A working device and detection method for pipe jacking machine pipe system test

Abstract

The present disclosure relates to the field of construction machinery testing, and particularly relates to a working device for pipe jacking machine pipeline system testing and a detection method. The working device comprises a circulating water pumping system, a spraying system and a sensor system, which can be pre-arranged on a test base, is simple to operate, convenient and fast, solves the problems of large investment and time-consuming and labor-consuming in actual tunneling and cutting tests, and solves the problem that a large area of site is not necessarily suitable for actual tunneling and cutting tests.

Description

Technical Field

[0001] This disclosure relates to the field of engineering machinery testing, and in particular to a working device and testing method for testing the pipeline system of a pipe jacking machine. Background Technology

[0002] Pipe jacking machines are equipment used in municipal underground trenchless engineering. Their head is a cutterhead used for excavating and cutting rock or soil at the excavation face. A typical pipe jacking machine consists of a cutterhead, front housing, middle housing, rear housing, reduction system, hydraulic system, and electrical system. The cutterhead is used for excavation and cutting. During operation, water is supplied to prevent face collapse and ground subsidence, acting as a pressure balancer. Water mixes with bentonite and other materials to form slurry, creating a dense mud film on the excavation face, preventing water and mud leakage, stabilizing the soil layer, forming a protective membrane, and preventing collapse. The soil and debris cut by the cutterhead mix with water to form a flowable slurry, which is transported to the surface through a slurry discharge pipe for efficient soil removal. The slurry also cools the cutterhead, preventing damage, and reduces resistance between the cutterhead and the soil during cutting, reducing friction and providing lubrication.

[0003] When designing a pipe jacking machine, the water supply system is crucial, especially the angle of the water flow. This ensures the water hits the soil at the correct point, allowing the cutterhead to combine the soil and water to form a flowable slurry that is then transported to the surface via the discharge pipe for efficient soil removal and adequate cooling of the cutterhead. The outlet pressure and flow rate ensure sufficient water supply. However, the pipe jacking machine contains hydraulic and electrical control systems. Water must not enter the connections between the front, middle, and rear housings, as this can cause malfunctions. Furthermore, leaks in the slurry system due to assembly defects or component defects can damage the electrical control box and cause insufficient water supply, thus affecting work efficiency.

[0004] To ensure the smooth operation of the water supply system during pipe jacking machine operation, prevent water leakage at the connections between the casings, and guarantee the safety of the electrical and hydraulic systems, water supply angle, outlet water pressure and flow rate tests must be conducted after product trial production. Leakage tests must also be performed at the casing connections and the mud system. Therefore, designing a working device and testing method for testing the pipe jacking machine's piping system is essential.

[0005] However, the applicant's research revealed that actual testing requires the use of a pipe jacking machine to assess the efficiency and effectiveness of the water supply system. This necessitates a site and the excavation of an end face trench. Each test requires the pipe jacking machine to be lowered into the trench for tunneling and cutting, and a certain distance must be excavated, resulting in the removal of a large amount of soil and subsequent cleanup, thus incurring significant costs. For each new product model of the pipe jacking machine, actual tunneling and cutting tests are required, necessitating the planning of a large testing area, which is also quite challenging in practice. Furthermore, using conventional mud system flushing tests on the pipe jacking machine's mud system, with the entire system flushed at atmospheric pressure, results in slow rise of tiny water bubbles and the absence of bubbles in minute internal seepage, making it undetectable. Additionally, the presence of air within the mud system's internal cavity causes pressure buildup after water injection, with the internal air pressure counteracting the water pressure, hindering seepage through tiny gaps and leading to missed detections. Summary of the Invention

[0006] In view of this, the present disclosure provides a working device and testing method for testing the pipeline system of a pipe jacking machine, which is easy to operate and can meet the testing requirements of the pipeline system of the pipe jacking machine without the need for actual tunneling and cutting tests.

[0007] In one aspect of this disclosure, a working apparatus for testing the piping system of a pipe jacking machine includes: The test base is provided with a water storage tank and a support base for fixing the pipe jacking machine to be tested. The circulating water pumping system has its inlet located in the reservoir. The outlet of the circulating water pumping system is connected to the inlet of the mud system of the pipe jacking machine. The mud system includes multiple parallel mud pipes. Each mud pipe is equipped with an air vent and a pressure sensor. After the mud pipe is vented and the pressure sensor detects and determines that a negative pressure has been formed inside the pipe, the outlet of the circulating water pumping system is connected to the mud pipe to conduct a sealing test of the mud pipe. The spray system includes a frame system located next to the support base and multiple nozzles mounted on the frame system. The multiple nozzles are connected to the second outlet of the circulating water pumping system, and the inlet of the circulating water pumping system is connected in parallel with the first and second outlets. The multiple nozzles are arranged circumferentially relative to the pipe jacking machine under test and are used to spray water toward the pipe jacking machine to detect the sealing performance of the shell connection of the pipe jacking machine. The nozzles need to be kept closed when the mud pipe is being tested for sealing performance. The sensor system includes a pressure sensor and a flow sensor located at the outlet of the pipe jacking machine.

[0008] Optionally, the circulating water pumping system includes: A rigid pipe, the opening of which extends into the water storage tank, serves as the inlet of the circulating water pumping system. The water pump is connected to the water pump inlet elbow via a connecting pipe. The water pump outlet is connected to a flange welded head. The outlet one, outlet two, and outlet three of the flange welded head are respectively connected to the inlet ends of the sprinkler system, the manual sprinkler pipe, and the mud system.

[0009] Optionally, the outlet of the flange welded joint is connected to a safety valve.

[0010] Optionally, the rack system includes: The main frame includes oppositely arranged uprights and welded crossbeams located between the uprights; Multiple stainless steel rigid pipe welded components are sequentially connected to the inner side of the frame body to form an arc-shaped spray pipeline, and the multiple nozzles are all located on the arc-shaped spray pipeline.

[0011] Optionally, the bottom of the stand is provided with pulleys, which can be used to adjust the position of the frame system.

[0012] Optionally, the support base includes: Beam base, The diagonal bracing welded components are installed on both sides of the crossbeam base through mounting holes, and the end faces of the diagonal bracing welded components on both sides facing each other form a support plane; the pipe jacking machine to be tested is placed on the support plane of the crossbeam base and the diagonal bracing welded components on both sides.

[0013] Optionally, the crossbeam base is provided with multiple sets of mounting holes. By adjusting the position of the mounting holes for the inclined brace welded parts, the distance between the inclined brace welded parts on both sides can be adjusted to suit pipe jacking machines of various sizes.

[0014] Optionally, the mud system includes: A reducing connector is connected to the outlet end of the circulating water pumping system, and the reducing connector is connected in parallel with multiple mud pipes.

[0015] Optionally, it also includes: A protective net is installed above the water storage tank.

[0016] Secondly, the present invention provides a testing method for a pipe jacking machine pipeline system, which is based on the aforementioned working device for testing a pipe jacking machine pipeline system, the testing method comprising: When it is necessary to test the sealing of the mud pipe of the pipe jacking machine, the vent is connected to an external air source. After the pressure sensor detects that a negative pressure has formed in the mud pipe, the outlet of the circulating water pumping system is connected to the mud pipe to inject water into the mud pipe. When the pressure sensor detects that the pressure has reached the preset low pressure value, the pressure is maintained for a preset time to conduct a low-pressure leakage test. Then the pressure is increased. When the pressure sensor detects that the pressure has reached the preset medium pressure value, the pressure is maintained for a preset time to conduct a medium-pressure leakage test. When it is necessary to detect leakage at the shell connection of the pipe jacking machine, move the frame system to the outside of the pipe jacking machine to be tested and make multiple nozzles face the shell connection position of the pipe jacking machine. Then, connect the two nozzles at the outlet of the circulating water pump system to carry out the spray test. During the spraying process, check whether there is leakage between two adjacent shell sections. When it is necessary to perform overflow detection on the water pump of the pipe jacking machine, control the output pressure of the water pump to rise to a preset safety threshold to detect whether the safety valve is working properly. When it is necessary to test the pressure and flow rate of the outlet of the pipe jacking machine, the outlet of the pipe jacking machine is opened to flush the cutterhead. The pressure sensor and flow sensor are used to detect the pressure and flow rate of the outlet to determine whether the outlet can meet the flushing requirements of the cutterhead.

[0017] Compared with existing technologies, the present invention has the following advantages: 1. The working device of the present invention includes a circulating water pumping system, a spraying system and a sensor system, all of which can be pre-arranged on the test foundation. The operation is simple, convenient and quick, which solves the problems of large investment and labor and time cost in actual tunneling and cutting tests, and also solves the problem that the site area is large and indoor spaces may not be suitable for actual tunneling and cutting tests.

[0018] 2. When the sealing of the slurry pipeline of the pipe jacking machine needs to be tested, the present invention connects the vent to an external air source. After the pressure sensor detects that a negative pressure has formed inside the slurry pipeline, the outlet of the circulating water pumping system is connected to the slurry pipeline to inject water into the slurry pipeline. When the pressure sensor detects that the pressure has reached a preset low pressure value, the pressure is maintained for a preset time to conduct a low-pressure leakage test. Subsequently, the pressure is increased. When the pressure sensor detects that the pressure has reached a preset medium pressure value, the pressure is maintained for a preset time to conduct a medium-pressure leakage test. The present invention can pre-extract the air inside the slurry pipeline by using the vent in conjunction with the air circuit system, forming a negative pressure inside the pipeline. The water pressure uses preset low and medium pressure values, and both need to be maintained for 10 minutes for testing, and the leakage at each connection point of the pipeline is observed. This invention is divided into low-pressure holding and medium-pressure stabilization. Water is injected independently into each sealed water passage segment by segment, allowing for zoned immersion. Because a significant pressure is created throughout the entire water passage, water can fully penetrate the interior. Minor leaks are slow and form continuous watermarks, eliminating the need to wait for air bubbles. Micrometer-level leaks can be identified. Segmented testing accurately pinpoints leak points, significantly improving the detection rate of micro-leaks. This solves the problem of simply using atmospheric pressure immersion, where tiny leaks and air bubbles rise slowly, and minor internal leaks go undetected due to the lack of air bubbles. Simultaneously, an air system is used to extract air from the pipes, creating negative pressure inside the cavity. This eliminates air resistance within the cavity, ensuring that water pressure acts fully on the sealing surface, allowing hidden leaks to drain smoothly. This reduces the risk of missed leaks caused by air trapped inside the water passage after water injection, where internal air pressure counteracts water pressure, hindering seepage through tiny gaps.

[0019] 3. When leakage detection is required at the shell connection of the pipe jacking machine, the present invention moves the frame system to the outside of the pipe jacking machine to be tested, and aligns multiple nozzles with the shell connection position of the pipe jacking machine. Then, the outlet of the circulating water pump system is connected to the nozzles for spray testing. During the spraying process, leakage is detected between adjacent shell sections. The present invention uses multi-directional spray testing for leakage detection, providing a more comprehensive detection range. When overflow detection is required for the pipe jacking machine's water pump, the pump's output pressure is controlled to rise to a preset safety threshold to check if the safety valve is functioning properly, thereby ensuring the safe operation of the pipe jacking machine. When pressure and flow detection is required for the pipe jacking machine's outlet, the outlet is opened to flush the cutterhead. Pressure sensor two and flow sensor two are used to detect the pressure and flow at the outlet to determine if the outlet can meet the flushing requirements of the cutterhead. Attached Figure Description

[0020] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.

[0021] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein: Figure 1 This is a schematic diagram of a working device and testing method for testing the pipeline system of a pipe jacking machine according to some embodiments of the present disclosure; Figure 2 This is a schematic diagram of a circulating water pumping system for testing a pipe jacking machine pipeline system according to some embodiments of the present disclosure; Figure 3 This is a schematic diagram of a circulating water pump for testing a pipe jacking machine pipeline system according to some embodiments of the present disclosure; Figure 4 This is a schematic diagram of a support base for a working device and testing method for testing a pipe jacking machine pipeline system, according to some embodiments of this disclosure; Figure 5 This is a schematic diagram of a ground anchor system spraying system for a working device and testing method for testing a pipe jacking machine pipeline system, according to some embodiments of the present disclosure. Figure 6 This is a schematic diagram of a frame system for a working device and testing method for testing a pipe jacking machine pipeline system according to some embodiments of the present disclosure; Figure 7 This is a schematic diagram of water outlet and slurry inlet at the end face of a pipe jacking machine, which is a working device and testing method for testing the pipeline system of a pipe jacking machine according to some embodiments of the present disclosure. Figure 8This is a schematic diagram of a mud system for a working device and testing method for testing a pipe jacking machine pipeline system according to some embodiments of the present disclosure; Figure 9 This is a schematic diagram of an automatic float valve for a working device and testing method for testing a pipe jacking machine pipeline system, according to some embodiments of the present disclosure; In the picture: 1. Circulating water pumping system; 2. Support base; 3. Sprinkler system; 4. Pipe jacking machine; 5. Protective net; 6. Test foundation; 7. Electrical control system; 101. Circulating water pump; 102. Hope 1; 103. Hope 3; 104. Hope 2; 105. Connecting pipe; 106. Elbow; 107. Pipe clamp; 108. Reducer; 109. Rigid pipe; 110. Safety valve; 1011. Water pump; 1012. Bolt 1; 1013. Nut 1; 1014. Flange welded joint; 1015. Valve 2; 1016. Flange welded joint; 1017. Valve 1; 1018. Inlet elbow; 1019. Outlet elbow; 201. Diagonal brace welded component; 202. Crossbeam base; 203. Bolt 2; 204. Nut 2; 301. Frame system; 302. Stainless steel rigid pipe welded component 1; 303. Bolt 3; 304. Washer 1; 305. Clamp; 306. Bolt 4; 307. Nut 3; 308. Washer 2; 309. Stainless steel rigid pipe welded component 2; 310. Stainless steel joint; 311. Stainless steel elbow; 312. Nozzle; 313. Stainless steel rigid pipe welded component 3; 314. Stainless steel straight pipe; 3011. Pulley; 3012. Bolt 5; 3013. Nut 4; 3014. Stand; 3015. Bolt 6; 3016. Nut 5; 3017, Washer 3; 3018, Welded crossbeam; 3019, Diagonal brace; 401, Water outlet; 402, Slurry inlet; 403, Connection between shells; 404, Water inlet pipe 1; 405, Automatic float valve; 406, Water pipe 1; 407, Water pipe 2; 408, Water pipe 3; 409, Blocking plate; 410, Vent; 411, Water pipe 4; 412, Water pipe 5; 413, Manual ball valve; 414, Water inlet pipe 2; 415, Pressure sensor 1. Detailed Implementation

[0022] The applicant's research found that: To ensure the smooth operation of the water supply system during pipe jacking machine operation, prevent water leakage at the connection between the shells, and ensure the safety of the electrical and hydraulic systems, water supply angle, outlet water pressure and flow rate tests must be conducted after product trial production. At the same time, water leakage tests at the shell connection points must also be conducted.

[0023] Combination Figure 1 and Figure 2This embodiment provides a working device for testing the pipeline system of a pipe jacking machine, which includes a test base 6, a circulating water pumping system 1, and a spraying system 3. A water storage tank is provided on the test base 6, and a support base 2 for fixing the pipe jacking machine 4 to be tested is also provided on the test base 6. The water inlet of the circulating water pumping system 1 is located in the water storage tank, and the water outlet of the circulating water pumping system 1 is connected to the water inlet of the mud system of the pipe jacking machine 4. The mud system includes multiple parallel mud pipes. The mud pipes are provided with vents 410 and pressure sensors 415. After the mud pipes are evacuated through the vents 410 and the pressure sensors 415 detect and determine that a negative pressure has been formed in the pipes, the water outlet of the circulating water pumping system 1 is connected to the mud pipes to conduct a sealing test of the mud pipes.

[0024] The spray system 3 includes a frame system located next to the support base 2 and multiple nozzles 312 mounted on the frame system. The multiple nozzles 312 are connected to the second outlet of the circulating water pumping system 1. The inlet of the circulating water pumping system 1 is connected in parallel with the first and second outlets. The multiple nozzles 312 are arranged circumferentially relative to the pipe jacking machine 4 to be tested. The multiple nozzles 312 are used to spray water toward the pipe jacking machine 4 to test the sealing performance of the shell connection of the pipe jacking machine 4. The nozzles need to be kept closed when the mud pipe is tested for sealing performance.

[0025] Specifically, water needs to be pre-filled in the test foundation 6, and the rigid pipe 109 in the circulating water pumping system 1 is placed into the pit of the test foundation 6. The reducing joint 108 and pipe clamp 107 in the circulating water pumping system 1 are connected to the water system in the pipe jacking machine 4 to test whether the design of the pipe system of the pipe jacking machine 4 meets the requirements.

[0026] In this embodiment, the pipe jacking machine 4 is placed on the support base 2 to support the pipeline system testing of the pipe jacking machine 4. The spray system 3 is placed around the pipe jacking machine 4, with the nozzles 312 of the spray system 3 aligned with the connection points of adjacent shell sections of the pipe jacking machine 4 to detect whether the adjacent shell sections leak. Because the water storage tank of the test foundation 6 has a certain depth, a protective net 5 is placed above the water storage tank to ensure safety. The hose 102 is connected to the circulating water pump 101 and its matching outlet, and then the hose 102 is connected to the stainless steel rigid pipe welded joint 313 in the spray system 3 to supply water to the nozzles. The rigid pipe 109 is connected to the elbow 106 via the pipe clamp 107, and then connected to the inlet elbow 1018 of the circulating pump 1 via the connecting pipe 105; the flexible hose 103 is connected to the outlet elbow 1019 of the circulating pump 1, and the other end of the flexible hose 103 is connected to the elbow 106 of the mud pipe entering the pipe jacking machine 1, and then connected to the reducer 108 via the pipe 107. The reducer 108 is connected to the mud system of the pipe jacking machine 1 via the pipe clamp.

[0027] Combination Figure 3 At the fourth largest diameter of the flange welded joint 1016 in the circulating water pump 101, a safety valve 110 is connected via a thread. Because different models of pipe jacking machines 4 have different pipe diameters in their mud systems, different diameter reducers 108 are used to meet the testing requirements of the mud systems for different models of pipe jacking machines 4. The flange welded joint 1014 is connected to the inlet of the water pump 1011 via bolts 1012 and nuts 1013. The other end of the flange welded joint 1014 is connected to the inlet elbow 1018 via a pipe clamp 107. The inlet elbow 1018 is connected to the hose 103 via the pipe clamp 107. The flange welded joint 1016 is connected to the outlet of the water pump 1011 via bolts 1012 and nuts 1013. The largest diameter of the flange welded joint 1016... The large outlet is connected to the outlet elbow 1019 via bolt 1012 and nut 1013. The outlet elbow 1019 is connected to the hose 103 via pipe clamp 107. Valve 1017 is connected to the second largest diameter of the flange welded joint 1016. Valve 1017 is connected to hose 102. Valve 2 1015 is connected to the third largest diameter of the flange welded joint 1016. Valve 2 1015 is connected to hose 2 104.

[0028] Combination Figure 4 In this embodiment, the support base 2 includes a crossbeam base 202 and diagonal bracing welded parts installed on both sides of the crossbeam base 202. Two diagonal bracing welded parts 201 are connected to the crossbeam base 202 by bolts 203 and nuts 204. Eight sets of holes are provided on the top of the crossbeam base 202. By adjusting the position of the holes, the distance between the diagonal bracing welded parts 201 can be adjusted to meet the support function of different models of pipe jacking machines 4.

[0029] Cut Figure 5 and Figure 6In the circulating water pumping system 1, one end of the hose 104 is connected to the nozzle 312 for manual spraying, which satisfies the situation where some pipe jacking machines cannot be sprayed when the spraying system 3 sprays the connection 403 between the casings of the pipe jacking machine 4. The above constitutes the circulating water pump 101. In this embodiment, stainless steel rigid pipe welded component 302 is connected to stainless steel rigid pipe welded component 309 via bolt 306, nut 307, and washer 308, and then connected to stainless steel rigid pipe welded component 313 via bolt 306, nut 307, and washer 308. The connecting bodies of stainless steel rigid pipe welded component 302, stainless steel rigid pipe welded component 309, and stainless steel rigid pipe welded component 313 are then connected to the frame system 301 via bolt 303, washer 304, and clamp 305. In this embodiment, stainless steel connectors 310 are connected to the corresponding interfaces of stainless steel rigid pipe welded component 302, stainless steel rigid pipe welded component 309, and stainless steel rigid pipe welded component 313, totaling 13 connectors. After connecting stainless steel straight pipe 314 to stainless steel connector 310, stainless steel elbow 311 is connected to stainless steel straight pipe 314, and nozzle 312 is connected to stainless steel elbow 311, totaling 13 connectors.

[0030] Because the diameter of the pipe jacking machine 4 varies greatly, ranging from 600mm to 4800mm, one type of spray system 3 may not be able to meet the spray test requirements of all models of pipe jacking machines. Therefore, according to the different diameters of the pipe jacking machine 4, two types of spray systems 3 can be divided into two types with different sizes but the same function.

[0031] The pipe jacking machine 4 comes in various models with different diameters. The stainless steel straight pipe 314 can be made in several different lengths to meet the spray test requirements of different models of the pipe jacking machine 4. Because the stainless steel straight pipe 314 is frequently replaced depending on the model of the pipe jacking machine 4, the threads of the stainless steel connector 310 connected to it may be damaged; therefore, the stainless steel connector 310 is defined as a vulnerable part. The pulley 3011 is connected to the upright frame 3014 via bolt 3012 and nut 3013. Then, the crossbeam welded component 3018 is connected to the two upright frames 3014 via bolt 3015, nut 3016, and washer 3017. Finally, the diagonal brace 3019 is connected to the crossbeam welded component 3018 and the upright frame 3014 via bolt 3015, nut 3016, and washer 3017, forming the frame system 301.

[0032] The electrical control system 7 in this embodiment consists of an operating console, a control cabinet, and cables. The control cabinet uses a frequency converter to control the motor speed of the water pump 1011, thereby controlling the discharge capacity of the water pump 1011. Since the discharge capacity of the mud system varies depending on the model of the pipe jacking machine 4, the discharge capacity of the mud system of different models of pipe jacking machines 4 is controlled by controlling the discharge capacity of the water pump 1011.

[0033] Combination Figure 8and Figure 9 In this embodiment, the mud system of the pipe jacking machine 4 consists of five water channels. The reducing connector 108 of the pipe jacking machine 4 is used to connect to the first water inlet pipe 404, which has four outlets. The first outlet is connected to an automatic float valve 405, then to a water pipe 406, and then to a plug plate 409. The second outlet is connected to an automatic float valve 405, then to a water pipe 407, and then to a manual ball valve 413. The third outlet is connected to an automatic float valve 405. Ball valve 405 is connected to water pipe 3 408, then to manual ball valve 413. The fourth outlet is connected to automatic float valve 405, then to inlet pipe 2 414. Inlet pipe 2 414 has two outlets. The first outlet is connected to automatic float valve 405, then to water pipe 411, then to manual ball valve 413. The second outlet is connected to automatic float valve 405, then to water pipe 5 412, then to manual ball valve 413. Air inlets 410 are installed above water pipes 1 406, 2 407, 3 408, 4 411, and 5 412. Through the air circuit system, air is drawn out of each water pipe, creating negative pressure inside each water pipe. Pressure sensors 415 are installed above water pipes 1 406, 2 407, 3 408, 4 411, and 5 412 to detect the pressure of each water circuit. The automatic float valve 405 consists of a hydraulic cylinder 4051, a switching structure 4052, and a float valve 4053.

[0034] The testing process for the mud system pipeline of the pipe jacking machine 4 includes: the circulating water pump system 1 pumps water from the reservoir in the test foundation 6 through the rigid pipe 109, and the water enters the mud system inlet pipe 404 of the pipe jacking machine 4 through the reducer 108. When testing the sealing performance of the mud system, the sealing performance of each water circuit is tested separately. After the manual ball valve 413 of each water circuit is closed, the automatic float valve 405 of each circuit is then closed through the electrical control system. When testing the first water circuit, the air circuit system is connected through the vent 410 to the second water circuit. Air is removed from the first water circuit, creating a negative pressure of -2 kg. The circulating water pump system 1 is then activated, and the water flow is controlled to allow water to enter the first water circuit of the mud system at a relatively low flow rate. On the control screen, the pressure sensor 415 is set to 2 kg via the electronic control system and held for 10 minutes. Leakage at each connection point is observed. The pressure sensor 415 is then set to 4 kg and held for 10 minutes, with leakage observed again. For the second, third, fourth, and fifth water circuits, each circuit is tested individually via the automatic float valve 405. Air is removed from the pipes via the air system, creating a negative pressure of 2 kg. The water pressure is set to low pressure (2 kg) and medium pressure (4 kg), held for 10 minutes at each pressure, and leakage at each connection point is observed.

[0035] Water is injected separately into the water system, with low-pressure maintenance and medium-pressure stabilization. Water is injected independently into each sealed section of the water system, allowing for zoned immersion. Because a significant pressure is created throughout the entire water system, water can fully penetrate the interior. Minor leaks are slow and form continuous watermarks, eliminating the need to wait for air bubbles. Micrometer-level leaks can be identified. Segmented testing precisely pinpoints leak points, significantly improving the detection rate of micro-leaks. This solves the problem of simply using atmospheric pressure immersion, where tiny leaks and air bubbles rise slowly, or where minor internal leaks go undetected due to the lack of air bubbles. Simultaneously, an air system is used to remove air from the pipes, creating negative pressure and eliminating air resistance within the cavity. Water pressure is then fully applied to the sealing surface, allowing hidden leaks to drain smoothly. This reduces the risk of missed leaks caused by air trapped in the water system cavity after injection, where internal air pressure counteracts water pressure, hindering seepage through tiny gaps.

[0036] In this embodiment, the front of the pipe jacking machine 4 is equipped with 4 sets of 8 water outlets 401 and several grout inlets 402. The water outlets 401 and grout inlets 402 vary depending on the model of the pipe jacking machine 4. The angle of the water outlets 401 on the end face of the front housing of the pipe jacking machine 4 is designed differently to ensure that water can be sprayed onto the cutterhead of the pipe jacking machine during construction, flushing away the frictional resistance caused by the mud on the cutterhead, and spraying water onto the mud flow at the grout inlet 402 to dilute the mud flow, prevent blockage of the grout inlet 402, and reduce the heat of the cutterhead during operation. Therefore, the water pressure, flow rate, and flow velocity at the water outlets 401 are critical parameters. The pipe jacking machine 4 is generally divided into three housing sections: a front housing, a middle housing, and a rear housing. During operation, water must not enter the connection points 403 between each housing section; therefore, the sealing performance of the connection points 403 between the housing sections needs to be checked.

[0037] The slurry system pipeline of the pipe jacking machine 4 is tested. According to the model of the pipe jacking machine 4 and the parameters of the slurry system of the pipe jacking machine of that model, the frequency converter is adjusted through the control cabinet of the electrical control system 7 to control the flow and pressure of the water pump 1011. When the pressure of the water pump 1011 exceeds the set value, the safety valve 110 overflow threshold is triggered to ensure that the test system is carried out normally. The circulating water pump system 1 pumps water from the water storage tank in the test foundation 6 through the rigid pipe 109 and enters the mud system of the pipe jacking machine 4 through the reducing joint 108. Valve 1017 and valve 21015 are in a closed state, that is, the spray test is in a closed state.

[0038] Install flow sensors at outlets 401, one flow sensor at each outlet 401, and measure the flow rate at each outlet 401; According to the formula: Q=V×A Note: Q: Volumetric flow rate (m³ / s) V: Average velocity (m / s) A: Cross-sectional area of ​​the flow path in m², corresponding to a circular pipe, A = Π × D / 2², where D is the pipe diameter.

[0039] In this experiment, Q represents the flow rate measured by the flow meter, and A represents the pipe cross-sectional area. Therefore, the velocity V = Q / A can be calculated. According to the formula: V = √V0 + gt² Calculate the V0 value, and then, based on tanα=gt / 2 V0, select t=1s to calculate the initial angle. Compare this with the design angle of the outlet 401 to determine the conformity between the design and the actual measurement.

[0040] Then, according to the formula: y=g / 2V0²*x, plot the trajectory of the water drop point at each outlet 401, and determine whether the water drop point meets the design requirements.

[0041] Install pressure sensors at outlet 401 to detect the pressure at each outlet 401, ensuring the pressure and flow rate at each outlet 401, and determine whether the water flow rate and pressure meet the design requirements when the pipe jacking machine cutterhead is working.

[0042] For the sealing test of the connection 403 between the housings of the pipe jacking machine 4, the spray system 3 is moved to the connection 403 between the housings of the pipe jacking machine 4 so that the nozzles 312 of the spray system 3 are aligned with the connection 403 between the housings. Open valve 1017 in circulating water pump system 1 and close other outlet valves of flange weld joint 1016. Water then enters hose 102 through valve 1017 in circulating water pump system 1, and then enters spray system 3. Through nozzles 312 of spray system 3, water is sprayed onto the connection 403 between the shells of pipe jacking machine 4. There are 13 nozzles 312, evenly spraying water onto the connection 403 between the shells. As an example, visual inspection can be used to check for leaks at the connection 403 between the shells of pipe jacking machine 4. This method is intuitive and easy to operate. Alternatively, ultrasonic testing can be used. An ultrasonic instrument is moved along the connection 403 between the shells; the point with the strongest signal is a suspected leak point. Visual inspection can then be used to determine if a leak has occurred. The following description, in conjunction with the accompanying drawings, further illustrates this application: 1. A nozzle 312 is connected to one end of the hose 104 in the circulating water pumping system 1 for manual spraying, which addresses the situation where some pipe jacking machines cannot be sprayed when the spraying system 3 sprays the connection 403 between the casings of the pipe jacking machine 4.

[0043] 2. Because the diameter of the pipe jacking machine varies greatly, from 600mm to 4800mm, one spray system 3 may not be able to meet the spray test requirements of all models of pipe jacking machines. Therefore, two spray systems 3 can be divided according to the different diameters of the pipe jacking machines. They have different sizes but the same function.

[0044] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A working device for testing the pipeline system of a pipe jacking machine, characterized in that, include: The test base is provided with a water storage tank and a support base for fixing the pipe jacking machine to be tested. The circulating water pumping system has its inlet located in the reservoir. The outlet of the circulating water pumping system is connected to the inlet of the mud system of the pipe jacking machine. The mud system includes multiple parallel mud pipes. Each mud pipe is equipped with an air vent and a pressure sensor. After the mud pipe is vented and the pressure sensor detects and determines that a negative pressure has been formed inside the pipe, the outlet of the circulating water pumping system is connected to the mud pipe to conduct a sealing test of the mud pipe. The spray system includes a frame system located next to the support base and multiple nozzles mounted on the frame system. The multiple nozzles are connected to the second outlet of the circulating water pumping system, and the inlet of the circulating water pumping system is connected in parallel with the first and second outlets. The multiple nozzles are arranged circumferentially relative to the pipe jacking machine under test and are used to spray water toward the pipe jacking machine to detect the sealing performance of the shell connection of the pipe jacking machine. The nozzles need to be kept closed when the mud pipe is being tested for sealing performance. The sensor system includes a pressure sensor and a flow sensor located at the outlet of the pipe jacking machine.

2. The working device for testing the pipeline system of a pipe jacking machine according to claim 1, characterized in that, The circulating water pumping system includes: A rigid pipe, the opening of which extends into the water storage tank, serves as the inlet of the circulating water pumping system. The water pump is connected to the water pump inlet elbow via a connecting pipe. The water pump outlet is connected to a flange welded head. The outlet one, outlet two, and outlet three of the flange welded head are respectively connected to the inlet ends of the sprinkler system, the manual sprinkler pipe, and the mud system.

3. The working device for testing the pipeline system of a pipe jacking machine according to claim 2, characterized in that, The outlet of the flange welded joint is connected to a safety valve.

4. The working device for testing the pipeline system of a pipe jacking machine according to claim 1, characterized in that, The rack system includes: The main frame includes oppositely arranged uprights and welded crossbeams located between the uprights; Multiple stainless steel rigid pipe welded components are sequentially connected to the inner side of the frame body to form an arc-shaped spray pipeline, and the multiple nozzles are all located on the arc-shaped spray pipeline.

5. A working device for testing the pipeline system of a pipe jacking machine according to claim 4, characterized in that, The bottom of the stand is equipped with pulleys, which can be used to adjust the position of the frame system.

6. A working device for testing the pipeline system of a pipe jacking machine according to claim 1, characterized in that, The support base includes: Beam base, The diagonal bracing welded components are installed on both sides of the crossbeam base through mounting holes, and the end faces of the diagonal bracing welded components on both sides facing each other form a support plane; the pipe jacking machine to be tested is placed on the support plane of the crossbeam base and the diagonal bracing welded components on both sides.

7. A working device for testing the pipeline system of a pipe jacking machine according to claim 6, characterized in that, The crossbeam base is provided with multiple sets of mounting holes. By adjusting the position of the mounting holes for the inclined brace welded parts, the distance between the inclined brace welded parts on both sides can be adjusted to suit pipe jacking machines of various sizes.

8. A working device for testing the pipeline system of a pipe jacking machine according to claim 1, characterized in that, The mud system includes: A reducing connector is connected to the outlet end of the circulating water pumping system, and the reducing connector is connected in parallel with multiple mud pipes.

9. A working device for testing the pipeline system of a pipe jacking machine according to claim 1, characterized in that, Also includes: A protective net is installed above the water storage tank.

10. A testing method for a pipe jacking machine piping system, characterized in that, The testing is performed using the working apparatus for testing the pipeline system of a pipe jacking machine as described in any one of claims 1-9, and the testing method includes: When it is necessary to test the sealing of the mud pipe of the pipe jacking machine, the vent is connected to an external air source. After the pressure sensor detects that a negative pressure has formed in the mud pipe, the outlet of the circulating water pumping system is connected to the mud pipe to inject water into the mud pipe. When the pressure sensor detects that the pressure has reached the preset low pressure value, the pressure is maintained for a preset time to conduct a low-pressure leakage test. Then the pressure is increased. When the pressure sensor detects that the pressure has reached the preset medium pressure value, the pressure is maintained for a preset time to conduct a medium-pressure leakage test. When it is necessary to detect leakage at the shell connection of the pipe jacking machine, move the frame system to the outside of the pipe jacking machine to be tested and make multiple nozzles face the shell connection position of the pipe jacking machine. Then, connect the two nozzles at the outlet of the circulating water pump system to carry out the spray test. During the spraying process, check whether there is leakage between two adjacent shell sections. When it is necessary to perform overflow detection on the water pump of the pipe jacking machine, control the output pressure of the water pump to rise to a preset safety threshold to detect whether the safety valve is working properly. When it is necessary to test the pressure and flow rate of the outlet of the pipe jacking machine, the outlet of the pipe jacking machine is opened to flush the cutterhead. The pressure sensor and flow sensor are used to detect the pressure and flow rate of the outlet to determine whether the outlet can meet the flushing requirements of the cutterhead.

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