JPH0333595A - Pipe repairing method - Google Patents

Abstract

PURPOSE:To ensure pressure resistant sealing performance and enable easy repair by conveying a repairing sleeve, a shape memorizing polymer with a glass transition point of the working temperature of a piping or more, molded after the shape of a part to be repaired, to the place where the part to be repaired is located, and heating the repairing sleeve to recover its memory. CONSTITUTION:A repairing sleeve 1 is conveyed to a corroded/thinned part 5 as the part to be repaired of a piping 3 and integrated with the piping 3. The repairing sleeve 1 is a shape memorizing polymer with the glass transition point of the working temperature of the piping 3 or more, and is molded after the shape of the corroded/thinned part 5. The sleeve 1 is conveyed, as it is in the contracted shape, to the corroded/thinned part 5, and heated at more than the glass transition point and less than the molding temperature to recover its memory, thus being integrated with the piping 3. The pressure-resistant seal can be obtained easily in this repair, thereby ensuring rapidity and high efficiency in repair.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for repairing corroded and thinned parts of various types of piping.

(Prior Art) In general, the casing is buried in the ground or water, or covered with a heat insulating material. Therefore, when repairing the corroded and thinned part of K1', it is customary to repair it from inside the pipe.

Conventional repair methods from within the pipe include overlaying by welding, sleeve expansion, and inversion sealing.

FIG. 1 is an explanatory diagram of the overlay method, in which a welding torch 13 is attached to the tip via a turning mechanism 171, a welding machine 15 is attached to the rear end, and a one-digit pipe inner growth 10 is attached to the piping 3. 71 while rotating the welding parts 1 and 13.
There is a type-C in which the overlay bead 16 is formed spirally along the inner surface. In this method, the welding must be carried out with heat so that the welding does not fall on the thin wall of the frame 11. 10g/m
It is inefficient because it is softened by about in.

FIG. 5 is an explanatory diagram of the sleeve expansion method.
From the inner diameter of the corroded thinned part 5 of the distribution pipe 93 (Prepare a small-diameter sleeve 19 about 1° and apply a straight solder 20 to its outer surface.

4 + 1 + L is included in the corroded sweetfish meat part at the conveyor flange 17 at the end, and the gas burner 18 is turned 1 without retracting the 1 jl O in front of the pipe.
1] 1 mechanism] and 4 are rotated at the same time to hit the heating rowie. In order to perform good brazing at this joint, it is necessary to connect the inner surface of pipe 3 with the inner surface of pipe 3. +Ii It is necessary to keep the gap with the outer surface of the working sleeve 19 small and uniform. Therefore, it is difficult to push in the repair sleeve 19, and it can only be inserted into piping that is straight and has a smooth interior.

Fig. 6 shows the explanation of the inverted seal θ, 1-&l, and the seal pose 21 is taken at the front 1!10 of the pipe.
This is to push in the meat part 5. This method is strongly restricted in that it can only use a synthetic resin-based material with Mi% and 'j' meat such as a nord pose. Also, it cannot be applied to curved pipes with elbows'' and 9.

(Problem to be solved by the invention) The present invention solves the shortcomings of the original 4% method, and also solves the problems of the 4% method and improves the quality of the pipes. It is possible to preserve the nature of the pipes, easily and quickly remove the insects, and to develop an efficient pipe repair method. It is something to do.

(Means for Determining Ej I Overseas) The present invention provides
In the pipe repair method in which the repair sleeve is transported to a 4% illusion part and the sleeve is integrated with the piping, the glass transition point is reached at a temperature of 12°C or more. The area to be repaired (1) is
1 that fits the shape of '/! Prepare a sleeve for Mli (]ζ in which the shape is memorized by molding with
The glass is heated to a temperature of 111N to form a straight line, then cooled and fixed above the transition point of the glass 111N while maintaining the contracted shape, and then
After transporting the ring-shaped sleeve to the above-mentioned hli repair target part f1'/, the above-mentioned 1. '1: Visualize the shape of the drawer and integrate it with the piping.
, there is a blue repair method °C with +7 signs.

Note that the contracted shape of the sleeve is, for example, i7i J1
It can be made into a shape. When using a repair sleeve in which the RF adhesive is retained in the 1111 part of the shape, the molded shape of the sleeve is changed to Since uniform tu f'i agent 1i'j can be formed at the interface between
il+1Ji'l- Seal ↑You can beat the cow ;B'5.

(f'IJ1j) In the present invention, a supplementary sleeve is made of a shape memory polymer.

- In general, shape memory polymers refer to the acid form lI! j's Jl
The shape of the polymer was stored in the glass for 11 minutes, and then the polymer was
By heating to a temperature higher than the molding temperature at ζ transfer temperature, microbrown interlocking of polymer molecular chains is started,
The above-mentioned micro-Brownian motion is stopped by causing the bending to occur and deforming it into a predetermined shape, and cooling it to below the glass transition point while maintaining the same shape. Set. Thereafter, if necessary, by heating the mud layer to a temperature above the glass transition point and below "C forming 1j+ljt", the above-mentioned memory can be combined and passed through to the shape at the time of C forming.

The repair sleeve of the present invention is manufactured by molding it into a shape that matches the shape of the repair/j difference part A 17 using a shape memory polymer and memorizing the molded shape. The sleeve is folded up and reduced in diameter so that it can be transported.
There is a method that changes the memory shape to the same 7s4 after transporting it to the target part (+'t. Therefore, it is inconvenient to use the same function while transporting it in the pipe. The glass transition point is at least IJ lower than ifl+'1 degree of the piping.
:+i It is necessary to use a 10° polymer.

For example, if the room dl is arranged,
℃ or below -11, lamp 7 or about 30℃ i11;A
It is preferable to use other shape memory polymers that have a high glass transition temperature. When the glass transition point exceeds 11°, the shape of the target part (1'/) becomes the same (<, 7, -kj ;Y+°') from the glass transition point. !
There is a spirit that heats it to n'+ degrees, and heating means are restricted.

Examples of shape memory polymers that can be used in the present invention include polyurethanes obtained by polymerizing diisosiaphor 1, it□i molecules, polyols, and 1L1 extenders using a prepolymer method. Physically, 0) 4,4°-diphenylmethane diisocyanate with molecule fit 250, molecule-! jt 400 of polypropylene glycol and molecule (i)) 62 of ethylene glycol as a chain extender in a molar ratio of 1.49:1.0:0.51 to form a bripolymer 〇, and the combined XJ port Polyurethane with a degree of Iizization of 10w1% and a glass transition point of 55°C, ■
Molecule j'+i', 250 4,4"-cyphenylmethane diisocyan-1-1 molecules (1j: 800 bisph J
, Noruba→propylene oxide, and bis(2-hydroquinethyl)hydroquinone with molecule 1+f:198 as a chain extender in a molar ratio of 1.81:1.0:0.
81 and polymerized by prepolymer method /r'+'
Examples include polyurethane having a glass transition temperature of 48° C. with 5 wt % of k 1 oxide. These polyurethanes can be formed into a sleeve shape for repair by extrusion θ.

Next, looking at the shape of the repair sleeve, the diameter is φ. Since it is necessary to convey the sleeve through the inside of the pipe and also pass through the elbow part as shown in Fig. 1, the outer diameter of the sleeve is sufficiently small. It is necessary to reduce the diameter to The diameter reduction is performed, for example, at the 21st kl (+
)) Is it possible to make the cross section i11 shape? Y('
1. This may be convenient for both understanding and understanding, but is not limited to this. The diameter reduction method involves heating a sleeve made of memory polymer that is drawn into a cylindrical shape as shown in No. 21 χ 1 (a), memorized the shape, and then heated to a temperature above the glass transition temperature. For example, the rod-shaped body is pushed in from all directions and placed in the glass in that state; the state is fixed by cooling it to below the transition point.This diameter-reducing sleeve is used for piping After the part to be repaired is brought to 1γ, it is heated above the glass transition point to form the molded shape.In order to uniformly heat this hli 4'6 sleeve, It is preferable to insert a hot air heater into the center of the sleeve whose diameter has been reduced to the h1-shaped cross section as described above, so as to provide one force and one heat from one knot side.Furthermore, the four star-shaped parts carry a contact agent. By doing so, the contact agent does not come into contact with the piping while the sleeve is being transported during the sleeve, and when the sleeve is returned to its cylindrical shape, the sleeve and the pipe are removed.
It is possible to form a uniform adhesive layer at the interface between the two, and it is also possible to fix the two together.This adhesive can be coated with a thin resin filter if necessary. You can also store it in a bag.

(example) The 'saw embodiment will be explained along the lines of FIGS. 1 to 31x1.

First, using polyurethane having a glass transition temperature of 55 DEG C., a circular f7j-shaped sleeve as shown in FIG. Next, the sleeve was heated to 75° C. and folded into the f+1 cross-section shape shown in FIG. Said 74
As shown in FIG. 3(a), thin vinyl bags 2 were filled with adhesive and placed in the four parts of the J-shape to form a repair sleeve 1. In addition, when repairing the bent pipe section, please refer to Fig. 3 (l)
) After molding the sleeve into a shape that matches the shape of the part and memorizing the shape, heat the sleeve in glass to It is best to replace the sleeve with the old pipe, reduce the diameter, cool and solidify, and apply adhesive to the four parts to form a repair sleeve.

Yes, there is a Jfd thickening part 5 located at the 9th part of the elbow part 4 of the pipe 3.
was repaired. The repair sleeve 1 was connected to the thin cylindrical hot air heater 6 and fixed with a cap 8. Part 1
1^ The wind heater 6 is installed at the tip of the guide 9 (=1 removed,
The rear end of the guide 9 is connected to the rear end of the guide 9. By providing this, the hot air heater 6 is held at the center of the pipe 3.

To repair the pipe, first attach the repair sleeve 1 shown in FIG.
I decided. Since the Nli repair sleeve 1 described above is folded, the outer shell is reduced in diameter to φ, and the inner diameter of the pipe is φ. I was able to pass the elbow part of the A/S.

Next, move to the corrosion reducing part 5 shown in FIG.
1 transfer point” 1 or more d. It was heated to 75°C, which is 1 eave. Its culmination'
It was possible to restore the molded shape as shown in FIG. 2(a) and cover the surface of the corroded thinned area 5 before surgery. At that time, the four parts of the repair sleeve 1 are arranged f'(L,
The 1R agent bag 2 was torn, and the tangent was evenly dispersed between the sleeve and the blue distribution, and the two were able to be fixed together. After the replacement, the warm air heater 6 was pulled out from the pipe 3 by the pipe truck 10, and the replacement work was completed. In addition,
This repair sleeve is -1 (when it is returned to its molded shape, it will not deform only by 'l+l! If change) unless an external force is applied.

(Effects of the Invention) The present invention has the following advantages:1. By adopting the configuration described above, +l+
iJ If: Hli can be repaired to Yong & S on the seal of t'l, hli 4'6 quick outside, Sakurai ↑ 11 s
;j'+l Ensuring efficiency became the chief responsibility.

4. F of the illustrations! ? +11 Explanation Figure 1 is an explanatory diagram of a pipe repair method which is one specific example of the present invention.
Figure 2 is an explanatory diagram showing the relationship between changes in the shape of the repair sleeve, Figures 3 (a) and (b) are perspective views of the repair sleeve used in Figure 1, and Figures 4 to 6. Is it a conventional tube? +! It is an explanatory diagram of the i-repair method.

41

Claims (2)

[Claims] (1) In a pipe repair method in which a repair sleeve is transported to the area of piping to be repaired and the sleeve is integrated with the piping, the area to be repaired is coated with a shape memory polymer that has a glass transition point at a temperature higher than the operating temperature of the piping. A repair sleeve was prepared in which the shape was memorized by being molded according to the shape, and the sleeve was shrunk by heating to a temperature above the glass transition point and below the molding temperature, and the shrunken shape was maintained. The shrinking sleeve is then cooled to below the glass transition point and fixed, and then the contracted sleeve is transported to the above-mentioned area to be repaired, and then heated above the glass transition point and below the molding temperature to restore the memory. A pipe repair method characterized by restoring the molded shape and integrating it with the pipe. (2) By shrinking the sleeve molded to the shape of the area to be repaired into a star-shaped cross section, holding the adhesive in the recessed part, and restoring the molded shape of the sleeve at the area to be repaired,
The pipe repair method according to claim 1, characterized in that a uniform adhesive layer is formed at the interface between the sleeve and the pipe to integrate them.