JP2534329Y2 - Anticorrosion bolts and anticorrosion metal fittings for bolts - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an anticorrosion bolt and an anticorrosion metal fitting for the bolt body, and more specifically, to an anticorrosion metal fitting for performing anticorrosion of the bolt using a so-called electrolytic protection method. The present invention relates to an anticorrosion bolt used by attaching the anticorrosion metal fitting.

(Prior Art) Generally, for the purpose of preventing corrosion of a metal body in contact with an electrolyte medium such as seawater or soil, a more anode-like metal body is used.
That is, a so-called galvanic anode method of electrically connecting low-potential metals and using the current generated by the potential difference between the two metal bodies to protect the former metal bodies has been put to practical use. I have.

This galvanic anode system does not require any external power supply, but only ionizes the low-potential metal on the anode side by the potential difference between the metals, thereby preventing the ionization of the metal for corrosion protection on the cathode side. Because it is a method of preventing corrosion of metal on the cathode side, it is widely used for corrosion prevention of objects for which it is difficult to install an external power supply, for example, ships and sluice gates where the object itself constantly moves, and even mechanical devices with complicated structures. I have.

The inventors of the present invention focused on applying such a galvanic anode method to bolts and conducted intensive research.

However, application to bolts has the following new problems.

That is, in the case of employing the galvanic anode method as described above, the condition is that the metal on the cathode side for anticorrosion purpose and the metal on the newly installed anode side are always in an electrically conductive state.

Generally, in order to obtain such an electrical conduction state,
When both metal bodies are separated, electric wires etc. are used. When both metal bodies are adjacent to each other, the electrical connection between the two metal bodies is performed using conductive bolts, nuts or mandrels. Electrical conduction is ensured.

However, it is of course impossible to use the bolts, nuts, mandrel, etc. as described above to prevent corrosion of the bolts themselves, and in the case of small objects such as bolts, the use of the above wires, etc. Is extremely unrealistic.

The present invention has been made to solve such a problem, and an object of the present invention is to make it possible to apply the galvanic anode method to a bolt as described above and to surely prevent corrosion of the bolt.

(Means for Solving the Problems) That is, a means adopted by the present invention for solving the above-mentioned problems is that the head 1a of the bolt main body 1 is provided with the anticorrosion fitting 3 made of a low-potential metal having a higher ionization tendency than iron. Is an anticorrosion bolt detachably mounted, and when the anticorrosion fitting 3 is mounted on the head 1a of the bolt main body 1, the electrically insulating paint applied to the bolt main body 1 is peeled off to remove the both. The anticorrosion fitting 3 is provided with a paint peeling means in order to make the electrical conduction state.

The feature of the anticorrosion bracket is that it is made of a low-potential metal that has a greater tendency to ionize than iron, and is configured to be detachable from the bolt to be anticorrosion. Is provided with a paint peeling means so that both paints are peeled off and both are electrically connected.

(Operation) Therefore, in the anticorrosion bolt having the above configuration, when the anticorrosion fitting 3 is attached to the bolt body 1, the electrically insulating paint applied to the bolt body 1 is coated with the anticorrosion fitting 3.
And comes into direct contact with the anticorrosion fitting 3, as a result of which the bolt and the anticorrosion fitting 3 are removed.
Become electrically conductive.

Therefore, when the bolt provided with the anticorrosion metal fitting 3 is used in an electrolyte medium such as seawater or tap water or even soil, a low-potential metal having a higher ionization tendency than iron constituting the bolt is used. Since the anticorrosion metal fitting 3 serves as an anode and conducts electricity, and thereby prevents the electric current on the bolt side, the bolt is prevented from being corroded.

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1 (a), reference numeral 1 denotes a substantially T-shaped cast iron bolt body, and a convex portion 2 having an inverted trapezoidal cross section protrudes from one end of a top surface of a head 1a. ， Electrical insulating paint is applied. In FIG. 2 (b), reference numeral 3 denotes a corrosion-prevention metal fitting made of zinc.
Is provided with a concave groove 4 which can be press-fitted from the side, and the concave groove 4 is formed to be slightly smaller than the convex part 2.

Conversely, a concave groove 4 may be formed on the top surface of the bolt body 1, and the convex portion 2 press-fittable into the concave groove 4 may be formed on the lower surface of the anticorrosion fitting 3.

As shown in FIG. 2, the anticorrosion metal fitting 3 is formed by press-fitting the convex portion 2 of the bolt main body 1 into the concave groove 4 to form the anticorrosion bolt 5. The paint on the first convex portion 2 is peeled off, and the two are in contact with each other to form an electrically conductive state, and the engagement between the convex portion 2 and the concave groove 4 prevents the anticorrosion fitting 3 from coming off. Is done.

The anticorrosion bolt 5 having such a configuration is used together with the nut 7 for the purpose of coupling the flange portions 6 of a buried pipe buried in the soil as shown in FIG. 3, for example.

In this case, as described above, the anticorrosion fitting 3 and the metal surface of the bolt body 1 come into electrical conduction with each other.
On the other hand, the soil itself in which such bolts 5 are buried is an electrolyte. Therefore, a potential difference is generated between the zinc-made anticorrosion fitting 3 and the iron-made bolt main body 1, so that zinc constituting the anticorrosion fitting 3 on the anode side of the potential difference is generated as zinc ions and flows out into the soil. Only the anticorrosion metal fitting 3 is corroded, so that corrosion of the iron bolt body 1 serving as the cathode is prevented.

When the anticorrosion fitting 3 is replaced, it can be easily detached from the bolt body 1 by hitting its side face with a hammer or the like, while the anticorrosion fitting 3 is made of zinc. There is an advantage that no damage is caused to the convex portion 2, and that the new anticorrosion metal fitting 3 can be easily mounted, which can greatly contribute to the replacement.

(Example 2) In Example 1 described above, the convex portion 2 provided on the head 1a of the bolt body 1 was press-fitted into the concave groove 4 provided on the anticorrosion fitting 3, and both were attached. It may be configured as follows.

In the figure, reference numeral 8 denotes an engaging projection protruding from both sides of the head 1a of the bolt body 1, reference numeral 9 denotes a concave groove formed in a substantially central longitudinal direction, and a central part of both sides of the concave groove 9. Is formed with a notch 10, and the bolt body 1 is coated with an electrically insulating paint.

Reference numeral 11 denotes a convex portion formed substantially at the center of the lower surface of the anticorrosion fitting 3, and a protrusion (not shown) is provided at the substantially center of the side surface of the convex portion 11. Reference numeral 12 denotes locking pieces protruding from both sides of the anticorrosion fitting 3, and a locking portion 13 is formed inward at an end thereof.

The present embodiment is configured as described above,
Is struck from above, the convex portion 11 fits into the concave groove 9 of the head 1a of the bolt body 1, and the protrusion of the convex portion 11 of the anticorrosion fitting 3 press-fits into the notch 10 of the head 1a. Then, at this time, the paint applied to the notch 10 of the bolt body 1 is peeled off by the protrusion of the convex portion 11, and the two come into contact with each other to be in an electrically conductive state. The locking portions 13 of 12 are locked by the locking projections 8 of the bolt body 1, so that the two are prevented from coming off.

When the anticorrosion fitting 3 is to be detached from the head 1a of the bolt body 1, it is hit from below the locking piece 12 of the anticorrosion fitting 3 so that the locking portion 13 and the locking projection of the bolt body 1 are locked. 8 is released, and the anticorrosion fitting 3 can be easily replaced.

Third Embodiment Further, it is also possible to simplify the configuration of each member of the second embodiment and configure as shown in FIG.

That is, a concave groove 9 is formed on the top surface of the bolt body 1, and a convex portion 13 formed to have a slightly larger width than the concave groove 9 so as to be able to be pressed into the concave groove 9 is formed on the anticorrosion fitting 3. The locking piece 12 of the anticorrosion fitting 3 protrudes from the lower surface in the same manner as in the second embodiment.
The engaging portions 13 of the bolt body 1 are engaged with the engaging convex portions 8 of the bolt body 1, and both are attached.

In this case, the paint in the concave groove 9 of the bolt body 1 is peeled off by the convex portion 14 of the anticorrosion metal fitting 3, and the two come into contact with each other to be in an electrically conductive state.

Contrary to this embodiment, a convex portion is formed on the top surface of the bolt body 1.
It is also possible to provide a groove 14 in which the convex portion 14 is press-fitted and formed on the lower surface of the anticorrosion fitting 3.

(Embodiment 4) Next, another embodiment of the anticorrosion bracket for bolts according to the present invention will be described.

In FIG. 6, 3 denotes the bifurcated anticorrosion metal consisting of zinc, an inner diameter l ₁ is formed slightly smaller than the outer diameter l ₂ of the threaded portion 1b of the bolt body 1.

The anticorrosion metal fitting 3 is used by being press-fitted from the side into the threaded portion 1b of the bolt body 1 connecting the flanges 6, 6 projecting from the nut 7, as shown in FIG.

Also in this case, the difference in size between the inside diameter l ₁ and the outer diameter l ₂ as described above, the threaded portion 1b of the bolt body 1 upon stuffing
Is peeled off, and the metal surface of the screw portion 1b and the anticorrosion metal fitting 3 are in direct contact with each other, and the bolt body 1 is anticorrosion with the occurrence of the above-mentioned potential difference.

The anticorrosion fitting 3 in the embodiment is a bolt body 1
Even if the screw portion 1b is damaged, it can be easily attached and detached, so that it can be used for existing bolts.

In addition, if the protruding portion 15 is provided along the inner peripheral surface of the anticorrosion metal fitting 3 as shown in FIG. Since it is accommodated in the concave portion 16 between the shaped portions 15, the disadvantage that the electrically conductive state between the bolt and the anticorrosion fitting 3 is hindered by the peeled paint can be avoided well.

In this case, if a convex portion 17 or a concave portion (not shown) is provided on the back surface of the anticorrosion fitting 3, a pipe 18 or a rod-like body can be fitted into the convex portion 17 or the like. Therefore, the work of attaching the anticorrosion fitting 3 to the bolt can be performed easily and reliably at the time of construction at the site, and thus there is an advantage that it can greatly contribute to the convenience of the construction work.

In the above embodiment, the anticorrosion fitting 3 is made of zinc. However, the material is not limited to zinc. For example, metals such as aluminum and magnesium can be used, and further, alloys of these metals can be used. In short, any metal that can serve as a current carrying anode, that is, a low-potential metal having a higher ionization tendency than iron forming the bolt may be used. However, from the viewpoint of the effectiveness of the electrode potential value and the possibility of long-term use, it is desirable to use zinc or an alloy of zinc and a small amount of aluminum.

Further, in the above-described embodiment, the case where the anticorrosion bolt or the anticorrosion metal fitting is used for coupling the flange portion of the buried pipe buried in the soil has been described, but the application of the anticorrosion bolt and the like is not limited thereto, and for example, seawater. Also, it can be used in tap water. The point is that the bolt may be used on the cathode side, and the anticorrosion fitting 3 may be used on the anode side in an electrolyte medium in which a potential difference can be generated.

In addition, the anticorrosion bolt and the anticorrosion metal fitting 3 according to the present invention can be sold as a so-called set, and the like.
Further, only the anticorrosion metal fittings 3 may be sold as a single item or the like, and the specific form of the transaction does not matter.

(Effects of the Invention) As described above, in the present invention, an anticorrosion bracket made of a low-potential metal having a greater ionization tendency than iron is mounted on the head of the bolt body, and at the time of such mounting, rust prevention treatment or the like is performed. The anticorrosion fitting is provided with a paint peeling means so that the electrically insulating paint of the painted bolt body is peeled off so that the two can come into contact with each other in an electrically conductive state.
Due to the generation of the potential difference in the galvanic anode system, only the corrosion-proof metal fitting side is corroded, and the corrosion of the bolt side is prevented.

Therefore, it is possible to employ a galvanic anode system, which is an extremely small anticorrosion target, and as a result, the bolt has a particularly remarkable effect that the anticorrosion effect is much better than before.

In addition, when the anticorrosion fitting is formed in a forked shape so that it can be attached to the screw portion of the bolt body from the side, it can be attached to the bolt with one touch, for example, compared to a general galvanic anode installation work such as a hull. This eliminates the need for complicated installation work using a mandrel or electric wires, so the workability is good.Each of the new and existing bolts is very easily fitted with anticorrosion fittings, There is an effect that the electrical conduction state can be obtained.

[Brief description of the drawings]

FIG. 1 shows an anticorrosion bolt as one embodiment,
Is a front view of the bolt body, and (b) is a side view of the anticorrosion fitting. FIG. 2 is a perspective view showing a mounted state. FIG. 3 is a front view showing a use state. 4 and 5 are perspective views of a main part of another embodiment. FIG. 6 is a front view of the anticorrosion fitting as one embodiment of the present invention. FIG. 7 is a front view of the same use state. FIG. 8 shows another embodiment of the anticorrosion fitting, wherein (a) is a front view and (b) is a cross-sectional view. DESCRIPTION OF SYMBOLS 1 ... Bolt body, 1a ... Head, 1b ... Thread part 3 ... Corrosion-proof metal fittings, 8 ... Locking protrusion, 12 ... Locking piece 13 ... Locking part

Claims (7)

(57) [Scope of request for utility model registration] An anticorrosion bolt comprising a head body 1a of a bolt body 1 and an anticorrosion fitting 3 made of a low-potential metal having a greater ionization tendency than iron is detachably mounted. When attached to the head 1a, the bolt body 1
The anticorrosion bolt is characterized in that the anticorrosion fitting 3 is provided with a paint peeling means so that the electrically insulating paint applied to the anticorrosion paint is peeled off and the two are electrically connected. 2. The method according to claim 1, wherein the paint peeling means is a head of the bolt body.
Claims of utility model registration which are convex portions provided on the lower surface of the anticorrosion fitting 3 for press-fitting into the concave groove provided on the top surface of 1a and capable of peeling off the paint applied to the concave groove at the time of press-fitting. 2. The anticorrosion bolt according to claim 1. 3. The method according to claim 2, wherein said paint peeling means is a head of the bolt body.
Anticorrosion fitting 3 to press-fit the convex part provided on the top surface of 1a
2. The anticorrosion bolt according to claim 1, wherein said groove is provided on the lower surface of said slab and is a concave groove capable of peeling off the paint coated on said convex portion during press-fitting. 4. Locking projections 8 are provided on both sides of the head 1a of the bolt body 1 and lockingly detachable from the locking projections 8 on both sides of the anticorrosion fitting 3. Locking piece having a portion 13 at the tip
The anticorrosion bolt according to claim 2 or 3, wherein 12 is provided. 5. The anticorrosion bolt according to claim 1, wherein said low-potential metal is zinc or a zinc alloy. 6. A bolt made of a low-potential metal having a higher ionization tendency than iron and detachably attached to a bolt to be protected from corrosion.
In addition, an anticorrosion metal fitting for a bolt is provided, which is provided with a paint peeling means so that when the bolt is mounted, the electrically insulating paint applied to the bolt is peeled off so that both are electrically connected. 7. A bolt made of a low-potential metal having a higher ionization tendency than iron and formed in a bifurcated shape so that it can be attached to the screw portion 1b of the bolt body 1 to be protected from the side. At this time, the inner diameter l ₁ is formed to be smaller than the outer diameter l ₂ of the threaded portion 1b of the bolt body 1 so that the electrically insulating paint applied to the threaded portion 1b of the bolt body 1 is peeled off and both are electrically connected. An anticorrosion metal fitting for a bolt, characterized by being made.