JP2889131B2 - How to attach a metal sheet to the surface of a metal substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a corrosion-resistant and antifouling thin metal sheet formed of a metal substrate to prevent corrosion of metal structures such as marine structures, bridges, and various plants and to prevent adhesion of marine organisms. It relates to a method of attaching to a surface.

[0002]

2. Description of the Related Art Conventionally, anticorrosion and antifouling of the above-mentioned metal structure have been generally performed by applying an organic / inorganic paint. In this method, repainting is required in several years, so maintenance is complicated, and repainting is a dangerous operation. In recent years, corrosion-resistant and antifouling of metal structures installed in particularly severe places such as corrosive environments include metals with corrosion resistance and antifouling properties,
For example, a metal sheet coating method has been used in which a sheet of copper, copper alloy, stainless steel, titanium, monel, or the like (hereinafter, referred to as a metal sheet) alone or clad with ordinary steel is adhered to the surface of a metal substrate and coated. . This metal sheet coating method requires no maintenance and can be expected to have high anticorrosion properties and antifouling properties over a long period of time.

[0003]

The conventional metal sheet coating method has various methods, but has the following problems.

(1) A method in which a single metal sheet is stacked on a metal substrate and the outer periphery of the metal sheet is joined to the metal substrate by fillet welding. In this case, welding of dissimilar metals is difficult, and it is difficult to secure welding quality. In addition, it is necessary to increase welding heat input in order to sufficiently dissolve into a thick metal substrate.
In order to prevent the metal sheet from melting, the plate thickness had to be 1 mm or more. For this reason, the material cost becomes high, and the metal sheet becomes heavy, which is inconvenient to handle.

(2) A method in which clad steel is used as a metal sheet, and the ordinary steel portion of the clad steel is welded to a metal substrate (ordinary steel), and then the coated metals are welded to each other. Welding of the same kind of metal is possible and welding quality can be secured,
For the same reason as described above, the metal sheet could not be made thinner, and the production of clad steel, the high material cost, and the inconvenience of handling the metal sheet could not be eliminated. Even if these metal sheets are used alone or clad steel, the surface of the metal base material is changing in a curved shape,
When the metal sheet is fixed to a deformed structure, the metal sheet is thick, so that the rigidity is high, and the adhesion between the metal base material surface and the metal sheet deteriorates.

(3) Recently, a method has been proposed in which a metal sheet is adhered to the surface of a metal base material with only an adhesive or an adhesive to improve the performance of the adhesive or the adhesive. This method has the advantage that the thickness of the metal sheet can be reduced because there is no problem of melting by welding, but the adhesive or adhesive on the outer periphery of the metal sheet is exposed to light, outside air, water, etc. And the metal sheet peels off.

The inventors of the present invention have disclosed means for solving these problems as disclosed in Japanese Patent Application Nos. 5-339015 and 6-00.
No. 2597 proposes a method in which a metal sheet is attached to the surface of a metal substrate with an adhesive or an adhesive, and the outer peripheral portion is hermetically sealed by explosive bonding (FIG. 4). When these means are used, the material cost can be reduced, the outer peripheral portion and the wrap portion of the metal sheet can be securely hermetically sealed, and the maintenance-free anticorrosion and antifouling performance can be maintained for a long period of time.

An object of the present invention is to solve the above-mentioned problem mainly by using an easy-to-handle resistance welding method different from explosive joining.

[0009]

The gist of the present invention to achieve the above object is as follows. A metal sheet frame having corrosion resistance or antifouling property is fixed to the surface of the metal base material, the outer peripheral edge of a thin metal sheet of the same material as the metal sheet frame is placed on the metal sheet frame, and the overlapping portion is indirect resistance seam. A method of attaching a metal sheet to a surface of a metal substrate, wherein the metal sheet is joined and hermetically sealed by a welding method.

[0010]

The material of the metal sheet used in the present invention is, for example, titanium, monel, stainless steel or the like, which is a metal having excellent corrosion resistance in the case of anticorrosion, and has antifouling property in the case of antifouling. Select from excellent copper, copper-nickel alloy (cupronickel), etc. Since these metals are special metals, their material costs are high, and if they are thicker than necessary, they are disadvantageous in terms of material costs.

In the conventional method, when the metal sheet is fixed to the metal substrate as described above, the thickness of the metal sheet cannot be reduced from the viewpoint of weldability because fillet welding is performed.
m or more.

In the present invention, the metal sheet serving as the frame has a conventional thickness because it is joined to the metal base material by explosive joining or fillet welding. By using a thin metal sheet less than the material, the material cost can be reduced, and the handleability of the material can be improved.

Further, the outer peripheral edge of the thin metal sheet is fixed to the metal sheet frame fixed to the metal substrate by welding, and the other than the outer peripheral edge is fixed on the metal substrate with an adhesive or an adhesive. The number of fixing portions of the sheet to the metal base increases, and the sheet can be prevented from being lifted off, separated from the metal base, and the adhesion can be improved.

Further, the welding of the metal sheet frame and the thin metal sheet is performed by indirect resistance seam welding. However, the use of the metal sheet frame facilitates the construction and makes it easy to ensure the quality.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a means for attaching a metal sheet to the surface of a metal substrate according to the present invention. FIGS. 2 and 3 show a pier installed in the sea and a steel pipe in a tidal zone / splash zone of an offshore structure. FIG. 2 shows a state where a metal sheet frame is fixed to a steel pipe, and FIG. 3 shows a state where a thin metal sheet is pasted thereon to complete the construction.

The means for fixing the metal sheet frame 1 to the surface of the metal base material includes fillet welding and explosion welding according to the material of the metal sheet frame 1. In the case of stainless steel or clad steel (such as ordinary steel and titanium), the metal sheet can be directly welded and fixed to the metal substrate by fillet welding. In the case of titanium or the like which is difficult to be directly welded to a metal substrate, it is fixed by explosive joining. In the case of explosive joining, the metal base and the metal sheet frame are stacked so as to have a predetermined interval, explosives are set on the metal sheet via a buffer material such as an aluminum plate, and ignited and exploded using a primer. Thus, the metal sheet frame 1 is fixed to the surface of the metal substrate 5.

After the predetermined metal sheet frame has been fixed to the metal substrate (steel pipe), the outer peripheral end 3 of the thin metal sheet 2 is placed so as to overlap the metal sheet frame 1, and the overlapping portion is indirect resistance seam. Hermetically sealed by welding. The overlapping area 4 excluding the outer peripheral edge of the thin metal sheet 2
And the metal substrate 5 may be left as it is, but the overlapping area 4 excluding the outer peripheral edge of the thin metal sheet 2
Applying an adhesive or an adhesive 6 made of an acrylic, epoxy, butyl, polyethylene, or vinyl synthetic resin to the resin and attaching the adhesive resin 6 gives a better result in terms of impact resistance. In this way, the metal substrate 5 and the thin metal sheet 2 can be adhered over the entire surface, and the thin metal sheet 2 does not float up, and furthermore, there is no air containing moisture inside, so that it is more advantageous in terms of corrosion protection. Along with
There is an advantage that even if a part of the thin metal sheet 2 is scratched, it can be protected by the adhesive or the adhesive 6.

For indirect resistance seam welding of the outer peripheral end 3 of the thin metal sheet 2 onto the metal sheet frame 1, as shown in FIG. 1, one roller electrode 7 of a resistance welding machine having two roller electrodes is used. Is disposed on the overlapped portion of the metal sheet frame 1 and the thin metal sheet 2, and the other roller electrode 7 is moved in the welding direction while being in contact with the metal sheet frame 1 and energized. The welding conditions depend on the material and thickness of the metal sheet.
You need to choose an appropriate value.

The interval between the metal sheet frames 1 can be made equal to the width of one thin metal sheet of a prescribed size, or can be made wider by wrapping a plurality of thin metal sheets 2 together. In that case, before the thin metal sheet 2 is attached to the metal base material 5, the lap portion of the thin metal sheet 2 is joined in advance by resistance welding using the roller electrode 7 facing the thin metal sheet 2. Alternatively, a plurality of thin metal sheets 2 may be attached to the metal substrate 5 and then the lap portions of the thin metal sheets 2 may be joined by indirect seam welding using parallel roller electrodes 7.

The thin metal sheet 2 can be stuck on the metal substrate 5 using the metal sheet frame 1 in the above-described procedure.

[0021]

According to the present invention, a metal sheet serving as a frame is joined to the surface of a metal substrate by explosive joining or fillet welding, and a thin metal sheet is sealed thereon by resistance seam welding, which is easy to operate and ensures quality. This is a metal sheet coating method for sealing. Therefore, compared with the conventional metal sheet coating method in which the metal sheet is fillet welded over the entire area covered with the metal base material, a thin metal sheet can be used, thereby reducing the material cost of the metal sheet. In addition, the material handling properties can be improved. In addition, since the thin metal sheet is attached via the metal sheet frame fixed to the metal substrate, the adhesion to the metal substrate is improved, and the construction is facilitated.

In addition, since the outer peripheral edge of the metal sheet is hermetically sealed by resistance seam welding, the metal substrate is completely shielded from light, outside air, water and the like, and complete corrosion protection can be expected. Furthermore, when an adhesive or an adhesive is used for the overlapping portion other than the wrap portion and the end portion, the end portion can be completely shielded from light, outside air, water, etc., so that the adhesive and the adhesive do not deteriorate. It has the effect of maintaining corrosion- and antifouling performance without maintenance for a long time.

Further, it is also possible to use a metal such as titanium which cannot be welded due to generation of an intermetallic compound or the like in welding with general carbon steel.

[Brief description of the drawings]

FIG. 1 is an end sectional view showing an embodiment of attaching a metal sheet according to the present invention.

FIG. 2 is a view showing a state of fixing a metal sheet frame to a steel pipe according to the present invention.

FIG. 3 is a view showing a completed state of attaching a thin metal sheet to a steel pipe according to the present invention.

FIG. 4 is a view showing a conventional example (pasting of a thin metal sheet by explosive joining).

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 metal sheet frame 2 thin metal sheet 3 outer peripheral end 4 overlapping portion excluding outer peripheral end 5 metal base material 6 adhesive or adhesive 7 roller electrode 8 fillet welding 9 resistance welding 10 explosive joining 11 metal sheet A buffer material B Explosives

Claims (1)

(57) [Claims] 1. A metal sheet frame having corrosion resistance or antifouling property is fixed to a surface of a metal substrate, and an outer peripheral end of a thin metal sheet of the same material as the metal sheet frame is placed on the metal sheet frame.
A method of attaching a metal sheet to a surface of a metal substrate, wherein overlapping portions are joined and sealed by indirect resistance seam welding.