JPS6377579A - Method for lining and repairing inside surface of pipe - Google Patents

Abstract

PURPOSE:To permit formation of a coated film having a uniform film thickness in spite of a decrease in a resin amt. by controlling a blast controller by the signals detecting the pressure in the pipe on a discharge side and a discharge air quantity in such a manner that the constant flowing speed of the lining resin in the pipe is maintained. CONSTITUTION:A launcher 2 having the blast controller 7 provided with a throttle valve 12 for controlling the flow rate of the pneumatic air to be introduced into the pipe and a stop valve 14, etc. is connected to the end of the pipe on the side where a packing resin is to be fed. A receiver 3 provided with a pressure gage 20 and flow meter 21, etc., for detecting the pressure in the pipe on the discharge side and the discharge air quantity according to the flow of the packed resin in the pipe is connected to the other end of the pipe on the outlet side. The blast controller 7 is controlled by the signals detecting the pressure in the pipe on the discharge side and the discharge air quantity in such a manner that the constant flowing speed of the lining resin is maintained. As a result, the lining coated film having the uniform film thickness is formed in spite of a decrease in the resin amt.

Description

[Detailed description of the invention]

[Industrial Application Field 1] The present invention is applicable to existing pipes such as gas pipes and water pipes installed underground, especially small-diameter existing pipes called supply pipes and branch pipes. This invention relates to a method for repairing the inner surface of a pipe by forming a resin lining film in its original state. [Prior Art] Existing pipes such as gas pipes and water pipes that are installed underground generally develop corrosion holes and cracks in the pipes over time, which may cause leakage, so leakage repair is necessary. Alternatively, for preventive maintenance, repairs such as forming a resin lining film on the inner surface of the pipe are carried out while the pipe is still in its installed state. Conventionally, as a repair method for existing piping of small diameter,
- As seen in Japanese Patent Publication No. 39274, a resin is mixed with a forced air flow, atomized, and then forced into a pipe and lining it by adhering to or stretching the inner wall surface (vapor phase method). As seen in Publication No. 55-44320, a method in which the resin is moved in a liquid state into the pipe by a VIG, and the resin is forced to flow backward from the circumference of the VIG and adhere to the inner surface of the pipe (liquid phase method/VIG transfer method) etc. are known. In the case of repair using the above-mentioned "liquid phase method" or "VIG transfer method", since the liquid resin is moved inside the pipe by the VIG, small diameter supply pipes such as supply pipes with diameter changing parts or curved pipe parts in the middle of the pipe, etc. When repairing pipes, there is an inconvenience that the vig gets caught in the diameter change part or bent pipe part of the pipe, making it impossible to flow or repair, so conventionally, when repairing small diameter pipes, Generally, lining repair using the above-mentioned "vapor phase method" is mainstream.

[Problems to be solved by the invention]

However, in the case of the conventional lining method using the gas phase method,
There were problems as described below. (1) First, in the conventional lining method using the "vapor phase method", the resin must be conveyed or stretched for a long time within a repair section of a predetermined length using air flow velocity and air viscosity, so the resin viscosity is low. Viscosity (e.g. 15,0
Therefore, the lining coating film attached to the inner surface of the tube is thin, with a thickness of 0.5 mm or less, and the lining coating film is In addition, the film thickness becomes uneven, with the inner wall of the pipe being thicker on the lower surface and thinner on the upper surface.In addition, in curved pipe parts such as elbows, the film thickness is extremely thin on the outer curved surface of the pipe, where corrosion is likely to occur. There were problems such as unavoidable phenomena. (2) In addition, in the conventional lining method using the "vapor phase method," in order to increase the film thickness and make it as uniform as possible, it is necessary to use a high-viscosity resin. To send W1 into the pipe of the length repair section,
Since a large amount of air volume and high-speed airflow are required, a pressure of 2 kg/cm2 or more is generally required, so equipment (such as compressors) becomes larger.
In addition to higher equipment costs, there were also problems such as the equipment being unable to be transported to some work locations and repair work being impossible, and the noise being loud, which significantly worsened the work environment in residential areas. . Furthermore, in the conventional lining method using the "vapor phase method," the pressurized airflow of resin flows while directly contacting the inner wall surface of the pipe, and pressurized air of 2k (+/Cl112 or more) is added to the inside of the pipe. For example, when a pinhole-like corrosion hole occurs in a pipe, a blow-out phenomenon occurs outside the pipe from the corrosion hole, and not only is it impossible to expect the corrosion hole to be reliably filled, but the corrosion hole is There were also problems such as the phenomenon of further expansion and damage to the pipe. (4) Furthermore, in the conventional lining method using the "vapor phase method", the resin oil filled inside the pipe decreases as it flows. However, if the flow rate of the compressed air pressing the filled resin is constant, the flow rate of the filled resin gradually increases toward the rear, resulting in a problem that a uniform lining coating film cannot be formed.

[Means to solve the problem]

The purpose of the present invention is to provide a new method for repairing the lining of the inner surface of pipes, which has been proposed to solve the above-mentioned problems.To achieve this purpose, the repair method according to the present invention is Fill the pipe at one end with resin in a liquid state so as to fill and close the pipe from its opening over the required length; Based on the related conditions, a required static pressure is applied to the rear end surface of the filled resin so that it flows in a nodular shape within the pipe at a set speed necessary to form the required film thickness on the inner surface of the pipe, thereby making the resin mass fluid. and when the resin group flows in the pipe, the above-mentioned pressing force is attenuated in accordance with the reduction in the 84 fat suspension due to the formation of the coating film, so that the flow rate of the resin group in the pipe is kept approximately constant. (2) A launcher having an air blowing control device equipped with a throttle valve, an on-off valve, etc. for controlling the air flow rate of the pressurized air introduced into the pipe at the end of the injection side pipe of the filled resin; θ9 Connect a receiver equipped with a pressure gauge J3 and a flow meter to detect the pressure inside the discharge side pipe and the amount of discharged air that change as the filled resin flows in the pipe to the other outlet side pipe end, and (to) the above The present invention is characterized in that the air blowing control device is controlled to maintain a constant flow rate of the lining resin in the pipe based on a signal that detects the pressure inside the discharge side pipe and the amount of discharged air. In this type of repair method, the soldering resin introduced into the pipe is pushed by static pressure and flows inside the pipe, and during this flow, the resin adheres to the wall surface as it flows while contacting the inner surface of the pipe. remains on the inner surface of the tube, and this residual resin forms a lining coating on the inner surface of the tube. In the formation of such a coating film, as is clear from the experimental results described below, the amount of resin remaining in contact with the inner surface of the tube (coating film thickness)
can be freely controlled by selecting the resin flow rate, resin viscosity, etc., so the thickness of the lining coating can be adjusted to the desired thickness (
The film thickness can be adjusted to between 1mm and 10mm (Pi2 degrees), and the coating film that remains after the resin passes through is caused by the pressing force that acts on the rear end surface when the lining resin flows inside the pipe, and the pressure applied to the entire end surface. Since it is evenly distributed, it is possible to form a coating film with a uniform thickness all over the circumferential direction of the tube. Furthermore, a launcher connected to the injection side tube end of the filled resin fills the resin over the required length using thixotropic resin, and when external force is applied to this resin, its structure is destroyed and softens. The initial pressing force that gives fluidity to the filled resin is set high on a part of the launcher, and once it flows, it forms a coating film inside the pipe while flowing. Since the pressing force can be reduced and the air agitation required can be reduced, equipment such as compressors can be significantly downsized, and the compressed air of the resin can be kept at a constant low pressure (static pressure). Moreover, since the air flow flows through the lining treated pipe after the coating film is formed by the residual resin and does not come into direct contact with the inner wall surface of the pipe itself due to the interposition of the coating film, blowing from corrosion holes is guaranteed. It becomes possible to prevent this.

[Embodiments] Examples according to the present invention will be described below with reference to the attached drawings. In the drawings, FIG. 1 schematically shows an example of the repair method according to the present invention, and reference numeral 1 indicates an existing pipe to be repaired. The existing piping 1 is an existing piping such as a gas pipe or water pipe installed underground or inside a building, and in particular, the existing piping to be supplemented by the present invention is a gas pipe. The target is existing pipes with relatively small pipe diameters, generally called supply pipes with a diameter of about 15 to 32 m wide, or branch pipes with a diameter of about 40 to 100 mm. This existing piping 1 is divided into repair sections of a predetermined length when repairing, and a launcher 2 that extends the predetermined length is connected to the opening at one end, and the opening at the other end is A receiver 3 through which the inside can be seen is connected. A resin injector 4 is connected to the launcher 2 via an on-off solenoid valve 5 which is a resin supply means.
The liquid lining resin A is introduced into the launcher 2 so as to fill and close the pipe for a required length. The lining resin A used here is a two-component curing resin at room temperature, which is a mixture of a main resin and a curing agent, and has thixotropic properties. Note that the resin injector 4 may be supplied with a resin in which the main resin and curing agent are mixed in advance using an air pressurized injector, or the main resin and curing agent may be pumped using separate pumps and a static mixer may be used in the process. It is also possible to supply a mixture of rain sounds. Further, a small compressor 6 is connected to the tip of the launcher 2 via a blower f, II control device 7, and the flow rate of compressed air from the compressor 6 is regulated by a blower control device 7. It is designed to be introduced into the interior and fed into the existing piping 1. Note that the compressed air from the compressor 6 is cut off by a solenoid valve 8 which is linked to the blower control device 7. The lining resin 8 is also introduced into the resin injector 4 via the governor 9, and is opened via a pressurized sliding plate 10 provided in the resin injector 4 in conjunction with the blower control device 7. A predetermined amount of liquid is extruded and filled into the launcher 2 under a constant pressure from the open/close solenoid valve 5. Further, the above-mentioned air blow control all device 7 includes a flow rate control section 13 equipped with a filter 11 that cleans the pressurized air from the combrella V6, and a throttle valve 12 that controls the flow rate of the pressurized air by υ1go.
and an on-off valve 14 for controlling supply and cutoff of pressurized air, and a pressure gauge 15 in the air supply path, and an on-off valve 14. Relief valve 18. The flow rate controller 16 controls the throttle valve 12 and the like. This flow rate controller 1G receives signals such as the flow rate of resin in a pipe, which will be described later, through an antenna 17, and also detects air pressure through a pressure gauge 15 and receives signals from a throttle valve 12. Relief valve 18. It controls the on-off valve 14. On the other hand, the receiver 3 connected to the other opening of the twin piping 1 has a shutoff valve 28. Pressure gauge 20. A flow meter 21, etc. is connected, and the pressure gauge 20.1%Hf14t21 detects the pressure inside the discharge side pipe and the discharge air m from the pipe, which change as the lining resin A flows, and by these detections, The flow velocity of the lining resin Δ in the pipe is detected, and this detection signal is sent to the transmitter 22. The signal is transmitted to the antenna 17 on the starting end side via the antenna 25, and is controlled by the air blow control Il device 7 described above. Furthermore, a cyclone type resin separation hopper 26 equipped with an air discharge valve 27 is connected to the end of the receiver 3, and when the lining resin A reaches the receiver 3 whose interior can be seen through, it is closed in advance. By opening the air discharge valve 27 and closing the cutoff valve 28, the remaining resin can be collected into the resin separation hopper 26. Next, to explain the work process of repair work using the above-mentioned device, first, open the on-off solenoid valve 5 and inject a predetermined amount of lining resin A in liquid form from the resin injector 4 into the launcher 2 on the starting end side. . The resin Δ is injected so that the lining resin A is filled and occluded over a predetermined length into the pipeline on the starting end side of the existing piping 1 from the inside of the launch 1--2. Next, when the filling of the resin A is completed, the on-off solenoid valve 5 is closed, and the on-off valve 14 on the feed Ill system side is operated to send the pressurized air from the compressor G to the end of the launcher 2 while controlling the flow rate with the throttle valve 12. into the pipe. As a result, the pressurized air acts to compress the rear end surface of the filled resin A from the rear, and the static pressure (compression force) imparts fluidity to the lining resin A, and the lining resin △ becomes columnar. In this state, the liquid flows from inside the lunch t-2 into the existing piping 1, and flows through the existing piping 1 as a group. The compressive pressure applied to the resin A at this time is such that the initial pressure to impart fluidity to the resin is approximately 1.5 kg/cm2 or less relative to atmospheric pressure, and the When A flows through the existing piping 1, its pressing force is regulated by the relief valve 18 to reduce the pressure to approximately 0.6 kg/cm2 or less relative to atmospheric pressure. As the resin △ flows, the adhesive force against the wall surface as it flows while contacting the inner surface of the tube causes the resin △ to remain on the inner surface of the tube as it progresses, and after passing through the resin group, this residual resin A lining coating film of the required thickness is formed on the inner surface of the tube. According to the experiment, resin A filled in the existing pipe 1
When the entire pipe is run from the rear by static compression pressure, the shape of the resin end face on the pressurizing side where compression pressure is applied is the pressure force a shown in Fig. 2 and the adhesion force to the inner wall surface. According to the influence coefficient, due to the resultant force with the resin shear stress C, when the resin flows in the pipe, it travels in a shape as shown in Fig. S. From this running state, if the compressive force a from the rear against the resin end face is increased and the running speed V of the resin A is increased, the resin end face shape becomes a bullet shape as shown in FIG. 4, and on the other hand, It has been found from the results of experiments that when the compressive pressing force a is reduced and the traveling speed V of the resin Δ is slowed, the end face shape of the resin becomes nearly vertical as shown in FIG. Also, according to experiments, the viscosity CpS of resin A and the running speed V
The relationship between the formed lining film thickness t is as follows: ■ When the traveling speed V is constant, the resin viscosity (5000
The higher the viscosity (0 cps to 500,000 cps), the thinner the lining coating film will be, and the lower the viscosity, the thicker the lining coating film will be. ■ Also, if the resin viscosity is constant, the traveling speed of the resin V
It was found that the faster the travel speed, the thicker the film, and conversely, the slower the travel speed, the thinner the film. According to the above experimental results, <i> First, when the traveling speed V to the resin is kept constant and the resin viscosity is changed, the lower the resin viscosity, the more the end face shape of the resin will be bullet-shaped as shown in Figure 4. Therefore, the film thickness is thicker, and the higher the viscosity, the more vertical the end face shape as shown in FIG. 5 is, and the film thickness is thinner. 6i) In addition, when the resin viscosity is kept constant, when the compression pressure is increased and the traveling speed of the resin A is increased, the end face shape of the resin becomes bullet-shaped as shown in FIG. 4, and the film thickness is thick.
When the compression pressure is lowered and the running speed is lowered, the end face shape of the resin becomes a vertical end face shape as shown in FIG. 5, and the film thickness becomes thinner. In other words, in terms of the relationship between resin viscosity and running speed (■), if the resin is flowed and run so that the end face shape of the resin becomes a bullet shape as shown in Fig. 4, the film thickness will be thick. When the resin A is fluidized and run so that the end face shape is nearly vertical as shown in the figure, the film thickness becomes thin. To consider this theoretically, P in Figures 4 and 5 is
The component force relationship of pressure at points t and Pt is that the end face shape is a bullet shape (
4), as shown in FIG. 6, the pressing force acts in the RO force direction perpendicular to the tangential direction S1 of the resin spherical surface, and the component force of that force is the component force R1 that causes the resin to flow. , and a component force R2 that presses the resin against the inner wall of the pipe. On the other hand, when the end face shape of the resin is vertical (as shown in Figure 5), as shown in Figure 7, P? The pressing force acts in the Q○ force direction perpendicular to the tangential direction S2 of the resin spherical surface, and the component force is divided into a component force Q1 that causes the resin to flow and travel and a component force Q1 that presses the resin against the inner wall of the pipe. When comparing the component forces R1 and Qt that cause the resin to flow and travel as described above and the component forces Rz and Qz that press the resin against the inner wall of the pipe, the bullet-shaped one shown in Fig. 4 has a component force R that causes the resin to flow and travel.
1 is much smaller than the component force Q1 corresponding to that of the vertical type shown in Fig. 5, and the component force R1 is balanced with the sum of the influence coefficients of the resin shear stress and the adhesive force, so the resin A has a thickness It is understood that it remains on the inner wall of the tube as a film. From the above results, the shape of the end face on the pressure side of resin A is bullet-shaped (
If the lining resin A is fluidized so that the thickness of the lining coating film becomes J'7 (as shown in Figure 4), the lining coating film will have a nearly vertical end face shape (as shown in Figure 5). It has been experimentally and theoretically confirmed that if the lining resin △ is flow-travelled, the lining coating film will be formed into a thin film.
Filled resin length,! The results shown in Table 1 were obtained regarding the relationship between the resin running speed, initial pressing force, and film thickness. Based on the relationships among the pipe diameter, resin viscosity, and filled resin length shown in Table 1 above, it is clear that the inner surface of the pipe contains, for example, NO2. When trying to form a film with a thickness of 0 mm, the resin flowed into the tube was 9 am/
It is understood that it is necessary to run at sac, and by appropriately selecting the running speed of the resin, the thickness of the lining coating film formed can be freely controlled. Therefore, in the repair method according to the present invention, first, the thickness of the lining coating film to be formed on the inner surface of the target existing pipe 1 is selected, and the selection of the film thickness is Based on this, the flow rate of resin A necessary to form the desired film thickness is set based on the repair-related conditions such as the tube of the pipe to be repaired, the viscosity of the resin used, and the pressure of the filled resin. The forward air from the compressor 6 is controlled to apply a required static pressure to the rear end surface of the filled resin so that the lining resin flows through the pipe at a flow rate that is as high as the flow rate. In this case, the resin A used is a thixotropic resin as mentioned above, and when external force is applied to this type of resin, the coating structure is destroyed and a softening phenomenon occurs, and when the external force is removed, it takes a long time. The tree mentioned above has the property of recovering to its original state over time. As mentioned above, the pressing force of fat △ is approximately 1, which is slightly higher than the initial pressing force that imparts fluidity, compared to the pressing force < 150.6 k (1/cm2 or less) during running in the pipe after flowing.
．． Set the pressure to about 5 kg/cm2. In the case of such a pressure setting, the initial pressing force is Lande 1
--It acts on the inside of the pipe in the section 2, has almost no effect on the inside of the existing pipe, and also has no effect on the inside of the existing pipe.

[The pressing force is approximately 0.6 kg/cm, so as to maintain a slight pressure difference with respect to atmospheric pressure.
By setting the pressure to a low pressure of less than cm2, it is possible to reliably avoid the phenomenon of blowing from corroded holes even in the aged existing piping 1. In addition, when the resin filler flows in the pipe due to the above pressing force and the formation of the lining coating film progresses, and the flow rate of resin A decreases due to the formation of the coating film, the above pressing force is reduced in response to the decrease in the resin group. Then, the amount of air from the compressor 6 is controlled by the air blowing control device 7 so that the flow rate of the lining resin A is constant. That is, as resin (2) decreases, the flow rate of resin A tends to increase accordingly, and this change in flow rate is reflected by the pressure gauge 20. Flow f
Detected by f1fff21. This is because the pressure inside the existing pipe 1 on the front side in the direction of travel of resin A and the discharge of accumulated air from inside the pipe are both relatively changed in relation to changes in the flow rate to the lining resin. Therefore, by detecting this state of change using the pressure gauge 20 and the flow meter 21, a change in the flow rate of the resin A is detected, and this detection signal is sent to the transmitter 22. antenna 2
5 and is received by the antenna 17 of the air blowing control device 7 on the starting end side, and is calculated together with the pressure signal from the pressure gauge 15 to obtain a pressing force that keeps the flow speed of the resin A constant. Relief valve 18. Throttle valve 12. Open/close valve 1
4 is controlled, thereby the airflow of pressurized air introduced from the compressor 6 through the launcher 2 into the existing piping 1 is controlled to tll 611, and the pressing force of the resin A is automatically increased in accordance with the decrease in the amount of resin. Controlled to be attenuated. In this way, the lining resin 1 is filled with a launcher of a predetermined length connected to the injection side pipe end of the existing piping so as to be filled and closed in a liquid state, and an initial pressing force that imparts fluidity to the filled resin is applied. At the same time, the Wt dynamic velocity inside the pipe is controlled to be approximately constant from the starting end of the pipe to the reaching end, and this flow causes the required amount to be applied to the inner surface of the existing pipe over its entire length. A lining coating film of uniform thickness is formed. On the other hand, in the repair work of the present invention, the length of the existing pipe 1 to be repaired is approximately υ1 for the amount of flow of resin A in the pipe due to the pressing force and the quality of coating film formation due to the amount of resin filled in one time. If the length of the repair section is long, the repair section is divided into sections by filling the resin and flowing it multiple times depending on the length.This allows the length of the repair section to be increased and extended as desired. is possible. In addition, in the illustrated embodiment, the resin △ has its rear end surface pressed by pressurized air from the compressor 6, but the flow of the resin A is caused, for example, in the pipe on the front side in the direction of travel of the resin. A pressure difference may be created in the tube by applying a negative suction force, etc., and this pressure difference may be used to apply a pressing force to the rear end surface of the resin A. [Effects of the Invention] As explained above, the lining repair method according to the present invention is achieved by connecting a launcher equipped with a throttle valve that controls the air flow rate of pressurized air to the injection side pipe end of the existing pipe. In addition to increasing the initial pressing force to give fluidity to the resin A introduced into the tube, the initial pressing force that gives fluidity to the resin A introduced into the tube is increased at a part of the launcher, and when moving inside the tube, the pressing force is increased in response to a decrease in the amount of resin (e.g., 0.6 kg/cm' or less). The pressure is attenuated and the lining resin flows using static pressure that keeps the flow velocity constant. During this flow, the resin remains on the inner surface of the tube due to the adhesion force to the wall surface as it flows while contacting the inner surface of the tube. Since this residual resin is used to form a coating film on the inner surface of the tube, the following effects can be obtained. (1) First, according to the present invention, the resin filled from a part of the launcher is given fluidity by a high initial pressing force, and when the resin is flowing, the pressing force applied from the rear end surface of the resin is turned into static pressure. Set the amount of resin that remains on the inner surface of the tube (coating film thickness), and the flow rate of the resin. Since it can be freely controlled by selecting the resin viscosity, etc., the thickness of the lining coating film can be adjusted to the desired thickness.
It can be formed to a film thickness of about 10 mm to 10 mm. (2) In addition, when the resin is made to flow with static pressing force as described above, after the resin has been given fluidity due to its thixotropic property, the resin undergoes a softening phenomenon and the pressing force is small. Since the flow is based on the amount of air, the blower used can be a baby compressor or a small cylinder, and the equipment can be significantly downsized. (3) In addition, it is possible to use a high-viscosity resin that has good thixotropy, which reduces the sagging phenomenon of the lining coating. Therefore, it is possible to eliminate variations in film thickness such as being thinner on the upper surface side and thicker on the lower surface side of the tube, and to form a coating film with a uniform thickness in the circumferential direction of the tube. (4) Furthermore, the air flow sent into the pipe to flow the resin has a low pressure, and because it always flows through the pipe that has been lined with residual resin after the coating has been formed, the inner surface of the pipe has thixotropy. Due to the interposition of the resin coating, the air flow does not come into direct contact with the inner wall surface of the pipe itself, so it is possible to reliably prevent the phenomenon of blowing through corrosion holes that occurs in conventional gas phase methods. . (5) Furthermore, a receiver equipped with a pressure gauge J3 and a flow meter is connected to the outlet side pipe end of the existing pipe to detect the pressure inside the discharge side pipe and the amount of discharged air that changes as the filled resin flows in the pipe. Based on signals detected from the pressure inside the pipe and the amount of discharged air, the blower control device is controlled to maintain a constant flow rate of the lining resin flowing inside the pipe, even if the amount of resin decreases. A lining coating film of uniform thickness is formed.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view schematically showing an example of the repair method according to the present invention, and Figs. 2 and 3 show the relationship between the pressing force during resin flow, the adhesive force influence coefficient, and the resin shear stress according to the present invention. The vector diagram shown, FIGS. 4 and 5 are explanatory diagrams of the shape of the resin end face showing the relationship between the resin pressing force during resin flow according to the present invention, 119J9 and the running speed, and FIGS. 6 and 7 are respectively FIG. 6 is an explanatory diagram showing the component force relationship of pressure at the same point in FIGS. 4 and 5; FIG. DESCRIPTION OF SYMBOLS 1... Existing piping, 2... Launcher-13... Receiver, 4... Resin injector, 5... Opening/closing control valve, 6...
... Compressuna, 7... Air blow control device, 8... Switching solenoid valve, 11... Filter, 12... Throttle valve, 1
3... Flow rate control unit, 14... Opening/closing valve, 15... Pressure gauge, 16... Flow rate controller, 17... Antenna, 18... Relief valve, 20... Pressure gauge, 21・
... Ryutan meter, 23... Transmitter, 25... Antenna,
26...Resin separation hopper, 28...Shutoff valve. A... Lining resin.

Claims (1)

[Scope of Claims] A resin is filled in the pipe at one end of the existing pipe in a liquid state so as to fill and block the inside of the pipe for a required length from the opening thereof, and the filled resin has a diameter of the pipe, a resin viscosity of Based on related conditions such as the length of the filled resin, a required static pressure is applied to the rear end surface of the filled resin so that the filled resin flows in a block shape inside the tube at a set speed necessary to form the required film thickness on the inner surface of the tube. Gives fluidity to the resin group, and when the resin group flows in the pipe, the above-mentioned pressing force is attenuated in accordance with the decrease in the amount of resin due to the formation of a coating film, and the flow rate of the resin group in the pipe is maintained approximately constant. In the case where the flow is controlled as shown in FIG. Then, a receiver equipped with a pressure gauge, a flow meter, etc. for detecting the pressure inside the discharge side pipe and the amount of discharged air, which changes as the filled resin flows in the pipe, is connected to the other outlet side pipe end, A method for repairing lining on the inner surface of a pipe, characterized in that the air blowing control device is controlled to maintain a constant flow rate of the lining resin inside the pipe based on a signal detected by the amount of air.