JPS63220948A - Mold for continuously casting square shaped ingot - Google Patents

Abstract

PURPOSE:To obtain a square shaped ingot having uniform cooling effect and good quality by forming a mold by combining cylindrical graphite-made sleeve and metal backup. CONSTITUTION:The mold 10 for continuously casting the square shaped ingot has the cylindrical backup 12 formed by metal of copper or copper alloy, etc., and the integrated cylindrical graphite-made sleeve 14, of which outer circumference is cylinder shape and inner part hollowed out to the desired square shape. The backup 12 and the graphite-made sleeve 14 are combined by shrinkage fit or press fit. In this way, the uniform cooling effect is obtd. and the square shaped ingot having good quality without developing phenomenon of secondary melting, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold used when continuously casting metal or alloy ingots having a rectangular, non-round cross-sectional shape such as a rectangular, H-shaped, or ■-shaped cross-sectional shape. It is.

Bi1. I! i.

Conventionally, when continuously casting metal or alloy ingots with cross-sectional shapes that are not round, such as rectangular, H-shaped, or ■-shaped, they are cast as shown in FIGS. 5 and 6. molds were used. Briefly, such a continuous casting mold for rectangular ingots is usually made of copper or copper alloy, and has a through-hole of a desired shape, for example, a rectangular cross-section, along the axis. The mold is an angular mold with a predetermined taper in the direction, and the surface of the mold is plated or the like. When a mold is used for continuous casting of square ingots in this way, the outer periphery of the square ingots that are continuously cast inside the mold is not uniformly cooled, causing a phenomenon called "secondary melting." However, the quality of the appearance of the ingot deteriorated.

In order to solve this problem with molds, instead of using metals such as copper or copper alloys as the mold material, we used graphite to form graphite sleeves divided into multiple parts, and each graphite sleeve was connected with bolts. A method of manufacturing a mold by fixing it with etc. has been proposed. Additionally, molds with cooling wood tubes built into graphite molds have also been manufactured.

However, such a graphite mold has problems in that it is complicated to manufacture and the manufacturing cost is high.

As a result of numerous studies and experiments to solve this problem, the inventors of the present invention formed a cylindrical backup made of metal such as copper, and created a cylindrical backup with a cylindrical outer circumference and an interior. A mold made by inserting a graphite sleeve hollowed out into a desired square shape by shrink fitting or press fitting is extremely suitable for continuous casting of square ingots, and does not cause phenomena such as secondary melting, resulting in a good cast. It has been found that high quality prismatic ingots can be produced.

The present invention has been made based on this new knowledge.

The object of the present invention is to provide a mold for continuous casting of square ingots that can obtain a uniform cooling effect, do not cause phenomena such as secondary melting, and can produce square ingots of good quality. The goal is to provide the following.

Another object of the present invention is to provide a mold for continuous casting of square ingots that is simple in structure, easy to manufacture, and inexpensive to manufacture.

The above object is achieved by a mold for continuous casting of square ingots according to the present invention. In summary, the present invention includes a cylindrical backup made of metal such as copper or copper alloy, and a cylindrical graphite sleeve whose outer periphery is cylindrical and whose inside is hollowed out into a desired square shape. The continuous casting mold for rectangular ingots is characterized in that the backup and the graphite sleeve are integrally combined by shrink fitting or press fitting.

Next, a mold for continuous casting of square ingots according to the present invention will be explained in detail with reference to the drawings.

FIG. 1 and FIG. 2 illustrate an embodiment of the continuous casting mold for prismatic ingots according to the present invention.According to this embodiment, the continuous casting mold IO for prismatic ingots is made of copper or copper alloy, etc. It has a cylindrical backup 12 made of metal, and an integral cylindrical graphite sleeve 14 with a cylindrical outer periphery and a desired square hollowed out interior, in this example a rectangular shape, The backup 12 and the graphite sleeve 14 are assembled by shrink fitting or press fitting.

Of course, the cylindrical inner surface of the graphite sleeve will be formed with a predetermined taper from one end opening to the other end opening, and furthermore, the cross-sectional shape of the cylindrical inner surface of the graphite sleeve is limited to a rectangular shape. 1 for example 3rd instead of thing
It may have various angular shapes such as an H-shape as shown in the figure or an I-shape.

According to research experiments conducted by the present inventors, a mold for continuous casting of square ingots is manufactured by assembling a cylindrical metal backup and a graphite sleeve whose inside is hollowed out into a desired square shape by shrink fitting or press fitting. Although the reason for this is not clear, it is thought that the first reason is due to the cooling effect, but the outer shape of the graphite sleeve is either circular as mentioned above, or an elliptical shape that approximates a circle. It has been found that it is difficult to continuously cast square ingots in a rectangular shape as shown in FIG. 4. According to the invention, therefore, the cross-sectional shape of the cylindrical outer periphery of the graphite sleeve is circular or elliptical.

The cross-sectional shape of the cylindrical backup is such that the contact surface with the graphite sleeve is circular or elliptical in correspondence with the sleeve. Furthermore, if the outer shape of the backup 12 is a rectangle similar to that of the sleeve 14, uneven stress will occur during shrink fitting when the rectangular sleeve 14 is assembled into the rectangular backup 12, resulting in cracking of the sleeve or damage to the backup. It was also found that it was difficult to obtain a satisfactory cooling effect due to uneven contact between the sleeve and the sleeve.

140mmX using the mold according to the present invention as described above.
Continuous casting of 140 mm square steel ingots revealed that compared to conventional copper molds, there was no or very little occurrence of defects such as secondary melting and cracking, and products with good appearance could be obtained. , and the product yield was dramatically improved from 70% when using a copper mold to 90%.

Another advantage of the mold of the present invention is that rectangular ingots of various shapes can be manufactured by changing only the inner graphite sleeve without changing the metal backup.

11 vertical difference j As described above, the mold for continuous casting of square ingots according to the present invention is formed by a combination of a cylindrical graphite sleeve and a metal backup, so that a uniform cooling effect can be obtained. , without causing phenomena such as secondary dissolution,
It has the advantages of being able to produce square ingots of good quality, having a simple structure, being easy to manufacture, and having low manufacturing costs.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of a mold for continuous casting of square ingots according to the present invention. FIG. 2 is a plan view of the mold shown in FIG. 1. FIG. 3 is a plan view of another embodiment of the mold for continuous casting of square ingots according to the present invention. FIG. 4 is a plan view of a mold for continuous casting of undesirable square ingots. FIG. 5 is a sectional view of a conventional continuous casting mold for square ingots. FIG. 6 is a plan view of the mold of FIG. 5. 122 Metal back-up 14: Graphite sleeve

Claims (1)

[Claims] 1) A cylindrical backup made of metal such as copper or copper alloy, and a cylindrical graphite sleeve whose outer periphery is cylindrical and whose inside is hollowed out into a desired square shape. A mold for continuous casting of a rectangular ingot, characterized in that the backup and the graphite sleeve are combined together by shrink fitting or press fitting. 2) The cross-sectional shape of the cylindrical outer periphery of the graphite sleeve is circular or elliptical, and the cross-sectional shape of the square interior is rectangular, H-shaped, I-shaped, etc., and the cross-sectional shape of the cylindrical backup The mold according to claim 1, wherein the cross-sectional shape of the inner surface that contacts the cylindrical outer circumferential surface of the graphite sleeve is circular or elliptical in accordance with the cylindrical outer circumferential shape of the graphite sleeve.