JP2014064961A - Cleaning pig for waterwork pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide such a pig for waterworks that the pig can remove dirt of deposit adhering onto the pipe inner wall surface by progressing smoothly without stopping through even a pipeline in which the ratio of the sectional area of the pig and a branch pipe is in the level of 4%-7% and a conventional pig of a foam having a three-dimensional mesh-like skeleton structure not having a cell film is impassable.SOLUTION: In a cleaning pig for a waterwork pipe, a pig body 1 is contracted and inserted from one branch pipe 12, and advanced into a main pipe 11 by receiving a fluid pressure, then expands immediately to the size having a contact with the pipe inner wall surface 11a by elastic force carried by the pig body 1, to thereby remove dirt or foreign matters with transferring the pig body 1, and to take them out from the other branch pipe 12. The pig body 1 is a circular foam having a three-dimensional mesh-like skeleton structure not having a cell film as a whole, and is coated on the whole surface with a foam breaking paste 4 comprising a non-pressure fluid permeable foaming resin having compressibility and flexibility equal to those a soft continuous foamed body, and the inside of the pig body 1 is formed as a hollow part 5, and a plurality of holes 7 are bored on the outer peripheral surface.

Description

  The present invention relates to a pig for cleaning a water pipe buried in the ground. More specifically, the present invention relates to a pig that is inserted into a water pipe by using a branch pipe such as a fire hydrant connected to the water main, and pumped to the inside. The present invention relates to a water supply pipe cleaning pig that removes dirt and foreign matter adhering to a wall surface.

  Conventionally, water supply pipes buried in the ground accumulate deposits on the inner wall surface during use for a long period of time, resulting in dirt and foreign matter. To remove the dirt and foreign matter, insert a spherical or bullet-shaped pig made of urethane foam slightly larger than the inner diameter of the main pipe into the pipe, and pump it with water pressure so that the outer peripheral surface of the pig is Dirt and foreign matter were removed by contacting the inner wall surface.

  When using this cleaning pig, determine the pipes to be cleaned of the distribution pipes buried in the ground, excavate potholes at both ends of the pipes, and open openings at both ends of the pipes. Connect the insertion tube and the discharge tube, insert a pig from the insertion tube, pump it with water pressure, rub the outer peripheral surface of the pig against the inner wall surface of the tube, remove the accumulated dirt and foreign matter, and take it out of the discharge tube and clean it I was doing.

  This method requires a series of work such as excavation work, opening work, and pipe connection work as described above, and after the completion of cleaning, it must also be restored to the original state, which requires a great deal of labor and time. In addition to having a fatal disadvantage that the water shut-off time becomes long, there is a problem in that the opening of the opening causes a foreign matter to be mixed and a sanitary work is required.

  Therefore, existing waterworks pipes can be used as they are without any troublesome work such as excavation work, opening work, pipe connection work, landfill restoration work as described above, and branch pipes such as fire hydrants are used. As a result, the applicant has developed a pig that cleans the water supply pipe safely and efficiently in a short time, and it is being implemented in various places and has been well received by water supply managers.

  This pig is a pig made of a foam having a three-dimensional network structure without a cell membrane that leaves only a hexagonal skeleton by removing the cell membrane from the flexible urethane foam. Three-dimensionally entangled and three-dimensionally connected, with a void between the skeleton and a high porosity. It has the same shrinkage and flexibility as a soft foam, and is non-pressure fluid permeable. A foam-breaking paste made of the above foamed resin is coated on the entire surface. It has excellent resilience, and when it enters a thick main through a thin fire hydrant, it instantly expands and contacts the inner wall of the main, and is pumped by water pressure. Then, the dirt adhering to the inner wall surface of the pipe is removed and discharged from the other small-diameter fire hydrant pipe (see, for example, Patent Document 1).

JP 2009-66522 A

  However, the diameters of branch pipes such as fire hydrants connected to the main pipe of the water supply pipe are limited to three types of 50φ, 75φ, and 100φ. On the other hand, the diameter of the main pipe is generally 75φ, 100φ, 150φ, 200φ, 250φ, etc., and these sizes occupy about 70%, but in some large cities with large water consumption, 300φ and 400φ Large diameters have also been used, and some of them have a large diameter of 500φ, but are rarely used for water pipes distributed to homes, and are generally untreated water (raw water) It is used as a transfer pipe for water intake, transfer, waterworks treatment plant communication, or communication between cities.

  The pig made of a foam having a three-dimensional network skeleton structure without the cell membrane has, for example, a main pipe diameter of 250φ, a branch pipe diameter of 75φ, and a ratio of the sectional area of the branch pipe to the main pipe of about 9 mm. % Pipeline, main pipe diameter is 150φ, branch pipe diameter is 50φ, the ratio of the cross-sectional area of branch pipe to main pipe is about 9.76%, main pipe diameter is 300φ, branch pipe If the diameter of the pipe is 100φ and the ratio of the cross-sectional area of the branch pipe to the main pipe is about 11%, the pig inserted from one branch pipe receives the water pressure and enters the main pipe and immediately expands. The outer peripheral surface of the pig comes into contact with the inner wall surface of the main pipe, and as it progresses, dirt can be removed and discharged from the other branch pipe for cleaning. That is, it is known that if the ratio of the cross-sectional area between the branch pipe and the main pipe is about 9 to about 11% or more, the pig proceeds smoothly without stopping on the way. In the case of a main pipe of 350φ or 400φ, the ratio of the cross-sectional area between the branch pipe and the main pipe is large, and the pipe may be cleaned by passing through a pig by attaching a continuous water branch pipe.

  As described above, the fire hydrant method for discharging this pig from one branch pipe to the other does not require excavation work, opening work, pipe connection work, landfill restoration work, etc. Because it can be used as it is and work can be completed efficiently and safely in a short period of time, the water supply manager is in the 4% range where the ratio of the cross-sectional area between the branch pipe and the main pipe is more severe than the aforementioned 9% lower limit. To pass through.

  For example, the diameter of the branch pipe is 100φ, the diameter of the main pipe is 350φ, the pig is 360φ, the ratio of the sectional area of the branch pipe to the pig is about 7.4%, the diameter of the branch pipe is 100φ, and the diameter of the main pipe is 400φ. , The pipe is 410φ, the ratio of the sectional area of the branch pipe to the pig is about 5.95%, the diameter of the branch pipe is 75φ, the diameter of the main pipe is 300φ, the pig is 310φ, the ratio of the sectional area of the branch pipe to the pig Is 5.85%, the diameter of the branch pipe is 100φ, the diameter of the main pipe is 450φ, the pig is 460φ, the ratio of the cross-sectional area of the branch pipe to the pig is about 4.73%, the diameter of the branch pipe is 75φ, and the main pipe The diameter of the tube is 350φ, the pig is 360φ, and the ratio of the cross-sectional area of the branch pipe to the pig is about 4.34%. There has been a demand for the development of a pig that passes through a pipeline that cannot be passed by the foam pig.

  The present invention has been researched and developed with the object of solving the above-described problems, and has not been able to pass through a conventional foamed pig having a three-dimensional network skeleton structure without a cell membrane. Pipes with a cross-sectional area ratio of 4% to 7% are allowed to move smoothly through the main pipe without stopping the pig within the allowable pressure (0.7 MPa) to remove dirt and foreign matter adhering to the inner wall of the pipe. It is an object to provide a cleaning pipe for a water supply pipe to be cleaned.

Means to solve the problem

  As a means for solving the above-mentioned problems and achieving the object, the present invention is designed such that when the pig body is contracted and inserted from one branch pipe and is advanced to the main pipe under fluid pressure, the elasticity of the pig body is obtained. The pipe is immediately expanded to a size that contacts the inner wall of the pipe, removes dirt and foreign matter along with the pumping of the pig body, and is taken out from the other branch pipe. This is a circular foam with a non-three-dimensional network skeleton structure, and the entire surface is coated with a foam-breaking paste made of a non-pressure fluid-permeable foam resin that has the same shrinkage and flexibility as a soft foam. In addition, a water supply pipe cleaning pig characterized by having a hollow inside the pig body and having a plurality of holes in the outer peripheral surface was developed and adopted.

  Further, in the present invention, in the cleaning pig of the water supply pipe configured as described above, the cleaning pig can pass through a pipeline having a cross-sectional area ratio of 4 to 7% between the branch pipe and the pig. The cleaning pig of the water supply pipe and the cleaning pig have a thickness of 20 to 100 mm. The cleaning pig of the water supply pipe and the cleaning pig have a plurality of holes of 10 to 60φ on the outer peripheral surface. We have developed and adopted a water-pipe cleaning pig, which is characterized by

  The present invention is a foam having a three-dimensional network skeleton structure that does not have a cell membrane as a whole, and is made of a non-pressure fluid permeable foam resin that has the same shrinkage and flexibility as a soft foam. Since the inside of the spherical pig body coated with the paste on the entire surface is formed in the hollow portion and a plurality of holes are formed on the outer peripheral surface, the weight is reduced and the usability at the construction site is improved. Also, it can be easily folded by folding it through the hole when it is folded in the atmosphere, and the launch device with an opening that allows the air in the cavity to escape and the volume to be reduced and the contracted size to enter can be used. A large-diameter insertion device is not required, and the work equipment on the entrance side becomes compact. In addition, the water in and out of the cavity of the pig body 1 is effectively shrunk and expanded by the force of pressure water that pushes the pig body when the fire hydrant is inserted, when the main pipe is advanced, and when the fire hydrant is discharged. Thus, it is possible to pass through a pipeline having a ratio of the cross-sectional area between the branch pipe and the pig that has not been able to pass so far at a level of 4 to 7% at an allowable pressure (0.7 MPa).

It is a front view of a pig main body. It is an enlarged view of the A section of FIG. It is a center longitudinal cross-sectional view of a pig main body. It is an enlarged view of the B section of FIG. It is a simplified side view of a waterworks pipeline. It is a front view of the state where the spherical pig body was pressed and reduced. It is a longitudinal cross-sectional view in a state where the pig body is launched from the launcher and enters the main pipe. It is a longitudinal cross-sectional view in which the pig main body is progressing through the main pipe. It is a longitudinal cross-sectional view of a state where the pig body reaches the branch pipe and is reduced and enters the branch pipe. It is explanatory drawing of the passage for a passage test of a pig main body. It is explanatory drawing of the passage for a passage test of another pig main body.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. Reference numeral 1 denotes a pig body for cleaning a water supply pipe line. As shown in FIGS. Is a spherical body having a skeleton structure, and is a structure in which the cell membrane is removed from the foam to leave only the substantially hexagonal skeleton 2, and the adjacent skeletons 2 and 2 are intricately and sterically entangled three-dimensionally. It is originally connected and has a high porosity with pores 3 between the skeleton 2 and the skeleton 2, and has a contractibility equivalent to that of a soft open-cell foam having a foam density of 0.02 to 0.06 g / cm ^3. It is a known pig coated with 0.05 to 0.8 mm of foam breaking paste 4 made of a foamed resin that is flexible and non-pressure fluid permeable.

  Reference numeral 5 denotes a hollow portion inside the pig body 1, and the hollow portion 5 can obtain excellent elasticity by setting the thickness 6 to 20 to 100 mm although it depends on the outer diameter of the pig body 1. If it is 20 mm or less, the elasticity is inferior and it is not suitable because it takes time to restore the original spherical shape, and if it is 100 mm or more, it is not suitable because the internal cavity becomes small and shrinkage and expansion are not good, and the above range is suitable. It is.

  Reference numeral 7 denotes a hole randomly drilled at the position of the outer peripheral surface of the pig body 1, and the hole 7 is a straight hole or a curved hole such as a circle, an ellipse, or an oval. The size of the hole 7 varies depending on the diameter of the pig itself, but is preferably 10 to 60φ, and it is easy to reduce the number of the holes 7 to be drilled, and it expands from the reduction to the original spherical shape. It is optimal for reasons such as good water inflow.

  The pig main body 1 configured as described above is for cleanliness by removing dirt and foreign matter in the pipe by placing it in a water supply pipe having a large difference in diameter as shown in FIG. That is, the branch pipes 12, 12 connected at predetermined intervals of the water main pipe 11 buried in the ground are projected from the ground into the recess 13 such as a digestive plug box having a certain depth, The branch pipe 12a is provided with a launching device 14 and the other branch pipe 12b is provided with a recovery device 15 to clean the water supply pipe line.

  That is, the spherical pig body 1 is pressed to draw out the air in the cavity 5 to reduce the size (FIG. 6). The pig main body 1 that has been folded and reduced is put into the launching device 14, and fired by water pressure and fed into the main pipe 11. The pig main body 1 sent in the reduced state takes in water from the elastic recovery force of the pig main body 1 and a plurality of holes 7 drilled in the outer peripheral surface, and instantly restores the original spherical shape to the inside of the main pipe 11. It will be in the state which contacted the wall surface 11a (FIG. 7). Pig body 1 restored to its original spherical shape progresses as an incompressible solid sphere with water in the balance of forward water pressure and back pressure, and removes dirt and foreign matter 15 deposited and adhered to inner wall surface 11a. (FIG. 8). Furthermore, when it reaches the branch pipe 12b of the fire hydrant serving as the outlet, the forward water closed by the front valve 16 becomes the wall 17 and is pushed into the cavity 5 of the pig body 1 by being pushed by the water pressure from the inlet side. Are crushed and shrunk and deformed to become small and smoothly enter the branch pipe 12b and be discharged (FIG. 9).

  As described above, in the embodiment of the present invention, the example in which the fire hydrant is a branch pipe has been described. However, the present invention is not limited thereto, and the air pipe or the drain pipe may be a branch pipe. Needless to say, various design changes can be made without departing from the scope of the invention.

  Next, the pig passage test of the present invention will be described. In the experimental example, the ratio of the cross-sectional area between the branch pipe and the pig is in the range of 4 to 7%, and the conventional pipe having a three-dimensional network skeleton structure without a cell membrane cannot pass through. Insert the pig body from the branch pipe, proceed to the main pipe under water pressure, test the passage test discharged from the other branch pipe and the erased state of applying sand or scale simulated glue to the pipe line did.

Experimental example 1

  As shown in FIG. 10, the 400φ mortar lining main pipe 21 has a length of 50 m, the 100φ fire hydrants 22 and 22 are connected to the upstream side and the downstream side, and the launcher 23 and the catcher 24 are installed at the tip thereof. A pump 25 and a water tank 26 were installed on the 23 side, and a recovery tank 27 was provided on the catcher side.

The launcher 23 is pressed and reduced in size by deforming the main body 1 of a pig (product name: PUK Super Ball Poly Union Kogyo Co., Ltd.) having 10 holes 7 having an outer diameter of 410φ, a wall thickness of 6 mm, and a diameter of 50 mm. The pig body 1 was immediately restored to a spherical shape and proceeded smoothly and discharged from the catcher 24 at 0.4 MPa. The length of the main pipe 21 was 50 m, and the water amount was 1 m ³ / min. The water was discharged from the catcher side in 7 minutes 20 seconds to 40 seconds. Theoretically, since the tube capacity is 6 m ³ , if the pig main body 1 proceeds in a completely sealed state, it will be discharged in 6 minutes. Since the insertion / discharge time from the fire hydrants 22, 22 is also included in the above passage time, as a whole evaluation, the hole 7 does not affect the passage performance of the pig body 1, and the pig body 1 stops due to leakage from the hole 7. There was not. In addition, although there was a place where a pseudo glue was applied to sand and scale on the inner surface of the main pipe 21, the glue was removed and discharged well. The pig body 1 recovered in the recovery tank 27 was restored to its original spherical shape.

Experimental example 2

As shown in FIG. 11, a pig (product name) in which eight holes 7 having an outer diameter of 310φ, a wall thickness of 60 mm, and 40φ are randomly drilled in a launcher 33 of a pipe line having a main pipe 31 of 300φ and a fire hydrant 32 of 75φ. PUK Super Ball (made by Poly Union Industrial Co., Ltd.) Pressing down the main body 1 and deforming it, launching it from the launcher 33 at a pressure of 0.45 MPa and pumping it to the main pipe 31 immediately restores the pig main body 1 to a spherical shape. It proceeded smoothly and discharged from the catcher 34 at 0.4 MPa. The length of the main pipe 31 was 10 m and the water amount was 0.8 m ³ / min. The water was discharged from the catcher 34 in about 58 seconds. In addition, there was a portion where the lipstick was applied on the inner surface of the main pipe 31 as a stain, but the lipstick was erased cleanly.

Experimental example 3

Except for the main pipe 31 having a diameter of 350φ and the fire hydrant 32 having a diameter of 100φ, a pig having 10 holes 7 having an outer diameter of 360φ, a wall thickness of 60 mm, and a diameter of 40φ is randomly drilled on the launcher 33 having the same pipe line as the experimental example 2 (product name PUK). Superball Poly Union Industrial Co., Ltd.) Pressing the main body 1 to reduce and deform it, launching it from the launcher 33 at a pressure of 0.35 MPa, and pumping it to the main pipe 31, the pig main body 1 is immediately restored to a spherical shape and smooth And discharged from the catcher 34 at 0.3 MPa. The length of the main pipe 31 was 10 m, the water amount was 0.8 m ³ / min, and the water was discharged from the catcher 34 in 1 minute 20 seconds. In addition, there was a portion where the lipstick was applied on the inner surface of the main pipe 31 as a stain, but the lipstick was erased cleanly.

Experimental Example 4

Except for the main pipe 31 of 450φ and the fire hydrant 32 of 100φ, a pig having 12 random holes 7 having an outer diameter of 460φ, a wall thickness of 25 mm, and a diameter of 50φ in the launcher 33 of the same pipe line as the experimental example 2 (product name PUK) Superball Poly Union Industrial Co., Ltd.) Pressing the main body 1 to reduce and deform it, launching it from the launcher 33 at a pressure of 0.6 MPa, and pumping it to the main pipe 31, the pig main body 1 is immediately restored to a spherical shape and smooth And discharged from the catcher 34 at 0.65 MPa. The length of the main pipe was 10 m, the water amount was 1.2 m ³ / min, and it was discharged from the catcher side in 1 minute 40 seconds to 45 seconds. In addition, there was a portion where the lipstick was applied on the inner surface of the main pipe 31 as a stain, but the lipstick was erased cleanly.

Experimental Example 5

  Except for the main pipe 31 having a diameter of 500φ and the fire hydrant 32 having a diameter of 100φ, a pig having 14 holes 7 having an outer diameter of 510φ, a wall thickness of 25 mm, and a diameter of 60φ in the launcher 33 of the same pipe line as the experimental example 2 (product name PUK Super Ball (made by Poly Union Industrial Co., Ltd.) The main body was pressed to be reduced and deformed, and the pressure was increased to 1.2 MPa, but the pig main body 1 remained stopped in the launcher 33 and did not enter the SGP main pipe 31. Since the pressure for pumping the pig body 1 is determined to be within 0.7 MPa at the maximum for safety, the insertion was judged to be impossible and stopped.

  INDUSTRIAL APPLICABILITY The present invention can be effectively applied as a pig that cleans pipe lines having greatly different thicknesses from a thin branch pipe to a thick main pipe or from a thick main pipe to a thin branch pipe.

1 Pig body
4 Bubble breaking paste
5 Cavity
7 Hole 11 Main pipe 11a Inner wall surface 12 Branch pipe 12a One branch pipe 12b The other branch pipe 15 Dirt

Claims (4)

  When the pig main body is contracted and inserted from one branch pipe, and is advanced to the main pipe under fluid pressure, it immediately expands to a size that contacts the inner wall surface of the pipe due to the elastic force of the pig main body. The main body of the pig body is a circular foam having a three-dimensional network skeleton structure with no cell membrane, which removes dirt and foreign matter and removes it from the other branch pipe. A foam-breaking paste made of non-pressure fluid permeable foaming resin, which has the same shrinkage and flexibility as foam, is coated on the entire surface, making the inside of the pig body a hollow part and multiple outer peripheral surfaces A water supply pipe cleaning pig characterized by having a plurality of holes.   The water cleaning pipe cleaning pig according to claim 1, wherein the cleaning pig can pass through a pipe line having a cross-sectional area ratio of 4 to 7% between the branch pipe and the pig.   The water cleaning pipe cleaning pig according to claim 1, wherein the cleaning pig has a thickness of 20 to 100 mm.   The water cleaning pipe cleaning pig according to claim 1, wherein the cleaning pig is formed with a plurality of holes of 10 to 60φ on an outer peripheral surface.