JPH0688334B2 - Lining method for existing pipes - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a lining method for an existing pipe, which is applied to rehabilitating an aged existing pipe.

(Prior Art) Buried pipes such as metal pipes and fume pipes are used for waterworks and sewers. Such a buried pipe may be corroded or cracked after long-term use. The aged existing pipe is rehabilitated by lining its inner surface with, for example, a synthetic resin.

As a method for lining an existing pipe, for example, JP-A-61-48690
In the gazette, a pipe manufacturing machine is temporarily installed at the open end of an existing pipe, a synthetic resin lining sheet is supplied to the pipe manufacturing machine, and the lining sheet is spirally wound to form a spiral pipe. A method is disclosed in which the spiral pipe is inserted into an existing pipe, and after the insertion is completed, a backfill material such as cement mortar is filled into a gap between the existing pipe and the spiral pipe.

In such an existing pipe lining method, a backfill material such as cement mortar is provided in the gap between the long lining pipes,
Because it is injected in the process after inserting the spiral tube into the existing tube,
Requires relatively high injection pressure. When the injection pressure is increased in this way, the spiral tube is deformed or damaged.

Also, when injecting backfill material such as cement mortar into the gap of a long lining pipe in the process after inserting the spiral pipe into the existing pipe, the backfill material should be injected smoothly if the air inside the gap is not removed. Can not. However, it is difficult to completely perform this air bleeding, so that a cavity is formed in a part of the gap and the strength of the lining pipeline is reduced. As described above, the step of injecting the backfill material such as cement mortar is very troublesome in terms of the properties of the backfill material and injecting it in a later step, and there is a problem in workability.

In order to solve such a problem, a lining sheet having a plurality of rib grooves on one surface along the length direction is used, and a foaming agent-containing foamable urethane resin having a controlled foaming time is applied to the rib grooves, This is supplied to a pipe-making machine and spirally wound with the rib groove of the lining sheet on the outside to form a spiral pipe, and after the spiral pipe is inserted into the existing pipe, the resin is foamed, whereby the existing pipe is formed. Attempts have been made to fill the gap between the tube and the spiral tube with urethane foam resin to integrate them.

However, in this method, the foamable urethane resin drips downward from the rib groove of the lining sheet. Therefore, it is difficult to perform the pipe manufacturing work smoothly, the resin coating is uneven and insufficient, and the gap between the existing pipe and the spiral pipe and the space of the rib groove are not completely filled with the urethane foam resin, and the lining. There is a problem that the strength of the pipeline is reduced.

Further, part of the foamable urethane resin applied to the rib groove of the lining sheet foams even while the spiral pipe is being inserted into the existing pipe, and a part of the gap between the existing pipe and the spiral pipe is closed. . In particular, when the foamable urethane resin comes into contact with water such as sewage that stays in the pipeline, foaming during the process is remarkable. Therefore, there is a problem that the rotational resistance to the spiral tube increases and the spiral tube cannot be inserted midway.

(Problems to be Solved by the Invention) The present invention is intended to solve the above problems, and an object of the present invention is to eliminate the need for a backfilling step for backfilling materials such as cement mortar, thereby improving workability. To provide a method for lining existing pipes. Another object of the present invention is to provide a lining method for an existing pipe in which a gap or a space between the existing pipe and the spiral pipe is filled with a resin foam to prevent a decrease in strength of the lining conduit.

(Means for Solving Problems) A method for lining an existing pipe according to the present invention is such that a pipe-making machine is temporarily installed at an opening end of the existing pipe, and a plurality of rib grooves are provided on the pipe-making machine in a length direction of an outer surface. In the process of supplying a lining sheet made of a synthetic resin having the lining sheet, the lining sheet is spirally wound with the surface of the rib groove on the outside to form a spiral tube, and the spiral tube is inserted into an existing tube, the lining sheet. Immediately before or immediately after winding, a space continuous in the length direction of the lining sheet is held in a part of the rib groove, and a foaming resin is injected into the remaining rib groove, and the rib groove of the lining sheet is also injected. A covering material that can be destroyed by foaming pressure is adhered to the surface having the opening to close the opening portion of the rib groove, and after the insertion of the spiral tube is completed, a foaming agent is injected into the space of the rib groove from the end surface of the spiral tube. Contact the foaming agent with the foamable resin. Then, the resin is foamed and the coating material is destroyed by the foaming pressure of the resin, and the gap between the existing pipe and the spiral pipe and the space of the rib groove are filled with the resin foam. The purpose is achieved.

(Operation) According to the method of the present invention, as described above, the foaming resin is injected into the rib groove of the lining sheet, and the surface having the rib groove is adhered with the covering material that can be destroyed by the foaming pressure to form the rib groove. Close the release part of. If you close the rib groove like this,
It is possible to prevent the foamable resin from dripping downward from the rib groove during the production of the spiral tube. Further, the foamable resin is also prevented from coming into contact with water such as sewage accumulated in the pipeline.

Further, according to the method of the present invention, a space is held in a part of the rib groove of the lining sheet, and after completion of insertion of the spiral tube into the existing tube, a foaming agent is injected into the space of the rib groove to foam the foaming agent. The resin is brought into contact with the resin for foaming. When the foaming agent is injected later to foam the resin in this way, it is possible to freely adjust the foaming time, and the foamable resin will surely foam after completion of insertion of the spiral pipe into the existing pipe, There is no foaming during the insertion of the spiral tube into the.

Furthermore, according to the method of the present invention, the above-mentioned coating material is destroyed by the foaming pressure of the resin. When the covering material is destroyed in this way,
The foamed resin expands and completely fills the gap between the existing pipe and the spiral pipe and the space of the rib groove, so that the existing pipe and the spiral pipe are integrated.

(Example) Hereinafter, the lining method of the existing pipe of the present invention will be described with reference to one embodiment shown in the drawings.

FIG. 1 is a partially cutaway vertical sectional view showing an embodiment of the method of the present invention. First, existing pipes such as fume pipes and metal pipes 1
The pipe manufacturing machine 2 is carried in through the above-ground opening of the manhole 11. Then, the pipe making machine 2 is temporarily installed at the open end of the existing pipe 1.

Next, the pressure transfer roll 21 of the pipe making machine 2 is adjusted on a concentric circumference having a diameter smaller than the inner diameter of the existing pipe. Then, from the unwinder temporarily installed on the ground, the synthetic resin lining sheet 30
Is supplied to the pipe making machine 2.

As the lining sheet 30 made of synthetic resin, a belt-shaped sheet made of polyvinyl chloride, polyethylene, polypropylene, polycarbonate, polyester, or a resin obtained by reinforcing these resins with glass fiber is used.

As shown in FIG. 3, the lining sheet 30 has a smooth inner surface and a plurality of rib grooves 32 formed in the lengthwise direction of the outer surface 31. The rib groove 32 is formed by the outer surface 31 and the T-shaped rib 33. Further, on the outer surface of one side edge portion of the lining sheet 30, a fitting convex strip 34 is provided in the length direction,
A fitting concave groove 35 is provided in the lengthwise direction on the inner surface of the other side edge portion.

The space 36 is held in a part of the plurality of rib grooves 32 of the lining sheet 30 supplied to the pipe manufacturing machine 2, and the foamable resin 4 is injected into the remaining rib grooves 32. As a specific method of holding the space 36 in a part of the plurality of rib grooves 32 of the lining sheet 30,
Of the plurality of rib grooves 32, some of the rib grooves 32 themselves are
36, or a method in which one flexible tube is inserted into all or a part of the plurality of rib grooves 32 to form a space 36 in the flexible tube. When the above flexible tube is used, the flexible tube is provided with a large number of small holes through which a foaming agent described later passes.

As the foamable resin 4, a foamable urethane resin is suitable. The foamable urethane resin is in a liquid state and contacts the foaming agent to foam and cure. Water, freon gas, or the like is used as the foaming agent for the foamable urethane resin. When Freon gas is used, it is preferable that a foaming urethane resin contains a hygroscopic agent so as not to foam even when it comes into contact with water.

To inject the foaming resin 4 into the rib groove 32 of the lining sheet 30, use a hose from a tank mounted on the track 5 on the ground.
As shown in FIG. 2, the injection pipe 52 at the tip of the pipe 51 is connected to the pipe making machine 2
Immediately before the sticking roll 22 attached to, the space 36 held in the rib groove 32 of the lining sheet 30 is left, and the ribs 32 are injected toward the remaining rib groove 32.

The foaming resin 4 is injected into a predetermined rib groove 32, and the surface of the lining sheet 30 having the rib groove, that is, the flange surface 38 of the T-shaped rib 33 is broken by the foaming pressure.
Is attached to close the open portion of the rib groove 32. As the covering material 6, for example, a pressure-sensitive adhesive paper or a pressure-sensitive adhesive film having a plastic film as a base material, which is set to have a strength capable of breaking by foaming pressure, is used. The covering material 6 is
The tape is unwound from the winding body 61 attached to the pipe manufacturing machine 2 and is pasted on the surface having the rib groove of the lining sheet 30 when passing through the pasting roll 22.

Then, this lining sheet 30 is spirally wound with the pressure transfer roll 21 of the pipe making machine 2 so that the surface of the covering sheet 6 is on the outer side, while the fitting convex strip 34 at one side edge is formed at the other side edge. The fitting concave groove 35 of the portion is overloaded and pressed to fit. By such a method, the spiral pipe 3 having a predetermined diameter and held in a cylindrical shape is formed from the lining sheet 30, and the pipe is continuously manufactured and sequentially inserted into the existing pipe.

In the present invention, the spiral tube 3 is formed by joining the both side edges by welding or an adhesive without providing the fitting ridge 34 and the fitting groove 35 on both side edges of the lining sheet 30. Is also possible.

Further, in the above embodiment, the foaming resin 4 is injected into the rib groove 32 of the lining sheet 30 immediately before being wound, and the covering material 6 is attached, but the present invention is not limited to this. Rib groove 32 of lining sheet 30 immediately after being wound
That is, the foaming resin 4 may be injected into the rib groove 32 on the outer peripheral surface of the spiral tube 3 and the covering material 6 may be attached in the same manner as in the above embodiment.

In this way, the spiral pipe 3 is sequentially inserted into the existing pipe 1,
After the insertion is completed, that is, after the tip of the spiral tube 3 reaches the open end of the other manhole 11 ', the foaming agent is injected into the space 36 of the rib groove 32 from the end surface of the spiral tube 3.

To inject the foaming agent into the space 36 of the rib groove 32 from the end surface of the spiral tube 3, use a hose from a tank mounted on the track 7 on the ground.
As shown in FIG. 4, the injection pipe 72 at the tip of 71 is used as the spiral pipe 3
It is injected toward the space 36 of the rib groove 32 on the end surface of.

The foaming agent injected into the space 36 of the rib groove 32 on the end surface of the spiral tube 3 has a T-shaped rib portion of the covering material 6 due to the injection pressure.
The foaming agent separates from the flange surface 38 of 33, and the foaming agent flows into the adjacent rib groove 32 from this separated portion, contacts the foamable resin 4, and foams the resin 4. As described above, when a flexible tube provided with a large number of small holes is inserted in all or part of the rib groove 32 and the inside of the flexible tube is the space 36, the foaming agent is flexible. It passes through a large number of small holes from the inside of the tube and comes into contact with the foamable resin around the flexible tube to foam.

When the foamable resin foams in this way, the covering material 6 is destroyed by the foaming pressure of the resin. Then, the foamed resin expands from the broken portion of the covering material 6 into the gap between the existing pipe 1 and the spiral pipe 3 and the space 36 of the rib groove 32, and finally hardens. As a result, the gap between the existing pipe 1 and the spiral pipe 2 and the space 36 of the rib groove 32 are completely filled with the resin foam.

In addition, as shown in FIG.
A large number of through holes 37 may be provided in the side wall of each T-shaped rib 33, or a large number of lateral grooves 39 leading to adjacent rib grooves 32 may be provided in the flange surface 38 of the T-shaped rib 33. Good. When such through-holes 37 and lateral grooves 39 are provided, the foaming agent injected into the spaces 36 of the rib grooves 32 of the strip-shaped lining plate 30 passes through the through-holes 37 and the lateral grooves 32 and foams the adjacent rib grooves 32. The resin 4 contacts well with the resin 4, and the foamable resin uniformly foams.

When the foaming resin is foamed, the foaming pressure may be increased depending on the type of the foaming resin or the foaming agent used, and the spiral tube 3 may be deformed, as shown in FIG. It is also possible to prevent the water flowing in the pipe from being blocked by the faucet packers 8 at both ends of the pipe, and to fill the inside of the pipe with water 9, thereby preventing the spiral pipe 3 from being deformed.

Thus, the gap between the existing pipe 1 and the spiral pipe 3 is filled with foam to form an integrated lining pipe line, and the existing pipe is rehabilitated.

(Effects of the Invention) The existing pipe lining method of the present invention is configured as described above, and the foaming resin that functions as a backfill material is injected into the rib groove of the lining sheet during the production of the spiral pipe. . Therefore, unlike the conventional method, the time-consuming post-filling step of the backfill material such as cement mortar is not required. Therefore, construction workability is improved.

In addition, a covering material is attached to the surface of the rib groove into which the foaming resin is injected to close the opening portion of the rib groove. Therefore, the foaming resin does not drip downward from the rib groove during the production of the spiral tube. Therefore, construction workability is also improved in this respect.

Further, after completion of inserting the spiral tube into the existing tube, the foaming agent is injected into the space held in a part of the rib groove to foam the foamable resin. Therefore, the foaming resin does not foam during the insertion of the spiral tube into the existing pipe, and the insertion of the spiral tube is not disabled during the insertion. Therefore, construction workability is also improved in this respect.

Further, the covering material stuck to the surface of the rib groove into which the foamable resin is injected is destroyed by the foaming pressure of the resin. therefore,
The foamed resin expands and completely fills the gap between the existing pipe and the spiral pipe and the space of the rib groove from the broken portion of the coating material. Therefore, unlike the conventional method, there is no cavity between the existing pipe and the spiral pipe, and both are well integrated, and as a result,
The reduction in strength of the lining pipe is prevented.

[Brief description of drawings]

FIG. 1 is a partially cutaway vertical sectional view showing an embodiment of the method of the present invention, FIG. 2 is a partially cutaway side view for explaining a method for injecting a foamable resin, and FIG. 3 shows a foamable resin. Partially cutaway perspective view for explaining the lining sheet after injection, FIG.
FIG. 5 is a partially cutaway perspective view for explaining a method of injecting a foaming agent, and FIG. 5 is a partially cutaway perspective view showing an example of a lining sheet. 1 ... Existing pipe, 2 ... pipe making machine, 3 ... spiral pipe, 30 ... lining sheet, 32 ... rib groove, 4 ... foaming resin, 6
…… Coating material.

Claims (1)

[Claims] 1. A pipe making machine is temporarily installed at an opening end of an existing pipe, and a synthetic resin lining sheet having a plurality of rib grooves in a length direction of an outer surface is supplied to the pipe making machine, and the lining sheet is ribbed. In the process of inserting the spiral tube into the existing tube while forming the spiral tube by spirally winding with the surface of the groove outward, immediately before or after winding the lining sheet, a part of the rib groove is formed. Maintaining a continuous space in the length direction of the lining sheet, injecting a foaming resin into the remaining rib grooves, and affixing a covering material that can be destroyed by foaming pressure to the rib groove surface of the lining sheet. The open portion of the rib groove is closed by inserting the spiral tube into the space of the rib groove from the end surface of the spiral tube after the insertion of the spiral tube is completed, and the foaming agent is brought into contact with the foamable resin to foam the resin. The foaming pressure of the resin causes the coating material to Broken, the lining method of the existing pipe, characterized in that to fill the space of the gap and the rib grooves of the existing pipe and the spiral tube in the foam of the resin.