121 , the reduction rate in which the length of the short side direction of the inner space IS of the mold 3000 decreases toward the lower side is large. This is, in the decrease rate in which the length of the short side direction of the inner space (IS) of the mold (3000) decreases toward the lower side, the reduction rate generated by reducing the width of the short side member 3121, the protrusion length (PL) toward the lower side This is because the reduction rate due to the convex member 3122 provided to decrease is further added.

Accordingly, the mold 3000 may further compensate for the coagulation and contraction in the short side direction through the convex member 3122 . That is, by installing the convex member 3122 on the short side member 3121, it is possible to further compensate for the coagulation contraction in the short side direction. Accordingly, the coagulation shrinkage compensation rate in the short side direction of the mold 3000 is improved. For this reason, it is possible to suppress or prevent the occurrence of a gap between the short-side solidified shell SC and the long-side member 3111, and suppress or prevent the occurrence of surface cracks and breakouts due to the contraction of the solidified shell.

10 and 11 are views showing the short sides of the molds according to the first and second modifications of the first embodiment. 12 is a view showing a short side portion of a mold according to a third modification of the first embodiment.

In the above-described first embodiment, it has been described that the first inclined surface sf ₁ is formed to have a constant inclination up to the first point P ₁ , that is, a constant inclination. However, the present invention is not limited thereto, and as in the first modified example shown in FIG. 10 , the first inclined surface sf ₁ may be provided to have a multi-stage inclination. That is, the first inclined surface sf ₁ may be formed to be inclined so as to be farther away from the outer surface of toward the lower side, and the inclination may be changed at least once or more. In other words, the first inclined surface sf ₁ is inclined with respect to a point (the first inflection point IP ₁ ) between the upper end PU of the short side member ₃₁₂₁ and the first point P ₁ ). can be arranged to change. At this time, based on the first inflection point (IP ₁ ), the slope of the lower region is provided to be smaller than that of the upper region. In this way, when one first inflection point IP ₁ is provided between the upper end PU of the short side member ₃₁₂₁ and the first point P ₁ , the first inclined surface sf ₁ is a two-stage It can be described as being provided to have an inclination. The first inclined surface sf ₁ is not limited to being provided to have an inclination of two stages, and may be provided to have an inclination of three or more stages. To this end, the first inflection point (IP ₁ ) may be provided in two or more.

In addition, in the above-described first embodiment, it has been described that the second inclined surface sf ₂ is formed to have a constant inclination or a constant inclination from the second point P ₂ to the lower end of the short side member 3121 . However, the present invention is not limited thereto, and as in the second modified example shown in FIG. 11 , the second inclined surface sf ₂ may be provided to have a multi-stage inclination. That is, the second inclined surface sf ₂ is inclined to be closer to the outer surface of toward the lower side, and the second inclined surface sf 2 may be formed to change the inclination at least once or more. In other words, the second inclined surface sf ₂ is inclined with respect to a point (the second inflection point IP ₂ ) between the second point P ₂ and the lower end P _L of the short side member 3121 ). is changing At this time, the second inflection point (IP ₂ ) is provided so that the slope of the lower region is greater than that of the upper region as a reference. As such, when one second inflection point IP ₂ is provided between the second point P ₂ and the lower end P _L of the short side member 3121, the second slope sf ₂ is a slope of two stages. will have The second inclined surface sf ₂ is not limited to being provided to have an inclination of two stages, and may be provided to have an inclination of three or more stages. To this end, the second inflection point (IP ₂ ) may be provided in two or more.

In addition, in the above-described first embodiment, it has been described that the protrusion length PL of the convex member 3122 from the upper end PU of the short side member ₃₁₂₁ to the third point P ₃ decreases at a constant rate. That is, the convex member 3122 according to the first embodiment is provided to have a constant inclination from the upper end PU of the short side member ₃₁₂₁ to the third point P ₃ .

However, the present invention is not limited thereto, and as in the third modified example shown in FIG. 12 , the convex member 3122 may be provided to have a multi-stage inclination. That is, the convex member 3122 may be formed such that the protrusion length PL decreases toward the lower side, and the degree of decrease is changed at least once or more. In other words, when the convex member 3122 extends from the upper end of the short side member 3121 to the third point P ₃ , the inclination thereof may be changed at least once. That is, the convex member 3122 is formed such that the inclination is changed based on a point (the third inflection point IP ₃ ) between the upper end _PU and the third point P ₃ of the short side member 3121 . And, the third inflection point (IP ₃ ) is provided so that the slope of the lower region is greater than that of the upper region as a reference.

The third inflection point IP ₃ may be the same as, for example, the first point P ₁ as shown in FIG. 12 . Of course, the third inflection point (IP ₃ ) may be any position between the upper end (PU) of the short side member ( ₃₁₂₁ ) and the third point (P ₃ ).

In this way, when one third inflection point (IP ₃ ) is provided between the third point (P ₃ ) and the lower end ( _PL ) of the short side member 3121, the convex member 3122 is formed of two steps in the vertical direction. have a slope Of course, the convex member 3122 is not limited to being provided to have an inclination of two stages, and may be provided to have an inclination of three or more stages. To this end, the third inflection point (IP ₃ ) may be provided in two or more.

13 to 15 are views showing the short sides of the molds according to the fourth to sixth modifications of the first embodiment. Here, each of FIGS. 13 to 15 (a) to (d) is a diagram illustrating the same method as the method described in (a) to (d) of FIG. 8 .

In the first embodiment and the first to third modifications described above, the width PW of the convex member 3122 was the same without changing in the vertical direction. However, the present invention is not limited thereto, and as in the fourth to sixth modified examples shown in FIGS. 13 to 15 , the width PW of the convex member 3122 decreases toward the lower side. That is, the convex member 3122 may have a shape in which the protrusion length PL decreases toward the lower side, and at the same time, the width PW also decreases toward the lower side.

As described above, when the width PW of the convex member 3122 decreases toward the lower side, the decrease rate may be constant as shown in FIG. 13 . Accordingly, as shown in FIG. 13 , the line connecting the uppermost end and the lowermost end of the convex member, that is, the boundary line DL) may be a straight line having no curvature.

However, the present invention is not limited thereto, and as in the fifth and sixth modified examples shown in FIGS. 14 and 15 , the boundary line DL may be provided to have a curvature. In this case, as in the fifth modified example of FIG. 14 , the boundary line DL may be convex to the outside of the convex member 3122 or have a positive curvature. Also, as in the sixth modified example shown in FIG. 15 , the convex member may have a shape in which the boundary line DL is concave inward of the convex member 3122 or has a negative curvature. As such, when the boundary line DL is provided to have a positive or negative curvature, it means that the reduction rate is not constant when the width PW of the convex member 3122 decreases toward the lower side.

In the first embodiment described above, the inner surface (if) of the short side member 3121 is the first and second inclined surfaces (sf ₁ ,sf ₂ ), including the intermediate surface (cf), has been described that the convex member (3122) is installed on the short side member (3121). However, the present invention is not limited thereto, and not only the short side member 3121 but also the first and second inclined surfaces sf ₁ of the inner surface if of the long side member 3111 as in the second embodiment shown in FIGS. 16 and 17 . ,sf ₂ ) and the intermediate surface cf, and a convex member 3112 may be installed on the long side member 3111 . In this case, a configuration including the long side member 3111 and the convex member 3112 installed on the long side member 3111 may be defined as the long side portion 3110 . In this case, the mold 3000 is described as including first and second long side portions 3110 including the convex member 3112 and first and second short side portions 3120 including the convex member 3122 . can be..

And, the first and second inclined surfaces sf ₁ of the long side member 3111,For sf ₂ ), the first embodiment and the first and second modifications may be applied. In addition, the first embodiment and the third to sixth modifications may be applied to the convex member 3112 installed on the long side member 3111 .

18 is a three-dimensional view showing a mold according to a third embodiment of the present invention. 19 is a three-dimensional view showing the short side of the mold according to the third embodiment of the present invention.

Hereinafter, a mold according to a third embodiment of the present invention will be described with reference to FIGS. 18 and 19 . In this case, content overlapping with the above-described embodiments will be omitted or briefly described.

The mold 3000 according to the third embodiment may be a chamfered chamfered mold (CHAMFERED MOLD). That is, the mold 3000 has first and second inclined surfaces sf ₁ on the inner surface ifsf ₂ ), a middle surface (cf) is provided, the body 3100 having a protruding member 3123 at the corner, and the body 3100 are formed to protrude from the inner surface (if) of the body 3100 toward the inner space (IS), the lower side It includes a convex member 3122 provided so that the protruding length from the inner surface (if) of the body 3100 toward the inner space decreases toward the direction.

At this time, the first and second inclined surfaces sf ₁ ,sf ₂ ) and the middle surface cf may be provided on the inner surface if of the short side member 3121 . In addition, a convex member 3122 may be installed on the inner surface (if) of the short side member 3121 . Here, the first and second inclined surfaces sf ₁ ,sf ₂ ) can be applied to the first embodiment, the first and second modifications, and the convex member 3122 can be applied to the first embodiment and the third to sixth modifications.

The protruding member 3123 is formed to protrude from the inner surface (if) of the body 3100 toward the inner space, and may be installed to protrude from the inner surface (if) of the short side member 3121 as shown in FIGS. 18 and 19 . . In this case, the protruding member 3123 is provided to be positioned at both edges in the extending direction of the short side member 3121 . That is, it is provided to protrude from the inner surface (if) of both edges of the short side member (3121) toward the inner space (IS) of the mold (3000) in the Y-axis direction. The protruding member 3123 is a configuration for making a shape to be chamfered in the mold 3000 , and may be referred to as a chamfering protruding member 3123 .

In such a chamfered mold (CHAMFERED MOLD), the convex member 3112 may be additionally provided in the long side portion 3110 .

In the above-described embodiments, it has been described that the mold 3000 is composed of a long side member 3111 and a short side member having different lengths, and has a substantially rectangular shape. However, the present invention is not limited thereto, and the mold 3000 may be provided in a square shape.

According to the mold 3000 according to the embodiments of the present invention, the compensation rate for the shrinkage of the solidified shell (C) is improved. That is, by the inclined surface and the convex member provided on the inner surface (if) of the body 3100, the compensation rate for the contraction in the long side direction and the short side direction of the solidified shell is improved together. In particular, the compensation rate for the shrinkage of the solidified shell in the upper portion of the mold (3000) inner space (IS) is improved. Accordingly, it is possible to suppress or prevent the occurrence of a gap (gap) between the inner surface of the mold 3000 and the solidified shell due to the shrinkage of the solidified shell, thereby suppressing or preventing the solidification delay phenomenon. Therefore, it is possible to suppress or prevent the occurrence of defects and breakouts on the surface of the cast steel.

In addition, it is possible to reduce friction between the inner surface (if) of the mold (3000) and the cast steel by the inclined surface provided on the inner surface (if) of the mold (3000), and thus the life of the mold (3000) can be extended .

Claims

As a mold having an inner space into which molten steel can be injected,

including a body having the inner space,

The inner surface of the body facing the inner space is provided on the lower side of the first inclined surface and the first inclined surface inclined away from the outer surface, which is the opposite surface of the inner surface, toward the lower side, and is closer to the outer surface toward the lower side. A mold comprising a second inclined surface that is inclined downward.
The method according to claim 1,

The first inclined surface is formed to extend from the upper end (P U ) of the inner surface of the body to a first point (P 1 ) spaced apart by a first distance (S 1 ),

The second inclined surface is a point below the first point (P 1 ), and from a second point (P 2 ) spaced apart by a second distance (S 2 ) from the upper end (P U ) of the inner surface of the body (P 2 ) in the body It is formed extending to the lower end of the side (P L ),

The first distance (S 1 ) and the second distance (S 2 ) are shorter than the height (H 1 ) of the body.
3. The method according to claim 2,

The first distance (S 1 ) is 15% or more and 25% or less of the body height (H 1 ).
3. The method according to claim 2,

The first inclined surface is a shape in which the inclination inclination is changed based on the first inflection point (IP 1 ) between the upper end (P U ) of the inner surface of the body and the first point (P 1 ),

In the first inclined surface, the angle between the lower area and the outer surface of the first inflection point (IP 1 ) is smaller than the angle between the upper area and the outer surface of the first inflection point (IP 1 ).
5. The method according to claim 4,

The first inflection point (IP 1 ) is provided in plurality, and the plurality of first inflection points (IP 1 ) is between the upper end (P U ) of the inner surface of the body and the first point (P 1 ). Molds prepared in different locations.
3. The method according to claim 2,

The second distance (S 2 ) is 40% or more and 50% or less of the body height (H 1 ).
7. The method of claim 6,

The second inclined surface is a shape in which the inclination inclination is changed based on the second inflection point (IP 2 ) between the second point (P 2 ) and the lower end (P L ) of the inner surface of the body,

In the second inclined surface, the angle between the lower region and the outer surface of the second inflection point (IP 2 ) is larger than the angle between the upper region and the outer surface of the second inflection point (IP 2 ).
8. The method of claim 7,

The second inflection point (IP 2 ) is provided in plurality, and the plurality of second inflection points (IP 2 ) is between the second point (P 2 ) and the lower end ( PL ) of the inner surface of the body. Molds prepared in different locations.
3. The method according to claim 2,

A mold provided with an intermediate surface having the same separation distance from the outer surface in the vertical direction between the first inclined surface and the second inclined surface.
10. The method according to any one of claims 2 to 9,

The body is

a pair of long side members each extending in one direction and installed to face each other in a direction crossing the extending direction; and

A pair of short-side members each extending to intersect the long-side member and installed to face each other to seal between the pair of long-side members;

The first and second inclined surfaces are provided on the inner surface of at least one of the short side member and the long side member.
11. The method of claim 10,

The pair of short-side members are installed to be inclined so that the separation distance decreases toward the lower side,

A mold in which a side surface of the short side member in contact with the long side member is inclined toward the center of the width direction of the short side member toward the lower side.
11. The method of claim 10,

The body is a mold including a protrusion member formed to protrude toward the inner space at both ends of the extending direction of the short side member so as to form a chamfered surface on the edge of the cast slab.
11. The method of claim 10,

and a convex member which is formed to protrude from the inner surface of at least one of the long side member and the short side member toward the inner space, and whose protrusion length from the inner surface toward the inner space decreases toward the lower side,

The width of the convex member is shorter than the width of the body.
14. The method of claim 13,

The height of the convex member is shorter than the height of the body.
14. The method of claim 13,

The convex member is formed extending from the upper end (P U ) of the inner surface of the body to a third point (P 3 ) spaced apart by a third distance (S 3 ),

The third distance (S 3 ) is longer than the first distance (S 1 ), and shorter than the second distance (S 2 ).
16. The method of claim 15,

The slope at which the protrusion length decreases as the convex member goes downward, the slope is changed based on the third inflection point (IP 3 ) between the upper end (P U ) and the third point (P 3 ) of the body,

In the convex member, the angle between the lower region and the outer surface of the third inflection point (IP 3 ) is greater than the angle between the upper region and the outer surface of the third inflection point (IP 3 ).
17. The method of claim 16,

The third inflection point (IP 3 ) is provided in plurality, and the plurality of third inflection points (IP 3 ) is between the upper end (P U ) of the inner surface of the body and the third point (P 3 ). Molds prepared in different locations.