KR20180120440A - High efficiency cooling plate for casting mold and its manufacturing method - Google Patents

Abstract

The present invention relates to a manufacturing method for a high efficiency cooling plate for a casting mold and a mold thereof, more specifically, wherein a circular cooling hole is changed into an oval shape to provide a long cooling hole with improved cooling performance in case of distribution of cooling water for the shape of an oval hole is determined with a ratio between a transverse length and a vertical length, displaying 10.b >= a >= 2.b. The manufacturing method comprises: an ingot preparation process of preparing an ingot having the shape of a plate by melting and casting a copper alloy such as phosphorus deoxidized copper, CuAgP, or CuCrZr with excellent heat conductivity at a high temperature; a cooling forming process of forming a cooling hole in a longitudinal direction when forming a casting mold in the prepared ingot; a deformation material filling process of filling a deformation material to be finished to prevent damage by forming a deformed shape, irregular shape, hole, or divot except for the purposed shape of the cooling hole while inducing deformation of the purposed shape in the cooling hole; a deformation process of pressurizing a cooling plate to be deformed to have a purposed length and a width; and a deformation material removing process of removing a deformation material filled in the cooling hole of the cooling plate that has been finished.

Description

TECHNICAL FIELD [0001] The present invention relates to a high-efficiency cooling plate for a casting mold, and a manufacturing method thereof. BACKGROUND OF THE INVENTION < RTI ID =

The present invention relates to a high-efficiency cooling plate for a casting mold and a manufacturing method thereof, and more particularly to a high-efficiency cooling plate for a casting mold configured to form a shape of a cooling hole for circulating cooling water in a cooling plate of a casting mold .

In general, a casting mold is a frame formed as a fixed space for injecting molten metal at a high temperature to solidify the ingot to form an ingot, and it is constituted of an assembled or integrated cooling plate, and is a very important factor determining the quality and productivity of the ingot.

The casting molds are classified into various types such as ingot casting, continuous casting and shape casting according to the casting method, and ingot casting is a general casting method in which the molten metal is poured into a solid-phase ingot case to solidify the molten metal to form a steel ingot Followed by rolling or crushing to obtain the final product.

Continuous casting is carried out by a process of injecting molten metal directly into a water-cooled mold and continuously cooling the molten metal from the solidified portion to continuously produce a long-shaped casting (melting-molding-solidification). Thus, a final casting of a length of several meters to several tens of meters can be cast.

As compared with the ingot casting with slow cooling and solidification, the molten metal injected from the upper side of the mold having the upper and lower surfaces opened and the relatively shallower (shorter) length is lowered, and the cooling progresses and is discharged continuously to the lower side of the mold in a solidified state By controlling the solidification speed and the peripheral velocity, the gas or the residue discharged in the solidification process of the molten metal moves to the upper side of the mold, so that it is possible to obtain a high-quality long-form final casting containing no bubbles or impurities and advantageous for mass production And it is widely used.

Since the casting mold generally has a separate cooling means for cooling the molten metal, the initial solidification process, which produces the solidification layer through cooling by contact between the melt and the mold, directly affects the quality of the final casting, A cooling means is provided in order to effectively derive the cooling water.

In particular, in the case of a mold for continuous casting, it is necessary to configure the mold so that the molten metal is uniformly and wholly uniformly cooled during the process of passing through the mold, but the quality of the final casting can be assured and the life of the mold can be extended It is self-evident that it also has a profound effect on productivity.

In consideration of this point, techniques for increasing the cooling performance of the casting mold by various methods have been developed and used. The applicant of the present application also applied for the patent (2016 - 42689) in advance.

An ingot forming step of forming an ingot for molding by melting and casting the alloy, and then cutting the upper and lower portions to form an ingot;

A first hot working step of hot working the ingot at a temperature of 650 to 980 占 폚 at a reduction ratio of 30% or more to remove the cast structure and homogenize the same with equiaxed texture;

A cutting step of cutting the hot-worked ingot to form a short-circuit mold cooling plate and a long-circuit mold cooling plate;

A cooling hole forming step of cutting a plurality of cooling holes in the longitudinal direction of each of the short-circuit mold cooling plate and the long-circuit mold cooling plate, and cutting a predetermined portion of the top and bottom surfaces;

The cross-sectional shape of the cooling hole is parallel or parallel to the transverse direction while the thickness is compressed and the length is extended by rolling or drawing the cross-sectional reduction rate of 20 to 80% In the form of a figure including at least one horizontal line which is at least one horizontal line extending from the center of the mold.

Patent Application No. 10 - 2016 - 42689 Patent No. 10 - 1029898 Registration No. 10 - 0685474

In the above conventional technique, a cooling hole is formed in the ingot so as to penetrate the core, an elliptical metal core material is inserted into the cooling hole, and the ingot is rolled so that the cooling hole has an elliptical shape to increase the surface area of the cooling water. And to improve performance.

However, the core plate is obtained by inserting a core material having a size substantially equal to the inner diameter of the cooling hole formed substantially through the ingot or smaller than the inner diameter, and then rolling the ingot to increase the length of the ingot. However, It is practically difficult to separate the core material without damaging the cooling holes formed in an elliptical shape by making close contact closely.

That is, since the ingot and the core are in close contact with each other and the core of the ingot has a length of at least several meters, if the ingot is mechanically pulled at one side of the core while the ingot is fixed, And the core material can not overcome the frictional force and is cut in the middle, so that the actual core material can not be completely and cleanly removed, and as a result, it becomes difficult to obtain the cooling plate as a whole.

Particularly, in the process of removing the core material, it is difficult to remove the core material when the core material remains in an intermediate position of the cooling hole, and it is difficult to remove the core material by a method such as drilling. However, The cooling holes are damaged in this process. As a result, it becomes difficult to obtain a cooling plate capable of maintaining excellent quality in a uniform state.

In such a conventional technique, it is possible to obtain a long-length cooling plate having an elliptical cooling hole which can not be formed by drilling by changing the circular cooling hole to an elliptical shape. In reality, however, It is not free from problems such as the fact that it can not maintain uniform quality while lowering the cost and mass production becomes impossible.

Accordingly, the present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide an ingot preparation process for preparing a plate-shaped ingot by dissolving and casting a copper alloy having excellent thermal conductivity or a copper alloy such as CuAgP or CuCrZr at a high temperature; A cooling hole forming process for forming a cooling hole in a cast ingot mold to a prepared ingot; A deformation material to fill the deformation material into the cooling hole to induce the deformation into the desired shape while preventing the cooling hole from being deformed to a shape other than the desired shape or to prevent irregular shape, A filling process; A deformation process in which the cooling plate is deformed by pressing so as to have a desired length and width; And a deformation material removing step of removing the deformation material filled in the cooling holes of the cooling plate after the deformation has been completed;

It is possible to substantially maintain the shape of the cooling holes while allowing a substantial mass production of the cooling plate having the long oval cooling holes and to provide a cooling plate having excellent and uniform quality and to improve the overall productivity and the production cost It is possible to achieve the purpose of enabling reduction.

The present invention provides a means for completely securing a cooling hole in a deformed state while deforming a cooling hole having a long length and a short length formed in the ingot into an elliptical shape having a long length by rolling the ingot, It is possible to easily and cleanly remove filler material by melting, removing, or removing chemical material, not by the core material, thereby rolling the plate, thereby improving the productivity of the cooling plate and reducing the production cost, .

It is possible to make a stable change in the process of deforming the cooling holes from a circular shape to an elliptical shape in a short length to a long length and to facilitate the removal of the deformation material after the deformation is completed, It is possible to maintain the quality of the excellent and uniform state without damage.

The elliptic cooling holes to which the technology of the present invention is applied have a larger hydraulic diameter as compared with the conventional circular cooling holes having the same cross sectional area and can increase the heat transfer coefficient depending on the shape, Effect can be obtained.

1 is a process block diagram showing a manufacturing process of a cooling plate for a casting mold to which the technique of the present invention is applied.
Fig. 2 is a process chart showing a manufacturing process of a cooling plate for a casting mold to which the technique of the present invention is applied.
Fig. 3 is an illustration showing a cooling plate for a casting mold completed by the technique of the present invention; Fig.
Fig. 4 is an illustration of a casting mold composed of a cooling plate completed by the technique of the present invention; Fig.
Fig. 5 is an illustration of a deformation state of a cooling hole formed in a cooling plate according to the technique of the present invention; Fig.
6 is an exemplary view for examining the thermal-structural behavior of a cooling plate according to the shape of a cooling hole of a circular shape and an elliptical shape;
7 is an illustration of a change in heat transfer coefficient of circular and elliptical cooling hole cooling plates of the same cross-sectional area;
8 is an illustration of the temperature distribution of a cooling plate having a circular cooling hole;
9 is an illustration of the temperature distribution of a cooling plate having an elliptical cooling hole;
10 is an illustration of a deformation distribution of a cooling plate having a circular cooling hole;
11 is an illustration of a deformation distribution of a cooling plate having an elliptical cooling hole;

Hereinafter, a method of manufacturing a cooling plate according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a process block diagram showing a manufacturing process of a cooling plate for a casting mold to which the technique of the present invention is applied, FIG. 2 is a process diagram showing a manufacturing process of a cooling plate for a casting mold to which the technique of the present invention is applied, Fig. 4 is an exemplary view of a casting mold constituted by a cooling plate completed by the technique of the present invention, Fig. 5 is a view showing an example of a cooling plate for a casting mold completed by the technique of the present invention, The following description will be made together with an example of a deformation state of the formed cooling holes.

The cooling plate 100 for a casting mold to which the technique of the present invention is applied may be configured to have a desired shape such as a square shape or a rectangular shape in cross section and cooled (cooled) while passing the melt 101 between the cooling plates 100 The cooling plate 100 is provided with a cooling hole 110 for circulating cooling water so that the melt 101 can be uniformly and rapidly cooled.

The present invention provides a novel method of making the cooling plate 100 having the cooling holes 110 capable of maximizing the cooling efficiency, thereby improving the productivity and reducing the cost and improving the quality.

In order to achieve the above object, the present invention provides a method for manufacturing a cooling plate for a casting mold, comprising the steps of melting a copper alloy having excellent thermal conductivity or a copper alloy such as CuAgP or CuCrZr at a high temperature of about 1120 to 1180 DEG C, A cooling hole forming process S200 for forming a cooling hole 110 so as not to penetrate the prepared ingot 111 and a cooling hole forming process S200 for forming a cooling hole 110, The cooling hole 110 may be deformed into a shape other than the desired shape or deformed to prevent irregular shape or damage such as a hole or a divot being formed while inducing deformation of the cooling hole 110 into a desired shape (preferably elliptical shape) A deformation process S400 for deforming the cooling plate 100 so as to have a desired length and width by pressing and deforming the cooling plate 100 and a deformation process S400 for deforming the cooling plate 100 ) Cold It comprises a modified material removal process (S500) of removing the strain material 120 filled in the hole 110.

The ingot preparing process S100 may be a direct production of a plate-shaped ingot made of copper or a copper alloy material. However, recently, a ready-made manufactured product meeting the requirements of the desired use, size shrinkage, It is possible to use it, so avoid the specific reference to this.

The cooling hole forming process S200 forms a cooling hole 110 in the longitudinal direction when the casting mold 105 is formed using the cooling plate 100. [

The diameter d and the depth D of the cooling hole 110 are mathematically calculated in consideration of the final length, width and thickness of the cooling plate 100 and the cooling efficiency to be performed by circulating the cooling water, And the intervals for arranging the cooling holes 110 in the width direction of the cooling plate 100 as well as the number of the cooling holes 110 may also be the same.

The deformation material filling process S300 is performed such that the deformation material 120 is filled in the cooling hole 110 to induce a stable deformation of the cooling hole 110 into a desired shape in the process of deforming the cooling plate 100 .

The deformation member 120 may be formed by filling a material having a melting temperature lower than the melting temperature of the ingot 111, such as lead, or a chemical material such as a powder material such as sand, metal powder, ceramic powder, Materials and the like.

When the operation of filling the deformation member 120 into the cooling hole 110 is completed, the cooling hole 110 is closed so that the deformation member 120 does not flow out, Bolt-on, weld-finish, and the like, and it will be appreciated that it is sufficient to withstand the high pressure and high temperature of the subsequent deformation process (S400).

In the modification process (S400), the cooling plate (100) filled with the deformation member (120) in the cooling hole (110) is rolled to a reduction ratio of 20 to 80% And compresses the cross-sectional shape of the substrate 110 to be close to an elliptical shape.

A (width) = b (length) in the case of a circle, R (diameter) = a (width) ) (See Fig. 5). That is, if the length a = 40, the vertical length is 4 ~ 20. In this process, the length of the cooling plate 100 can be extended up to 5 times.

That is, when the deformation member 120 is filled with the circular cooling hole 110 and deformed by rolling or the like, the cooling plate 100 is outwardly long, wide, and low in thickness And the cooling holes 110 formed therein are deformed from the garden shape to the elliptical shape as shown in Fig. 5 without any phenomenon such as irregular collapse due to the deformation member 120. Fig.

As a result, as the cooling plate 100 is deformed, the cooling hole 110 is also deformed to form a circular cooling hole, so that the cooling surface area acting on the casting mold during circulation of the cooling water can be increased, Which is already mentioned in the contents of the earlier application.

Of course, it is a matter of course that the rate of change of the cooling plate 100 can also be varied numerically depending on the use or kind of the casting mold, and the like, so that the present invention is not limited thereto.

The deformation material removing process S500 may be performed such that the deformation material 120 filled in the cooling hole 110 is removed after the deformation of the cooling plate 100 to allow the cooling water to flow. Both sides of the cooling plate 100 are cut so that the cooling holes 110 are exposed.

In this state, the deformation member 120 filled in the cooling hole 110 may be removed. If the deformation member 120 is a fusible material, the deformation member 120 is heated to a temperature at which the deformation member 120 is melted, The deformation removing member 120 may be removed.

When the deformation member 120 is filled with a powder material such as sand, metal powder, ceramic powder or the like, a drill or vibration pin is inserted into the cooling hole 110, or the cooling plate 100 is fixed in the longitudinal direction, The deformation member 120 may be removed from the cooling hole 110 by mechanical removal.

Of course, after the deformation member 120 is removed, a post-processing tool such as a brush is inserted into the cooling hole 110 to completely remove the residual deformation member 120 to smooth the surface of the cooling hole 110, It is also obvious that it does not cause any disruption to the distribution of

When the deformation member 120 filled in the cooling hole 110 is a chemical material such as a fluid having chemical properties, chemical removal may be performed to separate the deformation member 120 from the cooling hole 110 using a chemical agent.

In the present invention as described above, the operation of forming the cooling holes in the cooling plate can be facilitated in comparison with the conventional method using the core material, thereby improving the overall productivity and reducing the production cost, thereby reducing the manufacturing cost of the entire casting mold can do.

Further, the deformation member filled in the cooling hole can stably induce the deformation of the cooling hole, and the deforming agent can be easily removed after the deformation is completed, so that the cooling hole can be maintained normally through a post- Can be solved.

The heat-structure analysis according to the cross-sectional shape of the cooling hole was performed for an ESR mold having a length of 1000 mm, a length of 600 mm and a length of 3200 mm manufactured by the technique of the present invention.

At this time, the effective cooling distances were all the same and the cross-sectional areas of the cooling holes were also analyzed under the same conditions (Fig. 6). The material of the mold plate is silver copper (CuAg0.1).

Item     CuAg-GS

Density [kg / m3]     890

Specific Heat [J / kg? K]     86

Thermal Conductivity [W / mK]     77

Poisson Ratio     31

Elastic Modulus [GPa]     25

Thermal Expansion Coefficient [10-6 / C]     17.7

Yield Strength [MPa]     280

Plastic Modulus [GPa]     1.1

At this time, the heat transfer coefficient of the elliptical hole mold plate was about 4% higher than that of the elliptical hole mold plate due to the difference in the hydraulic diameter according to the shape difference even though the cross-sectional area of the cooling hole was the same (FIG.

Therefore, the maximum temperature of the circular hole mold plate and the maximum temperature of the elliptical hole mold plate are different by about 30 캜 (Figs. 8 and 9).

As a result, the elliptical hole mold plate having a relatively low maximum temperature showed a deformation amount of the mold plate by about 20% as compared with the circular hole (Figs. 10 and 11).

These changes are attributed to the extension of the life of the casting mold in the actual operation, and at the same time, the cooling ability is improved, so that it is possible to increase the speed of the casting, thereby enhancing the productivity of the product and positively affecting the quality of the ingot.

In the present invention as described above, when the deformation material is filled in the cooling hole, the circular cooling hole is changed to an elliptical shape in the course of deformation, so that the cooling water passed when the cooling hole is completed has a elliptical cross- The cooling performance of the holes is increased and finally the heat exchange property with the castings formed by the casting molds is maximized to cool the castings uniformly and rapidly so that the quality of the manufactured products can be improved while providing ease of manufacture, .

100; Cooling plate
110; Cooling hole
120; Deformation material

Claims (4)

The amount of deformation of the cooling plate due to the increase in the cooling capacity due to the difference in the hydraulic diameter in the same cooling condition as that of the cooling plate having the same cross-sectional area and the same number of the circular cross- Constituting a cooling plate;
Characterized in that the shape of the elliptical cooling hole of the cooling plate satisfies the condition of 10.b? A? 2b. In manufacturing the cooling plate 100 for a casting mold,
(S100) preparing an ingot 111 in the form of a plate by dissolving and casting copper having high thermal conductivity or a copper alloy such as CuAgP or CuCrZr at a high temperature;
A cooling hole forming step (S200) of forming a cooling hole (110) in the longitudinal direction when the cast ingot mold is prepared on the prepared ingot (111);
It is possible to prevent the cooling hole 110 from being deformed into a shape other than a desired shape or to prevent irregular shape or damage such as a hole or a divot being formed while inducing deformation into a desired shape in the cooling hole 110 120) and finishing the filling material (S300);
A deformation process (S400) of pressing and deforming the cooling plate (100) so as to have a desired length and width;
(S500) for removing the deformation member (120) filled in the cooling hole (110) of the cooling plate (100) after the deformation is completed. 3. The method of claim 2,
The deformation member 120 to be filled in the cooling hole 110 in the deformation re-filling step S300 may be any one of a molten material, a powder material, and a chemical material having a melting temperature lower than the melting temperature of the ingot 111 Characterized in that the cooling plate is made of a metal. 3. The method of claim 2,
The deformation material removing process S500 may include melting removal to heat and remove the deformation material 120 of the molten material filled in the cooling hole 110 to a temperature at which the material is melted and drilling or removing the powder material filled in the cooling hole 110 Mechanical removal to remove vibration and chemical removal to remove the chemical material filled in the cooling hole (110) using a chemical agent.

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