JPH05212532A - Manufacture of complex steel ingot - Google Patents

Abstract

PURPOSE:To enable the manufacture of mainly a composite roll for rolling having high performance by using a rotation imparting ESR composite method giving rotation capable of the manufacture of a composite ingot freely combining an outer layer material and a core material and having excellent joinability and the high quality outer layer material. CONSTITUTION:A consumable electrode composed of the outer layer material 7 is inserted into gap formed between the core material 8 and the mold 2 concentrically set with the core material. While synchronously rotating the core material 8 and the mold 2 in the circular direction, the consumable electrode is melted by an electro-slag remelting(ESR) method in the slag bath, and in the rotation imparting ESR composite method forming the outer layer part 1 on the periphery of the core material 8 while melt-welding the outer layer material 7 with the core material 8, by using a pipe-shaped electrode in various manufacturing methods, the composite steel ingot is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite steel ingot by a rotation imparting ESR composite method mainly for producing a high performance composite roll for rolling.

[0002]

2. Description of the Related Art In order to meet the recent diversifying demands for performance improvement of rolling rolls, the limit of integrated rolls is reaching the limit, and development of high performance and high quality composite rolls is desired. .. That is, a rolling roll having a structure capable of imparting different performances to the body and the shaft has been required.

A method for manufacturing a composite roll is disclosed, for example, in Japanese Patent Publication No.
1-241307 gazette and other centrifugal casting composite method,
There is a method of surfacing by casting described in JP-B-2-35628, and a method of continuous surfacing using high frequency heating described in JP-B-44-4903. However, the centrifugal casting composite method is limited in the combination of the outer layer material and the inner layer material, and cannot be freely combined. Further, in the continuous build-up method using high frequency heating, the outer layer material cannot be made thick, and it is difficult to secure the usable diameter of the roll. In addition, the cast overlay method is a composite method that solves these problems and enables the production of high-performance rolling rolls, but the outer layer part that forms the body part is tempered as it is in the cast structure, so cleanliness, etc. There may be a problem in terms of quality, and it is difficult to apply it particularly to those requiring high quality rolls such as work rolls for cold rolling.

[0004]

As described above, in the conventional composite method, there is a problem in manufacturing a high-performance and high-quality rolling roll, and it is possible to freely combine the outer layer material and the core material (inner layer material) so that the boundary is formed. It is desired to have a composite method that has excellent joint properties and can be applied with a high quality material as the outer layer material.

[0005]

The compounding method disclosed in Japanese Patent Laid-Open No. 58-197232 is basically a compounding method capable of solving all of the above problems, and is for high-performance and high-quality rolling. It is the most suitable composite method for roll production. That is, while inserting the consumable electrode composed of the outer layer material component into the gap formed between the core material and the mold arranged concentrically with it, while rotating the core material and the mold synchronously in the circumferential direction, In the slag bath, the consumable electrode is melted by the electroslag remelting (ESR) method, and the outer layer material is formed around the core material while the outer layer material is welded to the core material. Since the materials are metallically welded and bonded, the bonding properties are excellent, and since the outer layer material is melted and built up by the ESR method, the quality of the outer layer material such as cleanliness is sufficiently high.

As the consumable electrode used in this rotation imparting ESR composite method, it is optimum to use a pipe-shaped electrode excellent in workability, yield, operability in ESR, etc., which is the gist of the present invention. .. The pipe-shaped electrode can be manufactured by a centrifugal casting method, a casting method using a sand mold or a die, a melting method, a continuous casting (CPC) method, a continuous casting method, or an integrated type. A method of hollowing out the inside of the round bar shaped material by machining etc. into a pipe shape, or a method of forming the powder of the outer layer material component into a pipe shape using a powder molding method such as HIP method, or extrusion, drawing, rolling , Plastic working methods such as forging are desirable.

[0007]

According to the present invention, the combination of the outer layer material and the core material is free, and it is possible to manufacture a composite steel ingot having an excellent joining property and a high quality outer layer portion.

[0008]

EXAMPLE As an example of the present invention, a pipe-shaped consumable electrode manufactured by hollowing out the inside of a round rod-shaped material manufactured by a centrifugal casting method and an integral type by machining etc. is used, and a rotation imparting ESR shown in FIG. 1 is used. A composite steel ingot was manufactured by the composite device.
Table 1 shows the approximate chemical components of the outer layer material and the core material at this time.

[0009]

[Table 1]

From this ingot, production and heat treatment were carried out to manufacture a work roll for cold rolling having a cylinder diameter of φ445 mm and a cylinder length of 1420 mm, and its quality was confirmed. The results are shown in Table 2 as a comparative table of the difference in the manufacturing results of the composite roll by the manufacturing method of the pipe-shaped consumable electrode.

[0011]

[Table 2]

It was confirmed that the quality was higher than that of the integrated roll manufactured by the same conventional ESR method, but the centrifugal casting method was overwhelming in terms of cost in comparison with the manufacturing method of the pipe-shaped electrode. , But cleanliness and ES
The R operability was slightly inferior. It was confirmed by various investigations that this is due to the shrinkage cavity-like unhealthy layer generated on the inner surface side of the pipe, which is unique to the centrifugal casting method.

As described above, each of the above-mentioned pipe-shaped electrode manufacturing methods has advantages and disadvantages, and can be effectively implemented by selecting the manufacturing method in consideration of the quality required for the product to be manufactured. Becomes

[0014]

EFFECTS OF THE INVENTION According to the present invention, since it is possible to manufacture a composite steel ingot having an excellent joining property and a high-quality outer layer portion, for example, a high-performance and high-quality work roll for cold rolling can be manufactured. It is possible to meet various needs for rolling rolls, such as achieving a drastic improvement in the roll unit consumption.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a rotation imparting ESR composite device manufactured according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pipe-shaped electrode for outer layer material, 2 ... Water cooling mold, 3 ... Molten slag, 4 ... Start plate, 5 ... Rotating platen, 6 ... Carbon brush, 7 ... Outer layer material, 8 ... Core material.

Claims (8)

[Claims] 1. A consumable electrode composed of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a pipe-shaped electrode manufactured by a centrifugal casting method is used as the consumable electrode, a method for manufacturing a composite steel ingot. 2. A consumable electrode made of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. A rotation imparting ESR in which the consumable electrode is melted by an electroslag remelting (ESR) method in a slag bath while rotating, and an outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the composite method, a pipe-shaped electrode manufactured by a casting method using a sand mold or a mold is used as the consumable electrode, and a method of manufacturing a composite steel ingot. 3. A consumable electrode composed of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a pipe-shaped electrode manufactured by a melting method is used for the consumable electrode, and a method for manufacturing a composite steel ingot. 4. A consumable electrode composed of an outer layer material component is inserted into a gap formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a pipe-shaped electrode manufactured by a continuous casting (CPC) method is used for the consumable electrode, a method for manufacturing a composite steel ingot. 5. A consumable electrode made of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a pipe-shaped electrode manufactured by a continuous casting method is used as the consumable electrode, and a method for manufacturing a composite steel ingot. 6. A consumable electrode composed of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a method for producing a composite steel ingot is characterized by using a consumable electrode in the form of a pipe by hollowing out the inside of an integrally manufactured round bar-shaped material by machining or the like. 7. A consumable electrode composed of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a method for producing a composite steel ingot, characterized in that a consumable electrode in which the powder of the outer layer material component is formed into a pipe shape by a powder molding method such as HIP method is used. 8. A consumable electrode composed of an outer layer material component is inserted into a space formed between a core material and a mold arranged concentrically with the core material, and the core material and the mold are synchronized in a circumferential direction. While rotating, the consumable electrode is melted by an electroslag remelting (ESR) method under a slag bath, and the outer layer portion is formed around the core material while the outer layer material is welded to the core material. In the ESR composite method, a pipe-shaped electrode manufactured by a plastic working method such as extrusion, drawing, rolling, and forging is used for the consumable electrode, and a method for manufacturing a composite steel ingot.