JP2001241567A - Pipe cutting apparatus for existing pipework - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe cutting apparatus for existing pipework which makes it possible to remove the planned range of the existing pipework for destruction safely and efficiently under such conditions that no damage to the newly constructed pipework is likely to occur. SOLUTION: In the pipe cutting apparatus C for the existing pipework B which splits the planned range D for destruction preliminary cut out along the pipe periphery at the ends spaced longitudinally in the existing pipe B of hard material, the pipe cutting apparatus for the existing pipework comprising: pressing members 1a, 1b, upon which rotary cutters to be pressed into contact with the periphery of the existing pipe B are mounted rotatably about the axis approximately perpendicular to the pipe axis of the existing pipe B, which are installed freely displaceable relatively in radial direction, and a displacement control section 3 which controls the displacements in radial direction of the pressing members 1a, 1b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an existing pipe splitting device for splitting a crushed area in which both ends of a hard existing pipe in the longitudinal direction of the pipe are cut in advance along the pipe circumferential direction. .

[0002]

2. Description of the Related Art For example, when it becomes necessary to connect a branch pipe to a new pipe inserted inside a hard existing pipe, the existing pipe at a location where the branch pipe is to be connected is spread over a predetermined area to be crushed. Conventionally, there is no suitable device for splitting existing pipes in the area to be crushed, which has been cut in advance along the pipe circumferential direction at both ends in the pipe longitudinal direction. The pipe wall of the existing pipe in the planned area is broken by the impact force to crush the existing pipe in the crushing area.

[0003]

For this reason, the pipe wall of the existing pipe in the area to be crushed is apt to be scattered as a large number of irregularly shaped pieces, and it takes time and effort to collect those pieces. However, there is a disadvantage that the operation is also dangerous. In addition, there is a disadvantage that the fragments are easily impacted against the outer peripheral surface of the new pipe to easily damage the new pipe. Therefore, the present invention has been made in view of the above-mentioned circumstances, and has an object to safely and efficiently remove an existing pipe in a crushing area in a state where the new pipe is hardly damaged. I do.

[0004]

As shown in FIGS. 1 to 3, the present invention is characterized in that a hard existing pipe B is provided.
The crushing range D, in which both ends of the pipe in the longitudinal direction of the pipe are cut in advance along the pipe circumferential direction, is pressed against the outer peripheral surface of the existing pipe B in the pipe splitting device C for the existing pipe B. Pressing members 1a and 1b provided with the rotary blade 4 rotatably about an axis substantially perpendicular to the tube axis direction of the existing tube B are provided so as to be relatively movable in the tube radial direction, and the pressing members 1a and 1b are provided. The point is that a movement operation unit 3 for performing relative movement operation in the pipe diameter direction is provided. [Operation] The pressing member is moved in the pipe axis direction while the rotating blade is pressed against the outer peripheral surface of the existing pipe by moving the pressing member relatively to the existing pipe by the moving operation section, and both ends in the pipe longitudinal direction. By rolling the rotary blade along the pipe axis in the crushing range of the existing pipe that has been cut in advance along the pipe circumferential direction, the rotary blade is crushed on the pipe wall while crushing the outer peripheral part of the pipe wall. By making a cut along the pipe axis until cracks that reach the inside and outside of the pipe wall are formed along the rolling trace of the rotary blade, the existing pipe wall in the crushing area is circumferentially cut. Can be divided into a plurality of strip-shaped fragments. [Effect] Therefore, without applying a large impact force to the existing pipe, it is possible to efficiently apply the force to cause the rotary blade to bite into the pipe wall, and to split the pipe wall of the existing pipe in the range of crushing. Fragments of the wall are hardly scattered, the pipe wall in the area to be crushed can be safely removed, and even if the new pipe is inserted inside the existing pipe, the risk of damaging the new pipe can be reduced. Further, since the pipe wall of the existing pipe in the area to be crushed can be divided into a plurality of strip-shaped pieces in the circumferential direction, the pieces can be easily removed, and the existing pipe in the area to be crushed can be efficiently removed. In addition, since the rotating blade is rolled along the outer peripheral surface of the existing pipe to form a split groove in the existing pipe,
Roll the rotary blade according to the length of the crushing range,
The tube wall in the area to be crushed can be efficiently divided into strip-shaped fragments.

As shown in FIG. 4, the feature of the invention according to claim 2 is that, as the rotary blade 4 bites into the tube wall, the rotary blade 4 comes into contact with the outer surface of the tube wall, and The present invention is characterized in that a cut-in control section 7 for controlling the cut-in amount to the wall is provided in the existing pipe splitting device C according to the first aspect. [Operation] As the rotary blade bites into the tube wall, the biting restricting portion comes into contact with the outer surface of the tube wall, and the amount of biting of the rotary blade into the tube wall is regulated. [Effect] Therefore, the amount of biting of the rotary blade into the pipe wall can be regulated in a timely manner, and the risk of damaging the new pipe inserted inside the existing pipe can be reduced.

FIG.
As shown in FIG. 2, a plurality of the rotary blades 4 are provided on the pressing members 1a and 1b so as to roll along a common imaginary line substantially parallel to the pipe axis direction of the existing pipe B. On the point. [Operation] A plurality of rotary blades mounted on the pressing member are rolled along a common virtual line segment substantially parallel to the pipe axis direction to form a split groove along the pipe axis direction of the existing pipe. [Effect] For this reason, even when the length of the crushing area in the tube axis direction is long, a plurality of rotary blades roll along a common imaginary line, thereby determining the traveling direction of the split groove formed by the rotary blade. This makes it possible to efficiently form a stable split groove along the pipe axis direction. In addition, by moving the pressing member in a state where the rotary blade on the rear side is rolled on the rolling trace of the rotary blade on the distal end side in the moving direction, a deep split groove can be efficiently formed.

[0007] The characteristic structure of the invention according to claim 4 is shown in Figs.
As shown in FIG. 2, a plurality of the pressing members are arranged freely in the circumferential direction of the tube. [Function] A plurality of pressing members can be attached to an existing pipe so that the rotating blades attached to the pressing members sandwich the pipe wall of the existing pipe from a plurality of pipe radial directions along the pipe longitudinal direction, and at a time, in a pipe circumferential direction. Can be divided into a plurality of strip-shaped pieces. [Effect] Therefore, it is possible to efficiently split the existing pipe in the area to be crushed into a plurality of strip-shaped pieces and remove it.

[0008] As described above, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the accompanying drawings.

[0009]

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

FIGS. 1 to 4 show the positions of both ends in the longitudinal direction of an existing pipe made of cast iron (an example of a hard existing pipe) into which a new pipe A made of polyethylene resin for gas supply is inserted. 1 shows an existing pipe splitting device C according to the present invention for removing an existing pipe B portion of a planned crushing range D cut in advance along a circumferential direction. As shown in FIGS. 1 to 3, an existing pipe splitting device C is
A pair of upper and lower pressing members 1a and 1b, four support columns 2 that support the pair of pressing members 1a and 1b so as to be relatively movable in the pipe radial direction with the existing pipe B interposed therebetween, and a hydraulic cylinder 8 that expands and contracts. A moving operation unit 3 for relatively moving the pair of pressing members 1a and 1b in the approaching direction is provided. A rotary blade 4 for pressing against the outer peripheral surface of the existing pipe B is attached to each of the pressing members 1a and 1b so as to be rotatable around an axis substantially perpendicular to the pipe axis direction of the existing pipe B. The pipe splitting device C is provided such that the length along the pipe longitudinal direction is shorter than the length of the existing pipe B in the crushing scheduled range D.

The pressing members 1a and 1b are held in the longitudinal direction of the tube so that the rotating blade 4 attached to the pressing members 1a and 1b sandwiches the tube wall of the existing tube B from the tube diameter direction along the tube longitudinal direction. The pair of pressing members 1a and 1b are relatively moved in the approaching direction by the moving operation unit 3 by attaching both end positions to the existing pipe B portion of the crushing expected range D which has been cut in advance along the pipe circumferential direction with a chain cutter or the like. Then, while pressing the rotary blade 4 against the outer peripheral surface of the existing pipe B, the pair of pressing members 1a and 1b are moved in the pipe axis direction, and the rotary blade 4 is rolled along the pipe axis direction, thereby making the existing blade B roll. Crush the outer circumference of the pipe B
The groove 18 is formed along the pipe axis direction.

In each of the pressing members 1a and 1b, a groove 5 substantially parallel to the pipe axis direction is formed at an intermediate portion thereof in a state where the pressing member 1a and 1b are mounted on the existing pipe B. Rotary blade 4
Are mounted so as to roll along a common virtual line segment substantially parallel to the tube axis direction of the existing tube B. Upper pressing member 1a
Is supported movably up and down along the support column 2 so as to be movable in the pipe radial direction of the existing pipe B, and the lower pressing member 1
“b” is detachably fixed to the lower end of the support column 2. The lower pressing member 1b has through holes formed at its four corners,
The support column 2 is inserted there, and is fixed with a screw 12 having a male screw corresponding to a female screw provided on the inner periphery of the lower end of the support column 2.

Each of the rotary blades 4 is supported from both left and right sides of the groove 5 so as to be rotatable around an axis substantially perpendicular to the pipe axis direction of the existing pipe B. Further, as the rotary blade 4 bites into the tube wall, it comes into contact with the outer surface of the tube wall, and the biting restricting portion 7 having the contact surface 6 for restricting the amount of biting of the rotary blade 4 into the tube wall is formed by each pressing member 1a. , 1b, the blade portion 4a of the rotary blade is made to protrude from the contact surface 6 with a thickness of about 80% of the thickness of the tube wall, and the blade portion 4a penetrates the tube wall of the existing tube B. I try not to cut it.

The moving operation section 3 fixes the hydraulic cylinder 8 to a fixing plate 17 fixed to the upper end of the support column 2, connects the piston 9 to the upper pressing member 1a, and moves the piston 9 up and down. The upper pressing member 1a to the lower pressing member 1
b. The hydraulic cylinder 8 is provided such that the piston 9 is in contact with the upper part of the guide groove of the pressing member 1a, and the pair of pressing members 1a and 1b relatively move in the approaching direction by the extension operation of the piston 9. Have been.

Hereinafter, a method of splitting the existing pipe B portion in the crushing scheduled area D using the existing pipe splitting device C will be described. An existing pipe splitting device C from which the lower pressing member 1b has been removed is laid so that the existing pipe B enters between the supporting columns 2, and then the lower pressing member 1b is attached to the lower end of the supporting column 2. As shown in FIG. 2, as shown in FIG. 2, a pipe cutting device C for the existing pipe is installed so as to sandwich the existing pipe B from above and below in the pipe diameter direction by rotating blades 4 provided on the pair of pressing members 1 a and 1 b. The blade 4 is brought into contact with the pipe wall. Next, by driving the hydraulic cylinder 8, the pair of pressing members 1a, 1b are moved toward each other in the direction of approaching each other, and while the rotary blade 4 is pressed against the pipe wall, the splitting device C for the existing pipe is reciprocated in the pipe axis direction. Then, by rotating the rotary blade 4 along the pipe axis direction, while crushing the outer peripheral surface of the pipe wall,
The rotary blade 4 is cut into the tube wall. As shown in FIG. 4A, the amount of biting of the rotary blade 4 into the pipe wall is controlled so that the contact surface 6 of the biting control section 7 contacts the outer surface of the pipe wall and does not damage the new pipe A. In addition, crack 1
Until 9 is generated along the rolling trace of the rotary blade 4, the existing pipe B
A groove 18 is formed along the pipe axis direction, and as shown in FIG. 4 (b), the pipe wall of the crushing scheduled range D is divided into two half-tubular strip-shaped pieces 29 in the circumferential direction. I do.

[Second Embodiment] FIGS. 5 and 6 show another embodiment of an existing pipe splitting device C, in which a pair of upper and lower axial pressing members 1a and 1b and a pair of pressing members 1a and 1b are arranged. A support member 10 having a downward U-shaped cross section for supporting the existing pipe B so as to be relatively movable in the pipe radial direction, and a moving operation unit 11 for relatively moving the pair of pressing members 1a and 1b in the proximity direction. Are provided. On each of the pressing members 1a and 1b, a rotary blade 4 for pressing against the outer peripheral surface of the existing pipe B is attached so as to be rotatable around an axis substantially perpendicular to the pipe axis direction of the existing pipe B. The upper pressing member 1a is an existing pipe B
Both ends of the lower pressing member 1b are supported by the supporting member 10 so that the both ends thereof are vertically slidably movable in the guide groove 13 of the supporting member 10 so as to be movable in the pipe radial direction. It is detachably fixed.

The lower pressing member 1b is formed in the shape of a shaft having male threads at both ends thereof, and has a through hole at one lower end of the support member 10 and a hinge at the other lower end. A through hole is provided in a swinging plate 23 that is swingably supported outwardly at 22, and the pressing member 1b is inserted into the inside of the support member 10 in a state where the swinging plate 23 is swung outwardly. These male threads are inserted into each through hole and fixed with nuts 24. The moving operation unit 11 rotatably supports a screw shaft 26 interlocking with a rotation operation handle 25 on the upper surface of the support member 10 via a worm gear 14, and a wedge member on a top member 27 screwed to the screw shaft 26. 15 is fixed, and the screw shaft 26 is rotated by the rotation operation of the rotation operation handle 25,
By moving the top member 27 together with the wedge member 15, the pressed portion 16 fixed to the upper pressing member 1 a is pushed down on the wedge surface 28 to form a pair of pressing members 1 a,
1b are provided so as to relatively move in directions approaching each other.

Hereinafter, a method of splitting the existing pipe B portion in the crushing scheduled area D using the existing pipe splitting device C will be described. After the existing pipe splitting device C from which the lower pressing member 1b is removed is straddled so that the existing pipe B enters between the supporting members 10, the pressing member 1b is fixed to the supporting member 10, As shown in FIG. 7A, a pair of pressing members 1a, 1
The existing pipe splitting device C is mounted so as to sandwich the existing pipe B from above and below in the radial direction of the pipe with the rotary blade 4 provided at b, and the rotary blade 4 is brought into contact with the pipe wall. Next, by rotating the rotating operation handle 25, the pair of pressing members 1a and 1b are moved toward each other in a direction approaching each other, and while pressing the rotary blade 4 against the outer peripheral surface of the existing pipe B, the existing pipe separating device C Is reciprocated in the pipe axis direction, and the rotary blade 4 is rolled along the pipe axis direction, so as to crush the outer peripheral surface of the pipe wall, as shown in FIG. Make it dig into the wall less than its thickness.
Then, as shown in FIG.
Until the occurrence along the rolling trace of the rotary blade 4, a split groove 18 is formed in the existing pipe B along the pipe axis direction, and the crushing range D
Is divided into two half-tubular strips 29 in the circumferential direction.

[Another Embodiment] Another embodiment will be described below. <1> The method of moving the pressing member in parallel to the pipe axis direction of the existing pipe is not limited to the manual method described in the above embodiment, and may be, for example, automatically moved via a driving device or the like. good. <2> The pressing member is not limited to the pair of two members described in the above embodiment, but may be, for example, a member of three or more members. <3> The number of the rotary blades is not limited to the number described in the above embodiment, but may be any number as needed. <4> The method of relatively moving the pressing member is not limited to the method using the hydraulic cylinder and the wedge member described in the above embodiment, but may be any method as long as the pressing member can be relatively moved. <5> The bite restricting portion for restricting the amount of biting of the rotary blade into the tube wall may be, for example, a rotary blade that contacts the side surface of the rotary blade with the outer surface of the tube wall as the rotary blade bites into the tube wall. May be formed by forming an abutment surface for controlling the amount of bite into the tube wall.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a pipe splitting device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a pipe splitting device according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of a pipe splitting device according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of a pipe splitting device according to the first embodiment of the present invention.

FIG. 5 is an explanatory view of a pipe splitting device according to a second embodiment of the present invention.

FIG. 6 is an explanatory diagram of a pipe splitting device according to a second embodiment of the present invention.

FIG. 7 is an explanatory view of a pipe splitting device according to a second embodiment of the present invention.

[Explanation of symbols]

 1a, 1b Pressing member 2 Support column 3 Moving operation unit 4 Rotating blade B Existing pipe 18 Split groove

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Mae 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Masahiro Yamada Hirano-cho, Chuo-ku, Osaka-shi, Osaka Chome 1-2, Osaka Gas Co., Ltd.

Claims (4)

[Claims] 1. An existing pipe splitting device for splitting a predetermined crushing range in which both ends of a hard existing pipe in a pipe longitudinal direction are cut in advance along a pipe circumferential direction, wherein the existing pipe is provided. A pressing member provided with a rotary blade for pressing against the outer peripheral surface of the existing pipe rotatably about an axis substantially perpendicular to the pipe axis direction of the existing pipe is provided so as to be relatively movable in the pipe radial direction, and the pressing member is provided in the pipe radial direction. An existing pipe splitting device provided with a moving operation unit for performing a relative moving operation. 2. A biting restricting portion for restricting an amount of biting of the rotary blade into the pipe wall by contacting the outer surface of the pipe wall as the rotary blade bites into the pipe wall.
An existing pipe splitting device as described. 3. A plurality of the rotary blades are provided on the pressing member.
3. The existing pipe splitting device according to claim 1, wherein the existing pipe is provided so as to roll along a common virtual line segment that is substantially parallel to a pipe axis direction of the existing pipe. 4. 4. The existing pipe splitting device according to claim 1, wherein a plurality of the pressing members are arranged freely in a pipe circumferential direction.