JPH11108287A - Rust preventing equipment for metal-made fluid pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent generation of rust or the like in an opening part formed in a fluid pipe. SOLUTION: In this rust preventing equipment, a conductor wire 4 in a metal block 2 of low potential with an ionization tendency larger than a fluid pipe 8 is connected to a cap 14 for concealing a fixed bolt 12 mounted in a case 10, so as to form a different kind metal battery with the metal block 2 serving as an anode and an opening part 8a of the fluid pipe 8 serving as a cathode. By consuming the metal block 2 as a sacrifice anode, rust prevention in the opening part 8a is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a water pipe or a gas pipe buried in the ground, for example, for making an opening work for connecting a branch pipe or the like, or for making a metal part which easily rusts inside the pipe. The present invention relates to a rust preventive device that can prevent rust from being generated or corroded in an exposed portion when it is exposed.

[0002]

2. Description of the Related Art In general, taking the example of water supply, when performing water distribution work on a water pipe or the like already laid in the ground, the water pipe is not stopped without stopping the flow of water in the water pipe. After opening, a non-waterproof construction method of connecting a branch pipe or the like is used. In such a non-waterproof construction method, it is impossible to apply a rust preventive treatment such as painting to the metal surface of the opening exposed by drilling, so that the opening is generally left in a perforated state. It is.

[0003] As a result, rust may occur or corrode on the metal surface of the exposed opening, which causes deterioration of water quality.

[0004] In an iron water pipe or the like laid in an electrolyte medium such as soil, the oxygen concentration battery is determined by the difference between the dissolved oxygen concentration in running water in the water pipe and the oxygen concentration of water in soil. By the action, a potential difference is generated between the metal surface of the opening that is being made to flow and the surface of the water pipe that is in contact with the soil, and the metal surface exposed by the perforation is an anode,
A macro cell with the surface of the water pipe as the cathode is formed,
This is because a corrosion current flows from the metal surface.

In order to solve the above problems, in recent years,
There has been provided one in which a sleeve made of a synthetic resin is fitted to the inner surface of the opening after the opening is pierced to perform rustproofing.

[0006]

However, in the rust prevention treatment using the above-mentioned sleeve, a gap is formed between the outer surface of the sleeve and the inner surface of the opening unless the inner surface of the opening is made smooth, and water enters the gap. As a result, rust or the like may be generated on the metal surface after drilling.

In addition, the operation of mounting the sleeve in the opening is troublesome and requires a dedicated tool for mounting the sleeve, which increases the cost.

The present invention has been made in order to solve the above-mentioned problems. Rust is not applied to the above-mentioned opening or the exposed portion of the metal formed for some reason, and the exposed portion is not rusted. Etc. can be reliably prevented from occurring.
The purpose is to provide anti-rust tools.

[0009]

In order to achieve the above object, a rust preventive of the present invention performs a rust preventive treatment on a metal exposed portion of a metal fluid pipe where a metal material is directly exposed to the fluid. A rust preventive tool, wherein a metal lump having a greater ionization tendency than the metal constituting the fluid pipe and the metal lump and the metal exposed portion are directly attached to the fluid pipe or via an accessory attached to the fluid pipe. A conductive means for enabling an electrical conduction state is provided.

A conductive wire is connected to the connection terminal fixed to the metal lump, and the other end of the conductive wire is shaped like a sharp projection, and the tip of the projection is pressed against the fluid pipe,
It is preferable to make the metal block and the fluid pipe conductive.

It is preferable that the end of the conductive wire is a bolt pressed against the fluid pipe.

[0012] It is preferable that the end of the conductive wire is a blade portion of a metal pressing wheel attached to the fluid pipe.

[0013] It is preferable that the conductive means for enabling electrical conduction between the metal block and the exposed metal portion has an electrically shielded surface except for the metal block and the inside of the fluid pipe. .

Preferably, the shield is a film formed by painting.

According to the present invention, a dissimilar metal battery is formed in which the metal lump is used as an anode and the exposed metal part of the fluid tube is used as a cathode. Is prevented.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a rust preventive 1 of the present invention.
A rectangular plate-shaped metal block 2 made of zinc or a zinc alloy having a lower potential and a higher ionization tendency than ductile cast iron (or steel pipe), which is a material of a water main 8, which will be described later; 3 comprising a coated conductive wire 4 having
One mounting portion 3 is inserted into a bolt-shaped connection terminal 5 screwed to a corner of the upper surface of the metal lump 2 and is fixed by a nut 6.

The mounting portion 3, the conductive wire 4, the connection terminal 5, and the nut 6 are made of a metal having a higher potential and a smaller ionization tendency than the metal lump 2 in order to prevent their wear.
For example, it is formed of a copper-based metal.

The other mounting portion 3 of the conductive wire 4 is
It is directly or indirectly connected to the water main 8 near the opening 8a so as to be electrically conductive.

Hereinafter, an example of the connection of the other mounting portion 3 and the rust preventive action of the opening by the rust preventive device 1 will be described.

FIG. 2 shows that the water main pipe 8 made of ductile cast iron or the like buried in the soil 7 is cut by a required length and removed, and then, when the gate valve device 9 is installed in a water-free state, it is exposed by cutting. An example of connection in the case of preventing rust on the metal surface of both openings 8a is shown.

The installation of the gate valve device 9 is performed by an insertion method, but a detailed description of this method is omitted because it is not directly related to the present invention.

A case 10 mounted on the outer peripheral surface of the water main 8 so as to surround both openings 8a is provided with a fixing bolt 12 screwed into a plurality of female screw cylinders 11 projecting from the outer peripheral surface.
Is fixed by pressing the tip of the water main pipe 8 against the outer peripheral surface of the water main pipe 8.

Even when the outer peripheral surface of the water main 8 is coated with anti-corrosive paint, the fixing bolt 12 strongly presses against the outer peripheral surface of the water main 8 so that the coating film at that portion is peeled off. Then, the water main 8 and the fixing bolt 12 come into contact with each other by metal.

Reference numeral 13 denotes a special pressing wheel provided with a stopper metal fitting, which has a function of pressing the packing 22 to improve watertightness and a function of the water main 8.
And a function of preventing the slipping out.

The other mounting portion 3 of the conductive wire 4 in the rust preventive device 1 has a female screw tube 11 for concealing the fixing bolt 12.
Is connected to an iron cap 14 which is screwed to the outer peripheral surface of the opening end portion of the opening.

That is, as shown enlarged in FIG. 3, a female screw hole 14a is formed in the flat surface of the cap 14, and the mounting portion 3 is fixed to the cap 14 by screwing a bolt 15 into the female screw hole 14a. Fixing bolt 12 and bolt 15
Are electrically conducted through the conducting material 40.

The material of the fixing bolts 12 and the bolts 15 is preferably high-potential iron or the like which has a smaller ionization tendency than the metal block 2 in order to prevent its consumption. Further, if the cap 14, the mounting portion 3, the connection terminal 5, and the like are entirely coated so as not to be directly exposed to the earth, the effect is further improved. In the following embodiments, it is effective to electrically insulate the soil 7 except for the metal lump 2. As a method for this shielding, a resin-based coating film is effective.

As described above, when the rust preventive 1 is connected to the cap 14, the metal lump 2 and the water main 8 are electrically connected to each other, and the metal lump 2 is used as an anode, and the opening 8a of the water main 8 is closed. A dissimilar metal battery serving as the cathode is formed.

Accordingly, when the excavated work pit is backfilled and the water main 8 and the rust preventive device 1 are buried in the soil 7 which is an electrolyte, a potential difference occurs between the metal lump 2 and the water main 8. , The metal mass 2 on the anode side becomes zinc ions and soil 7
Elutes in. As a result, only the metal lump 2 is consumed as a sacrificial anode and current flow from the opening 8a is prevented.
Even if an oxygen concentration cell action occurs between the flowing water in the water main 8 and the water in the soil 7, the metal surface of the opening 8a exposed by cutting is less likely to rust or corrode.

This rust prevention effect is continued until the metal lump 2 is completely consumed. Therefore, the size of the metal lump 2 may be appropriately set according to the service life of the water main 8.

FIG. 4 is an enlarged view showing an example in which the rust preventive 1 is connected to the special pressing wheel 13 instead of the cap 14.

The special pressing wheel 13 includes a plurality of flanges 19 which can be fastened to the flange 16 on the case 10 side with a T-head mounting bolt 17 and a nut 18, and a plurality of pressing bolts 20.
And an arcuate claw 21 pressed toward the outer peripheral surface of the water main 8 by a sharp edge portion that can be cut into the outer peripheral surface of the water main 8 at the tip of the arcuate claw 21.

Reference numeral 22 denotes a packing which is pressed by the special pressing wheel 13 to maintain watertightness.

The mounting portion 3 of the conductive wire 4 in the rust preventive 1 is
The push bolt 20 is conductively connected to the push bolt 20, and the push bolt 20 abuts on the arcuate claw 21 in an electrically conductive state.
Bite into.

When the mounting portion 3 is fixed to the flange 19 in this manner, the arc-shaped claws 21 peel off the rust-preventive coating film of the water main pipe 8 and come into contact with each other. The pipe 8 is electrically connected to the pipe 8 via the special pressing wheel 13, and a dissimilar metal battery having the metal lump 2 as an anode and the opening 8 a of the water main pipe 8 (see FIG. 2) as a cathode is formed as described above. Is done.

As a result, the metal block 2 is consumed as a sacrificial anode, and the rust-preventing action of the opening 8a occurs.

The components of the special press wheel 13 are preferably made of a material having a lower ionization tendency than the metal lump 2 in order to prevent its wear.

FIG. 5 shows a split T-tube 23 attached to the outer peripheral surface of an iron water main 8 buried in soil (not shown).
In a construction method in which a circular opening 8a is formed in the side wall of the water main 8 by a drilling machine inserted from the branch pipe 24 side, and the flowing water in the water main 8 is branched to the branch pipe 24 side without interruption. An example is shown in which the metal surface of the opening 8a exposed by the perforation is rustproofed by the rustproofing tool 1. 25 is a gate valve device.

In this example, the connecting portion 3 of the conductive wire 4 of the rust preventive device 1 is connected to the right flange by a part of a T-head bolt 26 and a nut 27 for fastening the flanges 23a of the split T-tube 23 made of iron. 23a is connected so that metals may contact each other.

When the anti-corrosion coating is applied to the split T-tube 23, in order to improve the electrical conductivity between the mounting portion 3 and the flange 23a, the contact between the mounting portion 3 and the flange 23a is improved. It is preferable that a part of the rust preventive coating on the contact surface is removed or a sharp projection is formed on the contact surface of the mounting portion 3.

Even when the outer peripheral surface of the water main 8 is coated with rustproof coating, the inner surface of the split T-tube 23 on the side to which the mounting portion 3 is fixed and the outer peripheral surface of the water main 8 It is preferable to remove a part of the rust-preventive coating film on the contact surfaces of each other so that the metals contact each other.

When the rust preventive device 1 is connected in this way, the metal lump 2 and the water main 8 are brought into an electrically conductive state via the split T-tube 23, and the metal lump 2 is connected to the anode and the water main 8 A dissimilar metal battery having the opening 8a as a cathode is formed.

As a result, as described above, it is possible to prevent the metal block 2 from being consumed as a sacrificial anode and causing rust in the opening 8a.

FIG. 6 shows a state in which a saddle 28 is attached to an iron water main pipe 8 buried in soil (not shown), and a circular opening 8a is formed in the upper surface of the pipe wall. An example is shown in which the metal surface of the opening 8a exposed by the perforation is rust-proofed by the rust-proofing tool 1 in the method of attaching the faucet 29 in a water-free state.

In this example, a bolt 30 and a nut 31 for fastening the flanges 28a of the iron saddle 28 to each other are used.
The upper and lower flanges 28a are fixed to each other.
The saddle 28 is provided with an internal thread portion 51, to which the connecting portion 3 of the conductive wire 4 of the rust preventive tool 1 is fixed via a bolt 50, and the tip of the bolt 50 is brought into contact with the water main 8 to conduct electricity. It is in a state.

That is, even when the outer peripheral surface of the water main 8 is coated with rust prevention, the bolt 50 partially removes the coating film on the surface of the water main 8.

When the rust preventive device 1 is connected in this manner, the metal lump 2 and the water main 8 are electrically connected to each other through the saddle 28, and the metal lump 2 is connected to the anode and the opening 8 a of the water main 8. Is formed as a negative electrode.

As a result, as described above, it is possible to prevent the metal block 2 from being consumed as a sacrificial anode and causing rust in the opening 8a.

Also in this example, in order to prevent the bolts 30 and the nuts 31 from being worn, it is preferable that their materials are metals having a smaller ionization tendency than the metal lump 2.

FIG. 7 shows a two-part iron branch case 32 having a branch pipe part 32a, which is kept watertight, mounted on the outer peripheral surface of an iron water main pipe 8 buried in soil (not shown). An opening 8a having a C-shaped cross section is formed in the side wall of the water main pipe 8 at a position eccentric from the center of the pipe axis by the drilling machine inserted from above, and the flowing water in the water main pipe 8 is directed to the branch pipe part 32a side. In this example, a metal surface of an opening 8a exposed by perforation is rust-proofed by a rust preventive device 1 according to another embodiment of the present invention in a method of branching in a waterless state. 33 is a gate valve device.

In the rust preventive 1 of this embodiment, the conductive wire 4 as described above is omitted, and the metal lump 2 is directly fixed to the iron branch case 32 with a plurality of bolts 2a.

By providing such bolts 2a, the coating of the water main 8 is cut off by the 2a, so that a dissimilar metal battery using the metal lump 2 as an anode and the opening 8a of the water main 8 as a cathode can be used. It is formed. As a result, similarly to the above, it is possible to prevent the metal lump 2 from being sacrificed and consumed, thereby preventing the opening 8a from being rusted.

As described above, the rust preventive 1 of the present invention
If the water main and its accessories are already conductive,
The conductive wire 4 attached to the connection terminal 5 of the metal lump 2 made of zinc or the like is connected to an accessory part of the case 10 to be attached in contact with the water main 8, that is, the cap 14 or the special pressing ring 13. Flange 23a of the pipe 23 or the saddle 28, 2
Rust is generated in the opening 8a simply by fixing the metal block 2 to the anode 8a with the bolts 26 and 30 and the nuts 27 and 31 to form the metal lump 2 as the anode and the opening in the water main 8 as the cathode. Can be reliably prevented.

The present invention is not limited to the above embodiment.

The part to be connected to the conductive wire 4 may be any part other than the cap 14 and the special pressing ring 13 as long as it is an accessory part which is attached to the split main pipe or the like so as to be electrically connected to the water main 8.

The fluid pipe to which the present invention is applied may be a fluid pipe laid outside of the water main pipe 8 buried in the soil, for example, in contact with an electrolyte medium such as concrete, seawater, or groundwater.

In addition to the rust prevention of the opening 8a drilled in the above-mentioned watertight construction method, the present invention is also applied to rust prevention measures for the opening of other existing pipes that cannot be rust-proofed after drilling. sell.

The material of the metal lump 2 can be not only zinc or its alloy, but also aluminum or its alloy, magnesium or its alloy, or an alloy of these three kinds, or the like. Any metal that meets the conditions may be used.

It goes without saying that the shape of the metal lump 2 is not limited to that of the above embodiment.

[0061]

According to the present invention, the following effects can be obtained.

(A) Unlike the prior art, the fluid pipe or the accessory attached thereto is more likely to be ionized and has a lower potential, without performing a troublesome work of mounting a rust prevention sleeve in the opening. Rust can be reliably prevented from being generated in the opening only by connecting the connection terminals of the metal blocks in a conductive manner.

(B) According to the second aspect of the present invention, the metal lump and the metal exposed portion of the metal fluid pipe are brought into a low-resistance conductive state.

(C) According to the third and fourth aspects of the present invention, it is possible to connect a metal block extremely easily without performing any processing on a fluid pipe, a split T-shaped pipe or a saddle attached thereto. it can.

(D) According to the invention as set forth in claims 5 and 6, electrons are effectively supplied only to the exposed metal portions, and the rust prevention effect is improved.

[0066]

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a rust preventive of the present invention.

FIG. 2 is a central longitudinal side view of the rust preventive of the present invention applied when rust-proofing an opening cut for installation of a gate valve device.

3 is an enlarged cross-sectional view of a main part showing details of a connection example between a cap mounting portion and a metal lump in FIG. 2;

4 is an enlarged sectional view of a main part showing an example of connection of a special press wheel and a metal lump to the special press wheel in FIG. 2;

FIG. 5 is a vertical sectional front view showing an example in which a metal lump is connected to bolts and nuts for fastening a split T-tube.

FIG. 6 is a longitudinal sectional front view showing an example in which a metal lump is connected to saddle fastening bolts and nuts.

FIG. 7 is a longitudinal sectional front view showing an example in which a rust preventive device of another embodiment of the present invention is integrally fixed to a branch case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rust prevention tool 2 Metal lump 2a, 5 Connection terminal 3 Connection part 4 Conductive wire 6 Nut 7 Soil 8 Water main pipe (fluid pipe) 8a Opening (exposed metal part) 9 Gate valve device 10 Case 11 Female screw cylinder 12 Fixed Bolt 13 Special press ring 14 Cap 14a Female thread hole 15 Bolt 16 Flange 17 T-head mounting bolt 18 Nut 19 Flange 20 Push bolt 21 Bow claw 22 Packing 23 Split T-shaped pipe 23a Flange 24 Branch pipe section 25 Gate valve 26 T-head bolt 27 Nut 28 Saddle 28a Flange 29 Water faucet 30 Bolt 31 Nut 32 Branch case 32a Branch pipe part 33 Gate valve device 40 Conductive material 50 Bolt 51 Female thread

Claims (6)

[Claims] 1. A rust preventive device for rust-proofing a metal exposed portion of a metal fluid pipe in which a metal material is directly exposed to the fluid, wherein the metal material has a greater ionization tendency than the metal constituting the fluid pipe. A metal block and conductive means for enabling an electrical connection between the metal block and the metal exposed portion via an accessory attached directly to the fluid pipe or via an accessory attached to the fluid pipe. Rust prevention tool for metal fluid pipes. 2. A conductive wire is connected to a connection terminal fixed to a metal lump, and the other end of the conductive wire is formed into a sharp projection at the tip, and the tip of the projection is pressed against a fluid pipe, The rust preventive device for a metal fluid pipe according to claim 1, wherein the metal block and the fluid pipe are electrically connected. 3. The rust preventive device for a pipe opening according to claim 2, wherein the end of the conductive wire is a bolt pressed against the fluid pipe. 4. The rust preventive device for a metal fluid pipe according to claim 2, wherein the end of the conductive wire is a blade part of a metal press ring attached to the fluid pipe. 5. A conductive means for enabling electrical conduction between the metal block and the exposed metal portion has a surface electrically shielded except for the metal block and the inside of the fluid pipe. The rust preventive for a metal fluid pipe according to any one of 1 to 4. 6. The rust preventive device for a metal fluid pipe according to claim 5, wherein the shield is a film formed by coating.