JPH069407B2 - Tube straightening method for underground pipes - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a pipe straightening method for an underground pipe that is laid underground, for example, to draw in a telecommunication cable. Then, the present invention relates to a pipe straightening method for an underground pipe to repair the cable so that it can be pulled in.

[Prior art]

As shown in FIG. 3, this type of underground pipeline A usually has a diameter of 7 mm below the road, such as between manholes B and C.
It is made by laying a plurality of pipes of about 15 cm in a gathered and aligned form. At the time of the first laying construction, in the future,
An extra empty pipeline, which is expected to be expanded, is laid at the same time, and thereafter, the cable to be expanded has a form in which an arbitrary pipeline which is the empty pipeline is selected and drawn. By the way, such underground pipes may break, break away, flatten, bend sharply, or have holes in the pipe body due to fluctuations in the ground or the load of vehicles passing on the road during the years after installation. However, there is a case where a defect phenomenon such as intrusion of foreign matter or corrosion occurs, which causes a problem that a new cable is hindered. When repairing such a defective pipe, for example, when repairing a defective portion such as breakage, separation, flatness, etc., the repair method using the cylinder device D as shown in FIGS. 3 and 4 is the applicant. Have been proposed by. This cylinder device D
Is configured as follows. That is, a cone-shaped expanding head 1 is provided at the tip, and a pulling wire 2 is connected to the front end of the expanding head 1. A hammer rod 3 is connected to the rear end of the expanding head 1 and the hammer rod 3 is inserted into the cylinder 4. A hammer head 5 is provided at the rear end of the hammer rod 3, and the hammer head 5 and the cylinder are
A compression coil spring 6 is interposed between the front end wall 4 and the front end wall 4. A piston 7 is slidably fitted into the cylinder 4, and compressed air is supplied from the rear end of the cylinder 4 into the cylinder 4 through a pressure-resistant hose 8 from a compressor 9. There is. A rubber collar 10 for holding the cylinder 4 in the central position in the underground conduit A is attached to the outer periphery of the rear portion of the cylinder 4. Then, in order to insert the cylinder device D configured as described above into the underground pipeline A to be repaired, between the manholes B and C which are one section of the underground pipeline A, the above-mentioned pulling from one manhole B is performed. Insert the wire 2 into the other manhole C. Then, when the wire 2 is taken out from the manhole C on the opposite side, wound up by a winch 11 or the like and pulled, the cylinder device D is introduced into the underground conduit A from the manhole B. When the cylinder device D reaches a defective portion X shown in FIG. 3 (in the drawing, an internal bulging portion is shown, the same applies to breakage, detachment, misalignment, flatness, etc.).
Impinges on the defective portion X and prevents the progress. At this time, compressed air is supplied from the compressor 9 into the cylinder 4 via the pressure-resistant hose 8, and the piston 7 strikes the hammer head 5. The impact force of this tapping is added to the expanding head 1,
Push the defective point X outward to expand it. By repeating this tapping, the cylinder device D corrects the defective portion X and corrects the underground conduit A.
The new cable can be pulled in after passing through.

[Problems to be Solved by the Invention]

However, the above-mentioned conventionally known cylinder device D requires a predetermined length because it is tapped by the piston, and therefore, when the cylinder device D can pass through the pipeline while correcting the defective portion of the underground pipeline A. Can be used, but underground pipe A
If there is a curved pipe portion inside, there is a problem that the cylinder device D is stuck and the forward movement is blocked, so that it cannot be used.

[Means for solving problems]

Therefore, the present invention uses the above-mentioned conventional cylinder device to provide a straightening body having a length at least shorter than that of the cylinder device and having an outer diameter substantially equal to the inner diameter of the conduit in the conduit on the front side of the expanding head. Multiple straight lines are arranged, and these straightening bodies are advanced by the tapping action from the cylinder device via the diameter expansion head to correct the deformation of the pipeline, and it is possible to straighten straight pipes as well as curved pipes. It is characterized by.

【Example】

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the first embodiment of the present invention shown in FIG. 1, an underground conduit A similar to the above-mentioned conventional example has a curved portion Aa for bypassing an obstacle E during installation. A defective portion X (internal bulging portion in the drawing) is generated in the curved portion Aa, and the curvature of the curved portion Aa is such that the cylinder device D, which is similar to the curved pipe portion of the conventional example, cannot pass through. There is. In the cylinder device D, a steel ball 20 having an outer diameter substantially equal to the inner diameter of the underground conduit A in the conduit on the front side of the expanding head 1 and serving as a correction body is provided.
Are arranged so as to be inserted into the pulling wire 2. A return wire 2a is connected to the rear end of the cylinder 4 of the cylinder device D. In the first embodiment configured as described above, when repairing the defective portion X, a large number of steel balls 20 are inserted through the towing wire 2 in front of the expanding head 1 of the cylinder device D. The cylinder device D is installed and the expansion head 1 of the piston 7 is expanded.
The steel ball 20 is sequentially pushed by the expanding head 1 by a tapping action against. When each steel ball 20 passes through the curved portion Aa, the defective portion X is corrected and repaired. When the expanding head 1 of the cylinder device D contacts the curved portion Aa and the cylinder device D cannot move forward, the tapping action of the piston 7 is stopped, the winding of the towing wire 2 is loosened, and the cylinder 2 is returned by the returning wire 2a. The device D and the steel ball 20 are retracted and discharged from the underground pipeline A. If the defective portion X is not sufficiently corrected by the repair work from one direction of the underground pipe A, the repair work can be surely corrected by performing the same repair work from the other direction of the underground pipe A. Further, even when the underground pipeline A is a straight pipe, the defective portion X can be corrected with the steel ball 20 provided in front of the cylinder device D or only by the cylinder device D. In the second embodiment of the present invention shown in FIG. 2, instead of the steel ball 20 in the first embodiment, only the length is longer than the steel ball 20 and the length is shorter than the cylinder device D. The structure is the same as that of the first embodiment except that the oblong body (rod-shaped body) 21 is arranged. Also in this second embodiment, as in the first embodiment, the oblong body 21 pushed by the cylinder device D corrects the defective portion X when passing through the curved portion Aa. In, the curvature and the flatness can be corrected by the ellipsoid 21. In the first and second embodiments, the number of the steel balls 20 and the oblong bodies 21 serving as the correction body may be increased or decreased depending on the length of the curved portion Aa. The shape is not limited to a sphere or an ellipse, but may be another shape.

【The invention's effect】

As described above, according to the pipe body straightening method for an underground pipe according to the present invention, a plurality of straightening bodies having a length shorter than that of the cylinder device are arranged in the pipe line on the front side of the cylinder device, and the cylinder body is installed. Since it is pushed by the tapping action of the device, it is possible to easily repair not only the straight pipe part, but also the defective part generated in the curved part that the cylinder device cannot pass and is difficult to correct. Further, the curvature can be corrected along with the diameter of the pipe at a sharp bend in the pipe, and the pipe can be widened at the bend. Further, it is possible to correct a portion which has been difficult to correct in the past without providing a special device with a simple structure, which is extremely useful in practice.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a first embodiment of the present invention, and FIG.
FIG. 3 is a vertical sectional side view showing the second embodiment, FIG. 3 is a vertical sectional side view showing a conventional example, and FIG. 1… Expanding head, 2… Traction wire, 2a… Return wire, 3… Hammer rod, 4… Cylinder, 5… Hammer head, 6… Compression coil spring, 7… Piston, 8… Pressure hose, 9… Compressor , 10 ... Rubber color, 11 ... Winches, 20 ... Steel balls, 21 ... Oval, A ... Underground pipe, Aa
… Curved section, B, C… Manhole, D… Cylinder device, E
… Obstacles, X… defective parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayuki Kamo 1-1-6 Uchisaiwai-cho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Fumio Yabuhara 1-1-6 Uchiyuki-cho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Motoyuki Koga 1-9-18 Nakamachi, Meguro-ku, Tokyo (72) Inventor Akira Shimada Four-share company, Hatsuko Development Technology Research Co., Ltd., 3-18 Daikan City, Kanagawa Prefecture In-house

Claims (1)

[Claims] 1. A cylinder device having a diameter-expanding head at a tip thereof and a piston behind which the diameter-expanding head is tapped, is inserted into an underground pipeline to be repaired, and the piston is tapped against the diameter-expanding head. A method of straightening the pipe line by advancing the cylinder device while making the inside diameter of the pipe line at the front side of the expansion head at least shorter than the cylinder device and substantially equal to the inner diameter of the pipe line. A plurality of straightening bodies having the above are arranged, and these straightening bodies are advanced by a tapping action from a cylinder device through a diameter-expanding head so as to correct the deformation of the pipeline. Body correction method.