JP2003201798A - Cutting diameter-expanding apparatus for renewing existing pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting diameter-expanding apparatus that cuts one portion of the aged and decayed portion of the inner surface of an existing pipe in the ground or the like for renewing. <P>SOLUTION: The cutting diameter-expanding apparatus for renewing an existing pipe composed of a cylindrical cutting tool that is fitted to a hollow support shaft inserted into the existing pipe and has a cutting diameter being slightly smaller than the internal diameter of the existing pipe, a communicating hole that is drilled at the center section of the cutting tool for communicating with the hollow section of the support shaft, a plurality of cylindrical cylinders that are provided from the outer surface of the cutting tool toward the center, a piston that is coaxial with each cylinder and has a collar section sliding on the inner-periphery surface of the cylinder, a spring that is rigged at the upper section of each piston collar section so that a piston shaft section is surrounded, a fixing tool that exists at the upper end of each cylinder and is formed in a cylindrical shape, and has the internal diameter that is fixed coaxially with the cylinder and is the same as the external diameter of the shaft section of the piston, a carbide chip that is stuck to the top section of each piston, and a tie hole that passes through the communicating hole from the bottom section of each cylinder. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting and expanding apparatus for cutting and updating a part of an inner surface of an existing pipe underground. 2. Description of the Related Art Existing pipes such as concrete pipes laid underground deteriorate with time from the inner surface exposed to oxygen. In such a case, the existing pipe may be completely replaced or a new pipe may be laid. However, if only the deteriorated portion of the inner wall of the pipe is repaired, the pipe can be easily and quickly regenerated. There is no major problem in the repair work in the case of a large-diameter existing pipe where workers can enter and work, but in the case of a small-diameter existing pipe where workers cannot enter, work methods and working equipment are required. Become. [0003] As a conventional method for repairing an existing small diameter pipe, a cutting tool having a diameter slightly larger than the inner diameter of the existing pipe is provided at the tip of a support shaft inserted into the existing pipe as shown in FIG. Is attached, and the inside wall of the existing pipe is cut by a certain thickness to expand the diameter by pulling into the existing pipe from the pipe end while rotating the cutting tool. Then, renewal work is performed by coating the cut inner wall with a synthetic resin or the like. [0004] According to the above-mentioned renewal method, a simple and efficient renewal work in which only the deteriorated inner surface of an existing pipe is cut and repaired has been made possible. However, the existing pipe inner surface is not evenly aged and is partly deteriorated, or the existing pipe inner surface is not advanced and the pipe joints are displaced. Since the inner surface is cut from the end of the pipe over the entire span, the cutting operation takes a long time. Further, since many healthy inner wall surfaces are cut, many coating materials are required, which is uneconomical. [0005] Therefore, the present invention provides a cutting and expanding device capable of repairing only an old part of an existing pipe inner wall. [0006] That is, the present invention relates to a cutting and expanding apparatus for cutting and renewing an aged portion of the inner surface of an existing pipe underground, and a hollow support shaft inserted into the existing pipe. A cylindrical cutting tool whose cutting diameter is slightly smaller than the inner diameter of the existing pipe, a communication hole drilled in the center of the cutting tool so that the hollow portion of the support shaft communicates with the cutting tool, A plurality of cylindrical cylinders provided from the outer surface toward the center, a piston having a flange coaxial with each cylinder and sliding on the inner peripheral surface of the cylinder, and a piston shaft on the upper part of each piston flange A spring equipped to surround the cylinder and a fixing tool having a cylindrical shape at the upper end of each cylinder, the inner diameter of which is fixed coaxially with the cylinder and the same as the outer diameter of the shaft of the piston, and fixed to the top of each piston Carbide And a communication hole penetrating from the bottom of each cylinder to the communication hole. [0007] The cutting tool is fixed by screwing the joint portion and the end of the support shaft. The outer diameter of the cutting tool is
It is manufactured with a diameter slightly smaller than the inner diameter of the existing pipe so that it can easily pass through the existing pipe. An injection hole is provided radially from the center of the cutting tool near the cemented carbide tip fixed to the top of the piston, and serves to cool and clean the cemented carbide tip when cutting the inner wall. An O-ring or the like, which is a sealing device, is mounted on the outer periphery of the piston flange so that high-pressure water from the communication hole does not leak to the upper piston shaft. The spring provided so as to surround the piston shaft is set to have a compressive force that is reduced when high-pressure water from the communication hole acts on the piston bottom. [0010] As a work procedure of the renewal work using the present cutting and expanding apparatus, a supporting shaft is inserted into an existing pipe from one manhole or a shaft, and a cutting tool is fixed to the tip of the supporting shaft from the other shaft. Then, the support shaft is pulled out to dispose the cutting tool to a part where the inner wall of the existing pipe is deteriorated. When the cutting tool comes to the aged part, high-pressure water is supplied into the support shaft, enters the communication hole through the communication hole, pushes up the bottom of the piston, and the carbide tip at the tip comes out of the cutting tool. Simultaneously with the supply of the high-pressure water, the cutting tool rotates by giving rotation to the support shaft, and the carbide tip cuts the inner wall of the existing pipe.
When the cutting of the aging part is completed, the supply of high-pressure water is stopped, the piston is pushed back down by the spring,
The carbide tip at the tip enters the cutting tool and finishes cutting.
At the cutting site, the renewal work is completed by coating the synthetic resin or the like with the repair device. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a cutting and expanding device according to the present invention. The outer diameter of the cylindrical cutting tool 1 is manufactured to be slightly smaller than the inner diameter of the existing pipe 13. A communication hole 7 is formed in the center of the cutting tool 1. Cutting tool 1
Eight cylindrical cylinders 2 are equally arranged in the circumferential direction from the outer surface toward the center. In the cylinder 2, a piston 3 having a lower flange portion coaxial with the cylinder 2 and sliding on the inner peripheral surface of the cylinder 2 is provided. A spring 5 is provided above the flange of the piston 3 so as to surround the shaft of the piston 3. Cylinder 2
A cylindrical fixture 11 having the same inner diameter as the outer diameter of the shaft portion of the piston 3 is coaxially fixed to the upper end of the cylinder 2. At the top of the piston 3, a carbide tip 4 is provided with a cutting tool 1.
Is fixed so as to be the same as the outer diameter height. A communication hole 6 is provided from the bottom of the cylinder 2 so as to penetrate the communication hole 7. As described above, the cutting and expanding device is configured. The cylinder 2 installed on the cutting tool 1 is
In the present embodiment, eight locations are illustrated, but the number can be increased or decreased depending on the existing pipe diameter and the material of the existing pipe 13 so that efficient cutting can be performed. The spring 5 presses the flange of the piston 3 toward the center with the fixture 11 fixed to the upper end of the cylinder 2 as a reaction force, and the carbide tip 4 at the top of the piston 3 pops out of the cutting tool 1. There is no. FIG. 2 is a longitudinal sectional view for explaining the cutting tool in detail. The cutting tool 1 includes a joint 9 provided on the cutting tool 1.
Is fixed by screwing the support shaft 8 to the support shaft 8. The cylindrical cutting tool 1 is manufactured with a diameter slightly smaller than the inner diameter of the existing pipe 13 and can freely pass through the existing pipe 13. A communication hole 7 is drilled in the center of the cutting tool 1 to communicate with the hollow portion of the support shaft 8. A cylindrical cylinder 2 is provided from the outer surface of the cutting tool 1 toward the center. In the cylinder 2, a piston 3 having a lower flange portion coaxial with the cylinder 2 and sliding on the inner peripheral surface of the cylinder 2 is provided. An O-ring 12, which is a sealing device, is mounted on the outer periphery of the flange of the piston 3. A spring 5 is provided above the flange of the piston 3 so as to surround the shaft of the piston 3. At the upper end of the cylinder 2, a cylindrical fixture 11 having the same inner diameter as the outer diameter of the shaft of the piston 3 is fixed coaxially with the cylinder 2. A carbide tip 4 is fixed to the top of the piston 3 so as to have the same height as the outer diameter of the cutting tool 1. A communication hole 6 is provided from the bottom of the cylinder 2 so as to penetrate the communication hole 7. An injection port 10 is provided near the carbide tip 4 radially from the center of the cutting tool 1 to cool and clean the carbide tip 4 when cutting the inner wall of the existing pipe 13. Hereinafter, the procedure of the renewal work using the above-mentioned cutting and expanding device will be described. The support shaft 8 is inserted from one shaft to the other shaft, and the cutting tool 1 is fixed to the tip of the inserted support shaft 8. The support shaft 8 is pulled back to the deteriorated portion of the existing pipe 13 which has been inspected in advance by a camera inside the pipe, and the cutting tool 1 is arranged at that position. By supplying high-pressure water into the support shaft 8, the communication hole 7 is connected to the communication hole 6.
The high-pressure water that has entered pushes up the bottom of the piston 3 and brings out the carbide tip 4 at the tip out of the cutting tool 1. Simultaneously with the supply of the high-pressure water, the cutting tool 1 also rotates by giving rotation to the support shaft 8, and the carbide tip 4 that has been in contact with the inner wall of the existing pipe 13 starts cutting. When the cutting to the predetermined diameter is completed, the supply of the high-pressure water is stopped, the piston 3 is pushed down by the spring 5, and the carbide tip 4 at the tip is stored in the cutting tool 1. Then, the support shaft 8 is further pulled back, and the cutting tool 1 is moved to the next cutting point. The cutting site is coated with a constituent resin or the like by a repair device according to the prior art to complete the renewal work. As described above, the cutting and expanding device of the present invention makes it possible to cut and repair only the deteriorated portion of the existing pipe and the misaligned portion of the joint, as in the prior art. Cutting of the inner wall of the entire span of the existing pipe was eliminated, which became very efficient and economical. [0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view illustrating a cutting and expanding device according to the present invention. FIG. 2 is a longitudinal sectional view illustrating a cutting tool in detail. FIG. 3 is a longitudinal sectional view illustrating a conventional cutting and expanding device. [Description of Signs] 1 Cutting tool 2 Cylinder 3 Piston 4 Carbide tip 5 Spring 6 Communication hole 7 Communication hole 8 Support shaft 9 Joint section 10 Injection port 11 Fixture 12 O-ring 13 Existing pipe 14 Conventional cutting tool

Claims (1)

Claims: 1. A cutting diameter expanding device for cutting and renewing an aged portion of an inner surface of an existing pipe underground, wherein the cutting diameter is mounted on a hollow support shaft inserted into the existing pipe. A cylindrical cutting tool slightly smaller than the inner diameter of the existing pipe, a communication hole drilled in the center of the cutting tool so that the hollow portion of the support shaft communicates, and from the outer surface of the cutting tool toward the center. A plurality of cylindrical cylinders provided, a piston coaxial with each cylinder and having a flange sliding on the inner peripheral surface of the cylinder, and an upper portion of each piston flange were provided so as to surround the piston shaft. A spring, a fixing tool having a cylindrical shape at the upper end of each cylinder, the inner diameter of which is fixed coaxially with the cylinder and the same as the outer diameter of the shaft of the piston, and a carbide tip fixed to the top of each piston, Bottom of each cylinder Cutting diameter device for existing pipe update characterized the contact hole penetrating the al the communication hole, to be composed of.