JPH0292408A - Horizontal roll for rolling h-shape steel - Google Patents

Abstract

PURPOSE:To prolong service life of a horizontal roll for H-shape steels by composing a sleeve of a central part having a hardened layer and of a pair of side parts having a hardened layer and connecting the side parts to both ends of the central part to be freely assembled and disassembled. CONSTITUTION:A horizontal roll for rolling H-shape steel is composed by mounting a sleeve 2 whose periphery is covered with a hardened layer 3 on a roll shaft 1 to be freely assembled and disassembled. Flanges and the web of an H-shape steel is rolled by the hardened layer 3. The sleeve 2 is composed of a central part 4 provided with a hardened layer 3a for web rolling and of a pair of side parts 5, 5 provided with a hardened layer 3b for flanges or web end rolling. The side parts 5, 5 are connected to both axial directional ends of the central part 4 to be freely assembled and disassembled. Thus, service life of the horizontal roll for H-shape steels is prolonged.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to rolls for rolling H-section steel, particularly horizontal rolls for universal mills.

(Prior Art) Generally, H-section steel is rolled using a universal mill as shown in FIG. This universal mill consists of a pair of upper and lower horizontal rolls 11.11 and a pair of left and right vertical rolls 1.
2.12, and the rolled material (H-shaped jli) is passed between these rolls and rolled and formed simultaneously from the height direction and width direction.

As the horizontal roll 11.11, a sleeve roll as shown in FIG. 3 is usually used. ! In the Pig Sleeve Roll, a sleeve 14 made of a high-carbon adamite material with excellent wear resistance is fixed to a roll shaft part 13 made of a tough material by a method such as shrink fitting.

During rolling of H-section steel, the following problems occur at various parts of the outer periphery of the sleeve 14. That is, the flange rolling part 1
In case 5a, particularly severe wear occurs because it rubs against the inner surface of the flange. Furthermore, the 8 part 15b for rolling the corner of the web and flange of the H-section steel has a high surface pressure during corner rolling, and the heat of the rolled material is likely to concentrate, resulting in heat cracks, rough skin, and seizure. do.

Therefore, it is inevitable that wear and roughness occur in these specific parts, so the outer peripheral surface of the sleeve is modified within the product dimensional tolerance determined by JIS and used again. The dimensional tolerance is, for example, a nominal dimension of 30
In the case of 0x300, the flange thickness is ±1.5 mm with respect to the specified dimensions, and the web thickness is ±1.0 m with respect to the specified dimensions, which are small values. Since the modification needs to be performed within such a small dimensional tolerance, the number of modifications is limited to about three. After the modification of a certain size H-beam within the specified tolerance,
In order to make a rolling roll of H-beam steel one size smaller than that size, the outer circumferential side of the sleeve is significantly cut to reduce the size and reuse it.

Incidentally, the JIS standard for product dimensions is defined in terms of external dimensions of 25 mm or 50 mm, so it is necessary to cut the outer peripheral side of the sleeve by about 25 to 50 mm when downsizing.

(Problem to be solved by the invention) However, in recent years, rolling conditions have become increasingly severe, and the sleeves of horizontal rolls for rolling H-section steel have improved wear resistance, seizure resistance, roughness resistance, etc. There is a demand for improved rolling properties and longer sleeve life.

In order to satisfy the above requirements, the outer circumference of the sleeve is made of a heat-resistant, high-hardness alloy material by hot isostatic pressing (hereinafter referred to as rHIp) treatment or plasma powder build-up welding (hereinafter referred to as rPPWJ) treatment. A hardened layer may be formed.

However, even when the above-mentioned hardened layer is formed, when used for a long period of time, local wear occurs in the rolled flange part and the R part, so it is necessary to modify the outer circumferential surface of the sleeve, that is, the hardened layer every about 1 m. In this case, as in the conventional example, due to dimensional tolerances, the sleeve for rolling H-section steel of the same size is 3.
It can only be revised and used once. On the other hand, if you want to reduce the size and use it, you have to make the initial hardened layer thicker in anticipation of the reduction in size. Most of the hardened layer must be removed. Moreover, there is a problem in that cutting of a hardened layer with high hardness is expensive.

The present invention was made in view of these problems, and
It is an object of the present invention to provide a horizontal roll for rolling H-beam steel that can effectively utilize the hardened layer having excellent rolling characteristics formed on the outer circumference of the sleeve.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a sleeve 2 having an H-section steel flange and a hardened layer 3 for web rolling formed on the outer periphery. A removably mounted horizontal roll for rolling H-section steel, the sleeve 2 having a central part 4 with a hardened layer part 3a for web rolling, and a hardened layer part 3b for rolling a flange or web end.
The structure of the invention is that the side parts 5.5 are connected to both ends of the central part 4 in the axial direction so that they can be disassembled and reassembled.

(Function) In the roll of the present invention, a sleeve 2 having an H-beam flange and a hardened layer for web rolling on the outer periphery is connected to the center portion 4 and the side portions 5, 5 so as to be disassembled and reassembled. It is composed of Therefore, the side hardened layer portion 3b corresponds to the flange rolling portion and the R portion.

Even after the modification to remove the wear and roughness occurring in the center part 3b is carried out within the dimensional tolerance, the center part 4 can be returned to within the predetermined tolerance by replacing it with a wider one. Therefore, it can be used as many times as a sleeve for rolling H-section steel of the same size as long as the hardened layer portions 3b, 3b of the side portions 5.5 can be modified.

In addition, even if you use a smaller size, you can reduce the size by simply replacing the center part 4 with a narrower one.
Significant removal of the hardened layer becomes unnecessary.

(Example) Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a horizontal roll for rolling H-section steel according to this embodiment, in which a sleeve 2 having a flange of H-section steel and a hardened layer 3 for web rolling formed on the outer periphery is attached to the roll axis l. It is attached removably.

A pressure medium injection chamber 6 is formed in the roll shaft 1 as a means for removably attaching it. When the pressure medium is injected into the injection chamber 6, the outer circumferential surface of the roll shaft 1 expands radially outward,
The sleeve 2 is fixed to the roll shaft 1.

The hardened layer 3 is formed by forming a hardened layer on the outer periphery of the sleeve 2 using a heat-resistant, high-hardness alloy powder such as SKD material or high-speed steel material and bonding it together by HIP treatment or PPW treatment. be.

The sleeve 2 includes a central part 4 having a hardened layer part 3a for web rolling, a flange or a web, that is, a corner part (R part) between the flange and the web, and a hardened layer part 3b for rolling the web end. a pair of sides 5 with 3b;
It consists of 5. The side parts 5, 5 are connected to both axial ends of the central part 4, and these three members can be disassembled and assembled using fixing means such as assembly bolts 7.

In the roll of this embodiment, the flanges of the side portions 5.5 or the corner hardened layer portions 3b, 3b for rolling are severely worn, and are used after being modified within the product dimensional tolerance.

Thereafter, before the dimensions of the product become out of tolerance, the sleeve 2 is removed from the roll shaft 1, the sleeve 2 is disassembled, and the central part 4 of the sleeve is replaced with a new one. The new center portion has a length in the axial direction that compensates for the dimension removed by the modification and the worn dimension. By assembling the side parts 5.5 in series with both axial ends of this new central part, the axial dimensions of the sleeve are restored to the original dimensions. After assembly, the side parts 5, 5 are modified and the outer circumferential surface of the central part is also refined so that it is flush with the surface. Then, it is mounted and fixed on the roll shaft 1 and used again for rolling an H-beam of the same size.

Although the web rolling section receives heat from the rolled material, it simply rolls down the rolled material, so severe wear and roughness do not occur as in the flange rolling section and R section (therefore, the web rolling section receives heat from the rolled material, so The hardened layer portion 3a for web rolling on the outer periphery of the portion 4 is
There is less wear and alterations can be kept to a small amount.

In addition, so that the width of the sleeve 2 after assembly is the inside dimension of the H-beam flange, which is one step below the product size standard, a narrow central portion is used, and the side portions 5. 5 are connected and fixed, and the side parts 5, 5 are modified and the outer periphery of the center part is machined flush, so that it can be reused as a sleeve for rolling an H-beam steel of a dimension standard below -. That is, it is possible to reduce the size of the sleeve without cutting a large part of the hardened layer.

When downsizing, the original center portion 4 may be processed to be narrower to adjust its dimensions and used as the narrower center portion.

The distance between the upper and lower sleeves, that is, the web rolling dimension of the H-shaped steel, is adjusted by moving the axis of the roll in the vertical direction.

In addition, the width of the sleeve after assembly is shown in the center part 4 of the sleeve.
It is also possible to increase the size of the sleeve by using a wide center part that has the inside flange dimensions of an H-beam steel whose product size standards are one step higher.

(Effects of the Invention) As described above, in the horizontal roll for rolling H-section steel of the present invention, the sleeve 2 provided with the descending layer 3 on the outer periphery is attached to the roll shaft 1.
The sleeve 2 is removably attached to the central portion 4.
and a pair of side parts 5, 5, which are connected to each other so that they can be disassembled and assembled.

Therefore, even if the hardened layer 3 is revised as it wears out and deviates from the tolerance range, the center portion 4 of the sleeve 2
By replacing it with a suitably wider one, it is possible to return to within the predetermined tolerance.

Therefore, the hardened layer parts 3b, 3b of the side parts 5, 5 can be modified as many times as necessary within the thickness range of the hardened layer, and the hardened layer formed on the outer circumference of the sleeve can be effectively used. . Therefore, the life of the sleeve for rolling H-section steel of the same size is significantly extended.

Furthermore, even when downsizing the sleeve 2, it is only necessary to replace the central part 4 with a narrower one and make normal modifications, and there is no need to remove a large amount of the hardened layer for downsizing. 1. There is little waste of the high-alloy material that forms the hardened layer, and cutting costs are extremely low.

Furthermore, by replacing the central portion 4 with a wider one, it is extremely easy to increase the size of the sleeve.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical cross-sectional view of a horizontal roll according to this embodiment, FIG. 2 is a front explanatory view showing a universal mill, and FIG. 3 is a partial vertical cross-sectional view of a conventional horizontal roll. 1... Roll shaft, 2... Sleeve, 3... Hardened layer, 3a... Hardened layer part for web rolling, 3b... Flange or hardened layer part for web rolling, 4... Center Part, 5
···side.

Claims (1)

[Claims] (1) Hardened layer for H-beam flange and web rolling (
3) is formed on the outer periphery of the sleeve (2), which is attached to the roll shaft (
1) is a horizontal roll for rolling H-beam steel removably attached to the sleeve (2), the sleeve (2) has a central part (4) having a hardened layer part (3a) for web rolling, and a flange or a web end part for rolling. It consists of a pair of side parts (5), (5) equipped with a hardened layer part (3b), and the side parts (5) are provided at both axial ends of the central part (4).
5) A horizontal roll for H-shaped steel rolling, characterized in that the rolls of (5) are arranged in series so that they can be disassembled and assembled.