JPS5950406B2 - Partial composite rolling roll - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a composite roll in which the outer shell and inner shell, which correspond to the use layer, are made of different materials, and the outer and inner shells are integrally formed, in which the axial portion of the outer shell, which corresponds to the use layer, is made of different materials. The present invention relates to the provision of a new partially composite rolling roll suitable for applications requiring different properties.

In various types of rolling rolls, the use of composite rolls in which the inner shell (core material) is made of a strong material and the outer shell is made of a material suitable for the intended use is popular; for example, in the case of rolls for rolling long products, In order to perform different types of rolling with a set of rolls, a deep shape (
A hole with a shallow (small) shape may be provided on the opposite side, or a flat hole (with no hole) may be provided.
There are some rolls that have local differences, such as rolls that are rolled flat (flat).

In such rolls, the part with large holes rolls high-temperature steel materials and the reduction amount is large, so it is necessary to have particularly excellent crack resistance.On the other hand, the part with small holes or flat surface The temperature of the rolled material is low, and in order to obtain accurate texture and shape in the finished product, it is necessary to have particularly excellent wear resistance. Overall, the outer shell, which is the layer used, The properties such as hardness required differ depending on the axial portion.

However, when adopting a composite roll structure in which the outer and inner shells are made of different materials using centrifugal casting, etc., it is relatively easy to significantly change the properties of the outer shell and inner shell, which are the layers used on the roll surface. However, it is not easy to create large differences in properties in the axial direction of the outer shell in a composite roll made of different materials for the outer and inner shells, and it is desirable that the outer shell also be made of different materials in the axial direction. It will be done.

However, in cases where crack resistance and wear resistance are required partially in the axial direction of the outer shell, such as the above-mentioned long steel rolling rolls, the crack-resistant material generally has relatively strong toughness. If the outer shell, which requires crack resistance, is formed integrally with the inner shell using a crack-resistant material, it may be possible to provide the inner shell with sufficient toughness, and in this case, A part of the outer shell is made of the same material as the inner shell, and the other part is made of a wear-resistant material different from that of the inner shell, and each part has the required characteristics. This is the translation.

That is, in the present invention, for a composite roll such as the above-mentioned roll, which requires different properties in the axial direction of the outer shell, the outer shell and inner shell, which are used layers, are made different so that the requirements of each part can be satisfied. In a composite roll made of a material, only one or more parts in the axial direction corresponding to arbitrary parts of the outer shell are made of a material with a chemical composition different from that of the inner shell, while the rest of the axial direction of the outer shell and the inner shell are made of the same material. The object of the present invention is to provide a partially composite rolling roll which is integrally cast, and in which at least an outer shell portion and an inner shell formed of a material different from the inner shell are welded and integrated by casting.

The present invention will be described in detail below. First, the roll for rolling a long steel will be mentioned as a specific example of a preferred application of the present invention.

Therefore, to explain this case, for example, as shown in Fig. 1, the inner shell 1 (core material and neck part) and the outer shell 2 (
A part of the outer shell 2 in the axial direction a has a hole shape that requires crack resistance, and a part of the outer shell 2 has a flat part that requires wear resistance. In the present invention, as shown in FIG. 2, for a roll for rolling with multiple stripes, an inner shell 1 and an outer shell portion 4 corresponding to the axial portion a are provided.
The outer shell part 3, which corresponds to the axial part, is made of a material with high wear resistance and has a chemical composition different from that of the inner shell material. It is made of superior material and is welded and integrated with at least the inner shell 1 by casting.

An example of a manufacturing method for such a partial composite rolling roll will be explained with reference to FIG. 4. First, when manufacturing the required outer shell portion 3, the present invention uses a centrifugal casting method (horizontal type, vertical type, and inclined type). In addition, as a mold, a partition wall member such as an iron plate is erected in the circumferential direction on the inner surface, and the material change position is defined in the axial direction in advance.

That is, in FIG. 4, 5 is a centrifugal casting mold supported and rotated by a rotating roller 6, 7 is a partition member erected all around the circumference at a predetermined position in the outer shell casting cavity on the inner surface of the mold, and 8 is a mold. The sand mold section forming the roll neck casting cavity fixedly attached to the inner surface is shown.

In the mold 5 having the partition wall member 7 erected on its inner surface, the outer shell molten metal is partially poured into the mold inner surface defined by the partition wall member 7 through the gutter 9 inserted from the front end. The inner surface of the mold 5 is first coated with a material (in this case a wear-resistant material) of chemical composition having the required properties on the inner surface of the mold 5 in its axial direction 3'. Part of the shell is formed.

The mold 5, in which a part of the outer shell is partially formed on the inner surface of the mold defined in the axial direction by the partition member 7, is then further cast using a centrifugal force casting method or the mold 5 is placed upright. The remaining axial portions 4' of the inner and outer shells are formed by pour casting.
An inner shell molten metal having the required chemical composition (in this case, crack resistance and toughness) is cast, and the outer shell part 4 is integrally formed of the same material. The desired partially composite rolling roll is manufactured by welding the inner shell 1 and the outer shell portion 3 made of different materials together.

In this case, as in the case of manufacturing conventional composite rolls, it is sufficient to prepare two types of molten metal, and therefore there is an advantage that the roll can be manufactured economically.

Now, to explain the partition member 7, various methods can be devised to erect it on the inner surface of the mold, but one preferred method is to divide the mold 5 into outer sleeves 10 in the axial direction as shown in the figure. One example is a double structure in which the inner sleeve 11.11 is fitted inside, and the base of the partition member 7 is clamped and fixed between the divided inner sleeves 11.11.

According to this erecting means, the partition wall member 7 is
A stable upright state of the mold is ensured, and it is also convenient when dismantling the mold after composite roll casting.

Next, as the material for the partition wall member 7, a metal plate such as an iron plate can be used, and in this case, the thickness should be a certain degree (15 to 50 mm) so as not to be thermally deformed by the molten metal poured into both sides of the plate. It is preferable to have the following.

If a metal plate is used, it is desirable to weld it integrally with the outer shell portions 3.4 on both sides of the metal plate, and for this reason, the partition wall member 7 is provided with a surface for removing foreign matter such as rust. It is best to perform a cleaning treatment in advance.

However, even if the outer shell parts 3 and 4 are not welded together through the partition member 7, the outer shell part 3 will be completely welded to the inner shell by casting the molten metal in the inner shell, and this is practically impossible. There is no problem with rotation.

It goes without saying that the height of the partition wall member 7 should be determined more commercially than the thickness of the outer shell 3 to prevent the molten metal from flowing into the other side. .

In the above description, as an example, the outer shell is divided into two parts on both sides in the axial direction, and one part is made of a different material from the other part, but the present invention is of course applicable to this case. The present invention is not limited to this, but if the partitioning position of the inner surface of the mold is changed by erecting a plurality of partition members on the inner surface of the mold, for example, the axial center portion of the outer shell may be formed of a different material as shown in Fig. 3. Moreover, it is also possible to provide a structure in which multiple axial parts of the outer shell are made of a different material from the inner shell and other outer shell parts.In short, in the partial composite roll of the present invention, the outer shell axis One or more portions in the direction can be made of a material having a different chemical composition from the remaining portion formed integrally with the inner shell.

By the way, as a means to change the properties in the axial direction of the outer shell, it is possible to give different solidification cooling rates or different heat treatment methods to the outer shell made of the same material, or to partially change the machining allowance. Therefore, methods have been implemented in which the properties of the outer shell are partially changed in the axial direction, but these methods do not improve the performance compared to the manufacturing method of the partially composite roll of the present invention described above. The range of changes that can be made is extremely small.

A specific embodiment of the present invention will now be described.

<Example> In this example, a long steel rolling roll of 555φ x 15001 mm is required to have wear resistance up to 650 mm from one end of its body (outer shell), and crack resistance is required for the remaining part of the body. This is an example of application to a product. First, a part of the outer shell is made of the following adamite material to a thickness of 80 mm using the method shown in Figure 4.
After the outer shell was centrifugally cast and solidified, the mold 5 was stood upright, and the following adamite material was cast into the remaining parts of the inner shell and outer shell, and the two were welded together.

In this example, a steel plate with a thickness of 45 mm is used as the partition wall member 7.

According to the results of this example, a portion of the outer shell has a hardness of Hs5.
The hardness of the inner shell and the rest of the outer shell is Hs 44-49.
This resulted in a structure that was strong and highly resistant to cracking, and provided the necessary performance in each part.

As explained above, according to the partially composite rolling roll of the present invention, only a part or a plurality of parts in the axial direction of the outer shell are formed of a material having a chemical composition different from that of the inner shell, while the remaining part of the outer shell in the axial direction and The inner shell is integrally cast from the same material, and at least the outer shell and the inner shell, which are made of a different material from the inner shell, are welded together by casting. The parts can be formed of a desired material different from the inner shell material, and the outer shell can have properties similar to those required for the inner shell in the axial direction of the outer shell, as well as desired properties different from these. Moreover, since the outer shell parts made of different materials are welded and integrated, it is difficult to break even if the wall is thin or the hole shape is recessed, and a single product such as a roll for rolling long steel can be used for many purposes. If applied to rolls used for

[Brief explanation of drawings]

FIG. 1 is a sectional view of a rolling roll for long steel, FIGS. 2 and 3 are sectional views of a partial composite rolling roll according to the present invention, and FIG. 4 is an explanatory cross-sectional view showing the manufacturing method of the present invention. 1... Inner shell (core material), 2... Outer shell, 3
, 4... Outer shell portion, 5... Centrifugal casting mold, 7... Partition wall member.

Claims (1)

[Claims] 1. In a composite roll in which the outer shell and inner shell, which are used layers, are made of different materials, only a part or a plurality of parts in the axial direction corresponding to arbitrary parts of the outer shell are made of a material with a different chemical composition from the inner shell, and one The axial remainder of the outer shell and the inner shell are integrally cast from the same material.
A roll for partial composite rolling, characterized in that at least an outer shell portion and an inner shell formed of a material different from the inner shell are welded and integrated by casting.