Pipe dynamic pressure testing and pipe flushing integrated device and method based on water hammer effect

Abstract

The invention provides a pipe dynamic pressure testing and pipe flushing integrated device and method based on a water hammer effect. The device comprises a motor (1), a pump body (2), a reversing valve (3), a steel pipe (4) to be subjected to pressure measurement, a clamp (5), a safety valve (6), an on-off valve (7), a one-way valve (8), an overflow valve (9), a cavity (10), an air spring (11) and a steel pipe (12) to be washed. The invention further relates to a method of the pipe dynamic pressure testing and pipe flushing integrated device based on the water hammer effect. The steel pipe (4) to be subjected to pressure measurement and the steel pipe (12) to be washed are linked through the reversing valve (3), seamless switching between water hammer testing and high-pressure washing is achieved, dual operation can be completed without pipeline disassembly and assembly, and the problem that traditional split type equipment is tedious in operation is solved.

Description

Technical Field

[0001] This invention belongs to the field of pipe pressure testing technology; in particular, it relates to an integrated device and method for dynamic pressure testing and flushing of pipes based on the water hammer effect. Background Technology

[0002] In the petroleum, chemical, and municipal water supply industries, pipes serve as the core carriers for fluid transportation. Their dynamic load performance in withstanding instantaneous pressure shocks and the cleanliness of the pipeline directly determine the system's operational safety and service life. In actual working conditions, pipes often face sudden situations such as valve closure and pump shutdown, causing the high-speed fluid inside the pipe to momentarily stagnate. Based on the water hammer effect, transient high pressure far exceeding the static pressure is generated. If the dynamic load performance of the pipe does not meet the standards, it can easily lead to safety accidents such as pipeline rupture and fluid leakage. It is essential to clean the pipes first to remove residual pipe debris, scale, and other impurities. If these are not cleaned in time, they will block the flow channels, accelerate equipment wear, and affect subsequent testing and use.

[0003] Firstly, there is the split-type solution of "static water pressure test + independent cleaning equipment". In this type of solution, the static water pressure test gradually increases the pressure inside the pipe by pumping and maintains the pressure. It can only verify the long-term pressure resistance of the pipe under stable pressure. It cannot simulate the transient high pressure generated by water hammer effect. The test results are seriously out of touch with the actual working conditions. Although some pipes pass the static test, they will still experience dynamic failure problems such as pipe wall cracking and weld leakage when they are actually subjected to water hammer, which poses a safety hazard to the subsequent operation of the system.

[0004] Secondly, there are single-function solutions for simple water hammer testing devices. Some technologies attempt to construct water hammer testing devices using a "pump body + quick-closing valve." While this can generate transient high pressure, it suffers from three key drawbacks: First, it lacks a pressure buffer structure. The instantaneous high pressure generated by water hammer directly acts on valves, pipelines, and other components, easily leading to deformation of the quick-closing valve core, loosening of pipeline interfaces, high equipment failure rate, and short service life. Second, the safety protection mechanism is incomplete, relying solely on a single overflow valve for pressure relief. If the overflow valve's response is delayed or blocked, the overpressured fluid cannot be discharged in time, easily causing pipeline rupture, posing risks to equipment damage and personnel safety. Third, it lacks integrated cleaning functionality. Cleaning the pipeline requires repeated disassembly and cleaning before testing; this method cannot achieve integrated "testing-cleaning" operations, contradicting the current development needs for integrated and efficient industrial equipment. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated device and method for dynamic pressure testing and flushing of pipes based on the water hammer effect.

[0006] This invention is achieved through the following technical solution:

[0007] This invention relates to an integrated device for dynamic pressure testing and flushing of pipes based on the water hammer effect, comprising: a motor 1, a pump body 2, a reversing valve 3, a steel pipe to be tested 4, a clamp 5, a safety valve 6, an on / off valve 7, a check valve 8, an overflow valve 9, a chamber 10, an air spring 11, and a steel pipe to be flushed 12.

[0008] Motor 1 is connected to pump body 2. One side of pump body 2 is connected to water tank or oil tank, and the other side is connected to directional valve 3 through flange; this ensures that the fluid does not leak during transportation.

[0009] The reversing valve 3 has two valve outlets; the straight-through valve port is connected to the steel pipe 4 to be tested through a flange and is fixed by a clamp 5.

[0010] The end of the steel pipe 4 to be tested is connected to a short pipe equipped with a safety valve 6 and an on / off valve 7;

[0011] Another valve port of the reversing valve 3 is connected to the pipeline via a flange. The pipeline is equipped with a check valve 8 and an overflow valve 9. The other side of the pipeline is connected to the accumulator via a flange. An air spring 11 is installed in the left half of the accumulator to better stabilize the system pressure. The outlet of the accumulator is connected to the steel pipe 12 to be flushed and is fixed by two clamps 5.

[0012] Preferably, the motor 1 is cylindrical or square with a shell, and has a fixed bracket at the bottom. One end is connected to an external clean water source, and the other end is connected to the reversing valve 3 through a flange. It can pressurize low-pressure water into high-pressure fluid, providing core power for water pressure testing and pipeline cleaning, and the output pressure can be adjusted by preset parameters.

[0013] Preferably, the reversing valve 3 is provided with multiple interfaces; wherein the first interface is connected to the water inlet of the motor 1, the second interface is connected to the chamber 10, and the third interface is connected to the steel pipe 4 to be tested.

[0014] Preferably, the one-way valve 8 has a "valve core + spring" structure; it only allows fluid to flow unidirectionally from the motor 1 side to the second pipeline, and is initially closed due to insufficient pressure.

[0015] Preferably, the overflow valve 9 is connected in parallel with the main system passage and has a pressure relief outlet. It can automatically open to relieve pressure when the system pressure exceeds the safety threshold, and the two work together to achieve fluid passage switching and system pressure protection.

[0016] Preferably, the accumulator is a constant-pressure structure, capable of absorbing pressure shocks caused by water hammer and protecting system components; it can also stabilize system pressure by compressing or expanding the air chamber during pressure fluctuations; when the system requires a large flow rate for a short period, it can release the stored liquid as an auxiliary power source; and it can store liquid when the system flow rate demand is low and release liquid when it is high, reducing pump energy consumption and achieving energy saving. It is installed between the side port of the reversing valve 3 and the steel pipe 12 to be flushed, used to buffer fluid pressure, reduce fluctuations, and stabilize the flow rate.

[0017] The second cleaning pipeline of the present invention is connected at one end to the side port of the reversing valve 3 and at the other end to the drain or wastewater collection device. The inner diameter of the pipeline is designed according to the size of the impurities to be cleaned. It can receive the high-pressure fluid after the one-way valve is turned on, and use the flushing force of the high-speed fluid to peel off the impurities on the inner wall and discharge them, thereby realizing the pipeline cleaning function.

[0018] This invention also relates to a method for an integrated device for dynamic pressure testing and flushing of pipes based on the water hammer effect, comprising the following steps:

[0019] After turning on the motor 1 switch and starting the pump body 2, the low-pressure water source is pressurized to the preset initial pressure, and the fluid at this pressure is stably delivered to the inlet of the reversing valve 3. At this time, the pressure has not reached the opening threshold of the check valve 8, and the overflow valve 9 remains closed because the pressure has not exceeded the preset safety value. The fluid is forced to flow from the straight port of the reversing valve 3 into the steel pipe 4 to be tested. During this stage, the safety valve 6 and the on / off valve 7 at the end of the steel pipe 4 to be tested are initially in the open state, and the fluid flows freely from the end of the steel pipe 4 to be tested, discharging the residual air in the steel pipe 4 to be tested (to avoid air compression buffering water hammer pressure, affecting the generation of transient high pressure), until a full-pipe, stable high-speed flow field is formed in the steel pipe 4 to be tested.

[0020] When the system detects that the air in the steel pipe 4 under test has been purged and the water flow rate has reached the standard, the on / off valve 7 at the end of the steel pipe 4 under test is quickly closed within milliseconds. At this time, the fluid moving at high speed in the steel pipe 4 under test changes its motion state suddenly. Based on the principle of water hammer effect, the kinetic energy is instantly converted into pressure energy, forming a transient high pressure that is much higher than the initial pressure.

[0021] The system automatically reads the peak value, duration, and pressure decay curve of transient high pressure through a high-precision pressure sensor: if the peak value reaches the preset test standard and the decay meets the expectations, the performance of the steel pipe 4 under test in bearing dynamic load pressure is deemed qualified; if the peak value does not meet the standard or the pressure drops rapidly, it indicates that the steel pipe 4 under test has structural defects; during the test, if the pressure abnormally exceeds the safety threshold, the safety valve 6 will automatically open to relieve pressure and ensure system safety.

[0022] If the pressure test of the steel pipe 4 is qualified, the motor 1 continues to run or the pressure is appropriately increased to maintain the system pressure above the opening threshold of the check valve 8. The high-pressure fluid overcomes the spring resistance of the check valve 8 to make it conduct, and the system forms a dual-path diversion state. Part of the fluid continues to flow to the straight-through pressure test steel pipe 4, and the other part of the fluid enters the subsequent pipeline through the left port of the reversing valve 3. If the pressure is still close to the safety threshold, the overflow valve 9 remains partially open to assist in adjusting the pressure balance. The water first flows into the chamber 10 of the accumulator. The air spring 11, as the core component of the fluid buffer, weakens the pressure fluctuations generated by the motor 1, ensuring that the fluid pressure flowing into the subsequent pipeline is uniform and the flow rate is stable. The fluid in the chamber 10 continues to flow into the steel pipe 12 to be flushed. The shearing force and impact force generated by the fluid peel off the impurities on the inner wall of the pipeline. The impurities are discharged from the end drain of the steel pipe 12 to be flushed with the fluid. The cleaning effect is judged by observing the quality of the drain water. The cleaning is completed when the drain water is clear and free of obvious impurities.

[0023] The present invention has the following advantages:

[0024] (1) This invention uses the water hammer effect to accurately simulate the transient high pressure of actual working conditions, solving the problem of low fit in traditional static testing; it integrates the "test-cleaning" function, eliminating the need for repeated disassembly and assembly of pipelines, simplifying the process and improving efficiency;

[0025] (2) The present invention ensures system safety through dual buffering of the chamber and accumulator, and dual pressure relief of safety valve and overflow valve; during the cleaning stage, the accumulator stabilizes the water flow pressure to ensure thorough removal of impurities, while avoiding pressure fluctuations that could damage the pipeline, thus taking into account the accuracy of testing, ease of operation and equipment safety. Attached Figure Description

[0026] Figure 1 This is a front view of the overall structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the motor and pump body installation of the present invention;

[0028] Figure 3 This is a schematic diagram of the internal structure of the reversing valve of the present invention;

[0029] Figure 4 This is a schematic diagram of the installation of the safety valve of the present invention;

[0030] Figure 5 This is a schematic diagram of the internal structure of the energy storage device of the present invention;

[0031] The attached diagram is labeled as follows: 1 is the motor, 2 is the pump body, 3 is the reversing valve, 4 is the steel pipe to be tested, 5 is the clamp, 6 is the safety valve, 7 is the on / off valve, 8 is the check valve, 9 is the overflow valve, 10 is the chamber, 11 is the air spring, and 12 is the steel pipe to be flushed. Detailed Implementation

[0032] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are merely further illustrations of the present invention, but the scope of protection of the present invention is not limited to the following embodiments.

[0033] Example 1

[0034] This embodiment relates to an integrated device for dynamic pressure testing and flushing of pipes based on the water hammer effect. (See...) Figure 1 , Figure 2 , Figure 4 As shown, it includes: motor 1, pump body 2, reversing valve 3, steel pipe to be tested 4, clamp 5, safety valve 6, on / off valve 7, check valve 8, overflow valve 9, chamber 10, air spring 11, and steel pipe to be flushed 12.

[0035] Motor 1 is connected to pump body 2. One side of pump body 2 is connected to water tank or oil tank, and the other side is connected to directional valve 3 through flange; this ensures that the fluid does not leak during transportation.

[0036] The reversing valve 3 has two valve outlets; the straight-through valve port is connected to the steel pipe 4 to be tested through a flange and is fixed by a clamp 5.

[0037] The end of the steel pipe 4 to be tested is connected to a short pipe equipped with a safety valve 6 and an on / off valve 7;

[0038] Another valve port of the reversing valve 3 is connected to the pipeline via a flange. The pipeline is equipped with a check valve 8 and an overflow valve 9. The other side of the pipeline is connected to the accumulator via a flange. An air spring 11 is installed in the left half of the accumulator to better stabilize the system pressure. The outlet of the accumulator is connected to the steel pipe 12 to be flushed and is fixed by two clamps 5.

[0039] Furthermore, the motor 1 is cylindrical or square with a shell, and has a fixed bracket at the bottom. One end is connected to an external clean water source, and the other end is connected to the reversing valve 3 through a flange. It can pressurize low-pressure water into high-pressure fluid, providing core power for water pressure testing and pipeline cleaning, and the output pressure can be adjusted by preset parameters.

[0040] Furthermore, the reversing valve 3 is provided with multiple interfaces; wherein the first interface is connected to the water inlet of the motor 1, the second interface is connected to the chamber 10, and the third interface is connected to the steel pipe 4 to be tested.

[0041] Furthermore, the one-way valve 8 has a "valve core + spring" structure. It only allows fluid to flow unidirectionally from the pump motor side to the second pipeline, and is initially closed due to insufficient pressure.

[0042] Furthermore, the overflow valve 9 is connected in parallel with the main system passage and has a pressure relief outlet. It can automatically open to relieve pressure when the system pressure exceeds the safety threshold. The two work together to achieve fluid passage switching and system pressure protection.

[0043] Furthermore, the accumulator is a constant-pressure structure, capable of absorbing pressure shocks caused by water hammer and protecting system components; it can also stabilize system pressure through compression or expansion of the air chamber during pressure fluctuations; when the system requires a large flow rate for a short period, it can release the stored liquid as an auxiliary power source; and it can store liquid when the system flow rate demand is low and release liquid when it is high, reducing pump energy consumption and achieving energy saving. It is installed between the side port of the reversing valve 3 and the steel pipe 12 to be flushed, used to buffer fluid pressure, reduce fluctuations, and stabilize flow rate.

[0044] The second cleaning pipeline of the present invention is connected at one end to the side port of the reversing valve 3 and at the other end to the drain or wastewater collection device. The inner diameter of the pipeline is designed according to the size of the impurities to be cleaned. It can receive the high-pressure fluid after the one-way valve is turned on, and use the flushing force of the high-speed fluid to peel off the impurities on the inner wall and discharge them, thereby realizing the pipeline cleaning function.

[0045] like Figure 2 and 3 As shown, in this invention, the system pressure does not reach the opening threshold of the one-way valve 8, and the overflow valve 10 remains closed because the pressure does not exceed the preset safety value. The fluid is forced to flow into the pipeline from the straight-through port of the reversing valve. At this stage, the parallel safety valve 6 and the on / off valve 7 at the end of the steel pipe are initially in the open state, and the valves are also in the open state. The fluid flows freely from the end of the steel pipe to discharge the residual air in the steel pipe (to avoid air compression buffering water hammer pressure and affecting the generation of transient high pressure). When the water flow stabilizes, the system controls the on / off valve 10 to close quickly within milliseconds. If the pressure exceeds the preset value, the safety valve 6 opens to relieve pressure and protect the pipeline. If the pressure reaches the standard, it can flow through the one-way valve 8 and the overflow valve 9 and then enter the constant pressure structure chamber 10.

[0046] like Figure 5 As shown, when the pressure reaches the standard, the water flow entering the chamber 10 has a high pressure. The water flow first impacts the air spring 11 to reduce the pressure, and then pushes through the rebound of the air spring. The shear force and impact force generated by the fluid are used to peel off the impurities from the inner wall of the pipe. The impurities are discharged from the drain port at the end of the pipe along with the fluid.

[0047] This embodiment also relates to a method for an integrated device for dynamic pressure testing and flushing of pipes based on the water hammer effect, comprising the following steps:

[0048] After turning on the motor 1 switch and starting the pump body 2, the low-pressure water source is pressurized to the preset initial pressure, and the fluid at this pressure is stably delivered to the inlet of the reversing valve 3. At this time, the pressure has not reached the opening threshold of the check valve 8, and the overflow valve 9 remains closed because the pressure has not exceeded the preset safety value. The fluid is forced to flow from the straight port of the reversing valve 3 into the steel pipe 4 to be tested. During this stage, the safety valve 6 and the on / off valve 7 at the end of the steel pipe 4 to be tested are initially in the open state, and the fluid flows freely from the end of the steel pipe 4 to be tested, discharging the residual air in the steel pipe 4 to be tested (to avoid air compression buffering water hammer pressure, affecting the generation of transient high pressure), until a full-pipe, stable high-speed flow field is formed in the steel pipe 4 to be tested.

[0049] When the system detects that the air in the steel pipe 4 under test has been purged and the water flow rate has reached the standard, the on / off valve 7 at the end of the steel pipe 4 under test is quickly closed within milliseconds. At this time, the fluid moving at high speed in the steel pipe 4 under test changes its motion state suddenly. Based on the principle of water hammer effect, the kinetic energy is instantly converted into pressure energy, forming a transient high pressure that is much higher than the initial pressure.

[0050] The system automatically reads the peak value, duration, and pressure decay curve of transient high pressure through a high-precision pressure sensor: if the peak value reaches the preset test standard and the decay meets the expectations, the performance of the steel pipe 4 under test in bearing dynamic load pressure is deemed qualified; if the peak value does not meet the standard or the pressure drops rapidly, it indicates that the steel pipe 4 under test has structural defects; during the test, if the pressure abnormally exceeds the safety threshold, the safety valve 6 will automatically open to relieve pressure and ensure system safety.

[0051] If the pressure test of the steel pipe 4 is qualified, the motor 1 continues to run or the pressure is appropriately increased to maintain the system pressure above the opening threshold of the check valve 8. The high-pressure fluid overcomes the spring resistance of the check valve 8 to make it conduct, and the system forms a dual-path diversion state. Part of the fluid continues to flow to the straight-through pressure test steel pipe 4, and the other part of the fluid enters the subsequent pipeline through the left port of the reversing valve 3. If the pressure is still close to the safety threshold, the overflow valve 9 remains partially open to assist in adjusting the pressure balance. The water first flows into the accumulator chamber 10. The air spring 11, as the core component of the fluid buffer, weakens the pressure fluctuations generated by the motor 1, ensuring that the fluid pressure flowing into the subsequent pipeline is uniform and the flow rate is stable. After the chamber 10 is full of fluid, the fluid flows into the steel pipe 12 to be flushed with a preset tassel. The shearing force and impact force generated by the fluid peel off the impurities on the inner wall of the pipeline. The impurities are discharged from the end drain of the steel pipe 12 to be flushed with the fluid. The cleaning effect is judged by observing the quality of the drain water. The cleaning is completed when the drain water is clear and free of obvious impurities.

[0052] In summary, the pipe dynamic pressure testing and pipe flushing integrated device based on the water hammer effect of this invention is a fluid control structure that integrates "testing-cleaning":

[0053] This invention achieves seamless switching between water hammer testing and high-pressure cleaning by linking the test pipeline and the cleaning pipeline with a reversing valve. It can complete the dual operation without disassembling the pipeline, solving the problem of cumbersome operation of traditional split equipment.

[0054] This invention is a dual pressure buffer and safety pressure relief synergy mechanism: the chamber weakens the initial pressure fluctuation + the accumulator absorbs the water hammer impact in a two-stage buffer design, combined with the dual pressure relief protection of the safety valve at the end of the steel pipe and the system overflow valve, forming a comprehensive pressure safety control system.

[0055] This invention is an integrated design for dynamic testing and stable cleaning based on the water hammer effect: it uses a fast-closing valve to generate transient high pressure to achieve dynamic load testing of pipes, and simultaneously uses an accumulator to stabilize the pressure of the cleaning water flow, so that the same fluid system has both accurate testing and efficient cleaning functions.

[0056] This invention connects all components via standardized flange / threaded interfaces, allowing for flexible replacement of core components such as pumps, pipelines, and valves according to pipe specifications, thus adapting to testing needs of different pipe diameters and materials in various fields.

[0057] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. An integrated device for dynamic pressure testing and flushing of pipes based on the water hammer effect, characterized in that, include: Motor (1), pump body (2), reversing valve (3), steel pipe to be tested (4), clamp (5), safety valve (6), on / off valve (7), check valve (8), overflow valve (9), chamber (10), air spring (11), steel pipe to be flushed (12); The motor (1) is connected to the pump body (2). One side of the pump body (2) is connected to the water tank or oil tank, and the other side is connected to the reversing valve (3) through a flange. The reversing valve (3) has two valve outlets; the straight valve port is connected to the steel pipe (4) to be tested through a flange and is fixed by a clamp (5); The end of the steel pipe (4) to be tested is connected to a short pipe equipped with a safety valve (6) and an on / off valve (7); Another valve port of the reversing valve (3) is connected to the pipeline through a flange. A check valve (8) and an overflow valve (9) are installed in the pipeline. The other side of the pipeline is connected to the accumulator through a flange. An air spring (11) is installed in the left half of the accumulator. The outlet of the accumulator is connected to the steel pipe (12) to be flushed and is fixed by two clamps (5).

2. The integrated device for dynamic pressure testing and flushing of pipes based on water hammer effect as described in claim 1, characterized in that, The motor (1) is cylindrical or square with a shell, with a fixed bracket at the bottom. One end is connected to an external clean water source, and the other end is connected to the reversing valve (3) through a flange.

3. The integrated device for dynamic pressure testing and flushing of pipes based on water hammer effect as described in claim 1, characterized in that, The reversing valve 3 is provided with multiple interfaces; the first interface is connected to the water inlet of the motor (1), the second interface is connected to the chamber (10), and the third interface is connected to the steel pipe (4) to be tested.

4. The integrated device for dynamic pressure testing and flushing of pipes based on water hammer effect as described in claim 1, characterized in that, The one-way valve (8) has a "valve core + spring" structure.

5. The integrated device for dynamic pressure testing and flushing of pipes based on water hammer effect as described in claim 1, characterized in that, The overflow valve (9) is connected in parallel with the main passage of the system and has a pressure relief outlet.

6. The integrated device for dynamic pressure testing and flushing of pipes based on water hammer effect as described in claim 1, characterized in that, The accumulator is a constant pressure structure and is located between the side port of the reversing valve (3) and the steel pipe (12) to be flushed.

7. A method for an integrated device for dynamic pressure testing and flushing of pipes based on the water hammer effect, characterized in that, Includes the following steps: After turning on the motor (1) switch and starting the pump body (2), the low-pressure water source is pressurized to the preset initial pressure, and the fluid at this pressure is stably delivered to the inlet of the reversing valve (3). At this time, the pressure has not reached the opening threshold of the check valve (8), and the overflow valve (9) is closed. The fluid is forced to flow from the straight port of the reversing valve (3) into the steel pipe (4) to be tested. During this stage, the safety valve (6) and the on / off valve (7) at the end of the steel pipe (4) to be tested are initially in the open state. The fluid flows freely from the end of the steel pipe (4) to be tested, and the residual air in the steel pipe (4) to be tested is discharged until a full and stable high-speed flow field is formed in the steel pipe (4) to be tested. When the system detects that the air in the steel pipe (4) under test has been purged and the water flow speed meets the standard, the on / off valve (7) at the end of the steel pipe (4) under test is controlled to close quickly within milliseconds. At this time, the fluid moving at high speed in the steel pipe (4) under test changes its motion state suddenly. Based on the principle of water hammer effect, the kinetic energy is instantly converted into pressure energy, forming a transient high pressure that is much higher than the initial pressure. The system automatically reads the peak value, duration and pressure decay curve of transient high pressure through a high-precision pressure sensor: if the peak value reaches the preset test standard and the decay meets the expectations, it is determined that the performance of the steel pipe (4) under test in bearing dynamic load pressure is qualified; if the peak value does not meet the standard or the pressure drops rapidly, it indicates that there is a structural defect in the steel pipe (4) under test. If the pressure test steel pipe (4) passes the test, the motor (1) continues to run or the pressure is appropriately increased to keep the system pressure above the opening threshold of the check valve (8). The high-pressure fluid overcomes the spring resistance of the check valve (8) to make it conduct. The system forms a dual-path diversion state. Part of the fluid continues to flow to the straight-through pressure test steel pipe (4), and the other part of the fluid enters the subsequent pipeline through the left port of the reversing valve (3). If the pressure is still close to the safety threshold, the overflow valve (9) remains partially open to assist in adjusting the pressure balance. The water first flows into the chamber (10) of the accumulator. The air spring (11) weakens the pressure fluctuation generated by the motor (1). The fluid continues to flow into the steel pipe (12) to be flushed. Impurities are discharged from the end drain port of the steel pipe (12) to be flushed along with the fluid. The cleaning effect is judged by observing the quality of the drain water. The cleaning is completed when the drain water is clear and free of obvious impurities.

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