JPH08281332A - Bevel disk roller of hot rolled steel sheet coiling machine - Google Patents

Abstract

PURPOSE: To improve wear resistance of bevel disk roller by joining the cobalt powder containing a specific quantity of niobium carbide on the sliding part of disk roller with which rolled steel sheet is in sliding contact, by plasma welding. CONSTITUTION: In a hot rolled steel sheet coiling machine, a sliding face 4', in which the powder consisting of cobalt containing 18-45wt.% niobium carbide with inevitable impurities is joined on the sliding part of a bevel disk roller 1 with which a rolled steel sheet is in sliding contact, is formed by plasma welding. At this time, a cobalt matrix which is not oxidized at about 500 deg.C and sufficiently diluted is provided as a base cladding by welding part 6. By forming of the sliding face, high hardness neobium carbide particle is dispersed as a particle in stellite 21 of the cobalt base, thus, good effect against scratching wear is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an umbrella-shaped disc roller for hot rolling steel sheet winding equipment having excellent wear resistance.

[0002]

2. Description of the Related Art A side guide with an umbrella-shaped disc roller of a general hot rolling steel sheet winding facility will be described with reference to FIG.
A pair of opposing umbrella-shaped disc rollers 1 are installed on the side guides 5, the side guides 5 are moved in opposition in accordance with the width of the rolled steel plate 3, and the pair of sliding surfaces 4 are brought into contact with both ends of the rolled steel plate 3. The rolled steel plate 3 is forcibly controlled by being guided and driven or driven to rotate.

However, since the sliding surface 4 of the disc roller 1 is in contact with the rolled steel plate 3, it is worn away due to scratching, sliding and the like. Therefore, the disk roller 1 is usually made of carbon steel material, and only the sliding surface 4 is formed by overlay welding with the wear resistant material 2 having wear resistance.

This wear resistant material 2 is a high carbon / high alloy system based on Fe and contains Cr, V, W and Nb, and these extremely hard carbides are melted and dispersed in the base.

Further, as described in Japanese Patent Application Laid-Open No. 1-289506, a side guide composed of a sliding member made of ductile cast iron having a specified component composition has been proposed.

[0006]

DISCLOSURE OF THE INVENTION Disc roller 1
As described above, the sliding surface 4 comes into contact with the rolled steel plate 3, scratches, slides and wears. Therefore, the thickness of the wear resistant material 2 is
The use limit is 5 mm in order to forcibly suppress the meandering of the rolled steel plate 3. When overlay welding is performed using a material whose hardness is simply increased for the wear resistant material 2, cracks and fractures occur in the residual stress of welding on the sliding surface 4 because the disk roller 1 has an umbrella shape. It will not be possible.

Therefore, in the umbrella-shaped disc roller of the hot-rolled steel sheet winding equipment, conventional overlay welding of wear-resistant materials causes rapid wear and frequent replacement, resulting in a problem of reduced work efficiency.

It is an object of the present invention to provide an umbrella-shaped disc roller for a hot-rolled steel sheet winding facility capable of improving wear resistance in order to solve the problem that work efficiency is reduced due to the short life as described above. It was done.

[0009]

In order to achieve the above object, the umbrella-shaped disc roller of the hot-rolled steel sheet winding equipment of the present invention has a sliding portion of the disc roller on which the rolled steel sheet makes contact and slides. It has a structure in which powders containing cobalt and unavoidable impurities containing at least 18 to 45% by weight of niobium carbide are joined by plasma welding.

[0010]

In the umbrella-shaped disc roller, it is necessary that the boundary layer between the disc-roller and the high-hardness welded portion joined by plasma welding is sufficiently diluted so that the disc-roller does not peel off when scratched.

Therefore, in the present invention, powder plasma welding was selected from the viewpoint of wear resistance and peeling resistance, in which welding work is effective and the components can be arbitrarily determined.

The wear-resistant umbrella-shaped disc roller of the present invention comprises:
Hard metal carbides are present in the cobalt matrix. That is, the wear-resistant umbrella-shaped disc roller of the present invention is
Hard niobium carbide is dispersed on the surface, and wear resistance is very excellent.

The weight ratio of niobium carbide to be dispersed is 4
If it exceeds 5%, cracks and fractures due to the residual stress of welding will occur, making it unusable.

The weight ratio of niobium carbide is 18%.
If the amount is less than the above, niobium carbide is melted by the heat during welding and dispersed in the cobalt matrix structure in a small amount, the amount of niobium carbide is small, and as shown in FIG. 3, sufficient wear resistance cannot be exhibited.

Further, instead of niobium carbide, other high hardness particles such as vanadium carbide and molybdenum carbide are melted by heat during welding and the shape of the particles becomes smaller than that of niobium carbide, resulting in wear resistance. I can't show enough.

The powder plasma welding according to the present invention is technically limited to the build-up of 3 mm, so that the wear resistance material is formed into a layer having a thickness of 5 mm, as shown in FIG. In addition, it is necessary to provide a layer sufficiently diluted with a cobalt base that does not oxidize at 500 ° C. as a layer of the lower overlay portion 6.

Therefore, on the sliding portion 4 of the disk roller 1 of the present invention, a powder of niobium carbide of 18 to 45% by weight and a balance of cobalt and inevitable impurities is added to the cobalt-based stellite # 21 by plasma welding. Join with.

[0018]

1 is a front view and a side view showing the structure of a disk roller body according to an embodiment of the present invention.

In FIG. 1, the same reference numerals as those in FIG. 2 have the same or the same functions. Reference numeral 6 denotes a lower build-up portion made of a cobalt base and 4'denotes a niobium carbide weight 18 to.
It is a sliding surface where a powder containing 45% of cobalt and unavoidable impurities is joined by plasma welding.

As a result, the high-hardness niobium carbide particles were dispersed as particles in the cobalt-based stellite # 21, and a sufficient effect on scratch wear was obtained.

FIG. 3 shows a niobium carbide weight ratio of 18-4.
It is the figure which compared the wear quantity of the 5% material, the wear quantity of the niobium carbide weight ratio 0-17% material, and the wear quantity of the Fe-based high carbon / high alloy wear resistant material. As is clear from FIG. 3, the wear amount 7 of the niobium carbide weight ratio material of 18 to 45% provided on the sliding surface of the present invention is equal to the wear amount 8 of the niobium carbide weight ratio of 0 to 17% material and Fe-based high carbon
It can be seen that the wear amount is much lower than the wear amount 9 of the high alloy wear resistant material.

[0022]

As described above, powder containing cobalt and unavoidable impurities containing at least 18 to 45% by weight of niobium carbide is contained in the sliding portion of the disk roller on which the rolled steel sheet of the present invention makes contact and slides. The umbrella-shaped disc roller of the hot rolling steel plate winding equipment joined by plasma welding is
Compared to an umbrella-shaped disc roller having a sliding surface made of a niobium carbide weight ratio material of 0 to 17% or a Fe-based high carbon / high alloy type wear material, the wear amount is small and the wear resistance is improved. Also, the work efficiency is improved and it can withstand long-term use.

[Brief description of drawings]

FIG. 1 is a front view and a side view showing a configuration of a disk roller body that is an embodiment of the present invention.

FIG. 2 is a front view showing the operation of a disc roller.

FIG. 3 compares the amount of wear of a material having a niobium carbide weight ratio of 18 to 45%, the amount of wear of a niobium carbide weight ratio of 0 to 17%, and the amount of wear of a Fe-based high carbon / high alloy wear resistant material. It is a figure.

[Explanation of symbols]

 1 Disc Roller 2 Wear-Resistant Material 3 Rolled Steel Plate 4, 4'Sliding Surface 5 Side Guide Body 6 Lower Overlay Part 7 Niobium Carbide Weight Ratio 18-45% Wear Amount of Material 8 Niobium Carbide Weight Ratio 0-17% Material Wear amount of 9 Fe wear amount of high carbon / high alloy wear resistant material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tamatoru Sato, 6-7 Minato-cho, Moji-ku, Kitakyushu-shi, Fukuoka Sankyu Co., Ltd. (72) Toshiyuki Katayama 1-3-8 Yaesu, Chuo-ku, Tokyo Nittetsu Hard Co., Ltd.

Claims (1)

[Claims] 1. A powder consisting of cobalt and unavoidable impurities containing at least 18 to 45% by weight of niobium carbide in a sliding portion of a disk roller on which a rolled steel sheet is brought into contact and sliding is joined by plasma welding. Umbrella-shaped disc roller for hot rolling steel plate winding equipment.