A method for improving the sealing performance of flexible connections in concrete sewage pipes

Abstract

This invention discloses a method for improving the sealing performance of flexible connections in concrete sewage pipes. The concrete sewage pipe includes a pipe body, a spigot, a connecting sleeve, and an elastic sealing ring. The spigot is located at both ends of the pipe body. The connecting sleeve is sealed and installed on the spigot at the front end of the pipe body, and the elastic sealing ring is installed on the spigot at the rear end of the pipe body. This method is applicable to newly laid sewage pipes and the renovation of existing sewage pipes. Polyurea filler is pumped into an annular space through a grouting port. After the polyurea filler fills the annular space and overflows from the vent, it blocks the grouting port and the vent. The spigot is heated, and after the polyurea filler cures, a sealing strip is formed between the spigot and the connecting sleeve. This invention proposes a method to improve the sealing performance and sealing stability of flexible connections in concrete sewage pipes.

Description

Technical Field

[0001] This invention relates to the field of sewage pipe sealing technology, and in particular to a method for improving the sealing performance of flexible connections in concrete sewage pipes. Background Technology

[0002] Currently, underground concrete sewage pipes are often laid using trenchless pipe jacking construction methods. Existing sewage pipes, such as... Figure 10 As shown, the sewage pipe 200 has inlets 300 at both ends. The inlet at the front end of the sewage pipe is pre-sealed with a connecting sleeve 400 at the factory, and the inlet at the rear end of the sewage pipe 200 is fitted with an elastic sealing ring 500. During pipe jacking, the rear sewage pipe moves forward, and its front connecting sleeve fits onto the inlet of the front sewage pipe. Figure 11 After the socket connection is completed, the sewage pipe on the front side is pushed forward. During this process, the elastic sealing ring is squeezed and deformed by the connecting sleeve. The deformation capacity of the elastic sealing ring allows the two adjacent sewage pipes to rotate slightly relative to each other, achieving the purpose of flexible connection and maintaining the seal between the connecting sleeve and the socket.

[0003] In practical applications, the elastic sealing ring is subjected to continuous compression and temperature changes. At the same time, organic matter and chemicals in sewage can corrode the elastic sealing ring, causing the sealing effect of the elastic sealing ring to weaken quickly, which in turn leads to sewage leakage and environmental pollution. Summary of the Invention

[0004] In order to address the shortcomings of existing elastic sealing rings at the ends of sewage pipes, this invention proposes a method to improve the sealing performance and stability of flexible connections in concrete sewage pipes.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for improving the sealing performance of flexible connections in concrete sewage pipes, wherein the concrete sewage pipe includes a pipe body, a spigot, a connecting sleeve, and an elastic sealing ring. The spigot is located at both ends of the pipe body, the connecting sleeve is sealed and installed on the spigot at the front end of the pipe body, and the elastic sealing ring is installed on the spigot at the rear end of the pipe body. The above methods are applicable to both newly laid sewage pipes and the renovation of existing sewage pipes; When used for laying new sewage pipes, a leak-stopping sealing ring is pre-installed on the front side of the elastic sealing ring at the rear end of the concrete sewage pipe spigot. An air vent and a grouting port are pre-set at the spigot or connecting sleeve at the rear end of the concrete sewage pipe. When the above method is implemented, two adjacent concrete sewage pipes are connected by a connecting sleeve before entering the soil. An annular space is formed between the connecting sleeve, spigot, elastic sealing ring and leak-stopping sealing ring. When modifying existing sewage pipes, two concrete sewage pipes are connected in the soil by a connecting sleeve. An annular space is formed between the connecting sleeve, the spigot, the elastic sealing ring and the soil. When the above method is performed, a hole is drilled at the spigot of the rear end of the concrete sewage pipe to form an air vent and a grouting port. Polyurea filler is pumped into the annular space through the grouting port. After the polyurea filler fills the annular space and overflows from the vent, it blocks the grouting port and the vent. The insertion port is heated, and after the polyurea filler solidifies, it forms a sealing strip between the insertion port and the connecting sleeve.

[0006] Furthermore, for concrete sewage pipes with a nominal diameter of D, when D <= 600 mm, there is one grouting port, located near the bottom of the spigot; when D > 600 mm, there are at least two grouting ports, one of which is located near the bottom of the spigot; the vent is located near the top of the spigot.

[0007] Furthermore, when the above method is used for laying new sewage pipes, when D<=1200mm, the grouting port and the venting port are set on the connecting sleeve, and when D>1200mm, the grouting port and the venting port are set on the socket.

[0008] Furthermore, the grouting port diameter is d, 20mm. <d<50mm。

[0009] Furthermore, a manual grouting pump or an electric grouting device is used to pump the polyurea filler, with a grouting pressure of P, where 0.2MPa <= P <= 0.5MPa.

[0010] Furthermore, when the above method is used for the renovation of existing sewage pipelines, the temperature of the polyurea packing is T, 10℃, during pumping. <T<20℃。

[0011] Furthermore, when heating the socket, the temperature of the socket is increased at a rate of 2~3℃ / minute. After each 5℃ increase, the temperature rise is paused for 10 minutes. When the socket temperature reaches 40℃, the temperature is maintained for 1-2 hours before the heating equipment is turned off.

[0012] Through the above improvements, the method for improving sealing performance proposed in this invention has the following beneficial effects: 1. In this invention, the sealing performance is improved by injecting polyurea material, which is suitable for both newly laid sewage pipes and the renovation of existing sewage pipes, and has a wide range of applications; 2. In this invention, the polyurea material, after curing, exhibits good adhesion and sealing performance to the connecting sleeve and the socket; 3. In this invention, the polyurea material has low stress after curing, is not subject to compressive stress, and has a slow rate of elastic modulus decay, thus maintaining good elasticity. When making flexible connections between concrete sewage pipes, it can adapt to elastic deformation and ensure the connection is sealed. 4. In this invention, the low-temperature injection of polyurea filler can reduce the permeation of polyurea filler into the soil and improve the injection quality of polyurea filler; 5. In this invention, after the polyurea filler is injected, the curing speed of the polyurea filler is increased by heating the insertion port, thereby improving construction efficiency. Attached Figure Description

[0013] Figure 1 A schematic diagram of the concrete sewage pipe before connection to the pre-set vent and grouting port when laying new sewage pipes.

[0014] Figure 2 for Figure 1 A schematic diagram showing the ring-shaped space formed by the connection of two concrete sewage pipes.

[0015] Figure 3 for Figure 2 A schematic diagram of injecting polyurea filler into the annular space.

[0016] Figure 4 for Figure 3 A schematic diagram showing the sealing of the grouting port and venting port after the medium-polyurea filler has been injected.

[0017] Figure 5 A schematic diagram of the concrete sewage pipe before connection to the pre-set vent port and grouting port of the connecting sleeve when laying new sewage pipes.

[0018] Figure 6 for Figure 5 A schematic diagram showing the ring-shaped space formed by the connection of two concrete sewage pipes.

[0019] Figure 7 To Figure 6 A schematic diagram showing the sealing of the grouting port and venting port after the annular space is filled with polyurea filler.

[0020] Figure 8 A schematic diagram showing the drilling of holes at the spigot of an existing concrete sewage pipe to form a grouting port and an air vent.

[0021] Figure 9 To Figure 8 A schematic diagram showing the sealing of the grouting port and venting port after the annular space is filled with polyurea filler.

[0022] Figure 10 This is a schematic diagram of the existing sewage pipes before connection.

[0023] Figure 11 This is a schematic diagram showing the connection of existing sewage pipes. Detailed Implementation

[0024] The technical solution of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0025] like Figures 1 to 9 This invention proposes a method to improve the sealing performance of flexible connections in concrete sewage pipes, which is used to improve the sealing reliability, sealing effectiveness and lifespan of the connections between underground concrete sewage pipes 3. Figure 1 The front and rear directions of the concrete sewage pipe 3 are defined in order to describe the technical solution. The existing concrete sewage pipe 3 includes a pipe body 4, a spigot 5, a connecting sleeve 6, and an elastic sealing ring 7. The spigot 5 is integrally formed at both ends of the pipe body 4. The outer diameter of the spigot 5 is smaller than the outer diameter of the pipe body 4 so that it can be inserted into the connecting sleeve 6 to form a socket connection structure. The connecting sleeve 6 is pre-sealed and installed on the spigot 5 at the front end of the pipe body 4 in the factory. The elastic sealing ring 7 is made of rubber and has good elastic deformation performance. It is installed on the spigot 5 at the rear end of the pipe body 4. The above method is an improvement on the existing concrete sewage pipes and is applicable to both newly laid sewage pipes and the renovation of existing sewage pipes, thus having wide applicability. Specifically, when used for laying new sewage pipes, based on the aforementioned concrete sewage pipe 3, the factory pre-installs a leak-stopping sealing ring 14 on the front side of the elastic sealing ring at the rear end of the concrete sewage pipe 3. An air vent 8 and a grouting port 9 are pre-set at the rear end of the concrete sewage pipe 3, either at the spigot 5 or the connecting sleeve. The concrete sewage pipe 3 is laid in the soil using a trenchless pipe jacking construction method. When the above method is implemented, before the two adjacent concrete sewage pipes enter the soil, if... Figure 2 and Figure 6 After the rear concrete sewage pipe is pushed forward, it is connected to the socket at the rear end of the front concrete sewage pipe via a connecting sleeve at the front end. Figure 2 This diagram illustrates the socket connection of a concrete sewage pipe with the grouting port and vent pre-installed on the spigot. Figure 6 This diagram illustrates the socket connection of a concrete sewage pipe with the grouting port and vent pre-installed on the connecting sleeve. In this connection, the elastic sealing ring and the leak-stopping sealing ring are pressed between the connecting sleeve and the socket, forming an annular space between the connecting sleeve, the socket, and the elastic and leak-stopping sealing rings. Both the grouting port and the vent are connected to this annular space. Figure 3 , Figure 4 and Figure 7 Polyurea filler 11 is pumped into the annular space 10 through the grouting port 9. The polyurea filler 11 fills the annular space 10. The air in the annular space 10 is discharged through the exhaust port 8. After the air is discharged, the polyurea filler 11 overflows from the exhaust port 8. The grouting port 9 and the exhaust port 8 are blocked with a rubber plug to prevent the injected polyurea filler 11 from leaking, thus completing the grouting of the polyurea filler. When retrofitting existing sewage pipes, the concrete sewage pipes are already laid in the soil. Two concrete sewage pipes are connected in the soil via a connecting sleeve, forming a ring-shaped space between the connecting sleeve, the spigot, the elastic sealing ring, and the soil. During this process, workers or robots enter the concrete sewage pipes. Figure 8 Drill holes at the rear inlet 5 of the existing concrete sewage pipe 3 to form an exhaust port 8 and a grouting port 9. Both the exhaust port and the grouting port are connected to the annular space. Figure 9 Polyurea filler 11 is pumped into the annular space 10 through the grouting port 9. The polyurea filler 11 fills the annular space 10. The air in the annular space 10 is discharged through the exhaust port 8. After the air is discharged, the polyurea filler 11 overflows from the exhaust port 8. The grouting port 9 and the exhaust port 8 are blocked with a rubber plug to prevent the injected polyurea filler 11 from leaking, thus completing the grouting of the polyurea filler. After the polyurea filler is injected, a heating device such as a hot air blower is installed inside the socket 5 to heat the inner wall of the socket 5 and raise its temperature. The heat is transferred from the socket 5 to the polyurea filler 11 in the annular space 10, causing the polyurea filler 11 to heat up and accelerate its curing process, thereby improving construction efficiency. After curing, the polyurea filler 11 forms a sealing strip 13 between the socket 5 and the connecting sleeve 6. In this invention, the polyurea filler 11 is made of polyurea material, which has good fluidity and can well fill the annular space 10, forming a seal on the outside of the elastic sealing ring 7. The sealing strip 13 prevents sewage leakage. Simultaneously, the material properties of polyurea ensure a more reliable bond between the cured polyurea filler 11 and the socket 5 and connecting sleeve 6, guaranteeing the sealing effectiveness of the sealing strip 13. Furthermore, after curing, the polyurea filler 11 is essentially not under pressure, which helps slow down the rate of elastic modulus decay of the newly formed sealing strip 13, allowing it to maintain good elasticity over a long period. When the concrete sewage pipe 3 undergoes soil settlement, the sealing strip 13 can elastically deform, maintaining the seal between the connecting sleeve 6 and the socket 5 and preventing sewage leakage. In newly laid sewage pipes, after the polyurea filler has cured, the concrete sewage pipe is advanced into the soil.

[0026] In one embodiment, the nominal diameter of the concrete sewage pipe 3 is D. When D <= 600 mm, the volume of the annular space 10 is small, making it easy to fill with polyurea filler 11. Therefore, there is only one grouting port 9, located near the lower side of the spigot 5. When D > 600 mm, the volume of the annular space 10 is larger, and there are at least two grouting ports 9. One of the grouting ports 9 is located near the lower side of the spigot 5. When injecting polyurea filler 11, multiple grouting ports 9 inject polyurea filler 11 simultaneously, increasing the injection speed and density of polyurea filler 11. The vent 8 is located near the upper side of the spigot 5 for easy venting.

[0027] In one embodiment, when the above method is used for newly laid sewage pipelines, when D <= 1200 mm, it is inconvenient for workers or robots to enter the concrete sewage pipeline. The grouting port and the exhaust port are arranged on the connecting sleeve, and the grouting port is exposed outside the concrete sewage pipeline, which is convenient for injecting polyurea filler from the outside; when D > 1200 mm, it is convenient for workers or robots to enter the concrete sewage pipeline. The grouting port and the exhaust port are arranged on the socket, and the grouting port and the exhaust port are exposed inside the concrete sewage pipeline, and the polyurea filler is injected from the inside.

[0028] In one embodiment, the diameter of the grouting port 9 is d, and 20 mm < d < 50 mm.

[0029] In one embodiment, a manual grouting pump or an electric grouting device is used to pump the polyurea filler 11, and the grouting pressure is P, 0.2 MPa <= P <= 0.5 MPa, so as to control the pouring speed of the polyurea filler 11 and improve the pouring quality of the polyurea filler 11.

[0030] In one embodiment, when the above method is used for the renovation of existing sewage pipelines, such as Figure 8 , since the concrete sewage pipeline has been pre-laid in the soil body, and its end only has an elastic sealing ring, a gap 12 is formed at one end of the annular space far from the elastic sealing ring. Specifically, the gap is located between the front end of the connecting sleeve and the pipe body end face. In order to reduce the penetration of the polyurea filler into the soil through the gap, when pumping the polyurea filler 11, the temperature of the polyurea filler 11 is T, 10 °C < T < 20 °C. In this temperature range, on the premise of ensuring the fluidity of the polyurea filler 11 and facilitating pouring, by reducing the temperature of the polyurea filler 11, the viscosity of the polyurea filler 11 is increased, so as to reduce the penetration of the polyurea filler 11 into the surrounding soil body, and further improve the density of the polyurea filler 11 in the annular space 10 and enhance the sealing effect.

[0031] In one embodiment, when heating the socket 5, the temperature of the socket 5 is increased at a rate of 2 - 3 °C per minute, so that the temperature of the polyurea filler 11 rises slowly, in order to prevent the polyurea filler 11 from curing unevenly due to too fast temperature rise. When the temperature is increased by 5 °C each time, the temperature rise is paused for 10 minutes to reduce the temperature difference between the polyurea filler 11 and the socket 5. After the temperature of the socket 5 rises to 40 °C, the temperature is maintained for 1 - 2 hours, so that the polyurea filler 11 reacts quickly and cures to form a sealing band. After turning off the heating device, the sealing band cools naturally and the strength of the sealing band is formed.

[0032] Finally, it is noted that the method proposed in the present invention is mainly applicable to concrete sewage pipelines laid by trenchless pipe jacking construction. In addition, it is also equally applicable to pipelines for water supply, rainwater, gas, electricity and other purposes.

[0033] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for improving the sealing performance of flexible connections in concrete sewage pipes, characterized in that, The concrete sewage pipe includes a pipe body, a spigot, a connecting sleeve, and an elastic sealing ring. The spigot is located at both ends of the pipe body. The connecting sleeve is sealed and installed on the spigot at the front end of the pipe body, and the elastic sealing ring is installed on the spigot at the rear end of the pipe body. The above methods are applicable to both newly laid sewage pipes and the renovation of existing sewage pipes; When used for laying new sewage pipes, a leak-stopping sealing ring is pre-installed on the front side of the elastic sealing ring at the rear end of the concrete sewage pipe spigot. An air vent and a grouting port are pre-set at the spigot or connecting sleeve at the rear end of the concrete sewage pipe. When the above method is performed, two adjacent concrete sewage pipes are connected by a connecting sleeve before entering the soil. An annular space is formed between the connecting sleeve, spigot, elastic sealing ring and leak-stopping sealing ring. When modifying existing sewage pipes, two concrete sewage pipes are connected in the soil by a connecting sleeve. An annular space is formed between the connecting sleeve, the spigot, the elastic sealing ring and the soil. When the above method is performed, a hole is drilled at the spigot of the rear end of the concrete sewage pipe to form an air vent and a grouting port. Polyurea filler is pumped into the annular space through the grouting port. After the polyurea filler fills the annular space and overflows from the vent, it blocks the grouting port and the vent. The insertion port is heated, and after the polyurea filler solidifies, it forms a sealing strip between the insertion port and the connecting sleeve.

2. The method for improving the sealing performance of flexible connections in concrete sewage pipes according to claim 1, characterized in that, The nominal diameter of the concrete sewage pipe is D. When D <= 600 mm, there is one grouting port, located near the lower side of the spigot. When D > 600 mm, there are at least two grouting ports, one of which is located near the lower side of the spigot. The vent is located near the upper side of the spigot.

3. The method for improving the sealing performance of flexible connections in concrete sewage pipes according to claim 1, characterized in that, When the above method is used for laying new sewage pipes, if D<=1200mm, the grouting port and the venting port are set on the connecting sleeve; if D>1200mm, the grouting port and the venting port are set on the socket.

4. The method for improving the sealing performance of flexible connections in concrete sewage pipes according to claim 1, characterized in that, The diameter of the grouting port is d, 20mm. <d<50mm。 5. The method for improving the sealing performance of flexible connections in concrete sewage pipes according to claim 1, characterized in that, The polyurea filler is pumped using a manual grouting pump or an electric grouting device, with a grouting pressure of P, where 0.2MPa <= P <= 0.5MPa.

6. The method for improving the sealing performance of flexible connections in concrete sewage pipes according to claim 1, characterized in that, When the above method is used for the renovation of existing sewage pipelines, the temperature of the polyurea packing is T, 10℃, during pumping. <T<20℃。 7. The method for improving the sealing performance of flexible connections in concrete sewage pipes according to claim 1, characterized in that, When heating the socket, increase the socket temperature at a rate of 2~3℃ / minute. After each 5℃ increase, pause the temperature rise for 10 minutes. When the socket temperature reaches 40℃, maintain the temperature for 1-2 hours, and then turn off the heating equipment.

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