JPS6388090A - Pipe-joint section cleaner for existing pipe - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention is mainly used for repairing existing pipes such as gas pipes buried underground, and in particular for ensuring sealing performance of pipe joints of existing pipes while they are buried. This article relates to a cleaning device for pipe joints that is installed as a pretreatment for repairs.

[Prior Art] In recent years, various methods have been proposed for repairing existing pipes, such as gas pipes and water pipes, buried underground from the inside so as to regenerate the pipes from corrosion while remaining buried.

In particular, in the case of existing gas pipes buried underground, in which cast iron pipes are connected by water-type joints, there is a need to repair the sealing properties of the pipe joints. In other words, recently, city gas has become dry natural gas instead of the coal gas that has been used for a long time. However, in the case of dry natural gas, the sealing material shrinks as it dries, creating voids. Since the sealing performance deteriorates and causes gas leakage, it is necessary to ensure the sealing performance of the pipe joint and then perform repairs to prevent sealing deterioration.

As a method for this repair, a pair of front and rear pigs that slide in airtight contact with the inner surface of the pipe are introduced into the existing pipe, and a resin is filled between the pigs and moved inside the pipe.
When the pipe fitting is located between the front and rear pigs during the moving process, a repair method has been advocated in which filling pressure is applied to the resin to fill the gap in the pipe fitting with resin.

"Problems to be Solved by the Invention" When performing repair work on this pipe joint, it is necessary to clean the inner surface of the existing pipe prior to the repair, in particular to remove dust that has accumulated in the butt gap of the pipe joint. However, conventional internal cleaning of existing pipes involves brushing or swapping to remove tar and dust that has accumulated on the inner wall of the pipe.
Since the abutment gap of the pipe fitting is recessed from the inner wall surface of the pipe, when cleaning the inside of the pipe by using fishing force to remove the dust accumulated in the recessed part of the gap, the tar and dust scraped off from the inner surface of the pipe are On the contrary, there is also the problem that it gets into the gap of the pipe joint part, and special cleaning means for the pipe joint part is required.

[Means for solving the problems] The present invention was proposed based on the above circumstances, and
It is an object of the present invention to provide a cleaning device that can reliably remove dust accumulated in a gap of a pipe joint part by a simple means.

For this purpose, the present invention cleans a pipe joint interposed in a conduit by passing a pig into an existing pipe, and the pig has a cylindrical outer body that is in contact with the inner surface of the existing pipe. It is equipped with a contact fin that maintains airtightness, and has a fluid passage inside the body that guides pressurized fluid supplied from the rear of the pig into the pipe from the rear end of the pig to the front, and a fluid passage that guides the pressurized fluid in the fluid passage. A fluid ejecting means is provided with an ejection nozzle that ejects the fluid diagonally forward and outward at a predetermined angle from the front part of the pig,
When the pig moves inside the pipe and passes the position of the pipe joint, the pressurized fluid jetted from the jet nozzle of the fluid passage is directly jetted from an oblique angle toward the gap recess of the pipe joint. It is configured to rotate within the gap recess and eject dust in the gap recess forwardly.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 indicates an existing pipe that is a gas pipe buried underground. It has been connected for a long time.

In addition, when repairing the pipe joint 2, the existing yi is divided into units of length suitable for repair, and a large number of pipe joints 2 interposed in the pipe within that section are cleaned and repaired. It is.

In addition, the above-mentioned pipe joint part 2 has a large diameter part 2a provided at the end of one pipe, as is conventionally known, and a pipe f@ of the other pipe.
2b are butted against each other, and this butt-fitting part is filled with mushir material 4, and the opening is filled with lead material 5.
It has a connection structure that is sealed with a plug, and since a gap 3 is usually generated inside the abutting portion, there is a problem that dust accumulates there.

In the present invention, inside the existing pipe 1 to be cleaned,
A cleaning pig 8 is introduced. This pig 8 has a cylindrical shape with a truncated conical front part, and on its outer circumferential body there are contact plates 9 on the front and rear sides that maintain airtightness by contacting the inner surface of the existing pipe 1. It is formed in steps. The pig 8 also has a fluid passage 8a inside its body that guides pressurized fluid from the rear end of the pig to the front, and a fluid passage 8a that guides the pressurized fluid in the driftwood passage 8a from the front part of the pig at a predetermined angle diagonally forward and outward. A fluid ejecting means is provided which includes an ejecting nozzle 8b that ejects the fluid in the direction.

In addition, traction lobes 6.7 are connected to the front and rear of the pig 8,
This pulling operation of the lobes 6.7 allows the pig 8 to move within the existing pipe 1.

Further, as described above, means is provided for supplying pressurized fluid (in this embodiment, pressurized air flow) into the existing pipe 1 from the rear in the moving direction of the pig 8.

Therefore, when the pig 8 is moved along the inside of the pipe by the pulling operation of the row 16.7 while the above-mentioned pressurized fluid is supplied into the inside of the existing pipe 1, pressurization is blown into the pipe from behind the pig 8. The fluid is ejected from the rear end of the pig 8 through a fluid passage 8a and from an ejection nozzle 8b at the front of the pig.

At this time, since the pig 8 has contact seals 9 formed on its outer peripheral body in two stages, front and rear, which maintain airtightness by contacting the inner surface of the existing pipe 1, the pressurized fluid flows into the pig 8. It does not blow forward through between the outer periphery and the inner surface of the pipe.

Further, the ejection nozzle 8b of the fluid passage 8a is opened at the front truncated conical surface of the pig 8 so as to eject pressurized fluid diagonally forward and outward at a predetermined angle. When passing through a position corresponding to the pipe joint part 2, the pressurized fluid jetted from the jet nozzle 8b is directly directed from an oblique angle into the abutting gap (gap recess 3) of the pipe joint part 2. It is blown in, swirls inside the gap recess 3 and flows in front of the pig 8 as shown by the arrow in the drawing.

As a result, pressurized fluid is directly blown into the gap recess 3 from an oblique angle even in the abutting gap (gap recess 3) of the pipe fitting 2, which is a concave part of the pipe, and the gap recess 3
By circulating the dust inside the gap recess 3, the dust inside the gap recess 3 can be reliably ejected to the front of the pig 8.

Further, as the pig 8 moves, the dust that is removed to the front of the pig 8 is sequentially pushed forward in the direction of movement within the pipe and is removed from the other end of the pipe. Exclusion is also automatic.

In addition, in the description of the above-mentioned embodiment, the pressurized fluid of positive pressure is transferred to the pig 8.
The dust was blown away from the gap recess 3 of the pipe fitting 2 by supplying it from the rear of the pig 8, but from the front of the pig 8.

The dust may be removed by suction by applying negative pressure inside the tube.

Further, positive pressure and negative pressure may be applied to the front and rear of the pig 8 at the same time, and in this embodiment, pressurized fluid supply means are provided at both end openings of the existing pipe 1 in the repair section to enable such treatment. It is being

[Effects of the Invention] As explained above, the present invention is configured such that the pressurized fluid supplied to the rear of the pig is jetted diagonally forward and outward at a predetermined angle from the jet nozzle at the front of the pig. Therefore, when the pig passes through the pipe, even if the abutment gap (gap recess) of the pipe joint intervening in the pipe is concave, pressurized fluid will flow into the gap recess at an oblique angle. The dust in the gap recess can be reliably ejected and removed to the front of the pig by blowing directly through the gap recess and circulating in the front of the pig. It becomes possible to perform cleaning accurately.

In addition, as the pig moves, the dust that is blown out from inside the gap recess in front of the pig is pushed by the pig in the direction of movement, so the dust is automatically removed from the pipe. This also eliminates inconveniences such as dust re-accumulating in the gap recess of the pipe joint after the pig has passed.

[Brief explanation of the drawing]

The drawing is a longitudinal side view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Existing pipe, 2... Pipe joint part, 2a... Large diameter part of pipe joint part, 2b... Other pipe end of pipe joint part, 3...
... Gap recess, 4... Sealing material, 5... Lead material, 6.
7... Towing rope, 8... Cleaning pig, 8a...
-Fluid passage, 8b...Ejection nozzle, 9...Contact fin.

Claims (1)

[Claims] In a device for cleaning pipe joints interposed in the pipeline by passing a pig into the pipe of an existing pipe, the pig has a cylindrical outer circumferential body that comes into contact with the inner surface of the existing pipe to maintain airtightness. In addition, there is a fluid passage inside the body that guides pressurized fluid supplied from the rear of the pig from the rear end of the pig to the front, and a fluid passage that guides the pressurized fluid in the fluid passage from the front of the pig to a predetermined direction. A fluid jetting means is provided with a jetting nozzle that jets diagonally forward and outward at an angle, and when the pig moves inside the pipe and passes the position of the pipe joint, the fluid jetting means jets from the jetting nozzle of the fluid passage. 1. An apparatus for cleaning a pipe joint of an existing pipe, characterized in that the pressure fluid is directly ejected from an oblique angle into the gap recess of the pipe joint.