JP2746124B2 - Corrosion prevention structure of perforated part for branching of metal tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a perforated portion for branching a metal pipe when a pipe branching from a water pipe to a home is constructed.

[0002]

2. Description of the Related Art It is often necessary to diverge water from a water supply pipe buried underground and distribute water to new consumers. If branch work is not performed, it is complicated, and if the water is cut off every time the work is performed, the effect on other users is not small. For this reason, in recent years, plumbing has generally been done without cutting off the main pipe, and a metal pipe that has been dug down from the ground and is exposed, mainly a cast iron pipe with a water tap with a saddle attached to the surface of the branch point, and a shaft hole that goes through the center of the water tap Through the circular hole for branching into the metal pipe, pull up the drill, close the water faucet and cut off the water flow, the shaft hole in the center of the plug is closed at the upper end, and A commonly used technique is to connect a branch pipe to one of the faucets, open the water faucet, and distribute water from the pipeline to the branch pipe.

However, in this case, since the drilling of the metal pipe is performed after the water faucet is attached, the circular hole newly penetrated by the drill exposes the material of the metal pipe as it is and constantly comes into contact with the water flow. Metal rust is unavoidable on the surface of the circular hole, and red rust mixes with tap water and gets into faucets such as homes, and the carefully adjusted water quality changes to polluted water called so-called red water, which is a problem for consumers. It is easy to be frowned upon.

As a conventional technique for improving this point, means for protecting the inner peripheral surface of a perforated circular hole by covering it with an anticorrosion sleeve made of a corrosion resistant material is mainly used.
Even in this case, a structure in which flanges are provided above and below the anticorrosion sleeve so that water does not flow directly to the inner surface of the perforation so as to be in close contact with the inner and outer surfaces of the metal pipe, and a device for forming the structure are attracting attention. . Since a water tap with a saddle is attached to the branch point of the metal pipe beforehand as described above, the hole is drilled.Therefore, a special procedure is required to fit the anticorrosion sleeve with a flange to the inner surface of the drilled circular hole. And it is natural that the device is necessary. For this purpose, for example, in Japanese Patent Publication No. 54-17164, an upper flange 21a is provided from above through a shaft hole 31a of a water faucet 3a mounted on the outer peripheral surface of a cast iron pipe 1a as shown in FIG. Cylindrical anticorrosion sleeve 2 having a downwardly bulging portion 102 at the lower end
a into the circular hole 11a, and push rod 10 from above.
1 is pressed down, and the anticorrosive sleeve 2
Press the inner surface of a. As the push rod is pushed down in the vertical direction, the bulging portion 102 of the anticorrosion sleeve 2a is pressed and plastically deformed, and eventually deforms into an outwardly bulging shape as shown in FIG. Alternatively, it is stated that the resin is pressed against the epoxy resin powder coating portion 14a.

[0005] However, it has been recognized that such a deformation of the construction is still insufficient to prevent water from entering the inside of the anticorrosion sleeve (surface of the circular hole), and a further improved prior art shown in FIG. There is a gazette. As shown in FIG. 2A, a push rod 104 having a pressing projection 105 rotatably supported by a sheath tube 103 at its lower end is lowered, and as shown in FIG. 2B, the lower end of an anticorrosion sleeve 2b having an upper flange 21b. Is pressed to form a lower flange 23b (more precisely, a pressed bent portion). Originally, the circular hole (cast iron tube) 1b is a circular hole, so that the edge of the circular hole is not a straight line but a curved surface, and the lower end of the cylinder is pressed and bent along the circular hole edge so that the lower flange is evenly formed. It is stated that it would be difficult to form without a pressing portion that can freely select an action point in front, rear, left and right and up and down as in this configuration.

[0006]

FIG. 8 is a longitudinal sectional front view showing an example of the prior art. However, the present invention is not particularly limited to the configuration shown here. It is inevitable that a slight gap is formed between the metal tube and the metal tube. In other words, the outer peripheral surface 12b of the metal tube 1b is, of course, circular, but eccentricity up to a limited numerical value, bending in the axial direction of the tube, and the like are allowed, while the saddle 4b of the water faucet is usually a standard. The size is fixed and constant regardless of the diameter of the branch pipe, and the diameter adjustment corresponding to the difference in the diameter of the branch pipe is performed by changing the diameter of the shaft hole of the water faucet screwed to the water faucet saddle. ing. However, as described above, since the hole edge of the hole formed in the circular pipe is formed by a curve, it is technically very difficult to accurately transfer the bottom surface of the faucet having a curved surface in close contact with the hole edge. In addition, since some unevenness is rather unfavorable because it causes rattling, usually, as shown in the figure, a rubber is provided at the lower part of the screw portion of the water faucet saddle 4b and both of the water straddling the water faucet bottom surface. The packing 41b is interposed to maintain the watertightness between the bottom surface of the faucet saddle 4b and the outer peripheral surface of the cast iron pipe, and the bottom of the shaft hole 31b so that the faucet does not rattle due to uneven contact during construction. A step is provided on the bottom surface near the end, and the gap C is intentionally provided by slightly retreating from the outer peripheral surface of the cast iron pipe.

[0007] Once the water faucet saddle 4b and the water faucet 3b are attached once, the gap C is in a positional relationship where it is difficult to clean from above.
When drilling work is performed through the shaft hole 31b of the water faucet, and chips chipped by the drill enter the gap C, it is difficult to remove the chips after drilling. It is inevitable that the oxygen will dissolve in the water, and the oxidation reaction proceeds due to the oxygen dissolved in the water, and it is difficult to wipe out the concern that the water quality deteriorates. In addition, when the chips generated during drilling flow freely in the gaps and damage the corrosion-resistant coating on the outer peripheral surface of the metal pipe and the bottom of the water faucet, the skin of the base metal is exposed and intensive oxidation occurs, causing rust. In some cases, a corroded portion E called a bump is formed, which may be a bad cause of further deteriorating water quality. The cause of poor water quality blamed at the faucet at the end, such as for home use, is a trivial obstacle caused by the downstream side of the piping such as the branch at the end rather than the basic one caused by the upstream upstream from the main pipeline. It is thought that it is often.

Next, an elastic seal ring of a water-swellable rubber material
It is a well-known technique to use a
For example, water expansion into the recess of the core fitted to the joint body
Japanese Utility Model Application Laid-Open No. 63-141 with a rubber seal ring fitted
No. 386, a vertical pipe for sewer pipe and manhole
Mortar with water expansion stop ring for water seal of connection
Prior Art of Japanese Utility Model Laid-Open No. 59-43585
There is also. However, this application is based on the fact that
Attached faucets, inevitable for newly created connections
Specified to prevent water intrusion into gaps between members
Therefore, any of the conventional technologies can be applied.
There is no room for it. Further solving the same problem as the present invention
There is also a technique disclosed in Japanese Patent Application Laid-Open No. Hei 7-139678.
Fits an O-ring on the outer peripheral surface of a close contact core made of elastic flexible material
Piercing by inserting, inserting, and expanding the diameter of the insertion rod.
Press inward and use the difference in outer diameter of the insertion rod to punch the tight core.
Deforms so as to be pressed against the inner surface of the hole
The configuration in which the combined O-ring is also pressed is shown. Only
The water sealing force of the O-ring itself is
The elastic flexible material of the close contact core behind
However, even if it is slightly
There is a concern that the water sealing force will decrease as you try to restore the shape
I wonder if it can't be wiped. In order to solve the above problems, an object of the present invention is to provide an anticorrosion structure in which a leading element causing rust is removed from a branch perforated portion of a metal pipe.

[0009]

According to the present invention, the anticorrosion structure for a branch hole of a metal tube according to the present invention is provided by attaching an anticorrosion sleeve 2 having upper and lower flanges 21 and 23 to a branch hole 11 formed in the metal tube 1. The upper flange 21 is engaged with the upper edge of the circular hole of the outer peripheral surface 12 of the metal tube, and the lower flange 23 is engaged with the inner peripheral surface 13 of the metal tube.
In the anticorrosion structure of the branch perforated part of the metal tube to be crimped to
Carved on the outer peripheral surface of the upper flange 21-1 of the anticorrosion sleeve 2-1
The O-ring 25 fitted into the cut groove 24 is attached.
At the time of drilling, a sufficient interval S is maintained such that the maximum outer diameter does not contact the shaft hole 31 of the water faucet 3, and the vehicle enters from the interval S.
When flowing through water, it expands its original volume 2-3 times and
This problem has been solved by using a water-swellable rubber material that reliably closes the interval S.

In this configuration, the upper flange 2 is replaced with an O-ring that fits into the cut groove of the upper flange of the anticorrosion sleeve.
1-2, a cylindrical ring 26 is attached over the entire outer peripheral surface,
Circular ring 26, mounted upon Chi coercive sufficient spacing S to the extent that the maximum outer diameter is not in contact with the shaft hole 31 of the diversion plug 3 is in,
At the time of passing water that comes into contact with water entering from the interval S,
The capacity is expanded 2-3 times to securely close the space S.
A configuration made of a water-swellable rubber material may be used.

Alternatively, in the above configuration, the entire outer peripheral surface of the upper flange 21-3 and the covering surface 22-3 is covered instead of the cylindrical ring, and is attached to the inner peripheral surface 13 of the metal pipe of the lower flange 23-3. Deformed ring 2 that also clamps on the inner surface
7 and the deformed ring 27 has a maximum
While the outer diameter is sufficient to prevent contact with the shaft hole 31 of the water faucet 3
Keeps the gap S and comes into contact with water entering from the gap S
When passing water, the original volume expands two to three times to establish the interval S.
A configuration made of a water-swellable rubber material that actually closes is also a preferred embodiment.

[0012]

The spacing S is maintained between the faucet shaft hole 31 facing the upper flange outer peripheral surface of the anticorrosion sleeve 2 and the shaft of the faucet 3 already mounted at the perforated position on the outer periphery of the metal pipe. Since there is no contact even if it fits through the hole, there is no fear of damaging the rubber O-ring, cylindrical ring, or deformed ring that has been externally fitted to the upper flange, while maintaining a reliable expansion function. I have. And even if water in the pipe enters through the gap S from the shaft hole of the water faucet after installation, the externally fitted rubber ring immediately starts reacting with water and is 2-3 times longer than at the time of attachment. To close the gap S and prevent the subsequent inundation, so that the gap between the gap C remaining between the bottom surface of the water faucet and the outer peripheral surface of the metal pipe and the flow path is blocked. Intrusion of water into it is completely cut off. Therefore, even if chips are generated in the drilling operation at the time of drilling and remain in the gap C without being removed, the opportunity for reaction with oxygen is lost due to the cut off of contact with water, and an oxidizing action occurs. Absent. For this reason, the water flow is not contaminated by red rust, and the concern of water quality deterioration due to the structure of the perforated portion is completely eliminated.

[0013]

FIG. 1 is a longitudinal sectional front view of an embodiment of the present invention. As an example of a metal pipe, a ductile cast iron pipe, which occupies a major part of city water supply, is mostly applicable, but the present invention is applicable to other metal pipe types, for example, a steel pipe lined with a synthetic resin. You may. The anticorrosion sleeve 2-1 fitted inside the circular hole 11 perforated for branching of the cast iron tube 1 has the upper flange 21-1 engaged with the outer edge of the circular hole, and covers the inner peripheral surface of the circular hole in a straight cylindrical shape. The coating surface 22-1 is formed, and the lower end is pressed and bent to form a lower flange 23-1, and a cement lining or an epoxy resin powder coating 1, which is an inner peripheral surface of a cast iron pipe.
4 and crimped. A rubber packing 41 is interposed between the bottom surface of the water faucet 3 and the water faucet saddle 4 which are integrally screwed and mounted on the outer peripheral surface 12 of the cast iron pipe and the outer peripheral surface of the pipe, thereby providing a water sealing action. Plays. An O-ring 25 made of a water-expandable rubber material fitted into a cut groove 24 formed at an arbitrary position on the upper flange 21-1 is provided at an interval formed between the shaft hole 31 of the water tap 3 and the upper flange 21-1. It reacts with the water that has entered through S and expands, and its capacity doubles, swells from the kerf and closes the gap S, and prevents water from further entering and reaching the gap C.

The structure of the anticorrosion sleeve and the method of forming the same are as follows:
Basically, it is efficiently formed by the prior art of FIG. 7 proposed by the applicant himself. That is, engraved grooves 24 cut into the upper flange 21-1 of anticorrosion sleeve 2-1 molded into a straight cylindrical with upper flange as shown in FIG. 2 (A), the above state of unreacted to cut the groove Almost the same as the outer diameter of the flange
An O-ring 25 made of a water-expandable rubber material having an outer diameter is fitted. Since the outer diameter of the upper flange 21-1 is set sufficiently smaller than the inner diameter of the water faucet shaft hole 31, the anticorrosion sleeve is fitted into the water faucet without contact as shown in FIG. .
Here, when the push rod 105 having the pressing projection 104 as shown in FIG. 7 is fitted into the anticorrosion sleeve and the tip of the sleeve is pressed and bent to form the lower flange 23-1, the state shown in FIG. .

As for the shape of the anticorrosion sleeve 2-1, it is desirable that the width of the upper flange is set to be larger than that of the prior art illustrated in FIG. In general, the material of the anticorrosion sleeve 2 can be selected from a wide range such as copper or copper-based alloys, stainless steel, plastic material, etc. Press and bend lower flange 23
In the case of the method of forming, a copper material is most advantageous because the workability of the material is a major factor. However, stainless steel is preferred if emphasis is placed on corrosion resistance. In this case, a jig capable of applying a strong forming force, such as a hydraulic jack, is effective. In addition, various plastic materials can also serve the purpose in that they do not adversely affect the water quality, but it is generally difficult to plastically deform the plastic material at room temperature to form the lower flange. It may be necessary to add a heater configuration or the like.

The material of the O-ring 25 is preferably made of natural rubber, neoprene rubber, ethylene propylene rubber or the like, mixed with a strong water-absorbing substance, for example, an acrylic resin, and kneaded and formed. The water-swellable rubber material used in this example has a property of swelling two to three times the original volume three days after being immersed in water, and a variety that does not affect the water quality is selected. There is no particular limitation on the shape of the O-ring, but it is preferable that the O-ring be rectangular in the sense that the O-ring fits as large a capacity as possible in a cut groove having a limited cross-sectional shape.

Although not shown in this figure, the water faucet 3 horizontally rotates a valve body having a spherical outer surface, and also opens and closes a branch pipe (not shown) mounted in a direction perpendicular to the paper surface. Needless to say, it has a rotation axis.

FIG. 3 shows another embodiment of the present invention. FIG. 3A shows the state of the anticorrosion sleeve 2-2 before being fitted into the water faucet, that is, before bending the lower flange 23-2. It is the shape of. As shown in FIG.
-2, a cylindrical ring 2 made of a water-expandable rubber material
It is a requirement that the space S can be maintained even after the outer diameter of the upper flange portion on which the ring is externally fitted is still fitted into the faucet shaft hole 31 as shown in FIG. If there is intrusion of water from inside the pipe, the circular ring 26 reacts with water and expands as shown in FIG. 3C, and the effect of blocking the intrusion of water into the gap C is the same as in the previous example.

FIGS. 4A and 4B show still another embodiment of the present invention. In addition to an upper flange 21-3 as shown in FIG. A modified ring 27 made of a water-swellable rubber material is fitted over the entire surface of the anticorrosion sleeve, including the entire surface of the anticorrosion sleeve. The lower end of the anticorrosion sleeve inserted into the water faucet shaft hole is plastically deformed by pressing and forming the lower flange 23.
When -3 is formed, the cement lining 14 on the inner peripheral surface of the cast iron pipe is provided near the lower end of the deformed ring as shown in FIG.
And the inner surface of the lower flange of the anticorrosion sleeve. As a result, the water expansion at the outer periphery of the upper flange prevents entry from the direction of the water faucet shaft hole, and the water expansion at the inner surface of the lower flange also prevents entry from inside the main pipe (inside the cast iron pipe). Waterproof action is synergistic.

FIG. 5 shows another embodiment. In FIG. 5A, the O-ring 25 of the first embodiment is followed, and a normal rubber ring 28 is externally fitted to a straight cylindrical covering surface before pressing. This ensures a press-fit state between the inner periphery of the cast iron pipe after molding and the inner surface of the lower flange of the anticorrosion sleeve, and has a specific action to ensure a water sealing action. In the example of FIG. 2B, an O-ring 25 is fitted into the cut groove 24 on the upper flange, and a cylindrical ring 29 of a water-expandable rubber material is provided on the covering surface (including the inner surface of the lower flange after molding). This is an example of fitting externally, and it is wise to select them appropriately according to the situation.

[0021]

As described above, the anticorrosion structure of the perforated portion for cast iron pipe branching according to the present invention, when performing branch piping work without water interruption as described above, reduces the possibility of drill chips being drilled. Prevents problems near the end of water pipes such as contamination, induction of oxidizing action, and generation of red water due to oxidizing action, and the effect of preserving so that efforts to maintain excellent water quality on the upstream side are not lost. There is.
It can be evaluated as a suitable example that does not impose a particularly large construction burden as compared with the prior art, and that a little consideration breeds a great sense of reliability.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of an embodiment of the present invention.

FIG. 2 shows an anticorrosion sleeve before molding (A) showing the intermediate stage of the same example, during mounting (B), and the whole immediately after mounting (C).
It is a vertical front view.

3 (A), 3 (B) and 3 (C) are longitudinal sectional front views of another embodiment of the anticorrosion sleeve 2 (before molding), immediately after installation, and after reaction with water according to another embodiment of the present invention.

4 (A) and 4 (B) show a longitudinal sectional front view of a further embodiment of the anticorrosion sleeve (before molding) and immediately after installation.

5 (A) and 5 (B) are longitudinal sectional front views of a corrosion prevention sleeve (before molding) according to still another embodiment.

6 (A) and 6 (B) are longitudinal sectional front views showing a conventional procedure.

7 (A) and 7 (B) show another prior art procedure in a longitudinal sectional front view.

FIG. 8 is a vertical sectional front view showing a problem of the conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cast iron pipe 2 Corrosion prevention sleeve 3 Mixing faucet 4 Mixing faucet saddle 11 Circular hole 12 Outer peripheral surface 13 Inner peripheral surface 14 Cement lining or epoxy resin powder coating 21 Upper flange 22 Coating surface 23 Lower flange 24 Cut groove 25 O-ring 26 Cylindrical ring 27 Deformed ring 28 Rubber ring 29 Cylindrical ring 31 Shaft hole 41 Rubber packing C Clearance S Spacing

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Ichiro Shiomi 1-12-19 Kitahorie, Nishi-ku, Osaka-shi, Osaka Inside Kurimoto Ironworks Co., Ltd. (56) References JP-A-7-139678 (JP, A) Kaihei 3-96794 (JP, A)

Claims (3)

(57) [Claims] 1. An anticorrosion sleeve 2 having upper and lower flanges 21 and 23 is inserted into a branching circular hole 11 formed in a metal tube 1 and the upper flange 21 is connected to an upper edge of the circular hole of the outer peripheral surface 12 of the metal tube. The lower flange 23 is locked, and the lower flange 23 is cut into the outer peripheral surface of the upper flange 21-1 of the anticorrosion sleeve 2-1 in the structure for preventing the branching hole of the metal tube to be pressed against the inner peripheral surface 13 of the metal tube.
The O-ring 25 fitted into the groove 24 is
Maintain a sufficient interval S such that the large outer diameter does not contact the shaft hole 31 of the water faucet 3 and come into contact with water entering from the interval S.
When passing water, the original volume expands 2-3 times and
An anticorrosion structure for a perforated portion for branching a metal pipe, which is made of a water-swellable rubber material that is reliably closed . 2. The cylinder according to claim 1 , wherein a cylindrical ring 26 is formed over the entire outer peripheral surface of the upper flange 21-2 in place of the O-ring fitted into the cut groove of the upper flange of the anticorrosion sleeve. 箇形ring 26 has a maximum outer diameter Chi <br/> coercive sufficient spacing S so as not to contact with the shaft hole 31 of the diversion plug 3 at the time of mounting, and, in contact with water which enters from the space S through Water time
, The original volume is expanded 2-3 times and the interval S is securely closed.
An anticorrosion structure for a perforated portion for branching a metal pipe, characterized by being made of a water-swellable rubber material to be closed. 3. The metal pipe inner peripheral surface 13 of the lower flange 23-3, while covering all outer peripheral surfaces of the upper flange 21-3 and the covering surface 22-3 instead of the cylindrical ring. fitted around the profiled ring 27 which挾着also on the inner surface of, said different-shaped ring 27, the maximum outer diameter during attachment
A sufficient interval S that does not contact the shaft hole 31 of the water faucet 3
At the time of passing water that keeps and comes into contact with water entering from the space S
, The original volume is expanded 2-3 times and the interval S is securely closed.
An anticorrosion structure for a perforated portion for branching a metal pipe, characterized by being made of a water-swellable rubber material to be closed.