JPH07241708A - Inner face cutting tool for pipe - Google Patents

Abstract

PURPOSE:To provide an inner face cutting tool for pipe which can cuttingly remove rugged parts of the inner face in the vicinity of a pipe end in the condition of remaining no chip and restore the inner face into its smooth condition, even when the rugged parts are formed on the inner face of the pipe by the use of a screwing type cut-off plug. CONSTITUTION:This inner face cutting tool for pipe is constituted so that a columnar body 21 provided with cutting blades 22 for cutting the inner face of a pipe is fitted to the extreme end part of a rod 20 for rotational operation, a disc 23 of which the circumferential part is brought in contact with the inner face of the pipe is fitted to the extreme end side of the columnar body 21, and by drawing out the tool after cutting the inner face of the pipe while rotationally inserting the tool, falling chips in the pipe are simultaneously swept out by the disc 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe inner surface cutting tool.

[0002]

2. Description of the Related Art At present, as a blocking plug for an arbitrary fluid carrying pipe such as a polyethylene gas conduit, a male screw portion 4 is formed on the outer peripheral surface of a cylindrical body 6 as shown in FIG. A seal ring 5 is externally fitted to the outer peripheral surface other than the portion where the male screw portion 4 is formed, the tip end portion of the male screw portion 4 is formed in a tapered shape, and a rotation operation portion 6a is provided at the rear end portion. Things have been proposed. In other words, the above-mentioned shut-off plug, by pressing the shut-off plug into the pipe while turning,
While avoiding leakage of internal fluid by the seal ring 5,
The male threaded portion 4 is engaged with the inner surface of the pipe to be inserted into the pipe, and is characterized in that the pipe end can be closed without stopping the supply of fluid on the upstream side of the pipe.

[0003]

Generally, it is desirable to close the pipe with a shut-off plug and then fuse the pipe end with a resin plug to prevent leakage. When the above blocking plug is used, a female screw portion is formed by the biting of the male screw portion on the inner surface of the pipe after the blocking plug is inserted. There is a possibility that the plug end cannot be reliably fused with the tube end formed with.

Therefore, it is conceivable to cut the irregularities on the inner surface of the pipe end after inserting the blocking plug, but the chips remain in the pipe and the plug plug cannot be reliably fused. There is a risk.

The object of the present invention is to eliminate the above-mentioned drawbacks.

[0006]

In order to achieve the above-mentioned object, a characteristic construction of an inner surface cutting tool for a pipe according to the present invention comprises a cutting blade for cutting the inner surface of the pipe at a tip end portion of a rod for rotary operation. A cylindrical body is attached, and a disk whose peripheral portion abuts or almost abuts the inner surface of the pipe in a state of being inserted into the pipe is attached to the tip end side of the cylindrical body. Moreover,
It is preferable that at least the peripheral portion of the disk is made of an elastic body.

[0007]

In other words, since a disk whose peripheral portion is in contact with the inner surface of the pipe is attached to the tip end side of the columnar body equipped with the cutting blade, and the columnar body is attached to the tip end part of the rotation operation rod, When the columnar body is inserted into the pipe from the end of the pipe while rotating the operating rod, the irregularities that are the female threads formed on the inner surface of the pipe are cut to form a smooth surface, and the chips are inside the pipe on the pipe end side of the disc. Accumulated in. Such a cutting process
After performing at least the length of the plug stopper, if the rotary operation rod is retracted and the cylindrical body is pulled out from the inside of the tube, the chips accumulated in the tube are swept out of the tube by the disk. At this time, even if there is a slight gap between the disk and the inner surface of the pipe, large chips that hinder the fusion of the plug plug are reliably removed.

Further, if the disk has at least its peripheral portion made of an elastic body, even if the disk is configured to have a diameter that surely contacts the inner surface of the pipe expanded by cutting,
The disc can be easily inserted into the small diameter pipe before cutting, and the chips accumulated in the pipe can be swept out of the pipe more reliably.

[0009]

Therefore, according to the present invention, even if the inner surface of the pipe is formed to be uneven by using the screw-in type shut-off plug, the uneven portion is left on the inner surface near the end of the pipe without leaving chips. Since it can be removed by cutting and restored to a smooth state, the plug stopper can be reliably fused without any fluid leakage.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. The pipe end blockage treatment method of the branch pipe 2 connected to the fluid transport main pipe 1 which is a polyethylene gas pipe buried in the ground through the saddle portion 1a is performed by a construction pit (Fig. (Not shown) and the internal pressure of the branch pipe 2 is set to a low pressure state, and then the procedure shown in FIGS. 1 and 2 is performed.

First, as shown in FIG. 1A, a branch pipe 2
Is determined on the lower side of the gas flow direction, and the squeeze-off tool 3 cuts off the flow of gas at a point on the upper side of the gas flow direction, that is, a root side than the planned cut point, and the branch pipe 2 is Cut at the planned cutting point. here,
The squeeze-off tool 3 is a tool for temporarily crushing the gas conduit in a recoverable manner by tightening the gas conduit so as to interrupt the flow of gas.

Next, as shown in FIG. 1B, a cylindrical stopper 9 having a male screw portion 4 formed around the front end side and a seal ring 5 attached around the rear end side is attached to the branch pipe. The squeeze-off portion 2 from the cut end portion 2b of 2 using an operation tool described later.
Pivot and insert until just before a. In other words, the body of the stopper 9 is
The male screw portion 4 advances in the pipe while being bitten by the inner wall portion of the polyethylene gas conduit.

After that, as shown in FIG. 2 (a), the squeeze off is released, and the stopper 9 is further swung into the base side of the branch pipe 2, and the stopper 9 is inserted from the insertion position. The remaining portion of the branch pipe 2 on the front side is cut.

Finally, as shown in FIG. 2B, after the internal thread portion formed on the inner peripheral surface in the vicinity of the new cutting end portion 2c is removed by using the inner surface cutting tool of the pipe according to the present invention. 2A, a resin plug plug 7 is fitted from the cut end 2c to fuse the joint, or the closing cap 8 is cut to the cut end as shown in FIG. 2C. Two
It is fitted onto c and is fused to the branch pipe 2 to close the cut portion. Then, the squeeze-off tool 3 and the like are taken out of the construction pit, and then the construction pit is backfilled to complete the closing process.

Next, the stopper 9 will be described in detail. As shown in FIGS. 1B to 2C, the stopper 9
Is formed by forming a male screw portion 4 on the outer peripheral surface on the tip end side of the columnar body 6 and fitting a seal ring 5 on the rear end side of the columnar body 4 so as to taper the tip end portion of the columnar body 6. In addition to being formed into a shape, a rotation operation portion 6a is provided at the rear end portion, and a recess 6b is formed between the male screw portion 4 and the outer fitting portion of the seal ring 5.

That is, by forming the tip of the male screw portion 4 in a tapered shape, even if the female screw portion is not formed on the inner peripheral surface of the branch pipe 2, the female screw portion is formed on the inner peripheral surface of the branch pipe 2 by itself. It is possible to proceed while forming, and by accommodating the chips generated at that time in the recess 6b, the chips are sandwiched between the seal ring 5 and the inner peripheral surface of the branch pipe 2 to form a seal. It is to avoid the deterioration of the sex.

The operation tool 10 of the stopper 9 will be described. As shown in FIG. 3 and FIG. 4, the operation tool 10 includes a radially-divided outer sandwiching body 11 and 12 capable of embracing the branch pipe 2, and retaining inside the outer sandwiching bodies 11 and 12. A tubular body 14 having a locking portion 14a to be locked, and a fitting hole 14b for fitting the holding member 13 on the end, and a through hole formed in the center of the holding member 13. 13a and a rotary operation rod 15 which is slidable back and forth in the axial direction.

Each of the outer sandwiching bodies 11 and 12 has a shape in which a short, substantially cylindrical body which can be fitted onto the branch pipe 2 is radially divided into two parts, and they are arranged in an integrated state before the division. One of the facing portions is pivotally connected by a pivot member 16, and the other is releasably fastened by a fastener 17. After the fastening by the fastener 17 is released to open the outer sandwiching bodies 11, 12 and then the outer sandwiching bodies 11, 12 are externally fitted to the branch pipe 2 and then closed, the fastener 17 By performing the conclusion by
The outer sandwiching bodies 11 and 12 can hold and hold the branch pipe 2.

After the tubular main body 14 is externally fitted from the cut end portion of the branch pipe 2, the outer holding bodies 11 and 12 are arranged so that the external fitting portions of the tubular main body 14 are overlapped with each other from above. The outer holding body 1 by holding and holding 2
Engaging the engaging portions 11a and 12a formed on the inner side surfaces of 1 and 12 with the engaging portion 14a prevents the tubular body 14 from coming off.

The rotary operation part 6a formed at the rear end of the stopper 9 is a concave part having a rectangular shape when viewed from the front.
The rectangular tip portion 15a of No. 5 is fitted into the concave portion and is connected, and the state described above, that is, the branch pipe 2 and the stopper 9
In a state where the axes of the two are matched, the rotation operation rod 15 is pressed and rotated to rotate the stopper 9.

The rectangular tip portion 15 of the rotary operating rod 15
Balls which are urged outward by springs are arranged on the four side walls of a, while small-diameter holes cb into which the balls are fitted are formed on the inner wall surface of the recess forming the rotary operation part 6a. Is configured to prevent the rotation operating rod 15 and the stopper 9 from coming off.

Next, the inner surface cutting tool for a pipe according to the present invention will be described in detail. As shown in FIGS. 5 (a) and 5 (b), the inner surface cutting tool for a pipe is provided with a reamer as a columnar body 21 having a cutting blade 22 for cutting the inner surface of the pipe, which is attached to the tip portion of the rotary operation rod 20. A disk 23 having a peripheral portion in contact with the inner surface of the branch pipe 2 is attached to the tip side of the reamer.

The cylindrical body 21 is externally fitted to the tip end portion of the rotation operation rod 20 with its axis aligned, and the disc 23 is attached to the tip end side thereof via a spacer 24. From the outside, the rotary operation rod 20
Is connected to the tip end of the rod with a bolt 25, and a pin 26 for preventing slippage is formed so as to extend over the rotation operating rod 20 and the columnar body 21. The disk 23 has a ring-shaped body 23b made of rubber or resin as an elastic body on the outer periphery of a disk body 23a made of metal, and the diameter of the disk 23 contacts the inner surface of the pipe after being cut by the reamer. It is composed of. At the rear end of the rotary operation rod 20, an operation portion 2 having a rectangular cross section is provided.
5 is formed, and an operation handle (not shown) is inserted into the operation portion 25 to rotate the operation portion.

For the inner surface cutting tool of the pipe, the axis of the columnar body 21 having the branch pipe 2 and the cutting blade 22 is aligned by using the same operation tool 10 'as the operation tool 10 described above. In this state, the inner surface of the branch pipe 2 is cut by pressing and rotating the rotation operation rod 20. That is, when the columnar body 21 is inserted into the tube from the end of the tube while rotating the rotating operation rod 20, (at this time, the disk 23 is inserted while elastically deforming the periphery), a female screw formed on the inner surface of the tube is formed. The unevenness, which is a portion, is cut to form a smooth surface, and chips are accumulated in the tube on the tube end side of the disk 23. After performing such a cutting step for at least the length of the plug, if the rod for rotation operation is retracted and the cylindrical body 21 is pulled out from the inside of the pipe, the chips accumulated in the pipe are accompanied by the above. It is swept out of the tube by the disk 23.

Here, a reamer can be generally used as the columnar body 21 provided with the cutting blade 22, but the invention is not limited to this, and the columnar body 21 is provided with the cutting blade 22 to cut the inner surface of the pipe. Anything is optional.

Further, although the annular body 23b, which is an elastic body, is arranged on the outer peripheral portion of the disk 23, and the diameter of the annular body 23b abuts the inner surface of the pipe after being cut by the reamer has been described. Even if the whole disk 23 is made of an elastic body, the same effect can be obtained. Further, even if the diameter is slightly smaller than the pipe diameter after being cut, the fusion of the plug stopper is hindered. There is no problem as long as large chips can be reliably removed.

In the above-mentioned embodiment, the case where the method is used for the pipe end blockage treatment method of the branch pipe 2 which is connected to the fluid conveying main pipe 1 which is a polyethylene gas pipe through the saddle portion 1a, is used. The present invention is not limited to this, and may be used to shut off the fluid transfer main pipe 1 or may be used to shut off resin pipes other than the polyethylene gas pipe. Furthermore, the present invention is not limited to the one used for the gas conduit, but can be applied to other fluid carrying pipes.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is an explanatory view of a method for treating the end of a polyethylene pipe.

FIG. 2 is an explanatory view of a method for treating the end of a polyethylene pipe.

FIG. 3 is a vertical cross-sectional view of the main part

FIG. 4 is a cross-sectional view of the main part

FIG. 5 is a cross-sectional view of the main part

[Explanation of symbols]

 20 Rotating Operation Rod 21 Cylindrical Body 22 Cutting Blade 23 Disk

Claims (2)

[Claims] 1. A distal end portion of a rotating operation rod (20),
A cylindrical body (2) equipped with a cutting blade (22) for cutting the inner surface of the pipe.
1) is attached, and a disk (23) is attached to the tip end side of the columnar body (21) so that its peripheral portion abuts or almost abuts the inner surface of the tube in a state of being inserted into the tube. Internal cutting tool. 2. The inner surface cutting tool for a pipe according to claim 1, wherein at least a peripheral portion of the disk (23) is made of an elastic material.