JPS6046889A - Production of multi-layered roll - Google Patents

Abstract

PURPOSE:To improve heat conduction between a roll shaft and the sleeves fitted to the outside circumference in the core part of the roll shaft and to avert dislodging and damage of the sleeves by subjecting said sleeves to an adequate pretreatment then to a hot isotropic pressing treatment. CONSTITUTION:For example, inside and outside sleeves 2, 3 are fitted to a core part 1 of a roll shaft. Both ends of the multi-layered roll are sealed 4 by electron beam welding and the entire part of the roll is encased externally with a hermetic outside body formed of a metallic light plate, etc. The parts exposed to the outside among the contact parts between the shaft core part and the sleeves or between the sleeves are sealed. Both ends of the roll are sealed 4 by electron beam welding in the case of the latter. The space part existing in the outside body or in the seal is evacuated and the roll is subjected to hot isotropic pressing treatment. The sleeves as well as the sleeves and the shaft core part are thus joined to one body and the purpose is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a roll in which a preferable material is arranged in each of the core portion, intermediate portion, and surface layer portion.

Rolls used for rolling, drawing, or conveying metal pieces are required to have wear resistance, corrosion resistance, oxidation resistance, and other various properties on the surface depending on the conditions of use. In many cases, properties such as sufficient rigidity and the ability to prevent the propagation of cracks are required for the parts and intermediate parts.

In this way, single rolls such as casting rolls are disadvantageous as rolls that require different properties on the roll surface and inside, and generally sleeve rolls with the required properties on the roll shaft and sleeve are used for this purpose. It is used.

Although it is possible to manufacture a roll having desired properties on the surface and inside of the roll using this sleeve roll, many drawbacks remain in the sleeve roll.

An example of this is as follows: (,) If the sleeve is not thick enough in applications where the roll is subjected to a large load, such as a rolling roll or a drawing roll, peeling will easily occur due to the propagation of cracks. Therefore, the thickness of the sleeve must be increased, but if the material of the sleeve is expensive, the roll cost will increase. It is originally impossible to reduce the thickness of the sleeve in a sleeve roll.

(b) In the case of hot rolls, for example sleeve rolls where the roll is heated to a high temperature and then cooled, such as a roll for continuous casting, there is insufficient heat conduction between the roll axis and the sleeve, so only the sleeve is at a high temperature. As a result of heating and cooling, the sleeve may expand and contract repeatedly or may fall off.

Also, thermal crack damage is significant.

(c) In the case of small rolls for shaped steel or shaping, there is a possibility that a sufficient shrink fit may not be possible.

etc.

The present invention aims to eliminate the above-mentioned drawbacks of sleeve rolls, and its gist is to fit single or multiple sleeves around the outer periphery of the roll axis, and to cover the entire sleeve with an airtight outer body made of a suitable material. In addition to encasing or sealing the parts exposed to the outside in the roll shaft core and the sleeve or the abutting parts of the sleeves, the space inside the outer body or the seal is evacuated, and then heat is applied. This is a method for manufacturing multiple rolls, characterized by applying isostatic pressure treatment between the rolls.

In addition, when the sleeve in the method of the present invention is used in double or triple layers, it is also possible to use a sleeve made of a powder-filled body except for the outermost layer. By doing so, it is easy to adjust the composition, and it is also easy to make a composite with, for example, a fibrous material mixed therein, and to increase its strength.

In addition, when using an airtight outer body as a preliminary treatment for hot isostatic pressure treatment, use a glass or metal thin plate, and when using a metal thin plate, if you choose a material that is appropriate for the material, it will not necessarily work after the treatment. It is also possible to create a finished product by leaving the outermost layer as it is without removing it.

Further, the preliminary treatment by the sealing method is advantageous if the electron beam welding method is adopted because the space can be made into a vacuum state at the same time.

The present invention will be described in detail below with reference to the drawings showing embodiments thereof.

The drawing shows a roll in which a double sleeve including an inner sleeve (2) and an outer sleeve (3) is present around the outer periphery of the roll axis (1). Both ends of such multiple rolls are sealed (4) by electron beam welding, and the entire roll is placed in a hot isostatic pressure furnace (not shown) filled with a suitable gas such as nitrogen or inert gas. By charging the inner and outer sleeves T211 and holding them under high temperature and high pressure.
At the interface (3) and the interface between the inner sleeve (2) and the roll axis 0), a roll metallurgically bonded integrally is obtained by diffusion bonding.

In such a roll, the sleeves and the sleeves and the roll shaft core are integrally connected, making it look like a sled or a trawl.
) and (C), sleeve rolls do not have any of the drawbacks, and since the material of each part of the roll can be changed in various ways, the above-mentioned drawbacks of solid rolls can also be eliminated.

For example, if the intermediate sleeve is made of a material with high toughness and high thermal conductivity, such as copper or copper alloy, the initial minute cracks and debris generated on the surface layer can be prevented from flowing into the inner part of the roll. In addition to being able to prevent the spread of heat, it is also possible to cool the entire roll through this intermediate layer with high thermal conductivity at the end of the roll, thereby extending the life of the roll.

Furthermore, in cases where copper or copper alloy is attached to the roll axis, or where the roll axis is made of aluminum, welding has extremely poor workability, but the hot isostatic pressure welding of the present invention can It has many advantages, such as being easy to carry out and being able to use powder or granules as the material.

In the case of materials that are difficult to form a metallurgical bond between the roll shaft core and the sleeves, or between each sleeve, a metallurgical bond promoting layer such as nickel may be interposed between them in the form of plating or powder particles. .

[Brief explanation of drawings]

The drawings are explanatory diagrams of one embodiment of the present invention. Patent applicant: Kuroki Industries Co., Ltd. Representative Haruyoshi Yukichi

Claims (1)

[Scope of Claims] 1. Fit a single or multiple sleeves around the outer periphery of the roll shaft core, and enclose the entire sleeve with an airtight outer body made of a suitable material, or fit the sleeve or sleeve to the roll shaft core. It is characterized by sealing the part exposed to the outside in the abutting part of the two, and making the space inside the extranuclear body or the seal into a vacuum state, and then applying hot isostatic pressure treatment. A method for manufacturing multiple rolls. 1. Claim 1, characterized in that the sleeve is double, the material of the inner sleeve is copper or copper alloy, and the material of the outer sleeve is a heat-resistant and wear-resistant alloy such as stainless steel. A method for manufacturing multiple rolls. 8. The method for manufacturing a multi-roll according to claim 2, wherein the inner sleeve is a powder-like material.