JP3294523B2 - Steel joining method and paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining steel members by a high-strength bolt friction joining method. To paint.

[0002]

2. Description of the Related Art Bridges and buildings are usually constructed by joining steel members by a high-strength bolt friction joining method, a rivet joining method, a welding method, or the like.
In addition, a high-strength bolt friction joining method is dominant because a joint having high rigidity can be obtained. In this high-strength bolt friction joining method, steel members a and a 'are tightened with high-strength bolts 1, nuts 2 and washers 3, 3' as shown in FIG. This is a joining method that transmits stress by frictional force. The friction coefficient of the high-strength bolt friction joint surface is required to be 0.40 or more for bridges and road bridges, and 0.45 or more for general buildings. By the way, a method of applying an inorganic zinc-rich paint using a binder such as an alkyl silicate hydrolysis condensate or the like to a joint surface of a steel member has been widely adopted in order to make the friction coefficient 0.40 or more.

That is, a method of applying an inorganic zinc-rich paint in advance on the entire surface including the joint surface of a steel member, joining the steel members, assembling, and then applying an anticorrosive paint on the entire surface for corrosion prevention. It was constructed in. However, since a coating film formed from an inorganic zinc-rich coating material is a porous film, a foaming phenomenon occurs when the anticorrosion coating is suddenly applied, and there is a problem that a smooth and normal coating film cannot be obtained. Therefore, conventionally, before applying the anticorrosive paint on the surface of the inorganic zinc-rich coating film, apply a paint diluted with a large amount of solvent called a mist coat to the inorganic zinc-rich coating film beforehand, plug the pores of the porous part, Thereafter, a normal anticorrosive paint was applied. Further, the inorganic zinc-rich paint has to be highly quenched on the surface of the steel member to remove rust as compared with the organic zinc-rich paint using an epoxy resin or the like as a binder. For this reason, the method of applying an inorganic zinc-rich paint has a problem in that the number of painting steps is increased as compared with the method of applying an organic zinc-rich paint, and a high-level keren step is required, resulting in poor painting efficiency.

Accordingly, a method of applying an organic zinc-rich paint using an organic synthetic resin as a binder which forms a smooth coating film without the need for a high-level keren or mist coat has been studied. The coating has a coefficient of friction of 0.
It is not more than 40, at most around 0.30, and therefore no organic zinc-rich paint has been used in the high-strength bolt friction joining method.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and utilizes the smoothness of an organic zinc-rich coating film and has a friction coefficient of 0.4.
An object of the present invention is to provide a paint for forming zero or more coating films and a method for joining steel materials to which the paint is applied.

[0006]

Means for Solving the Problems The present inventor has made intensive studies in order to achieve the above object, and as a result, has found that the following object can be attained by the following constitution, and has reached the present invention. That is, the present invention provides the following invention: a method of joining a steel member of the first invention by a high-strength bolt friction joining method, wherein at least a joining surface of the member is made of epoxy resin (A) and The weight mixing ratio of the binder (i) composed of the curing agent and the inorganic binder (ii) is (2
5:75) to (100: 0) with a binder of 5 to 20
(B) 50 to 90% by weight of zinc powder or zinc alloy powder having an average particle size of 1 to 30 μm and 50% or more having a particle size of 2 μm or more, and (C) a pigment (zinc powder, zinc alloy powder excluded) 1 to 40 wt%, and applying a coating material containing the bonding method of the steel material, characterized in that the coating film was allowed to form a dry film thickness of 30 to 150 [mu] m, and the second invention (a) an epoxy resin and Binder consisting of the curing agent (i)
And the weight ratio of the inorganic binder (ii) and (25: 7)
5) A binder consisting of 5 to 20% by weight (100: 0), (B) an average particle diameter of 1 to 30 μm, and 50% or more is 2%.
Zinc powder or zinc alloy powder having a particle size of at least μm 5
0 to 90% by weight and (C) 1 to 40% by weight of a pigment (excluding zinc powder and zinc alloy powder) as a coating film forming component are joined by a high strength bolt friction joining method. The present invention relates to a coating material for coating a joint surface of a steel member.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The paint applied to the joint surface of the steel member to be joined by the high-strength bolt friction joining method of the present invention is a binder (i) (A) composed of an epoxy resin and a curing agent thereof, or the binder (i) and an inorganic material. Mixed binder (A) with system binder (ii), zinc powder or zinc alloy powder (B), pigment (C), and any other modified resins, suspending agents, A film-forming component (that is, solid content) comprising various additives such as an agent and an antifoaming agent and a solvent. As the epoxy resin which is a component of the binder (A), various epoxy resins conventionally used in zinc-rich paints can be used without any particular limitation.

That is, flame-retardant epoxy resins such as epichlorohydrin-bisphenol A type epoxy resin, epichlorohydrin-bisphenol F type epoxy resin, glycidyl ether of tetrabromobisphenol A, novolak type epoxy resin, hydrogenated bifphenol A type epoxy resin Representative examples include glycidyl ether type epoxy resin of bisphenol A propylene oxide adduct, diaminodiphenylmethane type epoxy resin, urethane modified epoxy resin, hydantoin type epoxy resin, epoxidized polyolefin, epoxidized soybean oil, and various modified epoxy resins. It is listed as. Examples of the curing agent include aliphatic polyamines such as ethylenediamine and diethylenetriamine, modified aliphatic polyamines obtained by modifying aliphatic polyamines with bisphenol A and acrylonitrile, aromatic polyamines such as diaminodiphenylmethane, and fats such as N-aminoethylpiperazine. Cyclic polyamines, modified alicyclic polyamines obtained by modifying alicyclic polyamines with Cardura E, xylylenediamine, polyamides obtained by reacting polyamines with dimer acids, amine adducts obtained by adducting polyamines with epoxy resins, and polyamines obtained by dimer acid And a polyamide adduct adducted with an epoxy resin.

The binder (i) is composed of an epoxy resin and a curing agent thereof. The mixing ratio of the two is usually 0.5 to 3.0 equivalents, preferably 0.5 to 3.0 equivalents, per 1 equivalent of the former epoxy group. An appropriate ratio is 0.9 to 1.5 equivalents, and within this range, the original epoxy resin coating film performance is exhibited. In the present invention, the binder (A) may be the binder (i) alone,
It is also possible to use an inorganic binder (ii) in combination. The inorganic binder (ii) has a small degree of softening due to frictional heat, and therefore, when used in combination with the binder (i), has an effect of improving the friction coefficient. However, if the inorganic binder (ii) is excessively blended, it is necessary to highly vibrate the surface of the steel member and to prevent rust, or the obtained coating film becomes porous, and a mist coating is required. Absent. Therefore, the blending amount of the inorganic binder (ii) is 75% by weight in the binder (A).
Hereinafter, preferably 5 to 50% by weight is appropriate.

Examples of the inorganic binder (ii) include alkyl silicate hydrolyzed condensates or modified products thereof, and metal alkoxy compounds such as aluminum, titanium, zirconium and tin, which are usually used in inorganic zinc-rich paints. , A hydrolysis condensate thereof or a modified product thereof. Zinc powder or zinc alloy powder containing zinc as a main component, such as zinc-aluminum, zinc-magnesium (B),
In order that the coefficient of friction of the obtained coating film is 0.40 or more, the average particle size is 1 to 30 μm, preferably 3 to 15 μm.
m, and 50% or more is 2 μm or more, preferably 3 μm
The one having the above particle size is used. The average particle size is 1 μm
If it is less than 50% or zinc powder or zinc alloy powder having a particle size of 2 μm or more is less than 50%,
On the other hand, it is difficult to adjust the average particle diameter to 0.40 or more. On the other hand, if the average particle diameter exceeds 30 μm, the coating film becomes a porous film, which requires a mist coating, which is not preferable.

The pigment (C) is distributed between the zinc powder or the zinc alloy powder (B) in the obtained coating film, prevents the zinc powder or the zinc alloy powder (B) from moving due to friction, and reduces the friction coefficient. It is blended to prevent the drop. As the pigment (C), various coloring pigments, extender pigments, anticorrosion pigments and the like which are usually used for paints can be used without any particular limitation, but those which are harder than zinc powder (Mohs hardness 2.5) have a friction coefficient of Thus, a pigment having a Mohs hardness of 2.5 or more, particularly preferably 5.0 or more, is desirable. Pigments having a Mohs hardness of 2.5 or more include, for example, magnesium hydroxide, calcium carbonate, fluorite, phosphite, hydrous iron oxide, black iron oxide, titanium anatase oxide, rutile titanium oxide, silicon dioxide, alumina, carbonized Typical examples include silicon, aluminum powder, iron powder, stainless steel powder, and carbon.

Other oxide pigments such as chromium oxide, zirconium oxide and composite oxide; phosphates such as zinc phosphate and aluminum phosphate; phosphonates such as zinc etidronate, calcium etidronate and melamine etidronate; molybdenum Salt pigments such as molybdate, phosphomolybdate, vanadate, borate, chromate, plumbate, silicate such as zinc oxide, silicon nitride, glass beads, phosphorous iron powder, and other phthalocyanines, Heat-resistant organic pigments such as quinacridone are also typical examples. The average particle size of these pigments is suitably 30 μm or less, and if it is more than 30 μm, the coating film tends to be a porous film. Modified resins that are blended as needed as coating film forming components include xylene resins, petroleum resins, cumarone resins, ketone resins,
Phenol resins and the like can be mentioned. Solvents incorporated to dissolve or disperse these film forming components include aromatic hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone and cyclohexanone, ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate and the like. Representative examples include esters, alcohols such as isopropyl alcohol and butyl alcohol, and water.

The paint of the present invention is composed of the components described above.
(A) is 5 to 20% by weight, preferably 6 to 15% by weight, zinc powder or zinc alloy powder (B) is 50 to 90% by weight, preferably 60 to 85% by weight, and pigment (C) is 1 to 40% by weight. weight%,
Preferably, 5 to 30% by weight is appropriate. In addition, binder
If the amount of (A) is less than the above range, the physical and chemical properties of the original coating film will not be exhibited, and if the amount is large, the zinc powder or zinc alloy powder (B) and the pigment (C) will be relatively present. It is not preferable because the amount becomes small and it becomes difficult to obtain a coating film having a friction coefficient of 0.40 or more. When the amount of the zinc powder or the zinc alloy powder (B) is less than the above range, the anticorrosion property is reduced, and when the amount is too large, the amounts of the binder (A) and the pigment (C) are relatively small. It is not preferable because the properties of the coating film deteriorate. Also pigment
If the amount of (C) is less than the above range, it becomes difficult to obtain a coating film having a friction coefficient of 0.40 or more, and if it is too large, the zinc powder becomes relatively
It is not preferable because the amount of (B) decreases and the anticorrosion property decreases.

The mixing ratio of the solvent in the paint can be set to an arbitrary amount in consideration of the workability of coating and the like.
-30% by weight (i.e., 70-95% by weight of paint solids);
Preferably, the content is set to 10 to 20% by weight because a film thickness described later is easily obtained. Next, the method for joining steel members of the present invention will be described. The steel member referred to in the present invention is a steel member applied to various outdoor steel structures such as warehouses, private houses, small buildings such as stores, large buildings such as buildings, and even bridges, road bridges, tanks, and the like. is there. After the surfaces of these steel members before being joined by the high-strength bolt friction welding method are subjected to surface treatment such as rust removal, the above-described paint is applied to the entire surface of the steel members. The application location may be applied only to the joints of the steel members, but after joining and assembling the steel members, it is necessary to apply the same paint to places other than the joints, so before joining the steel members It is desirable to apply it to the entire surface including the joint.

As the applying means, for example, various conventionally known applying means such as spray coating and brush coating can be adopted. The dry film thickness of the obtained coating film is 30 to 150 μm
, Preferably 50 to 100 μm. If the film thickness is smaller than the above range, not only does the long-term corrosion protection deteriorate, but also the friction coefficient decreases. After the paint applied to the steel members is dried, the steel members are joined and assembled to construct various steel structures. The assembled steel member is finished by applying an anticorrosive paint such as a normal epoxy resin paint, a polyurethane resin paint, an alkyd resin paint, a chlorinated rubber paint, and a fluororesin paint. Especially for bridges and outdoor steel structures such as tanks, epoxy resin base coat paint → (polyurethane resin middle coat paint) → polyurethane resin top coat paint, epoxy resin base coat paint →
(Polyurethane resin-based intermediate paint coating) → It is desirable to apply a heavy-duty anticorrosive coating with a coating system such as fluororesin-based topcoat paint.

[0016]

The present invention will be described in more detail with reference to the following examples. In the examples, "parts" and "%" are shown on a weight basis. Examples 1 to 6 and Comparative Examples 1 to 5 The main component and the curing agent component shown in Table 1 below were dispersed and mixed immediately before coating to prepare a coating. Each paint was spray-coated on a blast-treated steel sheet (rust grade ISO Sa 2.5) so that the dry film thickness was as shown in Table 1, and was naturally dried for 10 days. With respect to the obtained coated plate, each of the friction coefficient measurement, the salt spray resistance, and the appearance of the coating film when the top coat was directly applied without a mist coat was tested. The results are shown in Table 1.
In the lower column.

[0017]

[Table 1]Table 1 (Units of blending components: parts) Paint composition Example 1 2 3 4 5 6 Main ingredient Epoxy resin solution Note 1) 11.4 8.6 14.3 10.0 10.0 7.1 Alkyl silicate 20.0 Condensate solution Note 2) Zinc powder (A) Note 3) 75.0Zinc powder (B) Note 4) 85.0 65.0 70.0 70.0 65.0 Pigment Silicon oxide Note 6) 14.0 21.0 Silicon carbide Note 7) 21.0 Black iron oxide Note 8) 7.0 Calcium carbonate Note 9) 20.0Talc Note 10) 20.0 solvent Xylene 6 6 6 6 6 Methyl isobutyl ketone 4 4 4 4 4 Hardener component Modified aliphatic polyamine 6.0 4.0 8.0 6.0 6.0 4.0 Solution Note 11) Dry film thickness (μm) 85 65 100 70 80 90 Film performance Coefficient of friction 0.48 0.45 0.50 0.45 0.40 0.53 Appearance of top coat * 12) Abnormal Same as left Same as left Same as left Same as left None Swell 10 10 10 10 10 10

[0018]

[Table 2]Table 1 (continued) (Components: parts) Paint composition Comparative example 1 2 3 4 5 Main ingredient Epoxy resin solution Note 1) 11.4 11.4 11.4 2.8 11.4 Alkyl silicate 32.0 Condensate solution Note 2) Zinc powder (A) Note 3) 34.0 89.0 75.0 Zinc powder (B) Note 4) 65.0Zinc powder (C) Note 5) 75.0 Pigment Silicon oxide Note 6) 14.0 21.0 14.0 Calcium carbonate Note 9) 55.0Talc Note 10) solvent Xylene 6 6 6 6 Methyl isobutyl ketone 4 4 4 4 Hardener component Modified aliphatic polyamine 6.0 6.0 6.0 2.0 6.0 Solution Note 11) Dry film thickness (μm) 85 85 85 85 20 Film performance Coefficient of friction 0.38 0.45 0.31 0.48 0.35 Appearance of top coat * 12) Abnormal Same as left Same as left Foaming Abnormal None None None Salt spray resistance * 13) Rust 10 6 10 10 6 Swell 10 10 10 10 10 Note 1) "Epicoat # 10" manufactured by Yuka Shell Epoxy
01 × 70 ”, solid content 70%, resin epoxy equivalent 450 Note 2) Product name“ B-102 ”, manufactured by Nippon Synthetic Rubber Co., solid content 2
5% Note 3) Average particle size 4.0μm, powder 85% 2μm or more Note 4) Average particle size 7.3μm, 2μm or more powder 95% Note 5) Average particle size 1.0μm, powder 2% or more 30% Note 6) Average particle size 4.2 µm, Mohs hardness 7.0 Note 7) Average particle size 5.0 µm, Mohs hardness 9.5 Note 8) Average particle size <5.0 µm, Mohs hardness 6.0 Note 9) Average Particle size 3.0 μm, Mohs hardness 3.0 Note 10) Average particle size 6.0 μm, Mohs hardness 1.0 Note 11) Product name “SANMIDE E-1001S” manufactured by Sanwa Chemical Co., Ltd.
Solid content 50%, polyamine amine value 100 * 12) Epoxy resin paint (Dai Nippon Paint Co., Ltd.)
Product name "Eponics # 30 Shitanurisabi color") xylene
3% diluted with a mixed solvent consisting of (1: 1)
Sprayed to a dry film thickness of 30μm
And after visually drying for one day, visually evaluate the appearance of the coating film.
Was. Note 13) Cross-cut the coating film and perform the salt spray test at 1500 hours
The evaluation was performed according to ASTM criteria.

As is clear from Table 1, the coatings of the present invention, Examples 1 to 6, all have a coefficient of friction of 0.40 or more, have excellent anticorrosion properties, and are overcoated without a mist coat. A good coating film was also obtained. On the other hand, in Comparative Example 1, in which the zinc powder having a particle diameter of 2 μm or more was less than 50%, Comparative Example 3 containing no pigment, and Comparative Example 5 having a small film thickness, the coefficient of friction was low. In Comparative Example 2 with a small amount of zinc powder and Comparative Example 5 with a small film thickness, the anticorrosion properties were inferior. In Comparative Example 4 in which the amount of the inorganic bond was excessive, much foaming was observed in the top coat.

[0020]

According to the method of the present invention, when the steel members are joined by the high-strength bolt friction joining method, the joining surfaces of the members can be made to have a friction coefficient of 0.40 or more. The paint of the present invention does not require advanced kelen which is to be employed in conventional inorganic zinc-rich paints, and does not require a mist coat in advance when applying anticorrosive paint since it does not become a porous film. Can be shortened, and coating efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a high-strength bolt friction joint.

[Explanation of symbols]

 a, a 'Steel member 1 High strength bolt 2 Nut 3,3' Washer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Mishima 1-18-18603 Nishikawara, Ibaraki-shi, Osaka (72) Inventor Hidenori Matsuno 3-1172-4 A101, Shimonaga, Nishinasuno-cho, Nasu-gun, Tochigi A101 (56) References JP-A-63-205373 (JP, A) JP-A-56-97578 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B05D 7/14 B05D 7/00 C09D 163 / 00 F16B 5/02

Claims (2)

(57) [Claims] In a method of joining steel members by a high-strength bolt friction joining method, a binder (i) comprising (A) an epoxy resin and a curing agent thereof as a coating-forming component at least on a joining surface of the members. )
And the inorganic binder (ii) in a weight mixing ratio of (25: 7)
5) to 20% by weight of a binder composed of (100: 0), (B) 2 μm in which the average particle diameter is 1 to 30 μm and 50% or more.
Zinc powder or zinc alloy powder having the above particle size
90% by weight and (C) a paint containing 1 to 40% by weight of a pigment having a Mohs hardness of 2.5 or more , to form a coating having a dry film thickness of 30 to 150 μm. Joining method. 2. The following components: (A) a binder (i) comprising an epoxy resin and a curing agent;
The weight mixing ratio with the inorganic binder (ii) is (25:75)
(B) having an average particle size of 1 to 30 μm and 50% or more having a particle size of 2 μm
Zinc powder or zinc alloy powder having the above particle size
90% by weight, and (C) 1 to 40% by weight of a pigment having a Mohs hardness of 2.5 or more as a coating film forming component. Coating paint for joint surfaces.