JPS5854975B2 - Lining method for inner pipe walls - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for lining the inner wall surface of a pipe, and particularly to a method for lining the inner wall surface of a pipe and is particularly useful for regenerating existing buried pipes such as gas pipes and water pipes.

As a method for regenerating existing buried pipes, a method has been proposed in which the inner surface of recycled pipes that have been cleaned is lined with synthetic resin tubes.

Conventionally, as a tube lining method for recycled pipes, the tube is folded flat in the vertical direction and inserted into the recycled pipe, and then a fluid is passed through the tube to expand and restore the tube to its original shape while lining the tube on its outer surface or inside the pipe. A construction method has been proposed in which the pipe is bonded to the inner wall surface using an adhesive that has been applied to the surface in advance.

In this conventional construction method, an adhesive is applied to the outer or inner surface of the tube in advance, so when the tube is drawn into the regenerated pipe, extremely large frictional resistance occurs due to the viscosity of the adhesive, requiring a large drawing force.

As a result, the joint between the drawing rope and the tube breaks during drawing, causing the rope to come off, or the tube twists within the regenerating pipe due to large frictional resistance, effectively blocking the internal space, and increasing the internal Calorie pressure. This poses a major problem in workability, as problems such as the inability to expand and restore the tube to its original state occur regardless of fluid supply.

In addition, with this conventional construction method, it is extremely difficult to ensure that the outer surface of the tube is in close contact with the inner surface of the tube throughout, and there is a drawback that air is trapped between the tube and the inner surface of the tube, which can cause partial separation. Ta.

The present invention has been made for the purpose of eliminating all the problems of the conventional method, and the present invention will be explained below based on the accompanying drawings.

When carrying out the lining method of the present invention, a film holding section 1 is placed at the front end of the pipe a to be lined.
A friction moving body A having an adhesive application mechanism section 2 at the rear thereof is set.

This friction moving body A can be pulled from the starting end toward the terminal end within the pipe a by pulling a rope 3 extending rearward from the rear end.

The film holding part 1 in the front part of the friction moving body has front and rear end plates 11
, 12, and a shaft portion 13 which connects the second end plates 11 and 12 at the center, and the front end plate 11 can be removed as appropriate by attaching and detaching a nut 14.

An annular groove 121 having an arcuate cross section can be formed on the front surface of the rear end plate 12 so as to surround the shaft portion 13 .

The lining tube 4 has a length sufficient to line the entire length of the tube a, and is fitted and held in the shaft portion 13 of the holding portion 1 in a bellows-like folded state.

This operation of inserting and holding the tube 4 is performed on the front end plate 1 of the holding section 1.
1 from the shaft portion 13.

In Fig. 1, 41 is a part of the terminal end of the folding tube 4 which has been turned over in advance in the preparation process for construction, and the terminal end is attached to the starting end of the tube a by the seventh band 5. ing.

The adhesive application mechanism section 2 at the rear end of the friction moving body is not particularly limited as long as it has a structure that allows adhesive to be applied to the inner surface of the tube a from the starting end to the terminal end.

For example, a centrifugal spray type as shown in FIGS. 1 and 2 may be employed as the application mechanism 2.

The details of the structure of the centrifugal spraying mechanism section 2 are as shown in FIG. A rotating shaft 23, a body 24 covering the area from the rear end to the front of the rotating shaft 23, and an electric motor 25 built into the body 24 (a coil 251 on the stationary side and a rotor 252 on the rotating side).
), an adhesive supply passage 25 formed in the body 24 , an injection cylinder 27 fixedly installed at the front end of the body 24 so as to receive adhesive supply from the supply passage 26 , A stirring blade 2 provided on the rotating shaft 23 in the injection cylinder 27
8, and a rotating shaft 23 so as to cover the periphery of the injection cylinder 27.
It consists of a rotating head 29 attached to the front end of the adhesive conduit 2a (extending to the outside of the tube a) (see Fig. 1).
The adhesive supplied into the injection tube 27 through the supply passage 26 connected thereto is scattered in the centrifugal direction through the slits 27a group of the injection tube 27 and the related slits 29a group of the rotating head 29. Then apply it to the inner surface of tube a.

Such centrifugal spraying can be carried out by using, for example, a third
It is also possible to use a cone-shaped presser iron 2' as shown in the figure to apply the adhesive pre-filled inside the tube a to a predetermined thickness on the inner surface of the tube a. .

Such a coating mechanism section 2 includes a mechanism section 2 (or 2').
In order to prevent the brake rolls 241 from being easily pushed and moved inside the tube 1 by fluid pressure, upper and lower pairs of legs 242 with brake rolls 241 are provided, one at the front and one at the rear (see FIG. 1).

A blank cap 6 is provided at the starting end of the pipe a, and the blank cap 6 is equipped with a pressurized fluid supply pipe 7 equipped with an on-off valve 71.

Now, from the state shown in FIG. 1, when the valve 71 is opened and pressurized fluid is supplied into the tube a through the supply pipe 7, this pressurized fluid expands into the inner surface of the tube 41 which is in an upside-down state. Acts as a force.

However, since the extension of the tube 4 in the bellows-like folded state is prevented by the rear end plate 12 of the holding part 1,
Despite the fluid pressure acting on the inner surface of the tube 41 that has been turned over, the tube 4 does not elongate.

As described above, when the structure A is gradually moved toward the terminal end by the pulling operation of the rope 3 while applying fluid pressure to the inner surface of the turning tube 41, the tube 4 is sequentially pulled out from the terminal side as it moves and is turned over. .

By applying adhesive to the inner surface of the tube a by the coating mechanism 2 in parallel with the drawing and turning over of the tube 4, the tube is placed inside the tube a as shown in FIGS. 2 and 3. 4, the inner surface of the tube a can be lined sequentially from the starting end to the terminal end.

As in the embodiment shown in FIG. 1, when the structure A is set directly inside the pipe a to be lined, the application mechanism 2 is used to apply adhesive to the inner surface of the starting end of the pipe a. Can not do it.

Therefore, in such a case, it is advisable to apply adhesive to the unapplied area a' as a final treatment after the lining is completed.

This final treatment problem can be solved by, for example, adding a short pipe a1 long enough to accommodate the structure A to the starting end of the pipe a to be lined, as shown in Figure 4. can.

An advantage of the lining method of the present invention is that the tube is folded into a bellows shape and inserted into the pipe, so it is extremely easy to insert the tube into the pipe, and the tube is not turned over inside the pipe. At the same time, the adhesive is applied to the inner surface of the tube in parallel with this, and it is bonded to the inner surface of the tube, so the lining can be installed without causing problems such as breakage of the pulling rope or inability to inflate, which is the case with conventional methods. This can significantly improve work efficiency.

Furthermore, after the tube is turned over, it is expanded under the action of fluid pressure and brought into close contact with the inner surface of the tube, so that air is completely expelled from between the inner surface of the tube and the outer surface of the tube during this close contact, eliminating the occurrence of air pockets. It has the feature of being able to be lined.

In the present invention, it is preferable to use an adhesive that does not contain a solvent, and for example, a reaction-curing type adhesive consisting of a main ingredient and a curing agent can be advantageously used.

The tube for lining is not particularly limited as long as it has flexibility and elasticity; for example, it may be selected from synthetic resins such as polyethylene, polypropylene, polyvinyl chloride, natural rubber, or synthetic rubber, depending on the use and purpose. Used selectively.

The fluid used to invert and inflate the tube may be any gaseous fluid, but air is most commonly used due to its ease of availability and economy.

It is also advantageous to use heated air or steam as the pressurized fluid because it can accelerate the reaction and hardening of the adhesive.

The fluid pressure of the fluid supplied into the tube should be large enough to turn over and expand the tube, for example 0.1~
It is selectively determined within the range of 5.0 kg/i (gauge pressure) depending on the diameter of the tube, degree of flexibility, etc.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing the situation at the start of construction in one construction example of the present invention, Fig. 2 is a longitudinal sectional view showing the situation during the same construction, and Fig. 3 is another construction example of the invention. FIG. 4 is a vertical cross-sectional view showing the situation at the start of construction in yet another construction example of the present invention, and FIG.
FIG. 3 is an enlarged longitudinal cross-sectional view showing details of the adhesive application mechanism shown in the figure. In the figure, A is the friction moving body, 1 is its film holding part,
Reference numeral 2 designates the adhesive application mechanism, 3 a rope, 4 a tube, 5 a stop band, 6 a blind cap, and 7 a pressurized fluid supply pipe.

Claims (1)

[Claims] 1 In a method for lining the inner wall of a pipe, in which the lining tube is inserted and adhered into the pipe by sequentially turning it over from the starting end fixed to the starting end of the protection pipe using the fluid pressure of the fluid forced into the pipe. , the tube is folded into a bellows shape, and the folded bellows tube is inserted and held in the shaft of a holder that is pulled and moved from the starting end of the tube toward the terminal end, and the holder is moved inside the tube. A method for lining the inner wall surface of a pipe, which is characterized by applying adhesive to the inner surface of the pipe in parallel with the movement while gradually towing the pipe from the starting end to the terminal end.