JPH0929303A - Manufacture of flat plate having arc-shaped side face - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a flat plate at a low cost by hot-rolling a base stock by a specified method without using caliber rolls having grooves to manufacture the flat plate having arc-shaped side faces by hot-rolling. SOLUTION: The flat steel plate (a plate having round side) whose side faces have the arc shapes is manufactured by applying hot rolling such as the draft per pass is 25-50% at least once to a base stock (formed square) having thickness that a draft of >=65% is executed to the thickness of a product and its width becomes the width of the product by spreading caused by rolling with flat rolls. The thickness of an intermediate rolled stock is taken as thickness at which the draft of >=65% is ensured to the product thickness, because the radius of the side face of the round-side plate is insufficient when the draft is smaller than 65%. The draft per pass is taken as 25-50%, because the radius of the round side face of the round-side plate is insufficient when the draft per pass is smaller than 25% and the rolled stock is buckled when it is over 50%.

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 flat plate having arcuate side faces by hot rolling.

[0002]

2. Description of the Related Art A flat plate having an arc-shaped side surface (hereinafter referred to as "round edge plate") is used as a material for a screen used for a water intake of a power plant. This round edge plate is
It has the shape shown in Fig.
(Hereinafter, referred to as "edge R") is usually about 1/2 of H, but edge R does not have a strict standard, and ones larger than 1/2 of H are also used. Conventionally, this round edge plate has been manufactured by rolling using a hole-shaped caliber roll as shown in FIG.

[0003]

However, in the above-mentioned conventional method using the hole-shaped caliber rolls, it is necessary to manufacture the hole-shaped caliber rolls even when the production amount is small, and the product size is small. Even if it changed, there was a drawback that a new caliber roll had to be manufactured. An object of the present invention is to provide a method for producing a round edge plate without using a hole-shaped caliber roll.

[0004]

In order to achieve the above object, in the method for producing a flat plate (round edge plate) having arcuate side faces according to the present invention, a thickness capable of being rolled by 65% or more by the product thickness. Now, use a flat roll to roll a material with a width that will become the product width by rolling the width (hereinafter referred to as "modeling angle") with a flat roll.
Hot rolling is performed at least once such that the rolling reduction of each pass is 25 to 50%.

In the method of manufacturing the round edge plate of the present invention, the width of the shaping angle may be obtained by experience or by the formula of Shinokura et al. ΔB / BO = K × LDM / (BO + 0.5HO) × FH
/ FO FO: Inlet side area FH: Excluded area LDM: √R (HO
-H1) R: Roll radius HO: Sheet thickness before rolling H1: Sheet thickness after rolling BO: Sheet width before rolling B1: Sheet width after rolling (see FIG. 4) K in this equation is already known. The values (CC material (continuously cast material): 0.441, F material (forged material): 0.554) may be used as a reference for the estimation, or the material used to manufacture the round edge plate may be tested and tested. You can also ask for

As for the shaping angle used in the method for manufacturing the round edge plate of the present invention, a ready-made product having a desired size may be used, or if a ready-made product having a desired size cannot be obtained, It may be manufactured by hot rolling or the like. In the method of manufacturing a round edge plate of the present invention, the thickness of the intermediate rolled material is set to a thickness that can ensure 65% or more by the product thickness. ) Is insufficient. In addition, the rolling reduction of one pass is 25 to 50%.
The reason for this is that if the rolling reduction of one pass is less than 25%, the edge R of the round edge plate (see FIG. 2) becomes insufficient, and if it exceeds 50%, the rolled material buckles. Is.
Further, the rolling temperature is a normal hot rolling temperature, for example, S
In the case of US304, it is 1200-1230 degreeC.

[0007]

In the present invention, the shaping angle of a predetermined size is not reduced in the width direction, but is reduced in the sheet thickness direction, that is, the rolling in only the sheet thickness direction is performed by 65% or more in total, and is reduced in at least one pass. By rolling so that the rate becomes 25% or more, it is possible to manufacture a round edge plate having arcuate edge R formed on the side surface.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. Example 1 C: 0.05, which is a component composition of SUS304 as a material
%, Si: 0.33%, Mn: 1.86%, P: 0.0
28%, S: 0.025%, Cu: 0.44%, Ni:
8.39%, Cr: 18.68%, Mo: 0.24%,
N: 0.08%, stainless steel 14 consisting of balance Fe
A 6 mm × 146 mm square bar was used. 122 pieces of this timber
A heating angle of 0 ° C. was used to manufacture a fabrication angle of 97 mm × 120 mm by the process shown in FIG. 1 (a) using a flat roll and the fabrication angle molding pass schedule shown in Table 1.

The arrow in Table 1 indicates that the square bar is turned. For example, H: 117 obtained in pass 1
mm, B: (157) mm square bar was turned in the process of pass 2 to make H: (157) mm: B: 117, and this was rolled to obtain a H: 139 mm: B: (122) mm square bar. It shows that. In addition, the B value () in this table is
It shows the assumed value of the width dimension obtained by width expansion by rolling. Since it is difficult to measure accurately during rolling at high temperature, the value is assumed. (Below margin)

[0010]

[Table 1]

The molding angles formed in Table 1 are 30.33 mm in thickness, 151.degree. In width in the steps shown in FIG. 1 (b) and the round edge forming pass schedule of 4 times shown in Table 2.
A flat edge plate having a size of 26 mm and an edge R of 20.5 mm was manufactured.
The rolling reduction of the entire round edge molding pass was 68.7%.
The B value in parentheses () in Table 2 is an assumed value as in Table 1.

[0012]

[Table 2]

Target dimensions are a thickness of 30 mm and a width of 150 m
Since m and edge R were 20 mm, the thickness, width and edge R were slightly large, but there was no problem in using.

In the above embodiment, the flat roll is used to manufacture the shaping angle. However, when the corner caliber roll is used, the width dimension of the shaping angle does not vary and a stable dimension can be obtained. The caliber roll for corner can be used instead of the roll.

[0015]

EFFECTS OF THE INVENTION According to the present invention, since the flat plate (circular edge plate) having the arcuate side surface can be manufactured without using the hole-shaped caliber roll, the round edge plate can be manufactured at low cost. It has an excellent effect that it can be manufactured.

[Brief description of drawings]

FIG. 1 is a process drawing for explaining a method for manufacturing a round edge plate of the present invention.

FIG. 2 is a cross-sectional view of a round edge plate manufactured by the manufacturing method of the present invention.

FIG. 3 is a schematic view of a hole-shaped caliber roll used in a conventional method for manufacturing a round edge plate.

FIG. 4 is an explanatory diagram for explaining the equation of Shinokura et al., Which can be referred to for determining the width of the modeling angle.

FIG. 5 is a graph for explaining the K value of the expression of Shinokura et al.

Claims (1)

[Claims] 1. A material having a thickness capable of being rolled to a product thickness of 65% or more and having a width which becomes a product width by width expansion by rolling has a rolling reduction of 25 to 50% in one pass by a flat roll. A method for manufacturing a flat plate having arc-shaped side surfaces, characterized in that hot rolling as described above is performed at least once.