JP2650615B2 - Structure of perforated part for branch of cast iron pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a perforated portion for branching a cast iron pipe when a pipeline 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. Without branching work, it is complicated, and the effect on other users is not small. Therefore, in recent years, plumbing is generally done without cutting off the main pipe, installing a water tap with a saddle on the surface of the branch point of the cast iron pipe that has been dug down and exposed from the ground, and drilled from above through a shaft hole that runs through the center of the water tap. Through the hole for branching into the cast iron pipe, pull up the drill and close the water faucet to cut off the water, the shaft hole at the center of the faucet is closed at the upper end, and one of the faucet Is a well-known and commonly used technique in which a branch pipe is connected, then a water faucet is opened, and water is distributed from the pipeline to the branch pipe.

However, in this case, since the cast iron pipe is pierced after the water faucet is attached, the circular hole newly penetrated by the drill exposes the ductile cast iron, which is the material of the cast iron pipe, as it is, and continuously passes water. Because of the contact, it is inevitable that rust will be generated on the surface of the circular hole, and red rust will mix with tap water and slip into faucets such as homes, and the carefully adjusted water quality will change into polluted water called red water. This can easily result in frowning consumers.

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 cast iron 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 cast iron pipe beforehand as described above, drilling is performed.Therefore, a special procedure is required for fitting a corrosion-resistant 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, as shown in FIG. 4 (A), an inward expansion is provided with an upper flange 21a through a shaft hole 32a of a water tap 3a mounted on the outer peripheral surface of a cast iron pipe 1a. A cylindrical anticorrosion sleeve 2a having a projection 102 at the lower end is fitted into the circular hole 11a from above, and further from above the push rod 10a.
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 deforms, and eventually deforms into an outwardly bulging shape as shown in FIG. And pressure bonding with the anticorrosion layer 14a such as epoxy resin powder coating.

[0005] However, it has been recognized that such a modification of the degree of construction is still insufficient to prevent water from entering the inside of the anticorrosion sleeve (the surface of the circular hole). As a further improved prior art, FIG. There is an official 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. 6 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, and the bottom of the water faucet placed on the outer periphery of the cast iron pipe is not particularly limited. It is inevitable that a slight gap is formed between the cast iron pipe. That is, the outer peripheral surface 12b of the cast iron pipe 1b is, of course, circular, but eccentricity up to a limited numerical value, bending in the axial direction of the pipe, and the like are allowed. 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 water tap saddle 4 and the outer peripheral surface of the cast iron pipe, and to prevent the water tap from rattling due to uneven contact at the time of construction. The bottom surface 35b near the end is provided with a step so as to be slightly retracted from the outer peripheral surface of the cast iron pipe to provide the gap C intentionally.

[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 32b of the water faucet and chips from the drill cut into the gap C, it is difficult to remove the chips after drilling. It is inevitable that oxygen will dissolve in the water, and the oxidation reaction will proceed due to oxygen dissolved in the water. Also, when the chips generated during drilling flow freely in the gaps and damage the corrosion-resistant coating on the outer surface of the cast iron pipe and the bottom of the water faucet, the skin of the base metal is exposed and intensive oxidation occurs, causing rust. Forming a corroded portion E called Cobb,
Further, it may be a bad cause of 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.

[0008] In order to solve the above-mentioned problems, an object of the present invention is to provide a structure in which a powerful element causing rust is removed from a branch perforated portion of a cast iron pipe.

[0009]

According to the present invention, there is provided a structure of a branch hole for a cast iron pipe according to the present invention, wherein an anticorrosion sleeve with both flanges is fitted in a branch circular hole perforated in a cast iron pipe, and an upper flange of the anticorrosion sleeve is provided. Is intended for a structure in which the outer flange is engaged with the outer peripheral surface of the upper flange 21 of the anticorrosion sleeve 2. The above-mentioned problem was solved by fitting to the inner peripheral surface at the lower end of the P.32.

In this construction, the anticorrosion sleeve 2
It is a further desirable embodiment to add a configuration in which at least a part or all of the outer peripheral surface including the covering surface 22 of the inner peripheral surface 13 of the circular hole is covered with the rubber 24.

[0011]

Since the spacer which is in contact with the outer peripheral surface of the anticorrosion sleeve 2 and is fitted in the shaft hole of the water faucet is interposed, the gap C formed between the bottom surface of the water faucet and the outer peripheral surface tube of the cast iron pipe and the flow path are formed. Is blocked to prevent water from entering into it. 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.

[0012]

FIG. 1 is a longitudinal sectional front view of an embodiment of the present invention. The anticorrosion sleeve 2 fitted inside the circular hole 11 perforated for branching of the cast iron pipe 1 has a coating surface 22 in which the upper flange 21 is locked on the outer edge of the circular hole and the cylindrical surface comes into contact with the circular hole inner peripheral surface 13 in a right cylindrical shape. The lower end is pressed and bent to form a lower flange 23, which is pressed against the anticorrosion layer 14, such as cement lining or epoxy resin powder coating, which is the inner peripheral surface of the cast iron pipe. 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. And the axial hole 3 of the faucet 3
2 is in contact with the outer peripheral surface of the upper flange 21 of the anticorrosive sleeve 2, so that the water in the pipeline passes through the shaft hole 32 and the gap C. The system leading to the water was cut off to prevent flooding. Although the faucet 3 is omitted in this figure, the outer surface is a spherical valve body 3.
Needless to say, the rotary shaft 4 is provided with a rotating shaft for rotating and rotating the horizontal direction and opening and closing a branch pipe (not shown) mounted in a direction perpendicular to the plane of the drawing.

As for the shape of the anticorrosion sleeve 2, it is desirable to set the width of the upper flange to be larger than that of the prior art illustrated in FIG. 5 to ensure a sufficient contact area with the spacer 31. It is necessary that the contact length between the two be maintained at least 2 mm or more in the vertical direction. The material of the anticorrosion sleeve 2 can be selected from a wide range such as copper or copper-based alloys, stainless steel, plastic materials, and the like. In the case of the method of forming the 23, 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 or the like.

The spacer 31 is normally of a straight cylindrical shape, but its lower end is desirably located slightly apart from the outer peripheral surface 12 of the cast iron pipe. As described above, since the outer edge of the circular hole formed in the cylindrical cast iron pipe surface is not a straight line but a curved line, it is rather difficult to form the tip of the spacer along this curved line. If the contact surface with the upper flange is sufficiently secured, the concern that water flows into the gap C is almost eliminated. The material of the spacer may be selected from plastic materials such as hard rubber, polyethylene, hard vinyl chloride, and polyacetal. It is desirable that the anticorrosion sleeve 2 be tight enough to be in contact with the upper flange of the anticorrosion sleeve 2 so as to sufficiently perform the water sealing action. The elasticity and flexibility of the material are also difficult to discard.

In order to interpose the spacer 31 between the outer peripheral surface of the anticorrosion sleeve 2 and the inner peripheral surface of the water faucet, it is performed before the saddle 4 of the water faucet is fastened and fixed to the outer peripheral surface of the cast iron pipe. FIG. 2 is a view showing the bottom surfaces of the water faucet 3 and the saddle 4 which are screwed together before being mounted on the surface of the cast iron pipe, and the spacer 31 is located on the innermost side. If the spacer is fitted into the water tap in advance, if the material is hard rubber, it is sufficient to simply fit it on the inner surface of the water tap and the position will be fixed and it will be sufficient to mount it on the surface of the cast iron pipe as it is, but in the case of plastic material It is preferable to insert the inside of the water faucet and hammer and forcibly push it in, or to bond it with an adhesive or the like. In any case, once it is mounted on the surface of the cast iron pipe, subsequent correction and repair are difficult, so it is necessary to make sure that it does not come off before mounting. After the water faucet and the saddle are screwed together, they are mounted on the branch point of the cast iron pipe and the anticorrosion sleeve 2 is pushed into the shaft hole using a predetermined jig, and slides on the inner peripheral surface of the spacer. The most reasonable procedure is to form the lower flange 23 by pressing and bending the lower end of the lower flange 23 that has passed through to the lower circular hole 13 and passed therethrough with a jig.

FIG. 3 shows another embodiment of the present invention, which shows a state of the anticorrosion sleeve before being fitted into the water faucet, that is, a shape before the lower flange 23 is bent and formed. As shown in the figure, there are an example (A) in which only the covering surface 22 of the anticorrosive sleeve 2 is covered with the cylindrical rubber 24, and examples (B) and (C) in which the anticorrosive sleeve 2 is also covered on other surfaces. A unique effect of elastically deforming the inner peripheral surface 13 of the circular hole drilled in the cast iron tube so as to be more closely adhered thereto appears. In the case of FIG. 7 (C), the rubber has a function of making the contact not only with the inner peripheral surface of the circular hole but also with the spacer 31 fitted outside, and is one of the highly preferable embodiments for achieving the object of the present invention. is there.

[0017]

According to the structure of the perforated portion for cast iron pipe branching according to the present invention, as described above, in performing branch piping work without water interruption, mixing of cutting chips of a drill which may be feared at the time of drilling. In addition, it is possible to prevent the trouble near the end of the water pipe, such as the induction of oxidizing action and the generation of red water due to the oxidizing action, and to prevent the effort to maintain excellent water quality on the upstream side from being lost. is there. Without imposing a particularly large construction burden compared to the conventional technology,
It can be evaluated as a suitable example that creates a great sense of trust with a little consideration.

[Brief description of the drawings]

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

FIG. 2 is a bottom view of the same example at an intermediate stage.

FIG. 3 shows longitudinal front views of various embodiments of a corrosion protection sleeve (before implementation) according to (A), (B) and (C).

4 (A) and 4 (B) show variations in a vertical sectional front view of the prior art.

5 (A) and 5 (B) show variations of another prior art longitudinal front view.

FIG. 6 is a longitudinal 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 Separator faucet 4 Separator faucet saddle 11 Circular hole 12 Outer peripheral surface 13 Circular inner surface 14 Cement lining 21 Upper flange 22 Coating surface 23 Lower flange 24 Rubber 31 Spacer 32 Shaft hole 33 Inner surface 34 Valve 35 Bottom 41 Rubber packing C Crevice E Corrosion (rust bump)

Claims (2)

(57) [Claims] An anticorrosion sleeve with both flanges is fitted into a branch circular hole formed in a cast iron pipe, an upper flange of the anticorrosion sleeve is engaged with a circular edge of an outer surface of the cast iron pipe, and a lower flange is an inner surface of the cast iron pipe. A spacer 31 that contacts the outer peripheral surface of the upper flange 21 of the anticorrosion sleeve 2 is fitted to the inner peripheral surface 33 of the lower end of the axial hole 32 of the water faucet 3 in the branch perforated portion of the cast iron tube that is crimped onto the pipe. Structure of the perforated part for branching of cast iron pipe. 2. The cast iron tube according to claim 1, wherein at least a part or all of the outer peripheral surface of the anticorrosive sleeve 2 including the coating surface 22 in contact with the inner peripheral surface 13 of the circular hole is covered with rubber 24. The structure of the hole for branching.