JPS6116123Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a low-cost stainless clad steel plate.

A conventional stainless clad steel plate is a plate as shown in FIG. 1A, FIG. A constant wall thickness (usually 3
The stainless steel parts 2 with a diameter of 2 mm or more are joined by a build-up method, an explosion bonding method, a rolling method, etc., and are made into a clad shape.

However, these stainless clad steel plates are
As shown below, due to the deterioration of the corrosion resistance of the welded part during welding, the thickness of the stainless steel part 2 cannot be made thin (to about 1 mm), resulting in an increase in cost.

That is, as shown in Fig. 2, the stainless steel part 2
The wall thickness is thinner (1 mm or more) than the conventional one (3 mm or more).
mm) When butt welding stainless clad steel plates, since the wall thickness of the stainless steel part 2 is thin,
The penetration of the base material carbon steel 1 during welding affects the surface of the stainless steel molten metal part 3, and the intergranular corrosion resistance of the stainless steel molten metal part 3 decreases due to the increase in carbon content. For this reason, conventional stainless steel clad steel plates usually have to have stainless steel parts with a wall thickness of 3 mm or more.

This invention reduces the cost of stainless clad steel sheets by making the wall thickness of the stainless steel parts as thin as possible without sacrificing the corrosion resistance that is a feature of stainless steel clad steel sheets. The present invention provides a stainless clad steel plate that can be maintained at the same level as the steel plate.

In other words, the present invention is designed to replace the majority of stainless clad steel plates used in large chemical reaction vessels, chemical tanks, etc., which are currently used without being cut and directly welded into plates in their manufactured state as shown in Figure 1A. Based on the fact that welding is often limited to the edges of stainless clad steel plates, welding is done at the joint edges of the carbon steel plates (up to about 100 mm from the edges). Only the part) has the normal thickness (3 mm or more),
This invention relates to a stainless clad steel plate characterized in that other parts are thinner (approximately 3 to 1 mm).

3A, B, and C are views showing one embodiment of the stainless clad steel plate of the present invention, in which FIG. 3A is a perspective view, and FIG. 3B is a longitudinal cross-sectional side view of FIG. 3C is a cross-sectional side view of FIG. 3A in the direction of the - line arrow.

In FIGS. 3A to 3C, the end of the stainless steel part 12 clad to the base material carbon steel plate 11 (100 meters from the end) is shown.
The wall thickness of 12A is the same as the stainless steel part of conventional stainless clad steel plate.
mm or more (here, 3 mm), and the wall thickness of the other portion 12B is approximately 3 to 1 mm (here, the minimum thickness that does not cause problems in corrosion resistance is 1 mm). On the other hand, the base material carbon steel plate 11 is
The end portion 11A is notched as shown in the figure to make it thinner than the other portion 11B.

The reason why the end portion is set to about 100 mm from the end is to sufficiently cover the weld bead portion even if the end portion is cut to some extent for beveling or alignment.

FIG. 4 is a sectional view of the vicinity of the welded portion, illustrating a state in which the stainless clad steel plates of the present invention shown in FIGS. 3A to 3C are butt welded.

In FIG. 4, the wall thickness of the stainless steel part 12 of the stainless clad steel plate is the same as that of the stainless steel molten metal part 13.
The thickness of the area 12A from the center to 100 mm on both sides is 3 mm, which is the same as the stainless steel part of the conventional stainless steel plate, and the other area 12B is 1 mm.

When the chemical composition of the stainless steel molten metal part 13 shown in FIG. 4 was investigated, the carbon content was 0.03wt%, and the carbon content of the stainless steel molten metal part 3 in the conventional butt welding of stainless steel clad steel plates shown in FIG.
There was no change at 0.031wt%. Therefore, it is considered that the corrosion resistance of the welded portion of the stainless clad steel plate of the present invention is equivalent to that of the conventional one.

Furthermore, in the case of the stainless clad steel plate shown in Fig. 4, the amount of stainless steel used can be reduced by about 60% compared to conventional ones, so the overall cost including processing costs can be reduced by about 10%.
In addition, when manufacturing using the overlay method, the number of man-hours can be significantly reduced, resulting in a cost reduction of about 30%.

As explained above, the stainless steel clad steel sheet of the present invention has corrosion resistance equivalent to that of conventional steel sheets, and can significantly reduce costs, making it extremely useful industrially.

[Brief explanation of the drawing]

Figures 1A to 1C are diagrams for explaining conventional stainless clad steel plates, with Figure 1A being a perspective view and Figure 1A being a perspective view;
Figure B is a longitudinal cross-sectional side view of Figure 1A in the direction of the - line
Figure C is a cross-sectional side view of Figure 1A in the direction of the arrow -2.
The figure is a sectional view of the vicinity of the welded part to explain the state in which the conventional stainless steel clad steel sheets shown in FIG. Figure 3A is a perspective view, Figure 3B is a vertical cross-sectional side view of Figure 3A taken along the - line, and Figure 3C is a cross-sectional side view of Figure 3A taken along the - line. FIG. 4 is a cross-sectional view of the vicinity of the welded portion, illustrating a state in which the stainless clad steel plates of the present invention shown in FIG. 3 are butt welded.

Claims (1)

[Scope of utility model registration request] In a stainless clad steel plate in which stainless steel is clad to a carbon steel plate and the carbon steel plate at the welded end surface is exposed, the thickness of the stainless steel part at the joint end of the clad plate shall be the same as the thickness of the stainless steel part in a normal stainless steel clad steel plate. , a stainless steel clad steel plate characterized in that the thickness of the stainless steel part in other parts is thinner than that.