JPS60121029A - Manufacture of circular plate - Google Patents

Abstract

PURPOSE:To obtain an economical circular plate devoid of anisotropy qualitatively and dimensionally by rolling a flat circular plate obtained by forging and pressing an ingot of metal of spherical or columnar form etc. changing the direction of rolling successively. CONSTITUTION:An ingot S of metal cast to spherical form (or columnar form) is placed on an anvil 2 and worked by a press 1 to a flat circular plate 13. In this case, diameter D0 of the ingot S of metal is determined by a formula (alpha: yield rate, D: diameter of circular plate product, h: thickness of circular plate product). Then, the circular plate 13 is rolled by a press R in the direction of an arrow 12 rotating the circular plate 13 every one pass from the direction of rolling shown by an arrow 11 by an angle theta. Thus, a product of circular plate is obtained by repeating rolling changing the direction of rolling successively by rotating the circular plate 13 little by little.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a circular plate, and more specifically,
This invention relates to a method for manufacturing circular plate materials used for end plates of cylindrical tanks, spherical tanks, etc.

Typical examples of this type of circular plate material used in various tanks are shown in Figure 1, and these circular plate materials are shown in Figure 2 (
), a circular plate 3 is cut from a square plate, or a fan-shaped plate 5 is cut from a rectangular plate as shown in FIG.
It was produced by cutting and producing a lot of scrap, which was extremely uneconomical.

In addition, for square plates and rectangular plates, the rolling direction (L direction)
,) The direction perpendicular to the rolling direction (C direction) and the rolling direction and 4
Not only is there anisotropy in the material in the 5° direction (N) direction, but as shown in Figure 3, the thickness of the center part of the board (1-1c) is thicker than the end part of the board (He). It may have a crown, and it is very difficult to manufacture a circular root material, mirror plate, or hemispherical shell that is uniform in material and size from such a rectangular plate material.

In view of the various problems encountered in manufacturing conventional circular plates as explained above, the present inventor has conducted extensive research and has developed an economical circular plate that is free from anisotropy in terms of material and dimensions. Developed a manufacturing method.

The method for manufacturing a circular plate material according to the present invention is characterized by processing a spherical or cylindrical metal lump into a flat disk using a forging press, and then sequentially changing the rolling direction of the flat disk. The purpose is to perform rolling.

The method for manufacturing a circular plate according to the present invention will be described in detail below.

First, a case will be described in which a circular plate material is manufactured from a spherical metal lump.

A spherical mold 9 that can be divided as shown in FIGS. 4(a) and 4(b)
After pouring the molten metal M into the ladle 7, it is cooled and divided into divided molds 9.
The spherical metal ingot S is taken out by removing the footer pin 10 and opening the mold 9. In this case, the SJj manufacturing method may be a conventional method and there is no need to adopt a particularly limited casting method.

However, it is necessary to determine the diameter of the spherical metal lump depending on the size of the circular plate material to be manufactured. In this case, the diameter of the spherical metal lump is determined by the following formula.

D,,, = (L5/α・D2・h)'/3α:
Yield rate I): Product (disc) diameter 11: Product (disc) & thickness The spherical metal ingot S cast in this way is shown in Figure 5 (a).
As shown in (b), place the press 1 on the anvil 2''
Then, a flat disk 13 is obtained. Next, as shown in FIG. 6, this flat disk 13 is rolled to form a circular plate as a product. It is necessary to repeat rolling.Therefore, for each pass, the flat disk 13 is slightly rotated at an angle θ from the rolling direction in the direction of arrow 11, and rolling is performed in the direction of arrow ]2. 13 is rotated little by little to successively change the rolling direction and repeat the rolling.

Next, a case will be described in which a circular plate material is manufactured from a cylindrical metal lump.

In particular, when solidifying after remelting in electroslag remelting or vacuum arc 1[J melting, etc., unidirectional solidification progresses conveniently by casting into a cylindrical shape, and a healthy structure is obtained, so the cylindrical shape This is the preferred method for obtaining metal ingots. In addition, the vertical mold 9 shown in FIG. 7(a)(lj)
Molten metal 1111 is injected into a cylindrical metal block, and then a flat disk is formed using an anvil and a press.
According to the continuous casting method shown in the figure, after being injected into a drawing mold 15 from a tundish 14, it is lowered as a casting 16, cut 1117 to form a cylindrical metal ingot S, placed on an anvil 2'' and processed by a press 2. Then, a flat disk 13 is obtained. In this case, circular plates of various sizes can be manufactured from a raw material of one diameter by making the length of the cut slab that becomes the cylindrical metal ingot arbitrary.

The height of the cylindrical metal block is determined depending on the size of the circular plate 9 to be manufactured, and is determined by the following equation.

1+, = 1/α・D2/D, 2・II α: Yield coefficient 1): Product (disc) diameter Do: Material (cylindrical) Serious disease II: Product (disc) thickness in Figure 5 The heating method for heating the flat disc 13 when rolling the flat disc 13 by changing the rolling direction successively is shown, and the flat disc 13 cannot be stably placed on the skid width between the moving skid 21 and the fixed skid 22. Or, a flat disk 13 having a diameter smaller than the skid width.
is a plurality of flat discs] 3 are welded together by a joint plate 19 20
It is then joined together and placed in a heating furnace and heated.

Examples of the method for manufacturing a circular plate according to the present invention will be described.

Example C0113u+t%, Si 0.25wL%, Mn 1
．． 02u+L%, P O00]7u+1%, S O,0
After dissolving by electroslag + li dissolution method so that the content and component ratio is 14mL%, 800φX
A steel ingot of 12761+ was cast, and after heating at 1250°C x 1l (r), a 2000φ x 2
A flat disk of 001+ was manufactured. This flat disk is 120
f) 'CXO, after heating 51-1r, 4500 u+X
4 using a plate rolling mill with a work roll size of 10 inches) φ
(Monday) Rolled into a 0φX 501+ disc. Rolling is 2 (
011, finish in 6 passes to 50L, 6 for each pass
The disk was rolled by rotating it in the circumferential direction by 0°. As a result, the yield was 7i and J was completed! ri lj: 98.0% with any manufacturing method for circular plate material, but 70% and 65% with conventional method
(Steel plate manufacturing yield 90.0%, disk sampling yield 78.5%
), and it can be seen that the method for manufacturing a circular plate according to the present invention is extremely excellent. Regarding the uniformity of the abrasive quality, as shown in FIG. 10(b), according to the method for manufacturing a circular plate material according to the present invention, even if the rolling is different from the L direction and the C direction, the Charpy absorbed energy is Although there is not much change at each temperature, in the conventional method (L/C-8, 6) shown in Figure 1 (a) 1, the Charpy absorbed energy of the total heat is It can be seen that the circular plate 4 according to the present invention has excellent manufacturability.

As explained above, since the method for manufacturing circular plate materials according to the present invention has the above-mentioned configuration, the yield is better than the conventional method, and the quality is also disappointing. What is obtained from the circular plate is that its industrial value is very high.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing examples of various circular plate materials, Figures 2 and 3 are diagrams showing conventional manufacturing of circular plate materials and perspective views of rectangular plate materials, and Figures 1 and 7 are spherical metal plates. A schematic diagram showing the manufacturing method of ingots and cylindrical metal ingots. Figure 5 is a diagram showing the processing of a spherical metal ingot into a flat disk by pressing. Figure 6 is a diagram showing the case of rolling a flat disk by changing the rolling direction. Fig. 8 is an explanatory drawing of a case in which a cylindrical slab cast by continuous casting is cut and then processed into a flat disc by pressing, Fig. 9 is a diagram showing a method of heating a flat disc, Fig. FIG. 10 is a diagram showing the relationship between the Charpy absorbed energy and temperature of the circular plate 44 according to the method of manufacturing the circular plate according to the present invention and the conventional method. 1...Press, 2...Anvil, 9...Mold, 13...
Flat disc, S...Metal ingot, 8, T, 18 hot water, R...Rolling machine. (α) -80-60-40-20020 (0C) Spear 10 (b) -80-60-40-20020 (0C)

Claims (1)

[Claims] A method for manufacturing a circular plate I4, which comprises processing a metal lump of a spherical or cylindrical tube into a flat circular plate using a forging press, and then rolling the flat circular plate by sequentially changing the rolling direction of the flat circular plate.