JP2006263601A - Method for lining water supply pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for lining the inside of existing piping by a solventless twin pack type epoxy resin coating material enabling execution on the same day without variation in coating film thicknesses. <P>SOLUTION: Coating film sections are compartmentalized by each of the branch pipes respectively diverged from one end to the other end side of the existing piping 1 and with the position of the second joint member for every section as a reference, the positions from the beginning end side to be coated up slightly beyond the same are determined as adjustment requiring areas Al, B1, C1, D1 and the coating materials of the amounts at which these areas up to the position slightly beyond the same can be coated at required film thicknesses are charged and are pushed to be spread by using a sliding member or are fluidized up to an area where the state of a modified slag flow can be maintained by an air-supply fluid to form coating films of a primary coating in the adjustment requiring areas. Where the coating reaches the state of set to touch, the prescribed amount of the coating material is collectively charged and is successively blown to be spread to an annular flow from the modified slag flow by the air-supply fluid to form the coating film of the secondary coating, and thereby the distribution amount of the coating material from the beginning end side up to the terminal side is nearly evened and the coating films of the thickness well balanced over the entire part are formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In order to rehabilitate existing water supply pipes installed in high-rise buildings such as apartment buildings or office buildings such as apartments, the present invention is to polish the inner surface of the pipes and deposits such as rust, scales and dirt The present invention relates to a method of lining using a solvent-free two-component epoxy resin paint after the scouring removal.

  Conventionally, as a rehabilitation method for this type of existing water supply pipe, there is a method in which the inner surface of the pipe is cleaned, and then a multi-layer lining is performed by applying a solvent-free two-component epoxy resin paint twice or repeatedly with an air supply fluid. It is known as a conventional example.

  As one of the known techniques, the cured and dried state is judged by touching the coating film with a finger after lining in the previous process (primary process), and the cured and dried state still has a possibility of flowing by blowing for lining Because the lining of the next process (secondary process) is performed from the beginning to the middle stage of the remaining dry touch, the coating applied in the previous process has not yet become a smooth surface (substantially completely dry). Therefore, the flow friction resistance is relatively large, and the sliding flow of the paint in the next process is suppressed, and in particular, a relatively thick coating film can be formed at the joint portion of the pipe, and the soluble molecule in the paint can be formed. And / or because secondary coating is made at the stage where many polar groups remain, the coatings formed by the primary coating and the secondary coating are integrated by a cross-linking reaction to form a high-quality coating. is there. (See Patent Document 1)

  Further, as another known technique, a storage chamber in which the paint is stored, first air supply means and second air supply means that communicate with the storage chamber and open to the top, And a connecting means to a processing pipe (existing pipe) provided on the side near the bottom, and the main lining (primary coating) is performed by extruding the paint in the storage chamber by air supply from the first air supply means, Subsequently, by supplying air from the second air supply means and performing the follow-up lining (secondary coating), the coating on the starting end side that occurs when the coating is put in and blown and lining is performed in particular. The defect that the film thickness becomes thin is corrected by the follow-up lining, and the whole is formed into a uniform thickness coating film. (See Patent Document 2)

  Furthermore, lining (primary coating) is performed in the pipe by supplying gas. After the primary coating is cured, the coating is re-introduced, and an elastic foam having a diameter larger than the inner diameter of the branch pipe and having open cells is inserted with a synthetic resin. The second coating) is a method of forming a thick coating film by sliding coating with an elastic foam on the coating film on the back of the elbow, which is a weak point of airflow-type coating. (See Patent Document 3)

JP-A-11-276990 JP-A-8-229488 JP-A-4-187269

However, the invention disclosed in Patent Document 1 performs the lining of the next process from the initial stage to the middle stage of dry touch and further adds heating means so as not to be greatly affected by environmental conditions. Although the time has been greatly shortened and the lining can be performed on the same day, the drying process still requires a considerable amount of time, especially in the winter or cold regions where the environmental conditions deteriorate. There is a problem that the drying time becomes longer and the working efficiency is lowered.
Also, depending on the length of the divided coating section, the air feeding time for lining becomes longer, and the film thickness of the joint part, particularly the film thickness in the vicinity of the start end side (up to the second elbow) becomes thin. Have
In addition, the pipe diameter and length for each section are calculated in advance, the amount of paint that forms a coating film with a predetermined thickness is calculated for that pipe diameter and length, and that quantity of paint is added all at once. The paint is pushed out and blown to almost the middle of the lining section, and at that stage, the paint changes from the metamorphic slag flow to the annular flow. Although a coating film is formed, the coating film formed in the pipe has a relatively large amount of paint distributed on the end side of the section. Therefore, there is a problem that the amount of paint distribution on the terminal side is further increased, and the coating film balance is poor and the paint is wasted.

Further, in the invention disclosed in Patent Document 2, when performing the follow-up lining from the start end side to the vicinity of the substantially intermediate portion on the start end side with a thin coating film thickness, the paint is caused to flow in an annular flow near the start end side. The top of the coating film previously formed from the starting end side to the vicinity of the substantially intermediate portion is made to be overcoated.
However, the amount of paint is a small amount up to approximately the middle part of the secondary coating section, and the flow mode is an annular flow formed almost simultaneously with the air supply, and is substantially in the general arrangement state of the existing piping. In order to allow the air to flow through the pipe over a period of time that is not significantly different from that of the primary coating, in addition to supplying and flowing the coated surface before the gel point, which is the primary coating, the effect of overcoating at the elbow is achieved. It has the problem of not appearing.

Further, in the invention disclosed in Patent Document 3, after the primary coating is cured, the coating is reintroduced, and an elastic foam having a diameter larger than the inner diameter of the branch pipe is inserted. Since it is a method of pressing and secondary coating, secondary coating can only be performed after the primary coating film is completely cured, so it takes a long time for the primary coating film to fully cure, and the lining is applied on the same day. Since it cannot be carried out by construction, not only the work efficiency is remarkably lowered but also the construction cost is increased.
In addition, since the secondary coating is sliding coating with an elastic foam, the adhesion to the primary coating surface is inferior to that of the air flow method by blowing and the primary coating is performed after complete drying. The film has a very small amount of soluble molecules, and has a problem that the topcoat adhesion (bonding property) to the primary coating film is weak and easily peeled off.

  Therefore, the film thickness in the vicinity of the start end side of the pipe to be coated is eliminated, the paint distribution amount is made substantially uniform from the start end part to the end part, and the coating film balance is made substantially uniform. There is a problem to be solved by shortening the working time with the secondary coating and applying the lining on the same day, and improving and integrating the bondability between the primary coating and the secondary coating.

  As a specific means for solving the above-mentioned problem, the present invention supplies a solvent-free two-component epoxy resin paint after cleaning the inside of an existing pipe that is piped in a building and branches a plurality of branch pipes. A lining method in which a coating film having a predetermined thickness is formed on the inner surface of a pipe by blowing with a fluid, and a coating section is divided for each branch pipe from one end side to the other end side of the existing pipe. For each divided section, the area from the start end side to be painted to a position slightly beyond that position is set as a necessary adjustment area based on the position of the second joint member, and set for each divided section. The amount of paint that can be applied with the required film thickness slightly exceeding the adjustment area is charged, and the paint is flowed all the way to the place where the metamorphic slag flow can be maintained by the air supply fluid at the specified pressure. Forming a paint film, When the coating film of the next coating is dry to the touch, a sufficient amount of coating material that can form a preset film thickness corresponding to the length and inner diameter of the tube is added for each section. Is a lining method characterized in that a coating film of secondary coating is formed by successively blowing from a metamorphic slag flow into an annular flow with an air supply fluid of a predetermined pressure.

  In the present invention, the amount of paint applied during primary coating is an amount that can be reached while maintaining the state of the metamorphic slag flow up to 40 to 120% beyond the position of the second joint member in each coating section; In primary coating, the applied paint is stretched by a sliding member to form a coating film in a region requiring adjustment; the paint input amount during secondary coating is increased by 20 to 50% from the set amount; The next coating is to form a coating film by pushing the paints that are put in a batch with a sliding member; and the secondary coating is performed from the initial stage of dry touch to the middle stage of dry touch; Is included as an additional requirement.

The lining method for a water supply pipe according to the present invention is to first form a primary coating film in a necessary adjustment area on the start end side in each section, and maintain the state of the modified slag flow in the coating film formation. In order to stop the air supply by flowing at a stroke with the air supply fluid as much as possible, or to extend by using a sliding member to form a coating film in the adjustment area, the coating film on the start side as the adjustment area The coating can be formed in a short time and the coating time of the primary coating can be reduced in a short time. The primary paint formed earlier and the secondary paint film formed later are formed by blowing from the metamorphic slag flow to the annular flow sequentially with the air supply fluid to form the secondary paint film. And paint from the start side to the end side The volume of distribution substantially uniform, there is an advantage that it is possible to form a coating film of well-balanced thickness as a whole.
In addition, since the primary coating is applied to the vicinity of the middle part of each section, it can be completed in a short time, and even if the touch drying time until the secondary coating is long (about 2 hours), the primary coating and the secondary coating are completed. The coating can be applied on the same day, and a secondary coating film is formed on the dry-touched primary coating film on the start side, and a cross-linking reaction is quickly performed between the molecules of both coating films. Thus, there is an advantage that the coating film is integrally bonded.

In the lining method according to the present invention, after the inside of an existing pipe that is piped in a building and a plurality of branch pipes are branched, a solvent-free two-component epoxy resin paint is blown out with an air-feeding fluid. In the lining method of forming a coating film with a predetermined thickness on the surface, when one of the existing pipes is applied by sequentially blowing the paint from the modified slag flow to the annular flow, the one end side and the other There is inevitably a variation (unbalance) in the thickness of the coating film on the end side.
For the purpose of eliminating the variation of the coating film, the coating section is divided for each branched branch pipe from one end side to the other end side of the existing pipe, and the position of the second joint member is determined for each divided section. The amount that can be applied with the required film thickness slightly exceeding the required adjustment area set for each divided section is set as the adjustment area from the start side to be painted to the position slightly beyond that position as a reference. A step of forming a primary coating film in a region requiring adjustment, and a step of causing the coating material to flow to a place where the state of the modified slag flow can be maintained by an air supply fluid having a predetermined pressure. When the film is dry to the touch, a quantity of paint capable of forming a preset film thickness corresponding to the length and inner diameter of the tube is batch-fitted for each section. Blowing sequentially from metamorphic slag flow to annular flow with air supply The process of forming the coating film of the secondary coating, and for the coating thickness variation that was inevitably generated on the starting end side by painting by spreading the paint, In order to adjust the variation, the primary coating is performed only on the start end side, and then the secondary coating is performed over the entire length of each section.

  The lining method of the present invention will be described based on the illustrated embodiment. FIG. 1 schematically shows a part of existing pipes such as water supply pipes in an apartment house such as a condominium, and the existing pipe 1 to be lining is connected with an appropriate joint member. A plurality of branch pipes 1a, 1b, 1c,... Are branched and connected, and a free end of each branch pipe is generally a faucet through first joint members (elbows) 2a, 2b, 2c,. Etc. are attached. In addition, second joint members (elbows) 3a, 3b, 3c,... Are provided at the rising portions of the branch pipes 1a, 1b, 1c,. Are connected via third joint members (cheese) 4b, 4c,..., And the base end side is a meter attachment end 1f. When the branched branch pipe is bent a plurality of times, it is natural that the fourth to fifth elbows are interposed in the bent portion in the middle.

  In the case where lining is performed for regeneration in such an existing pipe 1, the first joint members 2a, 2b, 2c,... The entire interior of the existing pipe 1 including the third joint members 4b, 4c,... And the branch pipes 1a, 1b, 1c,. Lining is performed after the inside is dried and cleaned.

  As one method of lining, in the existing pipe 1 in a state where the inside is cleaned, the base end side (the other end side) of the meter attachment end 1f to which the meter is attached from the end side (referred to as one end side) of the branch pipe 1a Lined up to that). In this case, the lining is performed in a state of being divided for each branch pipe. For example, in the case of the branch pipe 1a on the distal end side, the section A extends to the meter attachment end 1f on the proximal end side. The branch pipe 1b is divided into sections B, C, D,... In accordance with the section B up to the third joint member 4b at the branch point, and lining is performed for each section.

  For the paint used for lining, calculate the pipe diameter and length, etc. for each section in advance, and calculate the amount of paint that forms a coating film with a predetermined thickness at that pipe diameter and length. The amount of paint that is increased by the required amount is added to the amount that has been added. As an example of the paint used, for example, 300 cc / pot life is about 15 to 40 minutes at an environmental temperature of 20 ° C., the viscosity at flow is about 3000 to 15000 cps, and the thixotropic property is Ti value 4.5. The following solvent-free two-component epoxy resin paint (aliphatic curing agent) is a well-known paint.

In actual lining, primary coating and secondary coating are performed for each section so as to form a coating film having a substantially uniform thickness from one end to the other end. For this purpose, a working tube capable of storing a required amount of paint is attached in advance to the open end side of each branch tube 1a, 1b, 1c,..., And a predetermined gas is supplied to the working tube. Means are connected. Further, with respect to the positions of the second joint members 3a, 3b, 3c,... Of the branch pipes 1a, 1b, 1c,. position until setting the main control area a ₁ ~D _{1 ......} respectively, the required amount of coating material branch pipes 1a of the respective main control area a ₁ ~D _{1 ......} which is set in each section by painting each .., 1b, 1c,... Are put together and flowed by an air supply fluid, or are stretched using a sliding member to perform primary coating. The sliding member used in this case is a spherical pig made of an elastic body having a smaller diameter than the pipe inner diameter of the existing pipe 1.

The lining for the primary coating may be from the section A, but it is preferable to start the lining from the section B first when considering the secondary coating process. In the primary coating of this Section B, the required amount of coating material by coating a range of essential adjustment region B ₁ and mass loading, set the sliding member in the rear of the paint, air and sliding member fluid The paint is extended by pressing and moving, or the paint is made to flow as a modified slag flow with the required air supply fluid, and when the modified slag flow collapses, air supply is stopped to form a coating film The primary coating ends. The sliding member that has finished extending the paint pops out from the meter attachment end 1f on the base end side.

Next, the adjustment areas C ₁ and D ₁ in the section C and the section D are applied in the same manner as the section B, that is, the amount of paint for coating the respective adjustment areas C ₁ and D ₁ is applied all at _once. In the same manner as described above, the paint is extended by using a sliding member, or the primary coating is performed by flowing in the state of a modified slag flow with an air supply fluid, and the respective air supply times in these sections BD Is only about 2 to 3 seconds, and the primary coating can be performed in a relatively short time.

Then, the primary coating for main control area A ₁ in the last section A. For branch pipe 1a in the main control area A _1, the length from the second joint member 3a to the fourth joint member 4b is a branch point of the branch pipe 1b is long, preferably, the second joint member 3a Beyond that, that is, the amount that can be painted by being stretched to a position exceeding 120% of the length from the start side to the second joint member 3a or more, or the amount that can maintain the metamorphic slag flow It is better to add paint. And the length of coating becomes longer and the amount of paint increases, so the air feeding time also becomes slightly longer (5 to 7 sec).

  In the case of these primary coatings, there are some parts that need to be adjusted by adjusting the air pressure, air flow, etc., taking into account the piping installation conditions, but the applied paint is slid almost uniformly as a whole. When the sliding member is pushed out by the moving member or is made to flow at once in the state of the metamorphic slag flow by the air feeding fluid and the sliding member jumps out of the meter mounting end 1f, or when the metamorphic slag flow is substantially collapsed To stop.

  That is, as shown in FIG. 2, the paint of the primary coating is pushed by the sliding member or flows while being maintained in the transformed slag flow by the air supply fluid, and the second joint in each section The coating is applied up to a position exceeding the members 3a, 3b, 3c,..., And the coating film 5 of the primary coating is formed substantially uniformly as a whole, or the start side in the flow direction is thick and the end side is thin. In other words, when the sliding member is used, it is substantially equal, and in the case of the modified slag flow, it is pushed by the air supply fluid and flows, so that the leading end side (terminal end side) of the flowing paint gradually becomes Since the amount of the material is reduced, the tip side where the paint flows inevitably is thin and the base end side (starting end side) is thickly distributed. In order to maintain this distribution, the feed is sent when the metamorphic slag flow collapses. It stops you. If the air supply fluid continues to be supplied after the metamorphic slag flow collapses and the air supply time is increased, the paint on the base end side will flow to the tip end side in sequence as an annular flow, contrary to the above. Because it becomes.

  The air supply time for extending by the sliding member or the air supply time until the metamorphic slag flow collapses is generally within 2 to 7 seconds, depending on the installation situation of the pipe. The collapsed state can be detected when the air supply resistance is reduced by jumping out from the attachment end 1f or by the collapse of the metamorphic slag flow. In addition, the air supply is stopped by selectively continuing the air supply within a range of 3 to 20 seconds (partially in the initial state of the annular flow) after the metamorphic slag flow collapses, depending on the installation status of the piping, etc. Also good.

  In any case, the primary coating in each section is not the entire section, but the primary coating film 5 having a predetermined thickness on the start end side in each section is sequentially formed. After completion of the primary coating, if necessary depending on the environment or the like, the air supply fluid heated and maintained at a predetermined temperature by an appropriate heating means with the meter mounting end 1f on the other end opened is supplied to each branch pipe 1a. The primary coating film 5 may be heat-cured by introducing it from the ends of 1b, 1c,. In other words, by heating the paint, the hardening reaction of the paint (formation speed of chain molecular structure) is accelerated, the time to reach the gel point on the coating surface can be shortened, and the crosslinking reaction that proceeds after the gel point Therefore, the curing time of the coating film can be further shortened. The air supply in this case is not the spreading of the paint, so the air is adjusted to an air volume / wind force that does not flow the paint.

  When the coating film 5 of the primary coating is in a dry-to-touch state, that is, in a state where it is cured to the extent that it does not flow, secondary coating is performed. The touch drying in this case is to determine the cured and dried state by touching the end of an arbitrary branch pipe. In the middle of the touch-drying state where it is attached to the finger when pressed moderately with moderate elasticity remaining, and in the late-touch-drying state where it does not adhere to the finger when pressed with a finger and is not semi-cured and does not flow with blasting for lining. There is.

  The secondary coating is performed when the coating film 5 of the primary coating has changed from the initial touch drying to the middle touch drying. Even in this case, the lining is performed from the section B, and a third joint member at the branch point is formed by charging a sufficient amount of paint for coating the section B from the end of the branch pipe 1b and blowing it with an air supply fluid. Bring to 4b.

  In the initial stage of the blowing, the coating 5 of the primary coating exists on the start side, so that the coating flows on the coating, and the coating flows to near the middle of the section by the metamorphic slag flow. It changes to an annular flow and flows along the pipe wall to reach the third joint member 4b at the branching point, and the paint is applied to a position slightly beyond the third joint member 4b. In this case, the secondary coating is blown and spread most of the paint as an annular flow by the air supply fluid, so that the second coating is thinly applied to the start end side of the section B and thickly applied to the end end side, that is, the third joint member 4b side. Although the paint distribution is balanced, the paint distribution is balanced over the entire section B due to the presence of the primary coating film.

  Next, the section C is lined in the same manner as described above. In this case as well, a required amount of paint is introduced from the end of the branch pipe 1c and blown out by the air-feeding fluid in the same manner as described above. Is changed from a metamorphic slag flow to an annular flow, is caused to flow along the pipe wall, reaches the third joint member 4c at the branch point, and is applied to a position slightly beyond the third joint member 4c. Further, in the same manner as described above, the section D is also lined by causing the coating material to flow to a position exceeding the third joint member 4d.

  As described above, the branch pipes 1b, 1c, 1d,... Branched at the intermediate part from the one end side to the other end side of the existing pipe 1 are lined up to the respective branch points of the sections B to D divided in advance. Later, the section A is finally lined. In this case, the coating material is charged all at once from the branch pipe 1a, and the coating material is blown and applied to the meter mounting end portion 1f on the other end side by an air supply fluid. Lining in an annular flow.

  In any of the sections described above, the paint is blown out by the air-feeding fluid, and the paint that has been put in a batch flows to the middle of each section as a metamorphic slag flow, and then flows as an annular flow. Both flow and annular flow can be applied by flowing to press against the pipe wall.

  In the secondary coating, the blown-up coating with the air-feeding fluid is an amount obtained by subtracting the amount of paint applied in each section from the amount calculated by subtracting the amount input by the primary coating from about 20 to 40%. It is applied in a circular flow from the metamorphic slag flow by blowing, but the applied paint (coating film) is inevitably uneven in the pipe length direction of each coating section, where the starting end side is inevitably thin and the terminal end side is thick. It becomes the paint film 6 of paint distribution.

  However, the coating film 6 with non-uniform paint distribution by the secondary coating is totally canceled by the coating film 5 formed by the primary coating, and as shown in FIG. 1b, 1c,..., The second joint member 3a, 3b, 3c,... Is thin on the start side and gradually thicker from slightly beyond the second joint member. The coating distribution (coating film thickness) varies, and the coating film 5 that has been formed earlier is eliminated and a coating film with less variation is formed as a whole. It becomes. Furthermore, you may finish-shape a coating film using the sliding member used by the said primary coating after secondary coating.

Next, the lining method according to the second embodiment of the present invention will be described. Also in the second embodiment, the sections A to D and the adjustment areas A _{1 to} D ₁ are set, and the primary coating is performed in the same manner for each of the adjustment areas as in the first embodiment. Only the secondary coating is applied in a different way.

  That is, until the touch drying after the completion of the primary coating, the same process as in Example 1 is performed, and the secondary coating is performed when the coating film of the primary coating changes from the initial touch drying to the middle touch drying. Do it. In this secondary coating, the sliding member used in the first embodiment, that is, a spherical sliding member (pig) made of an elastic body having a diameter smaller than the inner diameter of the existing pipe 1 is used.

  In this case, a position approximately 20% ahead of the positions of the third joint members 4b, 4c, 4d,... Of the branch pipes 1b, 1c, 1d,. In the same way as the primary coating, the required amount of paint reaching up to 1 is put all at once into the work tube, a sliding member is set behind it, and the sliding member is pressed and moved by the air supply fluid to perform secondary coating. Do. In the section A, since the distance from the one end side to the other end side is long, a larger amount (for example, 40% increase) of paint is added to the section A, and coating is performed by batch charging.

  In the case of this secondary coating, it is performed from the section B. In this section B, the amount of paint used in the primary coating is subtracted and a sufficient amount of paint is applied to the work tube at the end of the branch pipe 1b, and a sliding member is set behind it. The meter mounting end 1f on the other end side is opened, and air supply fluid is supplied to the back of the sliding member, whereby the sliding member is advanced and the paint is extended to at least the third branch point. After reaching the position of the joint member 4b and slightly exceeding the position, the paint is removed, so that the sliding member is discharged to the outside from the meter mounting end 1f on the other end side.

  Next, the section C is lined. In this case as well, as in the lining of the section B, after subtracting the amount of paint used in the primary coating of this section, a sufficient amount of paint is applied to the end of the branch pipe 1c to coat the whole. By setting the sliding member behind and supplying the air supply fluid behind the sliding member, the paint is extended to reach at least the position of the third joint member 4c at the branch point, and the position is slightly changed. The coating is applied up to the point beyond which the sliding member is discharged from the meter mounting end 1f. Similarly, the section D is also lined.

  Finally, the section A is lined. In this case, since there is a distance from one end to the other end and the length of the pipe is longer than that of the branch pipe, a sufficient amount of paint is applied to the end of the branch pipe 1a to coat the whole, A sliding member is set on the surface of the sliding member and air supply fluid is supplied to the back of the sliding member to extend the paint to reach the position of the meter mounting end 1f on the other end side. By discharging the sliding member to the outside, it is possible to paint with a substantially uniform film thickness up to the end.

  In this secondary coating, the paint is pushed from the back side by the sliding member, so that it flows as a whole in the form of a plug flow, and since the outer diameter of the sliding member is determined, it is formed on the starting end side in the primary coating. The secondary coating film 6 is formed so as to be overlaid on the applied coating film 5, and the secondary coating film is gradually and repeatedly applied as the primary coating film 5 becomes gradually thinner. In a region where the primary coating film 5 is not present, coating with a coating film thickness based on the outer diameter of the sliding member can be performed.

  Also in this case, the entire coating film having a film thickness corresponding to the gap between the inner diameter of the pipe and the outer diameter of the sliding member is at least beyond the third joint members 4b to 4d. In each section, a substantially uniform coating film is formed by the coating film 5 by the primary coating and the coating film 6 by the secondary coating. Since the amount of paint is reduced and the resistance is reduced after the third joint members 4b to 4d... Are moved, the movement of the sliding member is accelerated, and when the paint is removed before the sliding member. It becomes even faster and is discharged from the meter mounting end 1f to the outside at once, and the supply of the air supply fluid is stopped at that time.

  In secondary coating using this sliding member, in short, the sliding member is moved at a low speed by the low-pressure air supply fluid, and the sliding member prevents the metamorphic slag flow from being easily removed by the air supply fluid. However, it is effective in that the distance of the uniform thickness of the coating film can be obtained. Since the air supply fluid is air supply at a low pressure, the air supply time is the time until the sliding member is discharged from the meter mounting end 1f to the outside, depending on the length of the pipe (section). In general, it is within 5 to 20 seconds. In addition, in this air supply, because the sliding member is moved, the formed coating film is shaped, but there is almost no action of blowing the paint, and the whole maintains a substantially uniform thickness. Then it becomes hardened.

  In any of the above-described embodiments, the coating film 6 formed by the secondary coating is formed when the coating film 5 formed by the primary coating formed on the start side of each section is in a dry-to-touch state. Since the coating film 5 is formed in a required range on the start end side, for example, if warm air is supplied to accelerate hardening on the start end side, gelation is accelerated, and the touch drying is substantially in the middle stage. The time is also shortened and the start time of the secondary coating is shortened.

  In Example 2, the phenomenon that the primary coating film flows due to the use of the sliding member even when the secondary coating is started when the primary coating film is in the initial dry-to-touch state. Is not seen. This is not due to the secondary coating being blown out, but the paint is stretched by the sliding member, and the portion where the primary coating is present is overcoated, and the primary coating is not present. This is because a coating film having a required thickness is formed for the portion.

  Therefore, the coating process is completed in a relatively short time (within 2 hours) depending on the season and environment (outside air temperature) when performing the secondary coating from the primary coating. It can be done. In addition, the cross-linking reaction is promoted between molecules of the primary coating film and the secondary coating film, resulting in an integrated coating film.

  This is a lining method in which a non-solvent type two-component epoxy resin paint is applied to the inside of an existing pipe such as a water supply pipe that is piped in a building, and the paint is applied from one end to the other end of the existing pipe. In order to eliminate the unevenness (unbalance) in the thickness of the coating film that is inevitably generated between the one end and the other end, when the coating is blown sequentially from the metamorphic slag flow to the annular flow In addition, the coating section is divided for each branched branch pipe from one end side to the other end side of the existing piping, and the starting end to be painted on the basis of the position of the second joint member for each divided section From the side to the position slightly beyond that position is set as the adjustment required area, and the adjustment required area is a limited short area on the start end side where the coating film is likely to be thinly formed. Blowing in a range that can maintain the state of slag flow By forming the coating film first (by primary coating) in a short process, it is possible not only to secure a coating film of the required thickness, but also to take time to dry the touch for secondary coating In addition, the coating film formed by blowing from the modified slag flow to the annular flow in the secondary coating is formed thin on the start side and thick on the end side. It is possible to form a coating film having a substantially uniform film thickness on the entire inner surface of the existing pipe by forming the coating film of the next coating, and the existing pipe is not limited to a water supply pipe, for example, a hot water pipe Or, as a matter of course, the lining method of the present invention can also be used in pipe rehabilitation such as other pipes disposed in factories or the like.

It is explanatory drawing which showed schematically the condition of the water pipe in the apartment house which can apply the lining method of the Example which concerns on this invention. In implementation of the lining method, it is sectional drawing of the principal part which showed schematically the condition of the coating film of the one end part side (start end part side) primary-coated. In implementation of the lining method, it is sectional drawing of the principal part which expanded and showed the situation of the coating film of the one end part side (starting end part side) secondary-coated schematically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Existing piping 1a, 1b, 1c, 1d ... Branch pipe 1f Meter attachment edge part 2a, 2b, 2c, 2d ... 1st coupling member 3a, 3b, 3c, 3d ... 2nd coupling member 4b, 4c, 4d ... 1st 3 joint members 5 Primary coating film 6 Secondary coating film A, B, C, D Temporarily divided sections A ₁ , B ₁ , C ₁ , D ₁ adjustment area

Claims (6)

After cleaning the inside of an existing pipe that is piped in a building and branching a plurality of branch pipes, a solvent-free two-component epoxy resin paint is blown off with an air supply fluid to coat the inner surface of the pipe with a predetermined thickness A lining method for forming
A coating section is divided for each branch pipe branched from one end side to the other end side of the existing pipe, and the start end side to be painted on the basis of the position of the second joint member for each divided section To a position slightly beyond that position as the adjustment required area,
The amount of paint that can be applied with the required film thickness, slightly exceeding the required adjustment area set for each section,
The paint is made to flow at once to a place where the state of the metamorphic slag flow can be maintained by an air supply fluid of a predetermined pressure to form a coating film of the primary coating in the adjustment required area,
When the coating film of the primary coating is in a dry-to-touch state, a quantity of paint capable of forming a preset film thickness corresponding to the length and inner diameter of each pipe is collectively charged for each section,
A lining method for a water supply pipe, characterized in that a coating film of a secondary coating is formed by blowing the paint from an altered slag flow to an annular flow sequentially with an air supply fluid of a predetermined pressure. The amount of paint input at the time of primary coating is an amount that can be reached while maintaining the state of the metamorphic slag flow up to 40 to 120% beyond the position of the second joint member in each coating section. The water pipe lining method described. The method for lining a water supply pipe according to claim 1, wherein in the primary coating, the applied paint is stretched by a sliding member to form a coating film in a region requiring adjustment. The method for lining a water supply pipe according to claim 1, wherein the amount of paint applied at the time of secondary coating is increased by 20 to 50% from a set amount. 5. The water pipe lining method according to claim 1, wherein the secondary coating is a method of forming a coating film by extending a batch of paints applied by a sliding member. The method of lining a water supply pipe according to any one of claims 1 to 5, wherein the secondary coating is performed in a state in which the coating film of the primary coating is in the state from the initial dry touch to the intermediate dry touch.

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