JPH04312285A - Structure for branching bore hole section for cast iron and its construction method and device - Google Patents

Abstract

PURPOSE:To prevent a bore hole section which divides water to individual dwelling houses out of a cast iron pipe for water supply, from being corroded. CONSTITUTION:A sleeve 1 made of corrosion resistant material is fitted in a circular hole bored in a cast iron pipe 2. The sleeve 1 is made up of an upper surface flange 11 and of a cylindrical section 12. An insertion pipe 41 is pushed in the inside of the sleeve 1. Let the bent section 43 of a hook 42 coupled in the insertion pipe 41 come out of the cut-out 44 of the insertion pipe. The lower end section of the sleeve is pushed so as to be bent by the corner of the bent section, so that a lower surface flange 13 is thereby formed while being tightly adhered on the inner surface of the pipe. This constitution thereby prevents drainage from coming out of each faucet of dwelling houses.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to the structure of a branching hole when water is distributed from a water pipe to each residence.

0002

[Prior Art] In order to connect a supply pipe that distributes water from the main water pipe to each residence, a circular hole is drilled at the desired location of the water pipe (mostly ductile centrifugal cast iron pipe) and a water distribution faucet is installed. There must be. However, if a circular hole is simply drilled into a pipe and the inner surface of the hole is left exposed to running water, the metal surface will corrode and rust, causing red water containing red rust to come out of household faucets. In order to prevent this, a measure has been proposed in which a sleeve made of another corrosion-resistant material is fitted into the circular hole without exposing the inner surface of the circular hole of the tube. For example,
In Publication No. 17164, as shown in FIGS. 6(a) and 6(b), the sleeve 1a is fitted onto the tip of the insertion rod 41a, and then this sleeve 1a is inserted into the circular hole 21a of the iron pipe 2a with the insertion rod 41a. A state in which the flange 11a provided on the outer periphery of the rear end hits the periphery of the circular hole and comes to a dead end (Figure (A))
Then, by pushing the insertion rod in, the tapered surface 6 at the tip of the insertion rod pushes the inwardly bulging portion 12a of the sleeve 1a outward on the inner circumferential surface of the hole, and extends it outward beyond the inner circumferential edge of the circular hole. The end of the sleeve is bent (Figure (B)). That is, sleeve 1a
It is said that by attaching this to the circular hole 21a, problems caused by the branching hole, such as generation of red water and obstruction of water flow, were solved.

0003

[Problem to be Solved by the Invention] In the prior art cited above, the exposed inner surface of the circular hole is covered with a corrosion-resistant material, such as a sleeve made of copper pipe, to prevent direct contact between cast iron and running water. Although it looks like this, the insertion rod is used like a mandrel to press the sleeve inside the circular hole and simply push out the inwardly bulging part outwards, so this pushed out part is the hole on the inner surface of the tube. It is not possible to expect reliable contact with the edge. Since a circular hole is drilled in a circular tube, the hole edge on the inner surface of the tube is not a circle on a horizontal plane, but a circle on a curved surface, and even if a uniform pressing force is applied from the center of the circular hole, it will not curve. It is not possible to form along extrusions. Therefore, it is thought that there are extremely many chances for the flowing water in the pipe to be pushed by the water pressure and enter through the gap that is expected to exist at the contact area between the hole edge and the sleeve. In particular, in the case of ductile centrifugal cast iron pipes, a lining layer of cement mortar is formed on the inner surface of the pipe to prevent corrosion, so when drilling from the outer surface of the pipe, it is not always possible to drill a circular hole that is an extension of the circular hole in the metal part. The edges of the holes in the lining layer often chip or crack, resulting in peeling that is larger than the holes in the metal part. In the example cited earlier, it is impossible to cover up this missing lining layer, so it must be said that the cause of red water outbreak still remains. In order to solve the above-mentioned problems, the present invention aims to form a corrosion-resistant sleeve that closely fits into a branching hole and maintains a water sealing effect between the sleeve and the cast iron pipe.

0004

[Means for Solving the Problems] In the structure of the perforated part for branching of a cast iron pipe according to the present invention, the upper flange of the double-flanged sleeve made of a corrosion-resistant material engages with the circular hole edge on the outer surface of the pipe,
The cylindrical portion of the sleeve covers the inner surface of the circular hole, and the lower flange of the sleeve extends from the edge of the circular hole to the inner surface of the tube and is crimped, thereby solving the above problem.

In addition, in order to construct the above structure, a circular hole is bored at a desired position in the cast iron pipe, and the sleeve has a flange attached to the upper surface, has an outer diameter slightly smaller than the outer diameter of the circular hole, and has a length. A cylindrical part that exceeds the pipe thickness is made of a corrosion-resistant material, the sleeve is inserted into the circular hole, the upper flange is locked to the hole edge on the outer surface of the pipe, and a coaxial insertion pipe is pushed into the sleeve from outside the pipe to form the cylindrical part. Discloses a method in which the outer surface is expanded until it comes into close contact with the inner surface of the circular hole, and then the lower part of the cylindrical portion is pushed and bent from the hole edge toward the inner surface of the tube using the bent portion of the hook extracted from the insertion tube, thereby forming a crimped lower surface flange. did.

[0006] Furthermore, as a device used only for carrying out the above construction method, a hook with a bent tip is inserted into a highly rigid insertion tube, and the insertion tube is inserted into a saddle and a sleeve holder fixed to the upper surface of the insertion tube. The insertion tube is housed so that it can be raised, lowered, and rotated via a spring material surrounding the sleeve, and a rotation handle is fixed to the upper end of the insertion tube that protrudes from above the sleeve holder.
A male thread is carved into the upper end of the hook that protrudes further from the upper end of the insertion tube, and a nut screwed into the male thread is engaged with the upper surface of the rotating handle, and the lower bent portion of the hook is a notch provided below the insertion tube. A configuration that allows the tube to protrude from the tube to the outside of the tube has been disclosed.

[0007]

[Function] In the branching perforation according to the present invention, the sleeve lower flange is provided which is crimped to the inner peripheral surface of the pipe to the hole edge in the pipe, which is formed by a circumferential line formed on a curved surface, so there is almost no concern that running water will infiltrate. It was resolved in The sleeve is made of a corrosion-resistant material with high plasticity, and its lower flange is formed by strong plastic deformation, resulting in a type of cold forge welding, with no gap between the sleeve and the inner circumferential surface of the pipe, leaving room for oxygen to exist. Since there is no water left, there is no longer any risk of red rust coming from here and supplying red water to households.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The contents of the present invention will be specifically explained below with reference to the drawings. FIG. 1 shows an embodiment of the invention, in which a copper sleeve 1
consists of an upper flange 11 and a cylindrical portion 12 having an outer diameter slightly smaller than the inner diameter of a circular hole 21 bored in the cast iron pipe 2. When the sleeve 1 is inserted into the circular hole 21, the upper flange 11 is locked to the outer hole edge 22 of the circular hole of the cast iron pipe 2. When the insertion tube 41 of the construction device 4 is pushed in from above the sleeve in this state, since the insertion tube has high rigidity and the sleeve is made of a corrosion-resistant material and has high plasticity, the pressing force from the outer circumferential surface of the insertion tube causes the cylinder of the sleeve to The portion 12 is laterally expanded and pressed against the inner surface of the circular hole. The length l of the sleeve cylindrical part is the lining 2
Since it is longer than the wall thickness T of the cast iron pipe including 5, the cylindrical part 12
The tip protrudes into the tube.

FIG. 2 shows that the bent portion 43 at the tip of the hook 42 that has been fitted into the insertion tube 41 is pulled out of the tube through a notch 44 made by breaking the lower part of the insertion tube, and the corner of this bent portion is inserted into the sleeve. The bottom flange 13 is forcibly formed by pressing and bending the lower end of the tube and extending it from the inner hole edge 24 of the circular hole along the inner surface of the tube. In this state, attach the hook 42 to the inner hole edge 24.
When the sleeve is rotated 360 degrees along the curved surface of the tube, the lower end of the sleeve is pressed and bent over the entire circumference to form a curved lower surface flange that is crimped onto the inner surface of the tube.

FIGS. 3 and 4 are a partially longitudinal front view and a partially longitudinal side view showing the construction device 4 of the present invention, in which the sleeve 1 is inserted into the circular hole 21 bored in the cast iron pipe 2, and This is the state at the time when the insertion tube 41 is inserted into the cylindrical portion 12. A hook 4 having a bent portion 43 at the tip is disposed inside the insertion tube 41.
2 is fitted inside, and a notch 44 is provided at the bottom to allow the bent portion 43 to be pulled out of the tube. However, a spring material 48 is interposed inside the sleeve holder 47 so as to surround the outer periphery of the insertion tube 41. Thrust bearings 49 are interposed above and below the spring material 48, so the insertion tube 41 is connected to the rotating handle 4.
If you press 5 from above, it will overcome the biasing force of the spring material and descend, and if you release the force, the spring material will cause it to rise back to its original state. Moreover, since a thrust bearing is involved, the structure allows the entire structure to be freely rotated and also to be freely raised and lowered. Rotating handle 45
The male threaded portion 5 of the hook 42 further protrudes from the upper end of the hook 42.
0, and a nut 51 is screwed onto this male thread and is locked onto the upper surface of the rotating handle 45, so that the entire hook is suspended.

5(a), (b), and (c) schematically show the construction procedure using this device. When the nut 51 is screwed upward from the state shown in FIGS. 3 and 4, the hook 42 is inserted. It moves downward within the tube 41, and finally its bent portion 43 leaves the lower end of the insertion tube and is exposed to the space (Figure I). In this state, when the entire hook is manually rotated 180 degrees within the insertion tube, the protruding position of the bent portion 43 will be directly below the position of the notch 44 of the insertion tube (Figure 2). Here, when the nut 51 is screwed downward, the hook 42 relatively moves up inside the insertion tube, but the bent part 43 fits into the notch 44 and rises inside the tube with protruding outside, and the hook bends. The corner portion of the portion 43 abuts against the cylindrical portion of the sleeve that is in contact with the inner edge of the circular hole, and is bent upward to form a portion of the lower flange 13 (FIG. C). When the rotating handle 45 is rotated in this state, the bent portion 43 of the protruding hook successively presses and bends the lower end of the sleeve that comes into contact with it. At this time, the inner hole edge 24 is not a horizontal circumferential line but a curved circumferential line as described above, but the spring material 48 expands and contracts to reduce the distance between the pressing surface of the hook and the inner hole edge. To form a lower flange surface that is evenly crimped to the curved surface as a whole while absorbing the differences.

[0012] In another preferred embodiment, the hook can be moved up and down within the insertion tube by operating a hydraulic cylinder instead of by advancing and retracting a screw. Further, in this embodiment, pure copper is used as the material for the sleeve, but any material may be used as long as it has corrosion resistance and high plasticity, such as copper alloy, stainless steel, or plastic. Furthermore, applying shape memory alloy to the sleeve is also an attractive example of use as a structure for the branching perforation.

[0013]

Effects of the Invention As described above, the present invention provides that the perforated part for branching of a cast iron pipe is completely coated with corrosion-resistant metal, including the inner and outer hole edges, without exposing the pipe's bare surface, and that the inner hole edge of the tube Since the metal is in close contact with the corrosion-resistant metal in a type of forge welding state, it prevents water from entering and there is no room for oxygen to exist. Therefore, there is no risk of red rust forming in this area, eliminating concerns about red water being supplied to households.

[Brief explanation of drawings]

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

FIG. 2 is a partially longitudinal front view showing the state of FIG. 1 after construction.

FIG. 3 is a longitudinal sectional front view showing an embodiment of the device of the present invention.

FIG. 4 is a longitudinal sectional side view of the same embodiment as FIG. 3;

FIG. 5 is a longitudinal sectional front view showing the effect of the present invention using (a), (b), and (c).

[Figure 6] A certain state (a) and the next state (a) in the prior art
FIG.

[Explanation of symbols]

1 Sleeve 2 Cast iron pipe 3 Annular packing 4 Construction equipment 11 Top flange 12 Cylindrical part 13 Bottom flange 21 Round hole 22 Outer hole edge 24 Inner hole edge 41 Insertion tube 42 Hook 43 Bending part 44 Notch 45 Rotating handle 46 Saddle 47 Sleeve presser 48 Spring material 50 Male thread part 51 Nut

Claims (3)

[Claims] Claim 1: In a branching perforation of a cast iron pipe, the upper flange of a double-flanged sleeve made of a corrosion-resistant material engages with the circular hole edge on the outer surface of the pipe, the cylindrical portion of the sleeve covers the inner surface of the circular hole, and the sleeve A structure of a perforated part for branching a cast iron pipe, characterized in that the lower flange extends from the edge of the circular hole to the inner surface of the pipe and is crimped. [Claim 2] Drilling a circular hole at a desired position of the cast iron pipe,
The sleeve has a flange attached to the upper surface, a cylindrical part having an outer diameter slightly smaller than the outer diameter of the circular hole, and a length exceeding the pipe thickness, made of a corrosion-resistant material, and the sleeve is inserted into the circular hole to protect the outer surface of the pipe. Lock the upper flange to the hole edge, push the coaxial insertion tube into the sleeve from outside the tube, spread the outer surface of the cylindrical part until it comes into close contact with the inner surface of the circular hole, and then use the bent part of the hook pulled out from inside the insertion tube to A method for constructing a perforated part for branching a cast iron pipe, the method comprising pressing and bending the lower part of the cylindrical part from the hole edge toward the inner surface of the pipe to form a crimped lower flange. [Claim 3] A hook with a bent tip is fitted into a highly rigid insertion tube, and the insertion tube can be raised and lowered and rotated via a spring material provided around the saddle and a sleeve holder fixed to the upper surface of the saddle. A rotary handle is fixed to the upper end of the insertion tube which is freely housed and projects from above the sleeve holder, and a male thread is carved into the upper end of the hook that further projects from the upper end of the insertion tube, and a nut is screwed with the male thread. A device for constructing a perforation for branching a cast iron pipe, wherein the hook is fixed to the upper surface of the rotating handle, and the bent portion below the hook can protrude out of the pipe through a notch provided below the insertion pipe.