JPH0722737B2 - Pipe inner surface lining repair method - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a repairing method for repairing a lining of an existing pipe, such as a gas pipe or a water pipe laid underground, in a buried state.

[Prior art]

In general, existing pipes laid underground such as gas pipes and water pipes may leak due to corrosion holes and loosening of joints with the passage of time. As a rehabilitation repair, the inner surface of the pipe is repaired by lining it with resin while it is buried. As such a repairing method, for example, as described in JP-A-63-65983, liquid resin is introduced into the pipe from one end opening portion of the existing pipe so as to fill the pipe, and before and after the resin plug. A repairing method has been proposed in which a pressure difference is generated in the pipe to cause the resin plug to flow toward the other opening side, and by this progress, a lining having a required film thickness is applied to the inner surface of the pipe. In the above-mentioned prior art, a launcher is connected to one end of an open existing pipe, a resin for lining is filled from a resin tank connected to the launcher to form a resin plug in the launcher, and the launcher is free to use. The pressurized gas supplied from the end side is supplied into the existing pipe. Then, the resin plug flows in the existing pipe under the pressure of the pressurized gas,
When the resin is consumed by the lining and blows through,
The number of times of introducing the resin plug from the resin tank through the launcher is repeated again to extend the lining region so that the resin lining can be applied to the entire length of the inner surface of the existing pipe over a predetermined length.

[Problems to be Solved by the Invention]

The problem here is that the amount of resin plug that can be introduced into the existing pipe at one time is substantially limited. This is determined by the viscosity of the resin used for lining, thixotropy, the thickness of the lining, and the pressure value of the pressurized gas. Moreover, the resin plug introduced into the existing pipe by the introduction from the next time has to maintain the same resin speed as that at the time of lining while sending it to the position where the line pressure is completed. Therefore, the time required for the first resin lining is
Even at t ₁ , the next time is t ₁ + t ₁ = 2t ₁ and the third time is t ₁ + t ₁ + t ₁ = 3t
As ₁ ..., each introduction number increases, since increasing the time required arithmetically, after all, the time T required until the lining completion of the required repair intervals, T = (n ²
+ N) / 2 · t ₁ . (However, n is the number of times the lining resin is introduced during this period.) The present invention has been made based on the above-mentioned circumstances, and by performing the conventional lining simultaneously from both end openings of the planned repair section, Moreover, it is an object of the present invention to provide a lining repairing method for the inner surface of the pipe, which can reduce the working time to about 1/4 as compared with the conventional method in which the working time is performed from one side of the opening.

[Means for Solving the Problems]

In order to achieve this object, in the present invention, the one end opening and the other end opening of the existing pipe to be lined are used as working inlets, and the resin plugs introduced into the pipe from both openings are repaired by a pressure difference pipe. In addition to allowing the fluid to flow toward the middle of the passage, an outlet passage serving as a work outlet is provided in the existing pipe at the intermediate position between the openings, and the air inside the pipe that has caused the resin plug to blow out from the outlet passage at the intermediate position, excess resin, It is characterized in that it is constructed so as to discharge pressurized gas and the like.

[Action]

According to the above repair method, when the resin plug is introduced from the openings at both ends of the existing pipe, the air in the pipe in the repair section is taken out through the discharge passage at the intermediate point, and as in the case of the conventional lining. Blow-through of the resin plug can be realized through the intermediate lead-out passage. In this case, the substantial working time can be shortened to about 1/4 of the working time of the conventional one-way repair method,
The lining repair work is greatly streamlined.

【Example】

An embodiment of the present invention will be specifically described below with reference to the drawings. In the figure, reference numeral 1 is a resin supply device used in the repairing method of the present invention, and 2 is an additive used when the lining resin supplied from the resin supply device 1 to the repaired part of the existing pipe is made to flow with a pressurized gas. It is a pressurized gas supply device. The resin supply device 1 includes a resin injector 3, a supply pipe 4 that communicates with the bottom of the resin injector 3, and a launcher 6 that communicates with the supply pipe 4 via an electromagnetic on-off valve 5. When the electromagnetic on-off valve 5 is open, the lining resin in the resin injector 3 is supplied and filled in the launcher 6, and the resin plug E is formed in the launcher 6. The resin injector 3 is provided with a plunger 3a,
Pressurized gas is supplied to the top portion by means such as that described later so that the resin can be extruded. The lining resin with which the launcher 6 is filled is, for example, a room temperature two-liquid curing type resin prepared by mixing a main agent and a curing agent,
Of these, the main component is a composition whose main component is unsaturated polyester resin, vinyl ester resin, epoxy resin, urethane resin, etc., and pigments, thixotropic agents, etc. are added to this to have thixotropic properties (eg, 250,000). ~ 300,000cp
TI value is 6 with s. On the other hand, the pressurized gas supply device 2 includes the compressor 7, the air tank 8, the flow rate adjusting valves 9 and 10, and the launcher 6 described above.
The electromagnetic on-off valve 12 is attached to the gas supply pipe 11 connected to the end of, and flowmeters 13 and 14 and pressure gauges 15 and 16 are provided corresponding to the flow rate adjusting valves 9 and 10. Further, if necessary, a three-way switching valve 17 is provided on the outlet side of the compressor 7 so that the pressurized gas can be branched to the pipe line 18, and the resin injection described above can be performed via the pipe line 18 and the flow rate adjusting valve 19. It communicates with the top of the vessel 3. The output information from the flowmeters 13 and 14 and the pressure gauges 15 and 16 is received, and calculation is performed according to the required program,
A control unit 20 for adjusting and controlling 9, 10 is provided in the pressurized gas supply device 2. In the control unit 20, the amount of resin to be filled into the launcher 6 is calculated from the adjustment of the opening degree of the flow rate adjusting valve 19 and the opening time of the electromagnetic on-off valve 5, and the amount is stored in the memory and the electromagnetic on-off valve 5 is also stored.
Of the resin flow rate V for achieving the resin lining with a predetermined film thickness from the opening time of the, and the output information of the flowmeters 13 and 14 and the pressure gauges 15 and 16 thereafter every moment, and the speed is calculated. It functions to control the opening degree of the flow rate adjusting valves 9 and 10 so as to maintain it. On the other hand, the existing pipes to be repaired with the lining according to the present invention are the branch pipe A (or the main pipe) buried underground (under the road) and the service pipe B connected to the meters with one end protruding to the ground. The service pipe B is branched from the branch pipe A. Then, the lining repair is first performed on the service pipe B and then on the branch pipe A, but prior to that, preparations for the following repairs are made. That is, the branch pipe A is divided into repair sections of a predetermined length and both ends thereof are opened. Therefore, vertical shafts C and D as shown in FIG. 2 are formed at the corresponding places, and the end of the branch pipe A is cut there by cutting. Open. A shaft F is also formed at the midpoint M of the repair section of the branch pipe A, and a through hole A'is formed in the upper surface of the branch pipe A exposed in the shaft F. Then, the conduit 27 is communicated with here, and is connected to the receiver 28. To the receiver 28, an exhaust valve 29 and a receiver tank 30 for receiving the resin contained in the receiver 28 are connected. A clamp 31 is used in this embodiment for connecting the pipe line 27. In this clamp 31, half-divided clamp pieces 31a, 31b are applied from above and below the branch pipe A and tightened with bolts 31c so that the branch pipe A can be airtightly held from above and below via a packing 32, and the clamp piece 31a The joint 31d provided corresponds to the through hole A '. By connecting the pipe 31 to the pipe 27 at the joint 31d, the branch pipe A and the pipe 27 are communicated with each other at the intermediate point M (a tap is made in the through hole A'to connect the pipe 27). , The nipple may be screwed together). Further, for the service pipe B communicating with the branch pipe A, the meters are removed and the ground end is opened. Then, pressurized air is passed through the branch pipe A and the supply pipe B to remove dust inside. In the repair work, first, the launcher 6 is connected to the open end of the service pipe B, the electromagnetic opening / closing valve 5 is opened, and the lining resin is supplied and filled into the launcher 6 by the pressurized gas from the resin injector 3. A resin plug is formed so as to fill the inside of 6. Then, the electromagnetic on-off valve 5 is closed, and the electromagnetic on-off valve 12 is opened to supply the regulated pressurized gas into the launcher 6, thereby giving fluidity to the resin plug by the pressure difference generated before and after the resin plug. The resin plug is sent to the inner pipe B to form a lining film having a predetermined thickness on the inner surface of the pipe. At this time, in the control unit 20, the opening degree of the resin flow rate adjusting valves 9 and 10 is adjusted. In this case, the calculation basis of the control unit 20 depends on the following formula. First, assuming that the amount Q ₁ of pressurized gas flowing into the supply pipe B and the pressure P ₁ (eg, 0.6 kg / cm ² ) are π / 4 · D ² · l ₁ · P ₁ = Q ₁ · P ₀ Since there is a relation of (1), if Q ₁ , P ₀ , P ₁ at the time T _{1 when} the feeding of the resin plug by the pressurized gas is started is measured, then l ₁ can be known from the equation (1). The amount Q _{1 of} gas flowing into the service pipe B is obtained by the difference between the measured values F ₁ and F ₂ of the flowmeters 13 and 14. In this case, if a mass flowmeter is used for the flowmeters 13 and 14, there is no influence of the temperature of the gas, and therefore the calculation is easy. Also here, l ₁ is the position of the resin plug at time T ₁ ,
P ₀ and P ₁ are measured values of the pressure gauges 15 and 16, and D is a lining inner diameter of the service pipe B. Similarly, if the position of the resin plug obtained by measuring and calculating the pressure P ₂ and the inflow amount Q ₂ at time T ₂ is l ₂ , the flow velocity V of the resin plug is V = Δl / Δt Become. However, Δl = l ₂ −l ₁ and Δt = T ₂ −T ₁ . Therefore, the predetermined time interval Δt is set to the control unit 20.
Set with the clock of the internal oscillator, and each time, the flowmeter 13,1
The amount of inflowing gas flowing into the pipe from 4 and the respective pressures from the pressure gauges 15 and 16 are measured, and the flow rate adjusting valves 9 and 10 are set so that the instantaneous resin flow velocity V is maintained at a constant value. Control it. In the supply pipe B, the length of the resin plug is reduced because it is consumed for lining the inner surface of the pipe, but the control unit 20 calculates the amount of resin consumed over time, which corresponds to this. Since the pressure of the pressing gas drops substantially linearly (see FIG. 4), the flow velocity of the resin plug can be maintained at a constant value. If the resin of the resin plug is consumed before the resin lining on the inner surface of the supply pipe B is completed over the entire length of the pipe, the pressurized gas pressing the resin plug at that time blows through the supply pipe B. , It drops to the atmospheric pressure of the branch pipe A. Since such a pressure change occurs abruptly, it is checked on the control unit 20 side and it is determined that the resin lining for this time has ended.
The inflow amount Q of the gas supplied to, the length l to the position where the resin lining is finished, the elapsed time t _0, etc. are stored in the memory, and the electromagnetic opening / closing valve 12 is closed. Next, in the control unit 20, the solenoid opening / closing valve 5,
The flow rate adjusting valve 19 is opened, and the lining resin is supplied from the resin injector 3 into the launcher 6 and filled therein to form a predetermined amount of resin plug in the launcher 6. Then, the electromagnetic opening / closing valve 5 and the flow rate adjusting valve 19 are closed, the electromagnetic opening / closing valve 12 is opened, and the inner pipe B is lined while controlling the resin plug E to the speed V again as described above. At this time, as long as the speed V is maintained, the length of the resin plug, in other words, the amount of resin, does not change while the lining resin plug E passes through the area that has been lined last time. The pressure of the pressed gas is also maintained at a substantially constant value. However, after the resin plug E reaches the position where the inner pipe B is not yet lined, the resin is consumed by the lining as described above, the length of the resin plug E is reduced, and the pressure of the pressing gas is also reduced. The lining proceeds while gradually decreasing.
Then, the resin plug length becomes approximately 0, and the elapsed time until the pressure gas blows through and falls to the atmospheric pressure becomes approximately 2t ₀ ,
The length to the end of the lining is also about 2l. In this way, the lining region is sequentially extended while the lining is repeated by the introduction of the resin plug and the flow of the resin plug by the pressurized gas. When the lining of the supply pipe B is completed and the length of the resin plug still remains and reaches the connection portion (branch point) with the branch pipe A, the resin plug E flows into the branch pipe A and presses the resin plug E. The pressurized gas that has been blown blows into the branch pipe A. Therefore, the measured value of the pressure gauge 16 drops sharply to almost atmospheric pressure. This is judged by the control unit 20. This is the expected elapsed time (n ×
t) (where n is the number of times the resin is introduced, t is the length of time until the lining of the resin plug is completed once) (n-1)
At t + t '(however, t'<t), it is judged whether or not the rapid pressure drop as described above is brought. That is, it is determined that the resin plug has reached the branch pipe A based on the sudden decrease in the pressing force and the difference between the actual elapsed time and the predicted elapsed time, and the lining repair for the corresponding supply pipe B is completed. . If t'≈t, there is a problem of measurement error.
Furthermore, it is advisable to introduce the resin once more and measure the time required to reach the branch pipe A. This error range may be preset by the control unit 20. That is, the control unit 20 commands the resin introduction again if it is within the error range, and outputs the command of termination if it is not within the error range. If the amount of resin remaining in the branch pipe A is unknown when the branch pipe A is lined later, the resin plug length in the lining process of the branch pipe A changes, so that the residual resin in the branch pipe A is not Either remove it prior to lining, or store this residual resin in the memory of the control unit 20 and place a resin plug at the branch point (the connection point with the inner pipe B in the branch pipe A) when lining the branch pipe A. When the temperature reaches, the above control unit will be adjusted so that it will be corrected to the length of the resin plug including the residual resin amount.
You may calculate by 20. After the resin lining for each inner pipe B branched from the branch pipe A in the repair section in this way is completed, as shown in FIG. 5, the inner end of the inner pipe B is made of a transparent pipe or the like. Connect the receiver 21 that A cylinder 23 of compressed gas such as compressed air is connected to the receiver 21 via a flow rate adjusting valve 22, and a throttle valve 2 is connected to a branch portion 21a of the receiver 21.
4 are connected, and a pressure gauge 25 and a flow meter 26 are provided. In this state, the branch pipe A is then repaired. As shown in FIG. 6, the repair work for the branch pipe A is performed by connecting the launchers 6, 6 with matching dimensions to the opening portions at both ends of the branch pipe A, and providing the resin supply devices 1, 1 for the respective launchers 6, 6.
Therefore, as in the case of the service pipe B, the repair resin is supplied and filled into the pipe in the form of a plug. In the repair work for this branch pipe A, resin plugs are individually introduced from the both end openings of the branch pipe A through the launchers 6 and 6, and the inside of the branch pipe A is directed from the both end openings to the intermediate point M of the repair section. The resin lining on the pipe inner surface with respect to the branch pipe A is realized by the progress of the flow. In addition, in the illustration of FIG. 6, the branch pipes A on the left and right with the middle point M as a boundary are shown with the service pipe B on only one side, and the service pipe B on the other side is not shown. It goes without saying that the left and right branch pipes A having the middle point M as a boundary are normally branched with the number of supply pipes B according to the laying condition of the pipeline. When repairing the branch pipe A, pressurized gas is supplied from the cylinder 23 to the service pipe B branched from the left and right branch pipes A via the above-described flow rate adjusting valve 22, and the throttle valve 24 is closed at this time. ing. As the pressurized gas, for example, assuming that the pressure of the pressurized gas applied to the resin plug E in the branch pipe A is 1.5 kg / cm ² , the pressure in the service pipe B is slightly lower than that of, for example, 1.3 kg / cm ² . Hold the pressure. in this case,
The pressurized gas that presses the resin plug E in the branch pipe A is
As described above, when the resin is consumed for lining and the resin plug length becomes shorter, the resin is gradually lowered.Therefore, based on this information, the flow rate adjusting valve 22 is adjusted by the control unit 20 so that the pressure difference is, for example, −0.2 kg / It is recommended to control so as to keep it at cm ² . As a result, as shown in FIG.
When the resin plug E reaches the connection point between the branch pipe A and the service pipe B in the process of lining the service pipe A up to, the resin amount (predetermined amount) corresponding to the pressure difference enters the service pipe B. At this time, the pressurized gas in the supply pipe B is compressed by the invading resin E'and the pressure rises (corresponding to the pressure of the pressurized gas for pressing on the branch pipe A side), which is detected by the pressure gauge 25. Then, the control unit 20 analyzes it and issues a command to close the flow rate adjusting valve 22. Therefore, the resin is consumed for the lining in the branch pipe A, and the invading resin is retained in the service pipe B until the pressurized resin is blown out because the resin plug disappears (see FIG. 8). ), When blown through, the internal pressure in the branch pipe A drops to atmospheric pressure, so that the invading resin is discharged into the branch pipe A at the gas pressure on the side of the service pipe B and left in the branch pipe A (9th). See figure). In the control unit 20, the amount of resin that has penetrated into the service pipe B is calculated from the gas pressure difference at that time, the inner diameter of the service pipe B, etc., and passes through the connection point (branch portion) with the service pipe B. The subsequent resin plug length is corrected so that the speed V of the resin plug is kept constant. When the invading resin is discharged into the branch pipe A from the supply pipe B, the control unit 20 detects this by a decrease in the pressure indicated by the pressure gauge 25, opens the flow rate adjusting valve 22 again, and pressurizes the gas from the cylinder 23. Is supplied into the supply pipe B at a required pressure. Therefore, when the next resin plug is introduced into the branch pipe A and passes through the connection point with the corresponding inner pipe B, the same amount of resin invades into the inner pipe B again, so that the resin plug reaches the unlined area. The length of the resin plug in the branch pipe A does not change in the process of being sent by pressurized gas. In this way, for the branch pipe A in the repair section, the resin plug introduced into the pipe from the openings at both ends thereof is introduced, the flow is advanced by the pressure difference due to the pressurized gas, and the lining is repeatedly executed.
Finally, the lining work is continued until the resin plug is discharged from the outlet pipe 27 to the receiver 28 through the through hole A ′ provided at the intermediate point M of the branch pipe A. And receiver
When the resin plug reaches 28, the resin will
Then, the pressurized gas blows through and drops to the atmospheric pressure, and the control unit 20 detects the end point of the lining operation for the branch pipe A. Finally, a required amount of the resin plug is introduced into the pipe through the openings at both ends of the branch pipe A, and is made to flow with pressurized gas. Finally, a fixed amount of the resin is delivered to the supply pipe B in the same manner as described above. invade. At this time, the control unit 20 detects the resin intrusion into the service pipe B with the pressure gauge 25, and closes the flow rate adjusting valve 22 and then a predetermined time elapses, that is, the resin plug E in the branch pipe A. After passing through the connection point with the service pipe B, the throttle valve 24 is controlled to open at a predetermined opening. As a result, the pressurized gas on the open end side of the service pipe B is gradually released into the atmosphere through the throttle valve 24, and the invading resin is pushed by the pressurized gas in the branch pipe A to serve the service pipe. It moves inside B and is consumed as a lining layer in this process, or is pressed as it is and reaches the receiver 21. In this process, the flow meter 26 measures the discharge amount of the pressurized gas, and the control unit 20 corrects the inflow amount of the pressurized gas supplied to the branch pipe A side in consideration of the discharge amount. And receiver 21
The throttle valve 24 is closed at the stage where the invading resin has reached the position or when the pressurized gas on the side of the branch pipe A has blown into the receiver 21 (when the invading resin is consumed as the lining layer). In this way, the resin plug that has passed through the branch pipe A after the entry resin is cleaned up in the inner pipe B communicating with the branch pipe A one after another passes through the pipe 27 from the through hole A ′ at the intermediate point M. It is then discharged to the receiver 28, which completes the finishing lining (see FIG. 10). After this, the pipe line 27 is removed, and a blind plug or the like is screwed on the joint 31d, for example, to substantially block the through hole A'in the branch pipe A from the outside. In the above embodiment, the resin is introduced into the inner pipe B from the outer open end thereof to achieve the resin lining of the inner pipe B first.
At the same time, the resin lining of the inner pipe B may be performed in parallel with the resin lining of the branch pipe A, for example, by lining with the resin penetrating into the inner pipe B. In this case, the control unit 20 may control the distribution of the amount of resin from the branch pipe A to the supply pipe B and the securing of the resin feed speed V by the pressurized gas. Further, in this case, the receiver 21 and the throttle valve 24 as described above are provided at the open end of the service pipe B.
Etc. should be provided. In this way, when the resin plug is introduced from both end openings of the branch pipe A and the inner surface of the pipe is lined by pressing with the pressurized gas, when the time t for one lining and the length l are set, Compared with the method of introducing the lining resin from one end to the other end of A in one direction and pressing with a pressurized gas, the time required for lining the same length L = nl may be approximately one fourth. And saves a lot of work time (ie T = n ² + from one end)
n) / 2 · t, but T from both ends (invention)
= A ^{n 2/4 + n / 2} · t).

【The invention's effect】

According to the present invention, as described in detail above, the resin is introduced into the existing pipe in the repair section from both end openings in a plug shape, and from the midpoint of the repair section, the blown-in pipe air,
Since the lining work is performed so as to discharge the surplus resin and the pressurized gas, the working time is about one-fourth as compared with the conventional method in which the lining work is performed through the one-way hole, and the lining is performed. The excellent effect that the work efficiency of repair work can be greatly improved is obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a condition of an existing pipe to be repaired, FIG. 3 is an explanatory diagram showing a resin lining condition of a service pipe, and FIG. FIG. 5 is a time chart showing the repeated state of resin lining, and FIG. 5 is an explanatory view showing means for preventing invading resin at the open end of the service pipe.
FIG. 6 is an explanatory view showing a resin lining state of a branch pipe, and FIG.
FIG. 8 is an explanatory view showing a situation when a resin plug reaches a branch portion to a service pipe in a branch pipe, FIG. 8 is an explanatory view showing a situation after the resin plug has passed through the branch portion, and FIG. FIG. 10 is an explanatory view showing a situation when the pressurized gas blows through the branch pipe, and FIG. 10 is an explanatory view showing a situation at the time of finishing lining. 1 ... Resin supply device, 2 ... Pressurized gas supply device, 5 ...
Electromagnetic on-off valve, 6 ... Launcher, 7 ... Compressor, 8
...... Air tank, 9,10 ...... Flow control valve, 12 ...... Electromagnetic on-off valve, 13,14 ...... Flow meter, 15,16 ...... Pressure gauge, 19 ...... Flow control valve, 20 ...... Control unit, 21 ...... Receiver,
22 …… Flow control valve, 23 …… Cylinder, 24 …… Throttle valve, 25…
… Pressure gauge, 26 …… Flowmeter, 27 …… Pipe line, 28 …… Receiver, A …… Branch pipe, B …… Service pipe, A ′ …… Through hole, M ……
Midpoint.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masato Shinozaki Four stock companies, 3-18, Daiko City, Kanagawa Prefecture

Claims (1)

[Claims] 1. A liquid resin is introduced into a pipe from an opening at one end so as to fill the pipe, and a pressure difference is generated in the pipe before and after the resin plug to allow the resin plug to flow toward the opening at the other end. , In the repairing method of constructing a lining of the required film thickness on the inner surface of the pipe by the progress of this resin plug, one end opening and the other end opening of the existing pipe to be lined are used as working inlets, and the inside of the pipe is opened from both openings. The resin plug introduced is caused to flow toward the middle of the pipeline in the repair section due to the above pressure difference, and a discharge passage serving as a work outlet is provided in the existing pipe at the intermediate position of both openings, and the discharge passage at the intermediate position is provided. A lining repairing method for the inner surface of the pipe, which is characterized in that it is constructed so that the air in the pipe that has blown through the resin plug, excess resin, and pressurized gas are discharged.