JPH0261310B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for painting steel plates used in riverside or underwater construction, such as steel sheet piles for bank protection work and bridge construction work.

Conventional technology Steel sheet piles used for earth retaining during construction work underwater or along rivers had to be repainted with paint that can be used underwater when the paint peeled off during construction, but this method makes underwater work easier. As a means of painting steel sheet piles, a paint that hardens in water is applied in advance to one side of an anisotropic magnet on land, and the steel sheet pile and the magnet are brought into close contact with the painted surface interposed therebetween. Furthermore, copper foil was sometimes pasted on the magnetic surface that was in contact with water to prevent seaweed, aquatic plants, shells, etc. from adhering to it.

Problems to be Solved by the Invention In the conventional painting method as described above, the thicker the paint, the weaker the magnetic force becomes, and when no surface material is provided, algae and shells may adhere to the surface of the magnetic sheet by sinking into it. , it may damage the magnet surface and cause it to peel off along with the paint. In addition, if a copper foil is formed, the service life can be slightly extended, but it is completely prevented from peeling off due to the effects of tensile force caused by waves or other external forces, or due to deposits such as algae. Especially when copper foil was used underwater, it became brittle after about a year and needed to be repainted.

The present invention provides a coating method in which the paint can be stabilized by strong magnetic force and the paint and magnets will not peel off.

Means for Solving the Problems The method of the present invention involves fixing a ferrite stainless steel plate to one side of an anisotropic magnetic plate, applying a paint that hardens in water to the other side of the magnetic plate, and The paint side of the magnetic plate corresponds to the surface of the installed steel plate and is fixed tightly by magnetic force, which further enhances the magnetic properties (adsorption force, magnetic force) of the magnetic plate and also serves as a yoke. A ferrite stainless steel plate is used for this purpose, and a magnetic plate with a thickness of approximately 0.4 to 1 mm is
Fix a 20-100μ stainless steel plate and apply paint to a thickness of about 0.5-1mm.

Effect Since the present invention employs the above-mentioned coating method,
The ferrite stainless steel plate provided on the magnet surface can exert the yoke effect, and the
The magnetic force is about 50% stronger, and the coated magnetic plate can be strongly attracted to the iron plate.
Even when the steel plate has irregularities, such as where steel sheet piles are being constructed, compared to conventional methods, the stainless steel plate can be more easily aligned with the bends, and the steel plate surface can be completely covered with paint. Furthermore, it has approximately 2 to 4 times the hardness or durability against tensile force compared to surface agents such as copper foil, and almost no shells or algae stick to the stainless steel surface, preventing surface damage. can do.

EXAMPLE A case will be described in which a steel sheet pile construction site is painted by the method of the present invention.

1 is the earth retaining part, 2 is the steel sheet pile, and 3 is the underwater part. On land, a ferrite-based stainless steel plate 5, such as JIS standard number SUS430, is applied magnetically to the entire surface of one side of an anisotropic magnet sheet 4 made of soft synthetic resin that has been mixed with ferrite powder and magnetized with multiple poles. In close contact. Next, a paint 6 that hardens in water is applied to the other side of the magnetic sheet 4, and in a semi-dry state, the paint 6 is applied to the surface of the steel sheet pile 2 that is being constructed underwater for earth retaining. A magnet sheet 4 to which a stainless steel plate 5 is fixed is attracted to a steel sheet pile 2 by magnetic force so as to be in close contact with the steel sheet pile 2. The surface where a plurality of steel sheet piles 2 are connected has many bent parts, but the magnetic sheet 4 is flexible, and the stainless steel plate 5 can also be easily fitted along the bent parts, allowing the surface of the steel sheet piles 2 and the paint 6 to come into close contact even at the corners. Although the steel sheet piles are usually wider than the stainless steel plates 5, the joints of the stainless steel plates 5 are overlapped and welded. The stainless steel plate attached to the magnet sheet 4 has a function as a yoke, and the overlapped joint also has the effect of a yoke.

In this example, the thickness of the magnetic sheet is 0.8 mm.
The thickness of the stainless steel plate is 50 microns, and the thickness of the paint is 1 mm.
It is said that

Figure 3 shows another example, in which a release layer 7 was formed on the other side of a magnetic sheet 4 with a stainless steel plate fixed to one side, and then a paint 6 was applied, and the paint 6 was slightly hardened. Sometimes attached to submerged steel sheet piles by magnetic force. In the case of this embodiment, after the paint adheres to the steel sheet pile and hardens, the magnetic sheet can be peeled off at the part where the release layer 7 is formed. That is, the magnet sheet and the stainless steel plate can be used repeatedly.

Effects of the Invention Since the present invention employs the above-mentioned method, most of the painting work can be done on land, and only the pasting work is required underwater, and the pasting is done by magnetic force. Underwater work is easy, the underwater work time is short, and the work environment and work efficiency can be improved.

Furthermore, since it is the ferrite stainless steel plate that comes into contact with the water after painting, it has the effect of a yoke, and the strong magnetic force allows the coated magnetic plate to be brought into close contact with the iron plate. In addition, it has excellent strength and is not easily damaged by external forces such as waves, and has almost no adhesion of algae, shells, etc., so it can have a long life.

[Brief explanation of drawings]

Figure 1 is a sectional view showing the construction status of steel sheet piles, Figure 2
The figure is an enlarged sectional view of a coating state according to the method of the present invention, and FIG. 3 is an enlarged sectional view showing another embodiment.

Claims (1)

[Scope of Claims] 1. A ferrite stainless steel plate is fixed to one side of an anisotropic magnetic plate, and a paint that hardens in water is applied to the other side of the magnetic plate, and the painted surface of the anisotropic magnetic plate is A method of painting iron plates in which the sides and the surface of the installed iron plates are closely fixed by magnetic force. 2. The method for coating an iron plate according to claim 1, wherein a release layer is formed on the surface of the magnetic plate and then a paint is applied.