Non-excavation pipeline joint repairing method for rapid flexible joint of modular pipeline

Abstract

The invention provides a non-excavation pipeline joint repairing method for a rapid flexible joint of a modular pipeline, which is used for repairing continuous pipeline defects of a glass reinforced plastic pipe and comprises the following steps of: arranging a construction site; a to-be-constructed pipeline is safely treated; a step of confirming a to-be-repaired range; confirming the number of repairing channels in the to-be-repaired range; measuring the internal perimeter and crack width of the pipeline; the method further comprises the following steps: preparing a flexible restoration body of the modularized glass sand inclusion pipe according to the length to be repaired, the inner diameter of the pipeline and the quantity; transporting the flexible restoration body of the modularized glass sand inclusion pipe to a repairing point; and mounting the stainless steel ring. The problem that a conventional pipeline rapid flexible joint technology can only conduct point repair on defect points in order to give consideration to the pressure bearing capacity and the repair range is solved, and the pipeline defects can be continuously repaired through the modularized rubber ring.

Description

Technical Field

[0001] This invention relates to the field of fiberglass pipe repair in municipal pipelines, and more particularly to a method for repairing trenchless pipe joints using modular quick flexible joints. Background Technology

[0002] In the reinforcement project of DN2000 raw water supply at Xinyuan Road Station on Line 20, our company discovered that part of the repair section of Well J20 was made of fiberglass pipe, which could not be repaired using the traditional AMEX repair process. This is because conventional pipeline quick flexible joint technology can only repair the defect points in order to balance pressure bearing capacity and repair range. Since there were continuous pipeline defects in the fiberglass pipe in the repair section of this project, the existing repair technology was powerless in this project. Summary of the Invention

[0003] The purpose of this invention is to provide a modular pipeline quick flexible joint trenchless pipeline joint repair method, which can simultaneously repair and reinforce defects in continuous fiberglass pipes in a rapid and convenient manner.

[0004] This invention proposes a modular, quick-connect flexible joint method for repairing trenchless pipe joints. This method is used to repair defects in continuous fiberglass reinforced plastic (FRP) pipes. The method includes: a construction site layout step; a safety treatment step for the pipe to be repaired; a step to confirm the repair area; a step to confirm the number of repair sections within the repair area; and a step to measure the internal circumference and crack width of the pipe. The method is characterized by further including: (1) Prepare modular glass-reinforced flexible repair bodies according to the length to be repaired, the inner diameter of the pipe, and the quantity; The modular glass-filled sand tube flexible repair body has two mutually staggered B-type superimposed inner expansion ring assemblies, an A-type superimposed inner expansion ring unit staggered with the B-type superimposed inner expansion ring, and four stainless steel water-stop ring units. Two of the stainless steel water-stop rings are distributed on the inner surface of the end of the modular glass-filled sand tube flexible repair body, and the remaining two stainless steel water-stop rings are distributed at the splicing position of the superimposed inner expansion ring in the modular glass-filled sand tube flexible repair body. (2) The steps for transporting the modular glass-filled sand tube flexible repair body to the repair point; (3) Support the No. 1 rubber ring in the modular glass-filled sand pipe flexible repair body so that the No. 1 rubber ring fits against the pipe wall; (4) Spread the stainless steel water-stop ring along the outer flange opening of the No. 1 rubber ring; (5) The steps for installing the stainless steel ring include: 5.1 With the stainless steel waterstop ring fully extended and the gap between the ends of the two stainless steel waterstop rings greater than 20mm, install the hydraulic tool; 5.2 Place the hydraulic tool at the opened port, install a steel support on the hydraulic tool to support the top of the steel ring, and while the hydraulic tool is pressurized, use a hammer to strike the stainless steel ring. The hammer surface should be in horizontal contact with the ring surface, and the hammering points should be evenly distributed on the ring so that the stainless steel ring sinks into the rubber ring groove. 5.3 Pressurize to 0.4MPa and continue hammering the stainless steel ring until the hydraulic gauge reading of the hydraulic tool stops falling. Select the appropriate metal insert according to the spread distance and insert it into the insert limit groove. (6) Overlap the groove of the No. 2 rubber ring onto the protrusion of the No. 1 rubber ring to support it; (7) Install a stainless steel water-stop ring at the overlap of No. 1 and No. 2 rubber rings; (8) Following the same steps, overlap the No. 3 rubber ring with the No. 2 rubber ring and install the remaining two stainless steel water-stop rings; (9) Steps to confirm the airtightness at the air valve.

[0005] The modular pipe quick flexible joint trenchless pipe joint repair method provided by the present invention also includes a pretreatment step, which includes pipe grinding and applying a layer of food-grade epoxy resin topcoat to the inner wall surface of the ground glass-filled sand pipe.

[0006] It also includes a pretreatment step, which includes grinding the pipe and applying a food-grade epoxy resin topcoat to the inner wall surface of the ground glass-reinforced pipe.

[0007] In the modular pipe quick flexible joint non-excavation pipe joint repair method provided by the present invention, the top of the hydraulic expander of the hydraulic tool (5) is provided with a square metal block fixed seat (8), and the square metal block fixed seat (8) is vertically installed with a radial support device (9).

[0008] In the modular pipe quick flexible joint trenchless pipe joint repair method provided by the present invention, the A-type superimposed inner expansion ring (1) of the A-type superimposed inner expansion ring unit has an A-type superimposed inner expansion ring intermediate body (1a). The A-type superimposed inner expansion ring intermediate body has a first end (1-1) and a second end (1-2) of the A-type superimposed inner expansion ring symmetrically distributed at both ends. The back of the first end (1-1) of the A-type superimposed inner expansion ring has a first recessed part (1-1a). The lower surface of the first end (1-1) of the A-type superimposed inner expansion ring has symmetrical inclined platform protrusions (1-1b). Three inclined platform intermediate protrusions (1-1c) are evenly distributed in the middle of the two inclined platform protrusions (1-1b). There is a U-shaped groove between the two inclined platform intermediate protrusions (1-1c). A C-shaped outer protrusion is provided at the center of the B-type superimposed inner expansion ring intermediate body. The two ends of the B-type superimposed inner expansion ring intermediate body are the first end (2-1) and the second end (2-2) of the B-type superimposed inner expansion ring. The structure of the first end (2-1) of the B-type superimposed inner expansion ring is the same as that of the first end (1-1) of the A-type superimposed inner expansion ring. The second end (2-2) of the B-type superimposed inner expansion ring has a ridge with the same thickness as the B-type superimposed inner expansion ring intermediate body. Three rectangular protrusions (2-2a) are evenly distributed on the surface of the ridge. The spacing between the rectangular protrusions is adapted to the width of the protrusion (1-1c) in the middle of the inclined platform.

[0009] The modular pipeline quick flexible joint repair method for trenchless pipeline joints provided by the present invention includes the steps of preliminary survey, pre-installation preparation, inner ring installation, rubber ring laying, and pressure testing. In the preliminary survey steps, after the pipeline is shut down, the remaining water in the pipeline is completely drained, an exhaust system is installed, and the air quality in the pipeline is tested using an air quality detector. Once the air quality meets the standards, construction personnel are sent into the pipeline to conduct an on-site survey of the pipeline joints to be repaired, number them, and understand the actual damage to the fiberglass pipeline joints. Each joint and circumferential crack that needs to be repaired is confirmed, and the width and depth of each joint crack are determined. When confirming the pipeline joints that need to be repaired, the condition of the joint, the degree of corrosion, the degree of pollution, solid and loose deposits, wall thickness, etc. are also recorded to provide guidance for the pre-treatment before installation. In the pre-installation preparation steps, before installing the inner expansion ring, the air quality inside the pipeline is first checked with an air detector to ensure it meets the standards, and then construction personnel are sent down into the pipeline to remove the silt inside. In the process of installing the inner expansion ring, before the installation of the inner expansion ring begins, a layer of food-grade epoxy resin paint is applied to the inner wall surface of the pipe after grinding. This paint can play a role in preventing rust and corrosion on the inner wall of the fiberglass pipe. In the step of laying the rubber ring, tighten the bottom air valve with a key, and attach the rubber ring tightly to the joint. Take a 14mm×8mm×2mm steel sheet and place it on the groove at the bottom of the rubber ring. First, install a stainless steel ring with a larger diameter. Place the stainless steel ring roughly in the groove of the rubber ring and gradually open the steel ring until the two ends of the ring bottom are joined together on the pad. Then, use a pry bar to drive wedges into the bottom of the joined stainless steel ring from small to large to facilitate the placement of the hydraulic jack. During installation, first place the hydraulic jack at the port that has been opened by the wedge, and start pressurizing to 0.15 MPa. Use a hammer to lightly tap the stainless steel ring and adjust its position so that it is in the groove of the rubber ring. Install a steel support on the hydraulic jack to support the top of the steel ring. Continue to pressurize to 0.2 MPa, and use a hammer to strike the stainless steel ring forcefully. The hammer surface should be in horizontal contact with the ring surface, and the hammer points should be evenly distributed on the ring so that the stainless steel ring is completely embedded in the groove of the rubber ring. Then, pressurize to 0.4 MPa and continue to hammer the stainless steel ring until the hydraulic gauge reading stops dropping. Since the stainless steel ring has been stretched open, select a suitable stainless steel wedge based on experience to support the load, replacing the previously driven wedge. Finally, release the pressure, disassemble the steel support and hydraulic jack, and use a hammer to hammer the bottom stainless steel wedge to make it fit into the groove, completing the installation. The same method is used for smaller diameter stainless steel rings to form a permanent mechanical seal.

[0010] Before the pressure test, prepare a miniature air compressor with a portable air canister (10L capacity, 0.8MPa working pressure). Fill the canister with compressed air. During the test, first open the valve on the rubber ring, connect the air outlet of the portable air canister to the valve, and begin inflation. Maintain the working pressure at 0.05MPa. After inflation, begin leak testing. Apply soapy water to both ends of the rubber ring secured by the steel ring and check for continuous, obvious bubbles. If the pressure does not drop, the test is successful. If bubbles appear, reinstall and retest until the test is successful. Finally, release the air and tighten the valve on the rubber ring with a key. The pressure test is now complete.

[0011] Compared with existing technologies, this invention solves the problem that conventional pipeline quick flexible joint technology can only perform point repairs on defects in order to balance pressure bearing capacity and repair range. Through modular rubber rings, pipeline defects can be continuously repaired. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the construction pipeline route for the modular pipeline quick flexible joint trenchless pipeline joint repair method in the first embodiment of the present invention.

[0013] Figure 2 This is a cross-sectional view of the modular glass-filled sand pipe flexible repair body in the trenchless pipe joint repair method of the modular pipe quick flexible joint in the first embodiment of the present invention.

[0014] Figure 3 This is a cross-sectional view of the type A superimposed internal expansion ring applicable to the trenchless pipe joint repair method of the modular pipe quick flexible joint in the first embodiment of the present invention.

[0015] Figure 4This is a cross-sectional view of the B-type superimposed internal expansion ring applicable to the trenchless pipe joint repair method of the modular pipe quick flexible joint in the first embodiment of the present invention.

[0016] Figure 5 This is a cross-sectional view of the modular glass-filled sand pipe flexible repair body installed in the non-excavation pipe joint repair method of the modular pipe quick flexible joint in the first embodiment of the present invention.

[0017] Figure 6 This is a diagram showing the effect of supporting the No. 1 rubber ring so that it fits against the pipe wall.

[0018] Figure 7 This is a diagram showing the effect of the stainless steel water-stop ring being spread out along the outer flange of the No. 1 rubber ring.

[0019] Figure 8 This is a cross-sectional view showing the installation effect of the stainless steel water-stop ring and the modular rubber ring.

[0020] Figure 9 This is a rendering of a hydraulic tool installed between the ends of two stainless steel water-stop rings.

[0021] Figure 10 An image showing the effect of a hammer striking a stainless steel ring.

[0022] Figure 11 This is a diagram showing the effect after the metal insert is in place.

[0023] Figure 12 This is a diagram showing the effect of overlapping the recessed part of the No. 2 rubber ring with the protruding part of the No. 1 rubber ring.

[0024] Figure 13 This is a rendering showing the effect of installing a stainless steel water-stop ring at the overlap of rubber rings No. 1 and No. 2.

[0025] Figure 14 This is a diagram showing the effect of overlapping rubber ring #3 with rubber ring #2.

[0026] Figure 15 This is a rendering showing the effect of overlapping rubber ring #3 with rubber ring #2 and installing the remaining two stainless steel water-stop rings.

[0027] Figure 16 This is a rendering of the completed assembly of a modular glass-reinforced flexible repair tube.

[0028] Figure 17 A schematic diagram of a stainless steel water-stop ring with an end bearing block at the end that abuts against a metal insert.

[0029] Figure 18 This is a process flow diagram of the present invention. Detailed Implementation

[0030] The present invention will now be described in more detail with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0031] Figure 1 The present invention describes a pipeline P and the manholes along the pipeline in a DN2000 raw water reinforcement project. Pipeline P runs along a city road. The manholes are designated as manholes J16 (No. 16), J20 (No. 20), J23 (No. 23), J26 (No. 26), and J29 (No. 29). The area requiring repair using this invention is the pipeline (all DN2000 fiberglass pipe sections of raw water) between manholes J20 (No. 20) and J29 (No. 29), with a repair distance of approximately 800m.

[0032] The modular pipe quick flexible joint trenchless pipe joint repair method provided by this invention is used to repair defects in continuous FRP pipes. The specific method is as follows: (a) Steps for arranging the construction site exist Figure 1 In the DN2000 FRP pipe section of raw water pipe to be repaired, access to the pipe interior is via pre-installed DN800 manholes in both pipe shafts (J20, No. 20 and J29). During pumping, the drainage valves in pipe shafts (J23 and J26 on the north side) are opened to pump water out. After pumping is complete, the pipe is ventilated and a gas test is performed. Once the gas test is passed, access to the DN2000 FRP pipe section for repairs is initiated.

[0033] The construction area is completely enclosed with water-filled barriers. Temporary access roads are provided on site, and a generator is used for temporary power supply. A 0.4m wide and 0.2m high drainage ditch is installed around the perimeter of the site to prevent surface water from flowing into the pit and pipes. A rain shelter is provided on site to cover the work pit area.

[0034] (II) Steps for safety treatment of pipelines under construction After the pipeline pumping operation is completed, if a large amount of garbage and silt is found inside the raw water pipe, measures will be taken to remove it, and the silt and other debris will be lifted out of the pipeline and transported away in a timely manner. The site will be staffed 24 hours a day after construction begins.

[0035] Before entering the pipeline for construction, first connect the air compressor's outlet pipe to the J16 exhaust port to input air, then use an axial flow blower to guide the airflow and simultaneously expel any residual gas in the pipeline. Before entering the pipeline, a gas testing instrument must be used to determine whether there are any toxic or harmful gases such as hydrogen sulfide inside. The access pits and pipeline ladders must be sturdy and reliable, with handrails and fall prevention measures. The work platform erected inside the pipeline must be stable.

[0036] (III) Steps to confirm the scope of repair exist Figure 1 The DN2000 fiberglass pipe section of raw water pipe to be repaired shown is located between pipe well J20 (No. 20) and pipe well J29 (No. 29), with a repair distance of approximately 800m. The specific number of pipes to be repaired within this 800m repair range will be investigated in subsequent steps.

[0037] (iv) Steps for confirming the number of repairs within the scope to be repaired As mentioned earlier, in the 800m stretch of fiberglass pipes to be repaired, each pipe joint or crack is counted as one repair. Figure 1 In the raw water pipe section of DN2000 fiberglass pipe to be repaired shown, there are 36 DN2000 fiberglass pipes to be repaired between pipe well J20 of No. 20 and pipe well J23 of No. 23, and 7 DN2000 fiberglass pipes to be repaired between pipe well J29 of No. 29 and pipe well J26 of No. 26, for a total of 43 repairs. Typical defects in this type of repair include, but are not limited to: (1) circumferential intermittent damage between adjacent fiberglass pipes (connection); (2) circumferential bulging damage defects in fiberglass pipes, which are manifested as bulging protrusions or long cracks.

[0038] (v) Steps for measuring the internal circumference and crack width of the pipe The method used to measure and number the internal circumference and crack width of the pipe is as follows: To ensure the rubber ring seal is the correct length for the pipe, the internal circumference must be measured twice: once from top to bottom and once from left to right. If the pipe has a special shape, such as an oval or square, installers can use a measuring tape to measure the internal circumference.

[0039] Select appropriate rubber seals based on the internal circumference of the pipe. The stretch of the rubber should be approximately 30% of its own length.

[0040] Construction personnel entered the pipeline to conduct an on-site inspection, numbering the pipe joints to be repaired and assessing the actual extent of damage to the fiberglass pipe joints. They confirmed each joint requiring repair and any circumferential cracks, noting the width and depth of each crack. When confirming the pipe joints requiring repair, they also recorded the condition of the joint, the degree of corrosion, the degree of contamination, solid and loose deposits, and the wall thickness, providing guidance for pre-installation treatment.

[0041] It should be noted that the pretreatment method is to apply a layer of food-grade epoxy resin topcoat to the inner wall surface of the pipe after grinding. This paint can play a role in preventing rust and corrosion on the inner wall of the fiberglass pipe.

[0042] (vi) Prepare modular glass-reinforced flexible repair bodies according to the length, inner diameter, and quantity of pipes to be repaired. Figure 2 The core repair component of this invention, a modular glass-filled sand tube flexible repair body S, is provided. This modular glass-filled sand tube flexible repair body has two mutually staggered B-type superimposed inner expansion ring assemblies (which are composed of two B-type superimposed inner expansion rings 2), an A-type superimposed inner expansion ring unit (which is composed of one A-type superimposed inner expansion ring 1) that is staggered with the B-type superimposed inner expansion rings, and a four stainless steel water-stop ring unit (which is composed of four stainless steel water-stop rings 3). Two stainless steel water-stop rings are distributed on the inner surface of the end of the modular glass-filled sand tube flexible repair body, and the remaining two stainless steel water-stop rings are distributed at the splicing positions of the superimposed inner expansion rings in the modular glass-filled sand tube flexible repair body.

[0043] Figure 2 and Figure 3 Cross-sectional views of type A stacked inner expansion ring 1 and type B stacked inner expansion ring 2 in a modular glass-reinforced flexible repair are presented. Figure 2It can be seen that the overall length of the rubber-made A-type stacked inner expansion ring 1 is 400mm and the thickness is 8mm, while the length of the A-type stacked inner expansion ring intermediate body 1a is 260mm. The A-type stacked inner expansion ring intermediate body 1a is a uniform thickness structure of 8mm. The A-type stacked inner expansion ring intermediate body has a C-shaped outer protrusion 1b at its center. At both ends of the A-type stacked inner expansion ring intermediate body 1a, there are A-type stacked inner expansion ring first end 1-1 and A-type stacked inner expansion ring second end 1-2. The back of the A-type stacked inner expansion ring first end 1-1 has a first recessed portion 1-1a. The first recessed portion can serve as the installation position for the stainless steel water-stop ring. Since this position has a structure with a stop at both ends, it can effectively prevent the stainless steel water-stop ring from slipping after installation, greatly improving the installation stability and reliability of the stainless steel water-stop ring at the A-type stacked inner expansion ring. The lower surface of the first end 1-1 of the A-type superimposed inner expansion ring has symmetrical inclined protrusions 1-1b. When the inclined protrusions are installed on the inner wall of the fiberglass pipe, they can first allow the contact section of the inner wall of the fiberglass pipe where the first end is located to have two inwardly tapered ends. Three inclined middle protrusions 1-1c are evenly distributed between the two inclined protrusions 1-1b. There is a U-shaped groove between each pair of inclined middle protrusions 1-1c. The surface of the inclined middle protrusions has large arc ridges distributed at both ends, and between the large arc ridges are small arc concave parts. The radius of the arc of the small arc concave part is smaller than the radius of the arc of the large arc ridge. This design of large arc ridges at both ends allows the arc ridges to deform better after extrusion and deformation to contact the sealing surface (such as the inner wall of the pipe). The small arc concave part in the middle can provide better deformation acceptance space for the large arc ridges. The structure of the second end 1-2 of the type A superimposed inner expansion ring is the same as that of the first end 1-1 of the type A superimposed inner expansion ring, and will not be described again here.

[0044] See also Figure 3The rubber B-type stacked inner expansion ring 2 is 400mm long and 8mm thick. The length of the middle body of the B-type stacked inner expansion ring is 260mm. A C-shaped outer bulge is set in the center of the middle body of the B-type stacked inner expansion ring. The two ends of the middle body of the B-type stacked inner expansion ring are the first end 2-1 and the second end 2-2 of the B-type stacked inner expansion ring. The structure of the first end 2-1 of the B-type stacked inner expansion ring is the same as that of the first end 1-1 of the A-type stacked inner expansion ring. The same structure is beneficial to the mold processing requirements and has better compatibility in the later installation and use. The second end 2-2 of the B-type stacked inner expansion ring has a ridge with the same thickness as the middle body of the B-type stacked inner expansion ring. Three rectangular protrusions 2-2a are evenly distributed on the surface of the ridge. The spacing between the rectangular protrusions is adapted to the width of the middle protrusion 1-1c of the inclined platform to meet the tight fit effect. Note that the depth of the gap between the rectangular protrusions needs to be less than the height of the middle protrusion 1-1c of the inclined platform. This allows the middle protrusion 1-1c of the inclined platform to enter the gap between the rectangular protrusions and be squeezed and deformed to fill the area, thereby improving the sealing effect and the stability of the structure.

[0045] It should be noted that the intermediate body of both the Type B and Type A stacked inner expansion rings is a continuous extension structure up to 260mm long. In the process of repairing long-stroke defects, it can effectively utilize its own structural characteristics to complete the sealing and plugging repair. Its own flexibility also meets the structural deformation requirements of the modular glass-filled sand tube flexible repair body during the repair.

[0046] It is worth mentioning that the modular glass-reinforced sand-filled pipe flexible repair body here, after being installed by the construction personnel, achieves the following effect when installed on fiberglass pipe B (the glass-reinforced sand-filled pipe has the same meaning throughout the text): Figure 5 As shown, the length of the cut fiberglass pipe is 1050mm. The modular fiberglass reinforced plastic (FRP) flexible repair body S in the figure repairs its continuous damage defect. The diameter of FRP pipe B is 2000mm, and the damage defect is close to 1000mm. Here, [the repair is...]. Figure 5 The three modular rubber rings (i.e., two B-type stacked inner expansion rings 2 and one A-type stacked inner expansion ring 1) are designated as rubber ring 1, rubber ring 2, and rubber ring 3 from left to right.

[0047] Will Figure 5In the two mutually staggered and spliced ​​B-type superimposed inner expansion ring assemblies, the B-type superimposed inner expansion rings are defined as the first B-type superimposed inner expansion ring (i.e., the No. 1 rubber ring mentioned above) and the second B-type superimposed inner expansion ring (i.e., the No. 2 rubber ring mentioned above). The first end 2-1 of the first B-type superimposed inner expansion ring is attached to the inner wall of the glass-filled tube, while the second end 2-2 of the first B-type superimposed inner expansion ring is away from the inner wall of the glass-filled tube and superimposed and spliced ​​with the first end 2-1 of the second B-type superimposed inner expansion ring. The second end 2-2 of the second B-type superimposed inner expansion ring is away from the inner wall of the glass-filled tube and spliced ​​with the first end 1-1 of the A-type superimposed inner expansion ring, while the second end 1-2 of the A-type superimposed inner expansion ring is attached to the inner wall of the glass-filled tube.

[0048] (vii) Steps for transporting the modular glass-reinforced flexible repair to the repair site A set of modular glass-reinforced flexible repair pipes is transported to the repair point and placed sequentially in the direction of water flow. Air valves are then installed. This method requires three modular rubber rings. The air valves are installed on the C-shaped outer protrusions of these three modular rubber rings. The purpose of installing the air valves is to test the airtightness of the entire repair structure after installation. The presence of the C-shaped outer protrusions makes the installation of the air valve structure more convenient.

[0049] The modular glass-filled sand pipe flexible repair body consists of three modular rubber rings (i.e., two B-type stacked internal expansion rings and one A-type stacked internal expansion ring) and four stainless steel water-stop ring units, which enter the pipe to be repaired from the working well (pipe well) and are transported to the repair point through the inside of the pipe.

[0050] (viii) See Figure 6 As shown, the No. 1 rubber ring (i.e., the first B-type superimposed inner expansion ring 2) in the modular glass-reinforced flexible repair body is supported so that the No. 1 rubber ring is in contact with the pipe wall. At this time, the No. 1 rubber ring is not supported at all and requires 2-3 operators to hold it in place to keep the No. 1 rubber ring in contact with the pipe wall.

[0051] (ix) See also Figure 7 As shown, the first stainless steel water-stop ring 3 is spread open along the outer flange of the No. 1 rubber ring. At this time, the first stainless steel water-stop ring plays a supporting role for the No. 1 rubber ring.

[0052] (x) The steps for installing the stainless steel ring include: See Figure 8 To install hydraulic tools, fully open the stainless steel waterstop ring 3, ensuring the gap between the ends of the two stainless steel waterstop rings is greater than 20mm. For instructions on using hydraulic tools, please refer to [link to relevant documentation]. Figure 9As shown in the diagram, a hydraulic tool 5 (e.g., a hydraulic jack) is placed at the opened end, and a steel support is installed on the hydraulic tool to support the top of the steel ring. While the hydraulic tool applies pressure, a tool hammer 6 is used to strike the stainless steel ring (e.g., ...). Figure 10 As shown), the hammer face makes horizontal contact with the ring surface, and the hammering points are evenly distributed on the ring, causing the stainless steel ring to sink into the rubber ring groove. The hydraulic tool is pressurized to 0.4 MPa, and the stainless steel ring is continued to be hammered until the hydraulic gauge reading of the hydraulic tool no longer drops. Based on the distance the ring is spread, a suitable metal insert 4 is inserted into the insert limiting groove (e.g., ...). Figure 11 As shown), stainless steel water-stop rings at both ends of the metal insert 4 are provided with insert limiting protrusions 7, forming a permanent mechanical seal ring through this stainless steel water-stop ring assembly. Of course, see also... Figure 17 An end bearing block 3c can be provided at the end of the stainless steel water-stop ring that abuts against the metal insert. A compression spring 3d is provided between the end bearing block and the stainless steel water-stop ring. For example, a matching compression spring assembly through hole is provided between the end bearing block and the stainless steel water-stop ring, and one end of the compression spring is fixed to the stainless steel water-stop ring. After installation, the compression spring can be used to forcefully compress the metal insert 3b, thereby improving the compression sealing effect of the water-stop ring. More importantly, the compression spring can provide stress relief for the entire stainless steel water-stop ring. In addition, a sliding foot that can move along the suspension part can be provided at the top of the end bearing block 3c, which can improve the guiding movement capability of the end bearing block.

[0053] exist Figure 9 As can be seen from the image, the top of the hydraulic expander of the hydraulic tool 5 is provided with a square metal block fixed seat 8. The square metal block fixed seat 8 is vertically mounted with a radial support device 9. The main body of the radial support device 9 has a threaded first rod-shaped part and a second rod-shaped part that cooperates with the first rod-shaped part and has an internal thread. The first rod-shaped part is vertically provided with a straight rotating rod. The length of the entire main body is adjusted by driving the first rod-shaped part in the inner cylinder of the second rod-shaped part through the straight rotating rod.

[0054] (xi) See also Figure 12 The groove of the No. 2 rubber ring (i.e., the second B-type superimposed inner expansion ring 2) is overlapped with the protrusion of the No. 1 rubber ring to support it, forming the second ring of the modular glass-filled sand tube flexible repair body.

[0055] (xii) See also Figure 13 Install a stainless steel water-stop ring 3 at the overlap of rubber ring 1 and rubber ring 2.

[0056] (xiii) See Figure 14-15Following the same steps, overlap rubber ring #3 with rubber ring #2 and install the remaining two stainless steel water-stop rings. Once rubber ring #3 is in place, it forms the third ring of the modular glass-reinforced flexible repair. After installing the remaining two stainless steel water-stop rings, the assembly of the modular glass-reinforced flexible repair is complete. See [link to product details] for the specific effect. Figure 16 .

[0057] (xiv) Steps to confirm the airtightness at the air valve.

[0058] Pressure testing is a crucial inspection of installation quality. Before the test, prepare a miniature air compressor with a portable air canister (10L capacity, 0.8MPa working pressure). Fill the canister with compressed air. During the test, first open the valve on the rubber ring, connect the air outlet of the portable air canister to the valve, and begin inflation, maintaining a working pressure of 0.05MPa. After inflation, begin leak testing. Apply soapy water to both ends of the rubber ring secured by the steel ring and observe for continuous, obvious bubbles. If the pressure does not drop, the test is successful. If bubbles appear, reinstall and retest until successful. Finally, release the air; tighten the valve on the rubber ring with a key to complete the pressure test.

[0059] The second embodiment of the present invention provides a method for repairing trenchless pipe joints using modular quick flexible joints, which includes preparatory work before construction of lap-type pipe repair and repair of lap-type quick flexible joints.

[0060] 1. Preparatory work before repairing overlapping pipes 1.1 Construction Site Layout The construction area is completely enclosed with water-filled barriers, and temporary access roads are provided on site. Temporary power is supplied by a generator. A 0.4m wide and 0.2m high intercepting ditch is installed around the perimeter of the site to prevent surface water from flowing into the pits and pipes. A rain shelter is provided on site to cover the work pit area.

[0061] 1.2. Construction Precautions After the pipeline pumping operation is completed, if a large amount of garbage and silt is found inside the raw water pipe, measures will be taken to remove it, and the silt and other debris will be lifted out of the pipeline and transported away in a timely manner. The site will be staffed 24 hours a day after construction begins.

[0062] Before entering the pipeline for construction, first connect the air compressor's outlet pipe to the J17 exhaust port to input air, then use an axial flow blower to guide the airflow and simultaneously expel any residual gas in the pipeline. Before entering the pipeline, a gas testing instrument must be used to determine whether there are any toxic or harmful gases such as hydrogen sulfide inside. The access pits and pipeline ladders must be sturdy and reliable, with handrails and fall prevention measures. The work platform erected inside the pipeline must be stable.

[0063] 2. Repair of overlapping pipe quick-connect flexible joints 2.1 Repair process for lap-type pipe quick flexible joints This repair of FRP pipes mainly uses lap-type rubber expansion ring joint repair technology (the final number of joints will be determined based on the site conditions). The main materials are rubber sealing rings and expandable stainless steel fastening rings (the stainless steel fastening rings are generally no less than 80mm×8mm in size). Compared with the traditional quick flexible joint repair process for pipelines, this technology can repair FRP sand-filled pipes.

[0064] First, a set of three rubber sealing rings is placed at the location of the pipe welding joint. Then, four stainless steel rings are placed on top as an overlapping rubber expansion ring joint repair. A stainless steel wedge is inserted to support the load by hydraulic expansion, forming a permanent mechanical seal ring.

[0065] Every joint repaired using the lap-type quick flexible pipe joint technology must undergo an airtightness pressure test, which is a crucial inspection of the repair quality. Before the pressure test, a miniature air compressor must be prepared, with a test pressure of not less than 0.05 MPa. After inflating the joint, soapy water is applied to both ends of the rubber ring secured by the steel ring. Observe whether there are obvious and continuous bubbles. If there are none, it indicates that the pressure test is qualified. If the pressure test fails, the rubber expansion ring of the joint must be reinstalled and pressure tested again until the pressure test is qualified.

[0066] The rubber waterstops used in this project should generally be no less than 400 mm wide, and in special cases, they can be widened to over 500 mm (depending on the extent of damage to the pipe joints). The thickness should generally be no less than 6 mm. The technical specifications of the rubber waterstops meet the relevant requirements of the "Code for Construction and Acceptance of Water Supply and Drainage Pipeline Engineering" GB50268-2008 and the "Hygienic Standard for Rubber Products for Food Use" GB4806.1.

[0067] 2.2 Process Flow of Lap-Type Pipe Quick Flexible Joint See Figure 18 The process includes: opening manholes for ventilation → removing and cleaning sludge from inside the pipes → applying anti-corrosion paint to pipe joints → installing and reinforcing water-stop rings → pressure testing → final acceptance → sealing the manholes and allowing water to flow through. The following is a detailed description of the process.

[0068] Preliminary Survey: The preliminary survey is the first and crucial step in the process of this invention. After the pipeline is shut down, the remaining water inside is completely removed, an exhaust system is installed, and the air quality inside the pipeline is tested using an air quality detector. Once the air quality meets the standards, construction personnel are dispatched to the pipeline to conduct an on-site survey, numbering the pipe joints to be repaired and understanding the actual extent of damage to the fiberglass pipe joints. Each joint requiring repair and circumferential crack is confirmed, and the width and depth of each crack are determined. When confirming the pipe joints that need repair, the condition of the joint, the degree of corrosion, the degree of contamination, solid and loose deposits, and the wall thickness are also recorded to provide guidance for pre-installation treatment.

[0069] Preparation before installation: Before installing the internal expansion ring, first use an air quality detector to check that the air quality in the pipeline meets the standards, and then send construction personnel down into the pipeline to remove the silt inside.

[0070] Internal expansion ring installation: Before installing the internal expansion ring, apply a layer of food-grade epoxy resin topcoat to the polished inner wall surface of the pipe. This paint provides rust and corrosion protection for the inner wall of the fiberglass pipe.

[0071] Lay out the rubber ring and tighten the bottom valve with a key. Secure the rubber ring tightly to the seam. Place a 14mm x 8mm x 2mm steel sheet in the groove at the bottom of the rubber ring; this prevents the stainless steel ring from scratching the rubber ring when it expands. First, install the larger diameter stainless steel ring, roughly placing it in the groove of the rubber ring. Gradually expand the steel ring until the two ends at the bottom of the ring align with the washer. Then, use a pry bar to drive wedges into the bottom of the aligned stainless steel rings, from smallest to largest, to facilitate the placement of the hydraulic jack.

[0072] In this crucial installation step, first place the hydraulic jack at the opening propped open by the wedges and begin pressurizing to 0.15 MPa. Lightly tap the stainless steel ring with a hammer to adjust its position, ensuring it is within the rubber ring groove. Install a steel support on the hydraulic jack to hold the top of the steel ring in place. Continue pressurizing to 0.2 MPa and forcefully tap the stainless steel ring with the hammer, ensuring the hammer face is horizontally aligned with the ring surface and the impact points are evenly distributed across the ring, allowing the stainless steel ring to fully sink into the rubber ring groove.

[0073] Then, pressurize to 0.4 MPa and continue hammering the stainless steel ring until the hydraulic gauge reading stops dropping. Since the stainless steel ring has been stretched, select a suitable stainless steel wedge (30mm-108mm) based on experience, replacing the previously driven wedge, to support the load. Finally, release the pressure, disassemble the steel support and hydraulic jack, and use a hammer to strike the bottom stainless steel wedge to insert it into the groove, completing the installation. Smaller diameter stainless steel rings are processed in the same way to form a permanent mechanical seal.

[0074] Pressure Testing: Pressure testing is a crucial inspection of installation quality. Before testing, prepare a miniature air compressor with a portable air canister (10L capacity, 0.8MPa working pressure). Fill the canister with compressed air. During the test, first open the valve on the rubber ring, connect the air outlet of the portable air canister to the valve, and begin inflation, maintaining a working pressure of 0.05MPa. After inflation, begin leak testing. Apply soapy water to both ends of the rubber ring secured by the steel ring and observe for continuous, obvious bubbles. If the pressure does not drop, the test is successful. If bubbles appear, reinstall and retest until successful. Finally, release the air; tighten the valve on the rubber ring with a key. The pressure test is now complete.

[0075] Quality control requirements: (1) Material cutting and accessories a. Use special tools to lift the parts. Handle them with care during loading and unloading. During transportation, padded and secured to prevent collisions. Stack them in a convenient, flat and firm place. They must be padded securely when stacking. When using them, transport the pipe sections from top to bottom to ensure the safety of personnel passing through the construction area.

[0076] b. Before construction, first inspect the accessories.

[0077] c. During installation, the stainless steel ring and rubber ring surface must be cleaned thoroughly, free of dirt and burrs. Gloves should be worn when installing the rubber ring. Installation must not be stopped until it is completed.

[0078] d. When applying soapy water to the rubber seal, it should be applied immediately and evenly as specified, without any omissions or insufficient application. e. When installing the interface, use a stone pencil to determine the position of the rubber ring, number each interface, and record and check.

[0079] f. Rubber rings should be stored separately, protected from heavy pressure and kept away from oily substances and heat sources. When working on site, cover them with tarpaulin to prevent exposure to direct sunlight. g. After installation, ensure it is not twisted and inspect it.

[0080] h. The rubber ring must not be twisted after installation. When checked with a ruler, each point along the circumference should be parallel to the end face of the stainless steel ring, with an allowable deviation of 3mm.

[0081] i. Epoxy Resin Coating Application Requirements: 1) The coating is handled by a designated person, and the mixing ratio is strictly in accordance with the product instructions, especially the curing time, to ensure coating quality and curing time.

[0082] 2) The ambient temperature must not be lower than 5 degrees Celsius when performing external anti-corrosion operations.

[0083] 3) Apply the paint from top to bottom and left to right. Use an appropriate amount of paint on the brush. If there are rough edges, corners, or protrusions, sand them down before applying the paint.

[0084] Valve core installation requirements Attachment installation: The attachment mainly refers to the installation of the air valve core: (1) After disassembling the valve core, use a rubber hammer to tap the side with the air nozzle into the rubber ring from the inside, and then install the remaining half from the back. Tighten it with a wrench. After completion, ensure that it is firm and tight.

[0085] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. A modular, quick-connect flexible pipe joint repair method for trenchless pipe joints, used to repair defects in continuous fiberglass reinforced plastic (FRP) pipes. This method includes: The method includes the following steps: site layout; safety treatment of the pipeline to be repaired; confirmation of the repair area; confirmation of the number of repairs within the repair area; and measurement of the pipeline's internal circumference and crack width. The method further includes: Modular glass-filled sand pipe flexible repair body is prepared according to the length to be repaired, pipe inner diameter, and quantity: The modular glass-filled sand pipe flexible repair body has two mutually staggered spliced ​​B-type superimposed inner expansion ring assemblies, A-type superimposed inner expansion ring unit staggered spliced ​​with the B-type superimposed inner expansion ring, and four stainless steel water-stop ring units. Among them, two stainless steel water-stop rings are distributed on the inner surface of the end of the modular glass-filled sand pipe flexible repair body, and the remaining two stainless steel water-stop rings are distributed at the splicing position of the superimposed inner expansion ring in the modular glass-filled sand pipe flexible repair body. The steps for transporting the modular glass-reinforced flexible repair body to the repair site; The No. 1 rubber ring in the modular glass-reinforced flexible repair body is supported so that the No. 1 rubber ring fits against the pipe wall; Spread the stainless steel water-stop ring along the outer flange opening of the No. 1 rubber ring; The steps for installing the stainless steel ring include: fully opening the stainless steel water-stop ring, ensuring the gap between the ends of the two stainless steel water-stop rings is greater than 20mm, and then installing the hydraulic tool; next, placing the hydraulic tool at the opened end, installing a steel support on the hydraulic tool to support the top of the steel ring, and while the hydraulic tool is pressurized, striking the stainless steel ring with a hammer, ensuring the hammer face is in horizontal contact with the ring surface and the hammer points are evenly distributed on the ring, causing the stainless steel ring to sink into the rubber ring groove; finally, pressurizing to 0.4MPa and continuing to hammer the stainless steel ring until the hydraulic gauge reading of the hydraulic tool no longer drops, and selecting a suitable metal insert to insert into the insert limiting groove according to the opening distance; The groove of the No. 2 rubber ring is overlapped with the protrusion of the No. 1 rubber ring to support it; Install a stainless steel water-stop ring at the overlap of rubber ring 1 and rubber ring 2; Following the same steps, overlap rubber ring #3 with rubber ring #2 and install the remaining two stainless steel water-stop rings. The procedure to confirm the seal at the air valve.

2. The method for repairing trenchless pipe joints using modular pipe quick flexible joints according to claim 1, characterized in that, It also includes a pretreatment step, which includes grinding the pipe and applying a food-grade epoxy resin topcoat to the inner wall surface of the ground glass-reinforced pipe.

3. The method for repairing trenchless pipe joints using modular pipe quick flexible joints according to claim 1, characterized in that, The top of the hydraulic expander of the hydraulic tool (5) is provided with a square metal block fixed seat (8), and the square metal block fixed seat (8) is vertically mounted with a radial support device (9).

4. The method for repairing trenchless pipe joints using modular pipe quick flexible joints according to claim 1, characterized in that, The A-type superimposed inner expansion ring (1) of the A-type superimposed inner expansion ring unit has an A-type superimposed inner expansion ring intermediate body (1a). The two ends of the A-type superimposed inner expansion ring intermediate body are symmetrically distributed with an A-type superimposed inner expansion ring first end (1-1) and an A-type superimposed inner expansion ring second end (1-2). The back of the A-type superimposed inner expansion ring first end (1-1) has a first recessed part (1-1a). The lower surface of the A-type superimposed inner expansion ring first end (1-1) has symmetrical inclined platform protrusions (1-1b). Three inclined platform intermediate protrusions (1-1c) are evenly distributed in the middle of the two inclined platform protrusions (1-1b). There is a U-shaped groove between the two inclined platform intermediate protrusions (1-1c). A C-shaped outer protrusion is provided at the center of the B-type superimposed inner expansion ring intermediate body. The two ends of the B-type superimposed inner expansion ring intermediate body are the first end (2-1) and the second end (2-2) of the B-type superimposed inner expansion ring. The structure of the first end (2-1) of the B-type superimposed inner expansion ring is the same as that of the first end (1-1) of the A-type superimposed inner expansion ring. The second end (2-2) of the B-type superimposed inner expansion ring has a ridge with the same thickness as the B-type superimposed inner expansion ring intermediate body. Three rectangular protrusions (2-2a) are evenly distributed on the surface of the ridge. The spacing between the rectangular protrusions is adapted to the width of the protrusion (1-1c) in the middle of the inclined platform.

5. The method for repairing trenchless pipe joints using modular pipe quick flexible joints according to claim 3, characterized in that, The main body of the radial support device (9) has a threaded first rod-shaped part and a second rod-shaped part that cooperates with the first rod-shaped part and has an internal thread. The first rod-shaped part is vertically provided with a straight rotating rod. The first rod-shaped part is driven to move the first rod-shaped part into the inner cylinder of the second rod-shaped part to realize the length adjustment of the entire main body.

6. A method for repairing trenchless pipe joints using modular, quick-connect flexible joints, characterized in that... It includes the steps of preliminary survey, pre-installation preparation, inner ring installation, rubber ring laying, and pressure testing; In the preliminary survey steps, after the pipeline is shut down, the remaining water in the pipeline is completely drained, an exhaust system is installed, and the air quality in the pipeline is tested using an air quality detector. Once the air quality meets the standards, construction personnel are sent into the pipeline to conduct an on-site survey of the pipeline joints to be repaired, number them, and understand the actual damage to the fiberglass pipeline joints. Each joint and circumferential crack that needs to be repaired is confirmed, and the width and depth of each joint crack are determined. When confirming the pipeline joints that need to be repaired, the condition of the joint, the degree of corrosion, the degree of pollution, solid and loose deposits, wall thickness, etc. are also recorded to provide guidance for the pre-treatment before installation. In the pre-installation preparation steps, before installing the inner expansion ring, the air quality inside the pipeline is first checked with an air detector to ensure it meets the standards, and then construction personnel are sent down into the pipeline to remove the silt inside. In the process of installing the inner expansion ring, before the installation of the inner expansion ring begins, a layer of food-grade epoxy resin paint is applied to the inner wall surface of the pipe after grinding. This paint can play a role in preventing rust and corrosion on the inner wall of the fiberglass pipe. In the step of laying the rubber ring, tighten the bottom air valve with a key, and attach the rubber ring tightly to the joint. Take a 14mm×8mm×2mm steel sheet and place it on the groove at the bottom of the rubber ring. First, install a stainless steel ring with a larger diameter. Place the stainless steel ring roughly in the groove of the rubber ring and gradually open the steel ring until the two ends of the ring bottom are joined together on the pad. Then, use a pry bar to drive wedges into the bottom of the joined stainless steel ring from small to large to facilitate the placement of the hydraulic jack. During installation, first place the hydraulic jack at the port that has been opened by the wedge, and start pressurizing to 0.15 MPa. Use a hammer to lightly tap the stainless steel ring and adjust its position so that it is in the groove of the rubber ring. Install a steel support on the hydraulic jack to support the top of the steel ring. Continue to pressurize to 0.2 MPa, and use a hammer to strike the stainless steel ring forcefully. The hammer surface should be in horizontal contact with the ring surface, and the hammer points should be evenly distributed on the ring so that the stainless steel ring is completely embedded in the groove of the rubber ring. Then, pressurize to 0.4 MPa and continue to hammer the stainless steel ring until the hydraulic gauge reading stops dropping. Since the stainless steel ring has been stretched open, select a suitable stainless steel wedge based on experience to support the load, replacing the previously driven wedge. Finally, release the pressure, disassemble the steel support and hydraulic jack, and use a hammer to hammer the bottom stainless steel wedge to make it fit into the groove, completing the installation. The same method is used for smaller diameter stainless steel rings to form a permanent mechanical seal. Before the pressure test, prepare a miniature air compressor with a portable air canister (10L capacity, 0.8MPa working pressure). Fill the canister with compressed air. During the test, first open the valve on the rubber ring, connect the air outlet of the portable air canister to the valve, and begin inflation. Maintain the working pressure at 0.05MPa. After inflation, begin leak testing. Apply soapy water to both ends of the rubber ring secured by the steel ring and check for continuous, obvious bubbles. If the pressure does not drop, the test is successful. If bubbles appear, reinstall and retest until the test is successful. Finally, release the air and tighten the valve on the rubber ring with a key. The pressure test is now complete.

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