JP2004034067A - Continuous casting mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an economical continuous casting mold for which the frequency of maintenance is reduced and the productivity is increased. <P>SOLUTION: The continuous casting mold has a mold body which consists of a metal having satisfactory thermal conductivity, and in which many water conveyance grooves 11 are provided on all over the rear face, and a support member 14 fixed to the rear face side of the mold body. In the mold, cooling water is allowed to flow to the water conveyance grooves 11 via a water feed part 14 and a water discharge part 16 provided on the support member 14, so that the mold body is cooled. In this case, the mold body on the side lower than the lower end position of the water conveyance grooves 11 is provided with a cooling passage 23 to cool the lower end part of the mold body. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a continuous casting mold that can cope with an improvement in casting speed.
[0002]
[Prior art]
Conventionally, a continuous casting mold (hereinafter, also simply referred to as a mold) 70 used in a continuous casting facility includes a pair of narrow cooling members 71 and 72 as shown in FIG. , 72 and a pair of wide side members 73 and 74 which are wide cooling members disposed between the bolts, bolts 75 are attached to both ends of the long side members 73 and 74 facing each other, and springs (not shown) It is the structure fixed with the nut 76 via.
The short side members 71 and 72 have the same configuration, and as shown in FIGS. 6A, 6B, and 7, respectively, a large number of, for example, ten water guide grooves 77 are provided in the vertical direction on the back surface side. And a back plate 80 (also referred to as a cooling box) which is an example of a support member fixed to the back side of the copper plate 78 by a bolt 79. And the industrial cooling water which is an example of a cooling water is poured into the water guide groove 77 through the drainage part 81 and the water supply part 82 which were each provided in the upper end part and lower end part of the backplate 80, and the copper plate 78 is cooled. Yes. Since an O-ring 83 is disposed between the copper plate 78 and the back plate 80 so as to surround the water guide groove 77, the drainage part 81, and the water supply part 82, water leakage from the continuous casting mold 70 is prevented. Can be prevented.
Also, the long side members 73 and 74 have the same configuration, the width of the copper plate 84 is longer than the width between the short side members 71 and 72, and the width of the back plate 85 fixed to the back side of the copper plate 84 is The long side members 73 and 74 are longer than the copper plate 84 and have the same configuration as the short side members 71 and 72 except that the number of bolts for fixing the copper plate 84 to the back plate 85 is larger than the short side members 71 and 72. It is.
A mold body 86 is constituted by the copper plates 78 of the short side members 71 and 72 and the copper plates 84 of the long side members 73 and 74.
[0003]
During the continuous casting operation, molten steel is poured from above the mold 70 (above the short side members 71 and 72 and the long side members 73 and 74), and initial casting of the slab as a product is performed by the mold 70, The solidified slab is continuously drawn from the lower part of the mold 70 at a constant speed.
Although the molten steel temperature poured into the mold 70 and the surface temperature of the slab at the outlet of the mold 70 differ depending on the operating conditions, the molten steel temperature is usually about 1500 ° C., and the surface temperature of the slab at the outlet of the mold 70 is 800 ˜1200 ° C. The inside of the slab here is in an unsolidified state, that is, in a liquid state.
[0004]
[Problems to be solved by the invention]
However, the above-described continuous casting mold 70 has the following problems.
As shown in FIG. 8, the temperature in the vicinity of the lower end of the copper plate 78 where the water guide groove 77 is not provided (about 20 mm from the lower end of the copper plate) rises to nearly 300 ° C., and the location of about 100 mm from the lower end of the copper plate 78. It is about 130 ° C. higher than the temperature of. For this reason, the O-ring 83 located at the lower end portion of the copper plate 78 is deteriorated, and water leakage from the continuous casting mold 70 may occur. Accordingly, it is necessary to increase the frequency of maintenance of the continuous casting mold 70, and there is a problem that the operation must be interrupted, so that workability is deteriorated. In addition, since the deterioration rate of the O-ring 83 is increased by increasing the temperature of the lower end portion of the copper plate 78, the replacement frequency of the O-ring 83 is increased, which is not economical.
In recent years, the casting speed has been increased in order to improve the efficiency of continuous casting work. In particular, the slab is about 1/3 to 1/2 of the slab thickness employed in many continuous casting facilities. With the advent of continuous casting machines equipped with thick molds, it has become possible to see casting speeds that are twice or three times higher than conventional casting machines. When the casting speed is increased in this way, the amount of heat extracted into the mold body increases proportionally, so the heat load on the mold body increases. Accordingly, since it is necessary to increase the frequency of maintenance of the continuous casting mold, there is a problem that workability is further deteriorated and productivity is deteriorated by interruption of work.
The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the frequency of maintenance of a continuous casting mold, increase productivity, and provide an economical continuous casting mold.
[0005]
[Means for Solving the Problems]
The continuous casting mold according to the present invention that meets the above-mentioned object is made of a metal having good thermal conductivity, and has a mold body provided with a number of water guide grooves on one side of the back surface, and is fixed to the back surface side of the mold body by attachment means. A continuous casting mold that cools the mold body by flowing cooling water through the water supply groove and the drainage section provided in the support member, and further from the lower end position of the water supply groove. A cooling passage is provided in the lower mold body to cool the lower end of the mold body. As described above, since the cooling passage is provided in the mold main body further below the lower end position of the water guide groove, the cooling of the lower end portion of the mold main body, which has not been provided with a cooling passage in the past and has not been sufficiently cooled, is performed. It can be done easily.
In the casting mold for continuous casting according to the present invention, it is preferable that a cooling water supply passage that communicates the water supply portion and the cooling passage is provided. This facilitates the supply of cooling water to the cooling passage.
[0006]
In the continuous casting mold according to the present invention, it is preferable that cooling holes communicating with the cooling passages are respectively provided at both ends of the mold body. Thereby, for example, the cooling water can be allowed to flow in correspondence with the arrangement position of the O-ring that improves the adhesion between the mold body and the support member.
In the continuous casting mold according to the present invention, the cooling hole is preferably provided with a cooling water discharge passage communicating with the drainage portion. Thereby, drainage of the cooling water supplied to the cooling passage becomes easy.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
1A is an explanatory view of the short side member of the continuous casting mold according to the first embodiment of the present invention, FIG. 1B is a sectional view taken along the line AA in FIG. 1A is a cross-sectional view taken along the line BB in FIG. 1A, FIG. 3A is a partially enlarged view of a long side member of a continuous casting mold according to the second embodiment of the present invention, and FIG. A) CC sectional view taken on the line of FIG. 4, and FIG. 4 is an explanatory view of the temperature distribution at the lower end of the copper plate according to the calculation example.
[0008]
As described above, the continuous casting mold according to the first embodiment of the present invention combines the short side member 10 that is a pair of narrow cooling members and the long side member that is a pair of wide cooling members. The short side member 10 is made of copper, which is an example of a metal having good thermal conductivity, and has a large number of water guide grooves 11 (in the present embodiment, on the back side). 10) and a back plate 14 (also referred to as a cooling box or a water box) which is an example of a support member fixed to the back side of the copper plate 12 by the attachment means 13. The copper plate 12 is cooled by flowing industrial water, which is an example of cooling water, into the water guide groove 11 through the water supply unit 15 and the drainage unit 16 provided. The long side member of the continuous casting mold has substantially the same configuration as the short side member 10 described above, and the mold body is constituted by the copper plate 12 of the short side member 10 and the copper plate of the long side member. As described above, since the long-side member is different only in the width of the short-side member 10, the description thereof will be omitted, and only the short-side member 10 will be described in detail below.
[0009]
As shown in FIGS. 1A, 1B, and 2, the copper plate 12 (for example, a thickness of about 10 to 100 mm) is screwed into the female screw portion formed on the copper plate 12 and the female screw portion. It is fixed to a back plate 14 made of, for example, stainless steel (for example, a thickness of about 50 to 500 mm) by attachment means 13 comprising a male screw 17 for fastening 14. In addition, a groove is formed in the peripheral part of the back plate 14 surrounding the water supply part 15, the drain part 16, and the water guide groove 11 of the copper plate 12. Adhesiveness with the back plate 14 is improved, and leakage of industrial water from the water guide groove 11 is prevented. Further, in order to attach the male screw 17, a seal washer 20 that can be waterproofed is disposed in advance in holes 19 (15 in the present embodiment) formed in the back plate 14, and from the portion where the male screw 17 is attached. Prevents industrial water leaks.
Thereby, as shown in FIG. 2, industrial water is uniformly supplied from the water supply port 21 provided in the lower water supply portion 15 of the back plate 14 to each water guide groove 11, and from the lower side to the upper side of the copper plate 12. The industrial water which flowed is discharged | emitted from the drain port 22 provided in the drainage part 16 of the upper side of the backplate 14, and the copper plate 12 is cooled.
[0010]
As shown in FIGS. 1B and 2, the depth D of the water guide groove 11 provided on the entire back surface of the copper plate 12 is, for example, about 1/3 to 2/3 of the thickness of the copper plate 12. Further, the water guide grooves 11 are substantially linear in the direction of flowing water, and are formed at a predetermined pitch (for example, about 10 to 40 mm).
A cooling passage 23 for flowing industrial water to the lower end portion of the copper plate 12 is provided on the copper plate 12 further below the lower end position of the water guide groove 11, that is, below the water supply portion 15. The cooling passage 23 is disposed at substantially the same height as the O-ring 18 disposed at the lower end portion of the back plate 14 (for example, about 15 to 30 mm from the lower end of the copper plate 12), and the cooling surface (surface) of the copper plate 12. ) 24 and the O-ring 18. The cooling passage 23 is provided substantially linearly across the width direction of the copper plate 12, and is provided in the copper plate 12 by attaching lids to both ends of the copper plate 12 after passing from one end to the other end. It has been. The shape of the cooling passage 23 is substantially circular in cross section, and the diameter thereof is, for example, about 1/3 to 2/3 of the depth D of the water guide groove 11.
[0011]
In the central portion in the longitudinal direction of the cooling passage 23, there are three cooling water supply paths 25 communicating with the water supply section 15, one between the adjacent water guide grooves 11, from the water supply section 15 to the cooling passage 23. It is provided in an inclined state. The cooling water supply path 25 is provided by perforating the copper plate 12. Thereby, industrial water can be easily supplied from the water supply unit 15 to the cooling passage 23 through a route different from the water guide groove 11.
At both ends of the copper plate 12, cooling holes 26 that are disposed at positions facing the O-rings 18 disposed at both ends of the back plate 14 and communicate with both ends of the cooling passage 23 are provided. The cooling holes 26 are also provided substantially linearly over the height direction of the copper plate 12 and are provided by attaching lids to both ends of the copper plate 12 after passing through from the upper end to the lower end. . In addition, the shape of the cooling hole 26 is also substantially circular in cross section, and the diameter thereof is, for example, about 1/3 to 2/3 of the depth D of the water guide groove 11.
[0012]
At the upper end of the cooling hole 26, a cooling water discharge path 27 communicating with the drainage part 16 is provided. The cooling water discharge path 27 has substantially the same structure as the cooling passage 23 and the cooling water supply path 25 provided at the lower end of the copper plate 12.
Thereby, the industrial water supplied from the water supply port 21 is supplied to the many water guide grooves 11 through the water supply unit 15, and is supplied to the cooling passage 23 through the cooling water supply passage 25. The industrial water that has flowed from the cooling passage 23 to the cooling hole 26 flows into the discharge portion 16 through the cooling water discharge passage 27, and flows from the discharge port 22 together with the industrial water that has flowed into the discharge portion 16 through the water guide groove 11. Discharged.
Thus, since industrial water can be flowed into the copper plate 12 substantially corresponding to the location of the O-ring 18, deterioration of the O-ring 18 can be suppressed. In particular, since the lower end of the copper plate 12 that has not been conventionally cooled can be cooled, leakage of industrial water from the continuous casting mold can be prevented.
[0013]
Subsequently, a continuous casting mold according to the second embodiment of the present invention will be described. This is a long side member of the continuous casting mold, and the continuous casting according to the first embodiment of the present invention. Since the same member as the short side member 10 of the casting mold is also used, the same member is denoted by the same reference numeral and detailed description thereof is omitted. In addition, since this long side member is the shape which became line symmetrical with respect to the center line of the width direction of a long side member, only the right side part is demonstrated from the width direction center part of a long side member.
As shown in FIG. 3, after the cooling water supply path 32 for flowing industrial water through the cooling passage 31 passes through from the lower end of the copper plate 30 to the water supply unit 15 at the center in the width direction of the lower end of the copper plate 30. The copper plate 30 is provided by attaching a lid 32a to the lower end thereof. One end portion of the cooling passage 31 provided from the central portion in the width direction of the lower end portion of the copper plate 30 to the end portion is communicated with the central portion of the cooling water supply path 32. The cooling passage 31 is provided in the copper plate 30 by passing through the right end of the copper plate 30 and then attaching a lid 32b to the right end portion. The cooling passage 31 is disposed at substantially the same height as the O-ring 18 disposed at the lower end portion of the back plate 33 having the same effect as the back plate 14 (for example, about 15 to 30 mm from the lower end of the copper plate 30). Moreover, it is provided between the cooling surface (surface) 34 of the copper plate 30 and the O-ring 18. In addition, the shape of the cooling passage 31 is substantially circular in cross section, and the diameter is, for example, about 1/3 to 2/3 of the depth of the water guide groove 11.
[0014]
A cooling hole 35 communicating with the other end of the cooling passage 31 is provided at the end of the copper plate 30 at a position of, for example, about 3 to 10 mm from the back surface of the copper plate 30. The cooling hole 35 is arranged on the right side of the male screw 17 provided at the end of the copper plate 30 on the center side in the width direction of the copper plate 30 with respect to the arrangement position of the O-ring 18 arranged at the end of the back plate 33. ing. Here, the cooling hole 35 is provided in the copper plate 30 by drilling from the lower end of the copper plate 30 and attaching a lid 35a to the lower end portion thereof. A water guide groove 36 having the same width and depth as the water guide groove 11 is provided on the back side of the copper plate 30 on the right side of the male screw 17. Since the water guide groove 36 has a structure that is not directly connected to the water supply unit 15, the length thereof is shorter than that of the water guide groove 11. For this reason, the cooling hole 35 is provided in communication from the other end of the cooling passage 31 to the lower end of the water guide groove 36. Thereby, since it becomes unnecessary to provide a continuous cooling hole from the lower end to the upper end of the copper plate 30, manufacture becomes easy.
As a result, the industrial water flowing from the water supply unit 15 into the cooling passage 31 via the cooling water supply passages 32 flows from the central portion in the width direction of the lower end portion of the copper plate 30 to both ends, and is introduced into the water through the cooling holes 35. It flows into the groove 36. Accordingly, the lower end portion of the copper plate 30 can be cooled more efficiently.
[0015]
(Calculation example)
The result of the temperature analysis of the lower end portion of the copper plate using the continuous casting mold according to the present invention in which the cooling passage is provided in the mold body further below the lower end position of the water guide groove will be described with reference to FIG. . In addition, the O-ring is provided in a place where the distance from the lower end of the copper plate is about 10 mm, and the water supply part for industrial water is provided in a place from 20 mm to 80 mm.
There are two places where the temperature analysis is performed: the front surface side (present invention ●, conventional ◆) of the copper plate in the width direction and the rear surface side (present invention ▲, conventional ■) of the center in the width direction of the copper plate.
The temperature on the surface side of the copper plate of the continuous casting mold that has not been provided with a cooling passage is 289 ° C. in the vicinity of the position of the O-ring. Moreover, although the back surface temperature is lower than the front surface temperature, it is 205 ° C. at the position of the O-ring, and it can be seen that the temperature has risen to a temperature at which the O-ring is easily damaged.
[0016]
On the other hand, by providing a cooling passage at the lower end of the copper plate as in the continuous casting mold of the present invention, the surface side temperature is approximately the same as that of the conventional continuous casting mold in the vicinity of the lower O-ring. It can be seen that the temperature can be lowered by about 70 ° C., and can be greatly reduced to about 223 ° C. even at the highest place. The back surface temperature was 129 ° C. at the position of the lower O-ring, which was 76 ° C. lower than the conventional continuous casting mold.
From this, it can be seen that by using the continuous casting mold of the present invention, the lower end portion of the mold body can be efficiently cooled as compared with the conventional continuous casting mold. This is economical because the continuous casting mold can be used in a longer and better condition than before.
[0017]
As described above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the configuration described in the above embodiment, and the matters described in the scope of claims. Other embodiments and modifications conceivable within the scope are also included. For example, the present invention is also applied to the case where the continuous casting mold of the present invention is configured by combining some or all of the above-described embodiments and modifications.
[0018]
【The invention's effect】
In the casting mold for continuous casting according to claims 1 to 4, since the cooling passage is provided in the mold body further below the lower end position of the water guide groove, there is no conventional cooling passage and sufficient cooling is performed. The lower end portion of the mold body that has not been present can be easily cooled. Thereby, since deterioration of the O-ring located at the lower end of the mold body can be suppressed, the occurrence of water leakage from the continuous casting mold can be suppressed. Therefore, since the frequency of maintenance of the continuous casting mold can be reduced, workability is improved. In addition, since the temperature rise at the lower end of the mold body can be suppressed as compared with the conventional one, the deterioration rate of the O-ring is also slower than the conventional one, and the replacement frequency of the O-ring can be reduced, which is economical.
In addition, even when the casting speed is increased, the heat load on the lower end of the mold body can be reduced, and workability and productivity can be improved, so that the casting mold can be used for higher casting speeds. Can provide.
In the continuous casting mold according to the third aspect, for example, the cooling water can be caused to flow in correspondence with the arrangement position of the O-ring that improves the adhesion between the mold body and the support member. Therefore, since the deterioration of the O-ring arranged between the mold body and the support member can be further suppressed, the maintenance frequency of the continuous casting mold can be reduced, workability can be improved, and productivity can be improved. it can.
[Brief description of the drawings]
FIG. 1A is an explanatory view of a short side member of a continuous casting mold according to a first embodiment of the present invention,
(B) is AA arrow sectional drawing of (A).
FIG. 2 is a cross-sectional view taken along the line BB in FIG.
3A is a partially enlarged view of a long side member of a continuous casting mold according to a second embodiment of the present invention, and FIG. 3B is a cross-sectional view taken along the line CC in FIG.
FIG. 4 is an explanatory diagram of a temperature distribution at the lower end of a copper plate according to a calculation example.
FIG. 5 is a plan view of a continuous casting mold.
6A is an explanatory view of a short side member of a continuous casting mold according to a conventional example, and FIG. 6B is a cross-sectional view taken along line DD of FIG.
7 is a cross-sectional view taken along the line E-E in FIG.
FIG. 8 is an explanatory diagram of a temperature distribution of a copper plate.
[Explanation of symbols]
10: short side member, 11: water guide groove, 12: copper plate, 13: attachment means, 14: back plate (support member), 15: water supply unit, 16: drainage unit, 17: male screw, 18: O-ring, 19: Hole, 20: seal washer, 21: water supply port, 22: drainage port, 23: cooling passage, 24: cooling surface, 25: cooling water supply channel, 26: cooling hole, 27: cooling water discharge channel, 30: copper plate, 31: cooling passage, 32: cooling water supply passage, 32a, 32b: lid, 33: back plate, 34: cooling surface, 35: cooling hole, 35a: lid, 36: water guide groove

Claims (4)

The mold body is made of a metal having good thermal conductivity, and has a plurality of water guide grooves on one side of the back surface, and a support member fixed to the back surface side of the mold body by attachment means. In the continuous casting mold for cooling the mold body by flowing cooling water through the water guide groove through the water supply section and the drainage section provided,
A casting mold for continuous casting, wherein a cooling passage is provided in the mold body further below the lower end position of the water guide groove to cool the lower end portion of the mold body. 2. The continuous casting mold according to claim 1, further comprising a cooling water supply path that communicates the water supply section with the cooling passage. 3. The continuous casting mold according to claim 1, wherein cooling holes communicating with the cooling passage are respectively provided at both ends of the mold body. 4. template. 4. The continuous casting mold according to claim 3, wherein the cooling hole is provided with a cooling water discharge passage communicating with the drainage portion.

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