JPH0852537A - Mold wall of mold for continuous casting - Google Patents

Abstract

PURPOSE:To provide the mold wall which is improved in cooling capacity of the whole mold wall, further can easily be machined and is reduced in a production cost. CONSTITUTION:A copper plate 1 is fitted to a backplate with a fitting bolt, plural slit grooves 2a-2h, which are opened on its rear, grooved toward the front side and having groove bottom part within thickness, are vertically formed. An opening side pitch of respective slit grooves 2a-2h is made wide at the part to sandwich a screw hole 10 for fitting bolt and thermocouple fitting hole 11 in between and narrow at the part not sandwiching the screw hole 10 and the hole 11 in between two slit grooves 2a.2b and 2g.2h constituting a wide opening side pitch are formed to an incline groove so as to approach each other inward as proceeding from an opening part to a groove bottom, and groove bottom side pitches of respective slit grooves are made equal with each other. By this method, cooling is uniformly executed over the whole face of copper plate 1.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a mold wall in a mold for continuous casting. A general mold for continuous casting is composed of a pair of long-side frames and a pair of short-side frames sandwiched between the long-side frames in a box shape, in which molten steel is cast and cooled. It is configured to be pulled out. As shown in FIG. 3, each mold wall is composed of a copper plate 1 on the side in contact with molten steel and a back plate 3 supporting the same, and a large number of slit grooves 2 are formed on the back surface of the copper plate 1 in the vertical direction. Then, the cooling water is made to flow from the bottom to the top in the slit groove 2 to cool the copper plate 1. The above configuration is basically the same on the short side and the long side, and the present invention relates to the mold wall according to the basic configuration.

[0002]

2. Description of the Related Art With the development of high-speed casting technology, the heat load on the mold wall is increased, resulting in delamination due to heat, shortening of mold life, and problems such as breakout and vertical cracking due to thermal deformation. It tends to occur. As a conventional technique that considers cooling of a mold wall, there is Japanese Utility Model Publication No. 2-17732 (conventional example I).
This Conventional Example I will be described with reference to FIGS. 4 to 5, 51 is a copper plate, 53 is a back plate, 54 is an O-ring for sealing,
The copper plate 51 and the back plate 53 are connected by bolts 59. A plurality of slit grooves 52 are vertically formed on the back surface of the copper plate 51, and an oblique slit groove 58 inclined outward is further formed on the outermost side. In this conventional example I, the diagonal slit groove 58 improves the cooling ability of the corner portion. FIG. 6 shows a short side mold wall constructed based on the technical idea of the conventional example I. The corner portion is improved in cooling capacity by the oblique slit groove 58, but although a plurality of slit grooves 52 are formed in the portion excluding the corner portion, they are not all at equal intervals, and the mounting bolt The slit groove pitches A and B sandwiching the mounting screw holes 55 and the temperature measurement thermocouple mounting holes 56 are larger than the slit groove pitch C of the portions not sandwiching the screw holes 55 and the mounting holes 56. ing. Therefore, cooling of a portion having a large pitch is not sufficient, and it is still impossible to sufficiently prevent troubles such as a shortened mold life and breakout and vertical cracks due to thermal deformation.

FIG. 7 shows a subsequently proposed JP-A-2-59.
The technique of Japanese Patent Publication No. 144 (conventional example II) is shown. This Conventional Example II is intended to improve the cooling capacity of the parts other than the corners, and the shape of the slit groove 52 within 100 mm from the vicinity of the meniscus of the mold wall should be adjusted to the slit around the screw hole 55 of the mounting bolt. While keeping the groove pitch wide,
The slit groove pitch is narrowed in the portion without the screw holes 55, that is, between the upper and lower screw holes 55, 55. Although this conventional example II was able to improve the cooling capacity in the vicinity of the meniscus, the cooling capacity below the vicinity of the meniscus was not yet improved, and again, the breakout due to the shortening of the mold life and thermal deformation, vertical cracking It was not possible to prevent such problems. Furthermore, this conventional example II
Then, the slit groove 2 must be formed by bending at the portion connecting the slit groove 52 having a large pitch to the slit groove 52 having a small pitch, and since the slit groove 2 has the bent portion 50, it is troublesome for machining. It took a lot of time and increased the number of manufacturing steps.

[0004]

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a mold wall which improves the cooling capacity of the entire mold wall, is easy to machine, and is inexpensive to manufacture.

[0005]

The mold wall of the present invention comprises:
A copper plate is attached to the back plate with mounting bolts, and the copper plate has a plurality of slit grooves formed in the vertical direction, which are opened at the back surface and are dug down toward the surface side, and the groove bottom portion is present within the wall thickness. The opening side pitch of each slit groove that is a wall is wide in a portion that sandwiches a screwing hole for a mounting bolt or a thermocouple mounting hole, and is narrow in a portion that does not sandwich the screwing hole or the mounting hole. The two slit grooves forming the wide opening side pitch are formed in inclined grooves so that they approach each other inwardly from the opening toward the groove bottom, and the slit bottom side pitch of each slit groove is made equal. And Further, the present invention is characterized in that the depths of the slit grooves in the direction perpendicular to the back surface of the copper plate are the same.
The mold wall described above can be applied to both the long side and the short side, but as the mold wall on the short side, it is preferable that only the slit grooves at the corners are inclined to the outside of the corners.

[0006]

In the present invention, since the groove bottoms of the slit grooves through which the cooling water passes are located at an equal pitch within the copper plate, the surface of the copper plate in contact with the molten steel is cooled uniformly. When the slit grooves have the same groove depth in the direction perpendicular to the back surface of the copper plate, the cooling is performed more uniformly. Therefore, thermal deformation does not easily occur in the copper plate, and problems such as breakout and vertical cracks are eliminated. Further, even if the slit groove is inclined in the depth direction from the opening side to the groove bottom, this inclination does not make cutting by machining difficult, and the longitudinal direction of the slit groove is a straight line. It is easy to manufacture and can be manufactured at low cost. In the mold wall on the short side, if only the slit groove of the corner portion is inclined to the outside of the corner portion, the cooling capacity of the corner portion is improved. In this case, the effect of preventing breakout and vertical cracking of the slab due to the insertion of molten steel during casting is eliminated by eliminating the gap that tends to occur at the abutting surfaces of the long side mold wall and the short side mold wall.

[0007]

Embodiments of the present invention will now be described with reference to the drawings. 1 is a rear view of a copper plate 1 constituting a mold wall according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view taken along line II of FIG. In FIGS. 1 and 2, 10 is a screwing hole for a mounting bolt (for example, a stud bolt), and 11 is a mounting hole for a thermocouple. A heli-sert, which is a heat-insulating diamond-shaped coil spring-shaped reinforcing member, may be inserted into the screw hole 10. An appropriate number of screw holes 10 and mounting holes 11 are provided in the vertical direction.

Reference numerals 2a to 2h are slit grooves. The slit grooves 2a to 2h are opened at the back surface of the copper plate 1, are dug down toward the front surface side, and are formed so that the groove bottom portion exists within the wall thickness. The slit grooves 2a and 2b and the slit grooves 2g and 2h sandwich the screw hole 10, and the slit grooves 2d and 2e are mounting holes.
I'm holding 11 Also, slit grooves 2b and 2c and 2c and 2d
No space between them, slit grooves 2e / 2f and 2f / 2g
The same is true for the period. Slit groove 2b with no holes in between
The opening side pitch between 2c, 2c and 2d, 2e and 2f, and 2f and 2g is indicated by the symbol C, and the opening side pitch between the slit grooves 2a and 2b and 2g and 2b that sandwich the screwing hole 10 is shown. When the reference numeral A and the opening side pitch between the slit grooves 2d and 2e sandwiching the mounting hole 11 are shown by the reference numeral B, the opening side pitches A and B are larger than the opening side pitch C. In this way, on the back side of the copper plate 1,
Leave the thickness of the copper plate 1 around the screw holes 10 and the mounting holes 11,
The strength is not reduced.

Then, slit grooves 2a and 2b that sandwich the screwing hole 10 are formed.
Are formed into grooves that are inclined so as to approach each other inwardly from the opening toward the groove bottom. This is
The same applies to the slit grooves 2g and 2h that sandwich another screwing hole 10.
Further, the slit grooves 2d and 2e that sandwich the mounting hole 11 are also formed so as to be inclined toward each other inward from the opening toward the groove bottom. The slit grooves 2c and 2f are not inclined and are dug in a direction perpendicular to the back surface of the copper plate 1.

As a result of the above construction, each slit groove
The pitches between the groove bottoms of 2a to 2h (indicated by symbol D) are all the same. In other words, the depth direction of the slit grooves forming the wide opening-side pitches A and B must be inclined by a necessary angle so that all groove bottom-side pitches D are the same. Further, the depth h1 in the direction perpendicular to the back surface of the copper plate 1 in each slit groove 2a to 2h is the same. Therefore,
The distances h2 from the surface of the copper plate 1 to the groove bottoms of the slit grooves 2a to 2h are also the same. As a result, the cooling water passes through evenly-spaced portions of the copper plate 1 when viewed in the width direction, and the cooling water passes through all the portions equidistant from the surface of the copper plate 1, so that the entire copper plate 1 is cooled uniformly. Will be done.

In the short side mold wall shown in FIGS. 1 and 2, the slit grooves 8a, 8b on the outermost side, that is, the corners are formed.
Is preferably inclined toward the outside. In this case, the groove bottom may be formed closer to the end surface and the surface of the corner portion, so that the groove depth may be deeper than the slit groove 2. With this configuration, the corner portion of the short side mold wall can be cooled more effectively. However, it is not necessary to provide slit grooves corresponding to the above-mentioned corner slit grooves 8a and 8b on the long side mold wall.

The slit grooves 2a to 2h and 8a to 8b shown in FIGS.
Both are straight grooves when viewed in the longitudinal direction. Therefore, the slit groove can be easily formed by milling. Further, the slit grooves 2a, 2b, 2d, 2e, 2g, 2h that are inclined in the depth direction are also easy to process because the copper plate 1 may be inclined on the bed of the milling machine. Therefore, it can be manufactured at low cost.

[0013]

According to the present invention, the entire mold wall is evenly cooled to improve the cooling capacity, and it is possible to prevent the peeling of the plating and the shortening of the mold life due to heat, and the breakout and vertical cracking due to thermal deformation. The troubles can be well prevented. In particular, when the present invention is applied to the mold wall on the short side, it is possible to eliminate the gap between the mold wall on the long side and prevent breakout due to insertion of molten steel during casting and vertical cracking of the slab. Especially high. Further, according to the present invention, the mold wall can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a rear view of a short-side copper plate forming a mold wall according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line II of FIG.

FIG. 3 is an explanatory view of a general mold wall.

FIG. 4 is a cross-sectional view of a mold wall of Conventional Example I.

5 is a view taken in the direction of arrow V in FIG.

FIG. 6 is a rear view (A) of the copper plate on the short side mold wall using the technique of Conventional Example I and a sectional view (B) taken along the line B of FIG.

7A is a partial rear view of the copper plate on the mold wall of Conventional Example II, FIG. 7B is an enlarged sectional view taken along line B of FIG. 7A, and FIG.

[Explanation of symbols]

 1 Copper plate 2a ~ 2h Slit groove 3 Back plate 8a, 8b Slit groove 10 Screw hole 11 Mounting hole

Claims (3)

[Claims] 1. A copper plate is attached to a back plate with a mounting bolt, and a slit groove is formed in the copper plate, the slit groove having an opening at the back surface and being dug down toward the front surface side and having a groove bottom portion within the wall thickness.
A plurality of mold walls formed in the up-and-down direction, the opening side pitch of each slit groove is wide in the portion sandwiching the screw hole for the mounting bolt or the thermocouple mounting hole, and the screw hole or the mounting hole is sandwiched. The two slit grooves forming the wide pitch on the opening side are formed in a slanted groove so that they approach each other inward from the opening toward the groove bottom. A mold wall of a mold for continuous casting, which has the same bottom side pitch. 2. The mold wall of the continuous casting mold according to claim 1, wherein the depths of the slit grooves in the direction perpendicular to the back surface of the copper plate are the same. 3. The mold wall on the short side is characterized in that only the slit grooves at the corners are inclined to the outside of the corners, and the pitch at the groove bottom side is not equal to that of the other slit grooves. The mold wall of the mold for continuous casting according to 1.