JP5237779B2 - Lining method for water supply pipe and sliding member used for the lining - Google Patents

Description

  In order to rehabilitate existing piping installed in high-rise buildings such as apartment buildings or office buildings such as condominiums, the present invention cleans the inner surface of the piping and polishes deposits such as rust, scale and dirt. The present invention relates to a lining method for performing secondary coating after primary coating using a solvent-free two-component epoxy resin coating after sweeping off, and a sliding member used for the lining.

  Conventionally, as a rehabilitation method for existing water supply pipes of this type, the conventional technique is to scour the inner surface of the pipe and then apply a multilayer lining by applying two or more coats using a solventless two-component epoxy resin paint. Several inventions are known.

  As a first known example according to these prior arts, 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 is still flowing by blowing air for lining. Because the lining of the next process (secondary process) is performed in the initial to middle stage of dry touch, which has a possibility, the coating film applied in the previous process is still smooth (substantially completely dry). Therefore, the flow frictional resistance is relatively large, and the sliding flow of the paint in the next process is suppressed. In particular, a relatively thick coating film can be formed at the joint portion of the pipe. Since a secondary coating is made when many soluble molecules and / or polar groups remain in the coating film, the coating films formed by the primary coating and the secondary coating are integrated by a crosslinking reaction to form a high-quality coating film. To do . (See Patent Document 1)

  Moreover, as a second known example according to the prior art, the coating section is divided for each branch pipe from one end side to the other end side of the existing pipe, and the length of the entire pipe is divided for each section. In addition, an amount of paint capable of forming a preset film thickness corresponding to the inner diameter is charged all at once, and the paint is blown sequentially from the modified slag flow into an annular flow by an air supply fluid of a predetermined pressure to apply the primary coating. After the film is formed, a predetermined amount of paint that can be applied up to a position exceeding the position of the second joint member in each divided painting section is supplied as a reference, and the paint is supplied to the air supply fluid or the sliding member ( Pigment) is used to form a secondary coating film that can flow at once to maintain the state of the modified slag flow, and the coating thickness is corrected by secondary coating on the thin coating film on the start side. By forming a coating film with a well-balanced thickness as a whole Forming is that it is possible to. (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 2006-232128 A 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 long 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.At that stage, the paint changes from the metamorphic slag flow to the annular flow, and the paint is applied to the pipe wall in the annular flow state. 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, and in the secondary coating, the coating film flows in the same manner as the primary coating. Therefore, there is a problem that the amount of paint distribution on the terminal side is further increased, 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 middle portion is 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 particular, since the inside of the pipe is allowed to flow for an air supply time that is not significantly different from that of the primary coating, there is a problem that an air supply ripple remains on the formed coating film and a uniform coating film cannot be formed.

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 applied with an elastic foam having a diameter larger than the inner diameter of the branch pipe and is performed after the coating of the primary coating is completely dried, variations in coating thickness due to the primary coating are corrected. In addition, the primary coating film has a very small amount of soluble molecules, and has a problem that the adhesion (bonding) of the secondary coating film to the primary coating film is weak and easily peeled off.

  Therefore, thinning of the film thickness in the vicinity of the start end of the pipe to be painted is eliminated, the paint distribution amount is made approximately uniform from the start end to the end, the paint film balance is made substantially uniform, and the paint used is wasted. , Shortening the work time between primary coating and secondary coating, completing the lining on the same day, and correcting the coating thickness variation of the primary coating over the entire surface by the secondary coating. It has a problem to solve.

  As a specific means for solving the above-mentioned problem, the first invention of the present invention is to clean the inside of an existing pipe that is piped in a building and into which a plurality of branch pipes are branched, and then from one end side of the existing pipe. The coating section is divided into the branch pipes branched to the other end side, and solvent-free two-component epoxy resin paint is supplied from the end of the pipe for each coating section, and the primary coating and sliding by blowing are performed. This is a lining method in which a coating with a predetermined thickness is formed on the inner surface of the pipe by performing secondary coating by extending using a moving member. The solvent-free two-part epoxy resin paint used is a pot life at room temperature. Is in the range of 4 to 6 minutes, and the sliding member used in the secondary coating is made of silicon as a material having a spherical surface with a smooth surface, and its diameter is to be painted. In the range of -0.4 to -1mm with respect to the inner diameter of the pipe After forming the primary coating film by blowing in each of the divided sections, supply the required amount of paint and slide before the coating film in each section gels. The secondary coating is applied by the member, and the coating portion that is thinly formed by the primary coating is overcoated by the secondary coating, and the coating portion that is formed thickly is stretched to obtain a uniform coating thickness as a whole. It is a lining method whose main feature is to form.

  In the first invention, the solvent-free two-component epoxy resin paint having a pot life of 4 to 6 minutes has a viscosity in the range of 12000 to 16000 (mPa · s) and has thixotropic characteristics. The Ti value is about 3 to 4 and the time to reach H hardness is 2.5 to 3.5 hours; and the amount of paint applied at the time of primary coating is 10% of the amount calculated for each coating section To supply a larger amount; as an additional requirement.

  The second invention according to the present invention is a sliding member (pig) for applying paint by extending the paint for coating the inner surface of a pipe, which is a silicon material to which the paint is difficult to adhere and having a hardness in the range of 30 ± 5. The water supply is characterized by the fact that it is formed into a spherical shape and the surface is a smooth surface, the diameter of which is a small diameter of about -0.4 to -1 mm with respect to the inner diameter of the pipe to be painted. It is a sliding member used for pipe lining.

  In the water pipe lining method according to the first aspect of the present invention, the solvent-free two-component epoxy resin paint used has a pot life in the range of 4 to 6 minutes at room temperature and is used in the secondary coating. The sliding member is made of silicon as a material and formed into a spherical surface with a smooth surface. The diameter of the sliding member is -0.4 to -1 mm smaller than the inner diameter of the pipe to be painted. After a primary coating film is formed by blowing for each of the divided sections, a required amount of coating material is supplied before the coating film in each section is gelled. The next coating is applied, and the coating part that is thinly formed by the primary coating is applied repeatedly by the secondary coating, and the thick coating part is stretched to form a uniform coating thickness as a whole. By doing so, in the primary painting in each section For the coating film formed unbalanced with the starting side being thin and thick at the terminal side, the thickness of the coating formed thinly on the starting side is corrected by secondary coating, and the surplus coating is not necessary. However, the coating film portion that is thickly formed can be stretched and formed to have a uniform coating film thickness as a whole.

  In addition, since paint with a relatively short pot life is used and secondary coating is performed with a spherical sliding member with a smooth surface that the paint does not adhere to before the primary coating film gels, useless paint It is not necessary, and the coating film of the primary coating with air supply ripples and variations is made uniform with a sliding member whose surface is smooth and slippery, and the coating film surface can be formed smoothly and the work time is also remarkable. There is also an advantage that the lining can be completed on the same day.

  Furthermore, the sliding member used for the lining according to the second invention is formed of a silicon material that is hard to be coated with a paint having a hardness of 30 ± 5 in a spherical shape and a surface having a smooth surface, and its diameter is By forming it to a small diameter of about -0.4 to -1 mm with respect to the inner diameter of the pipe to be painted, it is possible to smoothly form the surface of the paint film that has been stretched without adhesion of the paint, and to deform the sliding member itself Therefore, it is possible to form a substantially uniform coating film on the entire inner surface of the pipe, and it is possible to eliminate waste because no extra paint is required.

  A lining method according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 schematically shows a part of existing pipes such as water supply pipes in an apartment house such as an apartment, and FIG. 2 schematically shows a paint mixing and supplying apparatus used in the lining method. FIG. 3 is an explanatory diagram for explaining the state of primary coating in the implementation of the lining method, and FIG. 4 shows the vicinity of a rising joint (elbow) portion of a branch pipe applied by the primary coating. FIG. 5 is a cross-sectional view schematically showing a state in which a coating film formed by primary coating is extended by secondary coating.

  First, in FIG. 1, an existing pipe 1 to be lining has a plurality of branch pipes 1 a, 1 b, 1 c,... Branched through appropriate joint members, and is connected to the free end side of each branch pipe. Generally, a discharge member such as a faucet is attached via first joint members (elbows) 2a, 2b, 2c,. Further, 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 of the existing pipe 1 is a meter mounting 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. Then, the branch pipe 1b is divided into sections C, D,... In accordance with the section B up to the third joint member 4b at the branch point. Then, the coating is supplied, and lining is performed by primary coating that is blown and spread with air of a predetermined pressure and secondary coating that moves the sliding member and extends the coating.

  The amount of paint to be added is calculated in advance by calculating the pipe diameter and length of each section, and by calculating 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. The two-component epoxy resin paint used is a paint having a relatively fast curing time. As an example, for example, “Epoliner 3000” (registered trademark) (manufactured by Kansai Paint Co., Ltd.) When the pot life as a paint after mixing with the curing agent is normal temperature (environmental temperature 25 ± 3 ° C. range) and the paint temperature is 30 ± 3 ° C., about 4 to 6 minutes, preferably 4 minutes 30 seconds to 5 minutes 30 The viscosity is in the range of 12000 to 16000 (mPa · s) in about seconds, the thixotropic property is about 3 to 4 Ti, and the time to reach H hardness is 2.5 to 3.5 hours. .

In addition, as an extension pig used in secondary coating, that is, as a sliding member, for example, a silicone material that is difficult to attach paint is formed into a bullet body (with a hardness of 30 ± 5) and its surface is slippery. Is formed into a smooth surface, and the diameter of the ball is formed to a small diameter of about -0.4 to -1 mm with respect to the inner diameter of the pipe to be painted. Inside, a 0.2 mm gap is formed around the spherical shape of the sliding member, and in the case of −1 mm, a 0.5 mm gap is formed around the spherical shape.

  In an actual lining, a working tube capable of storing a required amount of paint is previously attached to the open end side of each branch tube 1a, 1b, 1c... A means for supplying gas is connected. Then, a predetermined amount of paint is collectively stored in the work tube, and thereafter, in the primary coating, a paint film is formed by sending or blowing the paint with an air supply fluid, and in the secondary painting, a spherical slide is formed. The moving member is inserted, the sliding member is moved by the air supply fluid from the air supply means, and the paint is stretched to form a uniform coating film to line the entire pipe.

  The paint mixing and feeding apparatus 5 used in the lining method of the present invention is shown schematically in FIG. 2 in terms of the supply principle, and the base 6 and the curing agent of the two-component epoxy resin paint are separated into separate tanks 6. , 7 respectively, and the required amounts are supplied from the tanks 6 and 7 to the mixing means 12 through the supply pipes 8 and 9 and the pumps 10 and 11, respectively, and the paint mixed by the mixing means 12 is applied to each of them. Lining is performed by introducing a pre-calculated amount into a work tube provided at the end of each power section. In this case, the tanks 6 and 7 are provided with stirring means 13 and 14 for stirring the base and the curing agent, and pressure gauges 15 and 16, and an inert gas supply pipe 17 for pressurization, 18 are connected via valves 19 and 20, respectively, and the supply pipes 8 and 9 are provided with valves 21 and 22 between the tanks 6 and 7 and the pumps 10 and 11, respectively. Circulation pipes 23 and 24 for circulating the base and the curing agent in the tanks 6 and 7 by using a part are provided through valves 25 and 26, respectively.

  The mixing unit 12 includes a stirring member 27 that stirs and mixes the base and the curing agent supplied from the supply pipes 8 and 9, a stirring and mixing chamber 28, and a discharge valve 29. The base and the curing agent are supplied from the supply pipes 8 and 9 through the three-way switching valves 30 and 31. In addition, the supply pipes 8 and 9 are provided with temperature sensors 32 and 33, pressure sensors 34 and 35, valves 36 and 37, and the like, and further, the tanks 6 and 7 and the valves 30 and 31 of the mixing means 12 are provided. The route to reach has a double structure as indicated by the phantom line, and pipes 38 and 39 for circulating the heat retaining fluid to maintain a constant temperature (about 30 ° C.) so as not to be affected by the outside air temperature are provided. The cleaning pipes 40 and 41 for cleaning the stirring and mixing chamber 28 are connected to the valves 30 and 31. The stirring and mixing chamber 28 is covered with a cooling means 42 that uses a Bertier element in order to suppress the temperature at which heat is generated by mixing.

  Therefore, for mixing the base of the two-component epoxy resin paint and the curing agent, first, the required amounts of the base and the curing agent are respectively put into the tanks 6 and 7, and communicated with the tanks 6 and 7, respectively. Among the valves of the pipes to be closed, all the valves except for the valves 19 and 20 are closed, the valves 19 and 20 are switched to the atmosphere opening side, the vacuum pump hoses are respectively connected to the atmosphere opening side ports, The air in the tank 7 is decompressed and the air bubbles contained in the base and the curing agent are discharged over about 1 hour. Thereafter, the valves 19 and 20 are switched to the inert gas side, and the tanks 6 and 7 are filled with nitrogen. An inert gas such as a gas is introduced and maintained in a pressurized state.

  Branch pipes 1a and 1b for each section to be painted. Each of 1c... Is pre-connected with a work tube. For example, as shown in FIG. 3, an L-shaped work tube 43 is connected to the first joint member 2b of the branch tube 1b in the section B in advance. The working tube 43 is attached to a reducer 44 screwed to the faucet mounting tube 2b-1 of the first joint member 2b so that it can be easily attached and detached via a male / female cam lock 45. Further, a male cam lock 46 is attached to the other end portion side of the work tube 43 to which an air supply pipe or hose for blowing air supply fluid, that is, air can be easily connected.

  After the preparation is completed, primary coating is performed. In this primary coating, lining is started from section B. In this case, a base and a curing agent in an amount capable of painting the section B calculated in advance are supplied to the mixing means 12 via the supply pipes 8 and 9 and the pumps 10 and 11, and the stirring and mixing chamber is supplied by the stirring member 27. While being mixed at 28, the discharge valve 29 is sequentially opened and taken out, put into a predetermined container, and conveyed (carried) to the coating position in the section B, that is, the position of the branch pipe 1b.

  The paint carried from the cam lock 46 side is put into the work tube 43, and then the air supply pipe or hose is connected to blow the air of the required pressure (air supply fluid), thereby flowing or blowing the paint. The entire branch pipe 1b in the section B extending from the faucet mounting pipe 2b-1 to the third joint member 4b is painted.

  In the initial stage of blowing, the paint flows in a metamorphic slag flow, then changes to an annular flow, and reaches the third joint member 4b at the branch point of the branch pipe 1b while applying the paint to the pipe wall. Application is performed to a position slightly beyond the joint member. During the lining of the section B, the ends of the other branch pipes 1a, 1c, and 1d are in a sealed state, and only the meter mounting end 1f is in an open state. Similarly, the ends of the branch pipes other than the lining section are sealed, and only the meter mounting end 1f is opened.

  Next, the section C is lined. Also in this case, similarly to the above, the work tube 43 is attached to the end of the branch pipe 1c in advance, and paint is supplied from the work tube 43 and blown by air (air supply fluid), and the annular slag flow is changed to the annular flow Then, the coating is applied to the pipe wall while reaching the third joint member 4c at the branch point, and is applied to a position slightly beyond the third joint member.

  Further, the section D is also lined in the same manner as described above. In this way, coating is applied to the branch joints 1b, 1c,... Branched at the intermediate portion from the one end side to the other end side of the existing pipe 1 to the third joint members 4b, 4c,. After that, the section A is lined. That is, the working tube 43 is also connected to the end of the branch pipe 1a in advance, and paint is put into the working tube 43 in a lump, and the paint is supplied to the meter mounting end 1f on the other end side by an air supply fluid. It is blown and the paint wall is painted on the pipe wall by changing from metamorphic slag flow to annular flow. In this case, since the length of the pipe in the section A is relatively long, the calculated amount of the paint is supplied accordingly, and the air supply time for blowing is increased accordingly.

  In any of the sections described above, the paint that is blown by the air-feeding fluid is such that the applied paint flows as a metamorphic slag flow to approximately the middle of each section, and then flows as an annular flow. However, even in an annular flow, the coating flows and flows so as to be pressed against the pipe wall.

  In the primary coating, the blown-up coating with the air-feeding fluid is an amount obtained by increasing the amount of paint introduced in each section by about 5 to 10% of the calculated amount. Painted in an annular flow, but the painted paint (coating film) is inevitably non-uniform in that the start side is thin and the end side is thick in the tube length direction of each coating section, and the ripples remain in some areas. Paint distribution.

  In this case, the uneven coating distribution means that the coating 48 formed by the primary coating has the first joint members 2a, 2b in the branch pipes 1a, 1b, 1c,... As shown in FIG. 2c,... Is thin on the side of the second joint members 3a, 3b, 3c,..., And gradually becomes thicker from around the second joint members 3a, 3b, 3c,. The coating film thickness varies between the start end side and the end end side. The reason is that ripples remain in part due to the air supply fluid and the paint on the start side flows.

  After the primary coating is completed, the secondary coating is performed in the same procedure (order) as the primary coating. That is, secondary coating is sequentially performed from the branch pipe 1b in the section B. In this secondary coating, a required amount of paint is put into the work tube 43 connected to the end of the branch pipe 1b, and then a bullet 47 (pig) sliding member 47 which is slippery and does not adhere to the paint. Then, an air supply pipe or hose is connected to the end of the working tube 43, and the sliding member 47 is pushed out by the air supply fluid of the required pressure to reach the third joint member 4b at the branch point. , Only the sliding member 47 is discharged from the meter mounting end 1f, and the supply of air is stopped immediately when the discharge is confirmed.

  In the secondary coating in the section B, the coating material for secondary coating pushed out by the sliding member 47 from the work tube 43 is stretched with a substantially uniform thickness from the end of the branch tube 1b over the entire inner wall surface. When the second joint member 3b is reached, it is almost lost or may remain a little, but it is almost lost inside the second joint member 3b.

  Still, the sliding member 47 continuously moves beyond the second joint member 3b. In this case, as shown in FIG. 5, in the second joint member 3b and thereafter, the sliding member 47 extends and uniformizes the non-uniform and rippled coating film 48 formed by the primary coating. It moves to the third joint member 4b at the branching point, and is stretched by the sliding member 47 that is slippery and does not adhere to the paint. The coating film 48a becomes uniform, and its surface becomes a smooth surface.

  Further, even if the sliding member 47 reaches the third joint member 4b, which is a branch point of the section B, it does not end, but the sliding member 47 continues to the meter attachment end 1f after the third joint member 4b. It moves, and the coating film 48 that has been primary-coated in the section A is stretched and uniformed to obtain a smooth coating film 48a. The surplus paint is sequentially lost in the subsequent third joint members 4c and 4d.

  Further, in the section C and the section D, similarly to the section B, secondary coating is performed using a required amount of paint and the sliding member 47. Also in this secondary coating, the sliding member 47 smoothly moves to the meter mounting end 1f beyond the third joint members 4c and 4d, and is smoothed by the secondary coating in the previous section B. The sliding member 47 repeatedly passes through the primary coating portion of the section A in part, but quickly passes with less resistance after the second time.

  Finally, the section A is secondarily painted using the required amount of paint and the sliding member 47 in the same manner as described above. In this case, a slightly larger amount of paint than the sections B, C, and D is put in, and the paint is pushed out by the sliding member 47 to enter the first joint member 2a, the branch pipe 1a, and the second joint member 3a. A thick film formed by primary coating is formed between the second joint member 3a and the third joint member 4b, which is a branch point of the section B, after a coating film having a required thickness is formed. The portion of the coating film is stretched and moved to form a smooth coating film 48a having a uniform thickness. After passing through the third joint member 4b, it has already been formed smoothly with a uniform thickness. It passes quickly to the meter mounting end 1f with a small resistance.

  In the case of these secondary coatings, a required amount of coating material is supplied and stretched by the sliding member 47 to form a smooth coating film 48a having a uniform thickness. The coating 48 is made uniform, and the coating supplied in the secondary coating is mainly for overcoating the thinly formed coating on the starting end side to ensure the planned thickness, In this case, it is consumed between the first joint member and the second joint member in each section, and in particular, it is overcoated with a thick overall leaving a space through which the sliding member 47 passes in a wide interior of each joint member. It becomes like this. Accordingly, a relatively thick and stable coating film is formed inside each joint member of the first joint member 2a... To the third joint member 4b.

  As described above, the paint used is a paint with a relatively fast curing time. For example, even if there are five faucet parts in one water supply pipe in an apartment house, The extending time is about 4 to 10 seconds, and the extending by the sliding member 47 is substantially the same time, and the time required for the primary coating and the secondary coating is 10 to 10 hours even if the carrying and loading time of the paint are taken into consideration. Finish within 15 minutes. In particular, since the secondary coating is performed uniformly within the pot life time of the paint supplied in the primary coating or before the formed coating film is gelled, the overcoating and the stretching are performed uniformly. A coating film can be formed. And if about 3 hours pass after completion | finish of a coating operation, since a coating film will reach H hardness, water can be passed on the day.

Further, as described above, the sliding member 47, which is an extension pig used in secondary coating, is formed into a bullet body (having a hardness of about 30) using silicon, which is difficult to attach paint, as a surface thereof. It is formed into a smooth surface with good sliding, and the diameter of the ball is formed to a small diameter of about -0.4 to -1 mm with respect to the inner diameter of the pipe to be painted. For example, the inner diameter of the existing pipe is 18 If it is 0.6 mm, the sliding member 47 having a maximum diameter of 18.2 mm and a minimum of 17.6 mm is used. In particular, in a pipe having an inner diameter of 18.6 mm used in the experiment, a diameter of 18.00 mm is formed so that a space of 0.3 mm is generated between the inner peripheral surface of the pipe and the outer peripheral surface of a sphere (pig). When a sphere was used and the sphere was slid by applying paint, a smooth and uniform coating film having a thickness of 0.3 mm was formed on the inner wall surface of the pipe. Therefore, the size of the sliding member may be selected according to the thickness of the coating film to be formed.

  In the secondary coating using the sliding member 47, in short, the sliding member 47 is moved at a predetermined speed by the low-pressure air supply fluid. Unlike the blowing of the primary coating, the air supply fluid is used in the piping. By increasing the internal pressure, the sliding member moves while pushing the coating film to a uniform thickness, and it is not necessary to blow the air supply fluid so strongly. 10 seconds is sufficient even for the longest section A. When the sliding member 47 with good sliding and little paint is discharged from the meter mounting end 1f, the internal pressure in the pipe decreases, so that the air supply is stopped immediately after detecting that. Yes. Therefore, the air supply fluid that transports the sliding member 47 does not act at all to blow the formed coating film 48a.

  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, from one end side to the other end side of the existing pipe The coating section is divided for each branch pipe branched, and the amount of paint that can form the film thickness set for each section is added in a lump, and each paint is blown by the air supply fluid at a predetermined pressure to perform primary coating. And a secondary coating process in which an amount of paint capable of forming a coating film on one end side of each section is added to each section and stretched by a sliding member to make it uniform. The coating material used has a pot life in the range of 4 to 6 minutes at room temperature, and the sliding member used in the secondary coating is formed into a spherical surface with a smooth surface using silicon as a material. The diameter is the same as the inner diameter of the pipe to be painted. Then, it is formed to have a small diameter in the range of -0.4 to -1 mm, and the coating thickness due to the primary coating varies, and the entire surface is made uniform with the sliding member due to the secondary coating. As a result, not only can the waste of materials be eliminated, but also the construction period can be shortened, and the existing piping is not limited to the water supply pipe, for example, a hot water supply pipe or other pipes installed in a factory, etc. Of course, the lining method of the present invention can also be used in tube rehabilitation.

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. It is the layout of the principal part which showed schematically the paint mixer used in implementation of the lining method. It is a side view which shows one Example of the working tube used for the lining method. 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 formation condition of the coating film in the sliding member by secondary coating roughly.

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 ... 3rd joint member 5 ... Paint mixing supply device 6, 7 ... Tank 8,9 ... Supply pipe 10,11 ... Pump 12 ... Mixing means 13,14 ... Agitation means 15,16 ... Pressure gauge 17,18 ... No Active gas supply pipe 19, 20, 21, 22, 25, 26, 30, 31, 36, 37 ... Valve 23, 24 ... Circulation pipe 27 ... Stirring member 28 ... Stirring mixing chamber 29 ... Discharge valve 32, 33 ... Temperature Sensor 34, 35 ... Pressure sensor 38, 39, 40, 41 ... Pipe 42 ... Cooling means 43 ... Working tube 44 ... Reducer 45, 46 ... Cam lock 47 ... Sliding member 48 ... Primary coating film 48a ... Two Next coating film A, B, C, D ...

Claims (4)

After cleaning the inside of the existing piping that is piped in the building and branching a plurality of branch pipes, the coating section is divided for each branch branch from one end side to the other end side of the existing pipe, Solvent-free two-component epoxy resin paint is supplied from the end of the pipe for each coating section, and primary coating by blowing and secondary coating by spreading using sliding members are performed to give a predetermined thickness on the inner surface of the pipe A lining method for forming a coating film,
The solventless two-component epoxy resin paint used has a pot life in the range of 4 to 6 minutes at room temperature,
The sliding member used in the secondary coating is made of silicon as a material having a spherical surface with a smooth surface, and its diameter is -0.4 to -1 mm with respect to the inner diameter of the pipe to be painted. It is formed in a small diameter in the range of
After forming the coating film of the primary coating by blowing for each divided section, before the coating film of each section is gelled, supply the required amount of paint and perform the secondary coating with the sliding member, It is characterized by the fact that the paint film part that is thinly formed by the primary coating is overcoated by the secondary paint, and the paint film part that is thickly formed is stretched to form a uniform film thickness as a whole. Water pipe lining method. Solvent-free two-part epoxy resin paint with a pot life of 4 to 6 minutes
The viscosity is in the range of 12000 to 16000 (mPa · s), the thixotropic property is about 3 to 4 Ti, and the time to reach H hardness is 2.5 to 3.5 hours. The method for lining a water supply pipe according to claim 1. The lining method for a water supply pipe according to claim 1, wherein the amount of paint applied at the time of primary coating is about 10% larger than the amount calculated for each coating section. It is a sliding member (pig) that paints by extending the paint for painting the inner surface of the pipe,
Its surface is formed on the bullet sphere paint adheres hardly silicon material is formed into a sliding good smooth surface, -0.4 to-1 mm approximately with respect to the inner diameter of the pipe is the diameter of the bullet sphere tries to painting A sliding member used for the lining of a water supply pipe, characterized by having a small diameter.

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