JPH065083B2 - Anti-corrosion method for bolts and nuts and protective caps - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a bolt / nut anticorrosion method and a protective cap used therefor.

[Prior Art and Problems to be Solved by the Invention] Conventionally, when building various structures such as concrete structures and steel structures, it has been widely practiced to join members by using bolts and nuts. There is.

In particular, in the case of an outdoor structure, the bolts and nuts are exposed to the outside air, and if they are left as they are, there is a problem that corrosion progresses over a long period of time and the predetermined bonding force is lost. Therefore, conventionally, anti-corrosion coating is applied to the protrusions (exposed parts) for anti-corrosion of bolts and nuts.

However, since the bolts and nuts have complicated shapes, the coating work efficiency is not good, and the corner portions are apt to have a particularly thin film thickness, which deteriorates the anticorrosion performance. Furthermore, it is difficult to form a thick coating film by painting, and therefore corrosion protection over a long period of time cannot be expected.

Therefore, in order to give a thick anti-food material layer to the protruding parts of the bolts and nuts, prepare a protective cap with a shape corresponding to the protruding parts of the bolts and nuts, and fill the cap with the anti-food material.
A method has been proposed in which the cap is put on the bolt / nut projecting portion after being housed, the food-proof material is cured in this state, and the cap is attached as it is.

However, since conventional caps are made of metal such as aluminum and stainless steel and are opaque, even if a gap is created in the cap by covering the bolt / nut projection with the cap and filling the interior with the food-proof material, In some cases, it was not possible to form a good anti-food material layer.

Furthermore, in this method, since the cap is attached as it is, the weight of the conventional metal cap is relatively large, so that it will fall off after a long period of time due to contraction of the food protection material or vibration transmitted from the structure ( For example, in the case of railways, subways, and structures attached to roads, the vibration is remarkable, and the fall of the cap causes danger to traffic.

Therefore, a plastic cap such as polypropylene is also used in place of the metal cap, but when the cap is plastic, there is a problem that it is easily burned in a fire and is dangerous.

Therefore, in view of the above-mentioned problems of the prior art, the present invention does not burn at the time of fire, and has high work efficiency, the protective cap does not easily come off, and it is safe even if it falls, and a sufficiently thick anticorrosion coating is used. It is an object of the present invention to provide a corrosion preventive method for bolts and nuts that can be formed and does not cause a decrease in anticorrosion performance due to the formation of voids in the anticorrosion coating, and a protective cap used for the method for preventing corrosion of bolts and nuts.

[Means for Solving the Problems] According to the present invention, the above-described object is to provide a film-like film made of scale-like mica by forming a protrusion of a bolt and / or a nut connected to the structure from the structure. It is characterized in that it is covered with a protective cap made of glass fiber having a mesh structure with an internal see-through applied to the surface, and that the projection is covered by pre-filling the cap with an anti-food material. , The bolt / nut anticorrosion method.

Further, according to the present invention, the above-mentioned object is a glass fiber protective cap for covering a protruding portion of a bolt and / or a nut connected to a structure from the structure with a food material layer interposed therebetween. The protective cap has a network structure that allows internal see-through and is provided with a film-like film made of scaly mica on the surface.

[Examples] Specific examples of the present invention will be described below with reference to the drawings.

1 (a) and 1 (b) are schematic process diagrams showing an embodiment of the method of the present invention.

In these drawings, 2 is a bolt, 4 is a nut, and 6 and 8 are concrete plates which are structural members connected by these bolts and nuts. Reference numeral 10 denotes a washer which is arranged between the head of the bolt 2 and the concrete plate 6 in this connection, and 12 is a washer which is arranged between the nut 4 and the concrete plate 8 in the above connection. Reference numeral 14 is a protective cap for the bolt head side protrusion used for carrying out the method of the present invention, and 16 is a protective cap for the bolt / nut fitting side projection used for carrying out the method of the present invention.

The cap 14 is composed of a mesh structure, which will be described later, having a shape capable of covering the bolt head side protruding portion from the side portion and the upper portion at an appropriate interval (for example, at least 2 mm).
On the surface of the stitch structure, a film-like film 17 made of scale-like mica described below is applied.

In addition, the cap 16 has a bolt / nut fitting side protruding portion at an appropriate distance from the side portion and the lower portion (for example, a minimum of 2 m).
m) consisting of a mesh structure having a shape that can be covered. On the surface of the stitch structure, a film-like film 17 made of scale-like mica described below is applied.

First, as shown in FIG. 1 (a), the concrete plates 6 and 8 are joined by the bolt 2, the nut 4, and the washers 10 and 12, and the cap 14 for the bolt head side protrusion and the bolt / nut fitting side. A cap 16 for the protrusion is prepared.

It should be noted that the cap 14 and the cap 16 are preliminarily filled with the foodstuff 2
Fill with 2. It is desirable that the filling amount of the anti-corrosion material is a little larger than the filling amount of the hollow portion when the bolt and the nut are covered with the cap.

Next, as shown in FIG. 1B, the cap 14 is covered from above on the bolt head side projection, and the cap 16 is covered from below on the bolt / nut fitting side projection. In this state, it is left to naturally cure the anti-food material.

Since the caps 14 and 16 of the present invention have a stitch structure and the inside thereof can be seen through, the filling state of the anti-corrosion material can be visually checked, any residual voids can be checked, and appropriate measures can be taken.

As the anti-corrosion material 22, those conventionally used, for example, epoxy resin-amide type sealing agent, polyisocyanate-polyol type sealing agent, non-drying oil sealing agent and the like can be used. It should be noted that in order to prevent falling off due to external force such as vibration after curing and to make it flame-retardant, it is moderately flexible and has a relatively small specific gravity (for example, 1.4 or less) organic-inorganic Based or inorganic anticorrosive materials are preferred, and as such, the following formulations are suitable.

(1) (a) Acrylic emulsion resin and / or (b) Epoxy emulsion resin and polyamide resin or aliphatic polyamine curing agent: 5 to 50 parts by weight (solid content conversion), (2) Cement: 20 to 70 parts by weight, (3) hollow inorganic powder (average particle size 20 to 100 μm; for example, glass balloon, shirasu balloon, etc.) ... 5
40 parts by weight, and (4) fibrous material (for example, glass fiber having a length of 2 to 20 mm) ... 0.5 to 3 parts by weight, and if necessary, a rust preventive pigment, an extender pigment, and an additive. An anti-food material with a viscosity of 20 to 1000 poise, which is obtained by adding water to a mixture of the above.

Next, the protective cap of the present invention as described above will be described in more detail.

The protective cap is made of glass fiber to be non-flammable, durable, and transparent. Further, the protective cap has a mesh structure having a size such that the inside can be seen through. For example, the thickness of the protective cap is preferably about 0.1 to 3 mm, and the roughness of the mesh is preferably about 20 to 200 mesh. There is no limitation on the form of the mesh, and for example, FIG.
An example is shown in (c). 2 (a) is a plain weave net, FIG. 2 (b) is a twill weave net, and FIG. 2 (c) is a tatami weave net. Furthermore, a mesh non-woven fabric or the like can be used.

The protective cap of the present invention has an appropriate strength so as not to be deformed when the anti-food material is filled in the cap,
In addition, it is made of scaly mica that is non-flammable, and is colored or transparent to the extent that the inside can be seen through so that the solvent of the anti-food material does not stick out from the cap mesh, and that it is difficult to soften to obtain an effect such as blocking. A film-like film 17 is applied.

The film coating can be applied to the inside, the outside or both sides of the cap. In order to reduce the luster of the cap and prevent the operator from getting tired, it is desirable to apply it on the inside. A suitable thickness of the film-like coating is about 40 to 300 μm.

Next, a method for applying the film-like film will be described.

A flake mica powder having a diameter of about 0.1 to 2 mm and an aspect ratio of 100 or more, preferably 200 or more is dispersed in water to continuously produce a paper to form a film-like film of the mica, which is an inorganic adhesive. It can be applied by laminating and adhering it to a glass fiber cloth through. In this manner, the cap of the present invention is formed by using the glass fiber cloth coated with the film-like film made of scaly mica.

The scaly mica may be either natural mica or synthetic mica, but synthetic mica is preferable because it has better transparency, flexibility and heat resistance.

The synthetic mica is represented by the following general formula, for example.

X _{0.5 to 1} Y _{2 to 3} Z ₄ O ₁₀ F ₂ [where X is Na ⁺ , K ⁺ , Rb ⁺ , Ca ²⁺ , Ba]
²⁺ or Sr ²⁺ , Y is Mg ²⁺ , Fe ²⁺ , Ni
²⁺ , Mn ²⁺ , Al ³⁺ , Fe ³⁺ or Li ⁺ ,
Z is (Al ³⁺ , Si ⁴⁺ ), Si ⁴⁺ , Ge ⁴⁺ , A
l ³⁺ , Fe ³⁺ or B ³⁺ ] A particularly preferred synthetic mica is KMg ₃ (AlSi
₃ O ₁₀ ) F ₂ Fluoro phlogopite, KMg _2.5
Fluorine phlogopite represented by (Si ₄ O ₁₀ ) F ₂ , KMg
_{2.5 (Si} 4 _O 10) Fluorine potassium tetrasilic mica represented by _{F 2,} a teniolite represented by _{KMg 2.5 Li (Si 4 O 10} ) F 2.

Examples of the inorganic adhesive include silicate adhesives such as sodium silicate, potassium silicate, and lithium silicate, silica sol adhesives, alumina sol adhesives, and aluminum phosphates such as primary aluminum phosphates. Typical adhesives are aluminum-based adhesives, but aluminum phosphate-based adhesives composed of a first aluminum phosphate and a magnesium oxide curing agent are particularly excellent in terms of adhesiveness, transparency, flexibility and the like. Therefore, it is preferable.

By the method as described above, it is desirable to form a film-like film made of scale-like mica, because the overlapping of the mica becomes uniform and leakage from the protective cap of the food-proof material can be prevented.
It is also possible to form a film-like film by applying an inorganic coating material containing scaly mica. still,
In the case of an inorganic coating, it is desirable that the scale-like mica has a diameter of several tens of μm to several hundreds of μm.

[Effect of the Invention] According to the present invention as described above, since a protective cap made of a glass fiber having a mesh structure having a specific non-combustible coating on its surface is used, there is no risk of fire and the cap is It is light and easy to handle, has good workability, is hard to fall off, and has little risk if dropped. Further, since the inside of the protective cap can be seen through, the filling state of the anti-food material can be visually checked, and any residual voids can be checked.

[Brief description of drawings]

1 (a) and 1 (b) are schematic process diagrams showing an embodiment of the method of the present invention. 2 (a) to 2 (c) are views showing the mesh shape of the cap of the present invention. 2: Bolt, 4: Nut, 6, 8: Concrete plate, 10, 12: Washer, 14, 16: Protective cap, 17: Film-like film, 22: Anti-food material.

Claims (2)

[Claims] 1. A glass fiber protection having an internal see-through network structure in which a projection of a bolt and / or nut connected to a structure is provided with a film-like film made of scale-like mica on the surface. An anticorrosion method for bolts and nuts, which is characterized in that it is covered with a cap, and the protrusion is covered by preliminarily filling the cap with an anticorrosive material. 2. A glass fiber protective cap for covering a protruding portion of a bolt and / or a nut connected to a structure with a material-preventing layer, which has a mesh structure allowing internal see-through. A protective cap, characterized in that it has a film-like coating made of scaly mica on its surface.