A sealing performance testing device for long-shaft submersible pumps

Abstract

This application relates to the field of centrifugal pump sealing performance testing technology, specifically disclosing a sealing performance testing device for a long-shaft submersible pump. The device includes a testing assembly comprising a stand, a testing tank, a pressurizing component, and a liquid injection component. A controller is mounted on the stand. The pressurizing component is used to inject gaseous medium into the sealing cavity for sealing testing. The liquid injection component is used to provide liquid medium to the long-shaft submersible pump to simulate actual applications and works in conjunction with the pressurizing component for sealing performance testing. The drive assembly includes a first motor and a transmission component. The transmission component is mounted on the shaft housing, and the first motor is driven to the pump shaft via the transmission component. The load assembly includes a piston cylinder, a load piston, and a load drive component. The piston cylinder is mounted on the transmission component, and the load piston is installed inside the piston cylinder. The load drive component is driven to the load piston and is used to cyclically apply impact loads to the pump shaft. This application improves the reliability and accuracy of sealing performance testing.

Description

Technical Field

[0001] This application relates to the field of centrifugal pump sealing performance testing technology, and in particular to a sealing performance testing device for a long-shaft submersible pump. Background Technology

[0002] Long-shaft submersible pumps are special pumps where the motor is located above the liquid surface, and the pump body and long shaft are constantly immersed in the liquid medium. They are widely used in petrochemical, metallurgical, power, environmental protection, and municipal engineering fields, and are especially suitable for conveying media that are corrosive, at high temperatures, or contain solid particles. Because of the long drive shaft of this type of pump, the shaft system needs to pass through multiple support points and extend to the submersible pump body. Its sealing structure not only prevents axial leakage of the conveyed medium, but also plays a crucial role in isolating the external environment and preventing air, moisture, or impurities from entering the pump chamber and bearing chamber.

[0003] Existing long-shaft submersible pumps typically include a drive motor, pump shaft, shaft housing, pump body, impeller, and shaft seal assembly. The shaft housing is coaxially mounted on the pump body, and the pump shaft is installed inside the shaft housing, forming a sealed cavity between them. A receiving cavity is provided within the pump body, and the impeller is installed within this cavity. One end of the pump shaft passes through the pump body and extends into the receiving cavity to connect with the impeller. The pump shaft transmits power from the motor to the submersible impeller. The shaft seal assembly is generally located at the connection between the pump body and the shaft housing, and near the drive motor on the shaft housing. It seals the medium while the pump shaft is rotating. Common forms include packing seals, mechanical seals, or combinations thereof. The sealing performance of long-shaft submersible pumps is typically tested using static or quasi-static methods. For example, after assembly, a local pressure test is performed on the receiving cavity by applying a certain pressure of gas or liquid medium into the cavity, and the pressure retention or leakage is observed.

[0004] In practical engineering applications, due to the large span and significant flexibility of the shaft system of long-shaft submersible pumps, they are inevitably affected by factors such as the fluid force of the medium, rotor imbalance force, and installation errors during actual operation. This leads to dynamic operating conditions such as axial movement, radial runout, and periodic vibration. These dynamic factors often act cumulatively on the shaft seal area, placing the sealing interface in a non-ideal stress state. This makes the submersible pump more prone to bending deformation and dynamic runout during operation, especially at high speeds or when the medium conditions fluctuate, the shaft seal will bear a complex load that changes over time. In this situation, even if a sealing structure is deemed qualified under static testing conditions, it may still experience uneven stress on the sealing lip and periodic changes in the sealing gap due to minor shaft deformation, vibration, or eccentricity during actual operation, gradually leading to potential leakage. Such problems are often difficult to effectively identify during the testing phase, resulting in discrepancies between the test results and the actual operating conditions. This not only affects the pump's operational reliability but may also increase subsequent maintenance costs and safety risks. Summary of the Invention

[0005] This application provides a sealing performance testing device for a long-shaft submersible pump. The testing device can simultaneously simulate the actual rotational conditions of the long-shaft submersible pump and the dynamic stress state of the shaft system under controlled conditions, thereby achieving dynamic and identifiable testing of the sealing performance of the shaft seal assembly.

[0006] This application provides a sealing performance testing device for a long-shaft submersible pump, which adopts the following technical solution: A sealing performance testing device for a long-shaft submersible pump, comprising: The testing assembly includes a stand, a testing tank, a pressurizing component, and a liquid injection component. The stand is mounted on the testing tank and has a controller. The pressurizing component is mounted on the stand, and the liquid injection component is mounted on the testing tank. The pressurizing component is used to inject gaseous medium into the sealing cavity for sealing tests, and the liquid injection component is used to provide liquid medium to the long-shaft submersible pump to simulate actual applications and cooperate with the pressurizing component to perform sealing tests. A drive assembly includes a first motor and a transmission component. The transmission component is disposed on one end of a shaft housing and has a first output end and a second output end. The first motor is connected to the transmission component in a transmission connection. The first output end is connected to one end of a pump shaft. The first motor is electrically connected to the controller. The load assembly includes a piston cylinder, a load piston, and a load drive. One end of the piston cylinder is driven to a second output end. The load piston is slidably disposed within the piston cylinder. The load drive is disposed at the end of the piston cylinder opposite to the drive member and is driven to the load piston. The load drive is used to drive the load piston to reciprocate within the piston cylinder, thereby causing the load piston to cyclically apply an impact load to the pump shaft.

[0007] By adopting the above technical solution, the detection component, drive component, and load component are integrated, allowing the long-shaft submersible pump to simultaneously operate in a liquid medium environment, under pump shaft rotation, and under periodic impact loads during the sealing test. This creates a dynamic sealing test condition that differs from existing static or quasi-static testing methods. Specifically, a liquid injection component supplies liquid medium to the pump body, ensuring the environment of the shaft seal and pump shaft matches the actual submersible operating conditions. Furthermore, a pressurizing component injects gas medium into the sealing cavity for pressurization testing, placing the sealing structure under dynamic stress while bearing the medium pressure. Simultaneously, the drive component rotates the pump shaft, and the load component cyclically applies impact loads to the pump shaft, actively introducing dynamic factors such as shaft yaw, vibration, and transient loading. This allows potential sealing failures caused by shaft flexibility deformation or uneven stress to be exposed early during the testing phase, preventing situations where static testing is successful but leakage occurs during actual operation. This significantly improves the consistency and reliability between the sealing test results and the actual operating state of the long-shaft submersible pump.

[0008] Optionally, the pressurizing component includes an air pump, an air tank, and a pressure sensor. The air pump and the air tank are both fixed on the upright. The air tank is filled with ammonia. The air pump is electrically connected to the controller. The input end of the air pump is connected to the air tank, and the output end of the air pump is connected to the sealing cavity. The pressure sensor is mounted on the shaft housing and is electrically connected to the controller. The pressure sensor can be used to monitor the pressure changes inside the sealing cavity in real time.

[0009] By adopting the above technical solution, the pressurizing component is configured to include an air pump, an air tank, and a pressure sensor, with the pressure sensor directly mounted on the shaft housing. This allows for real-time monitoring of the internal pressure of the sealing cavity, forming a detection structure that continuously feeds back pressure changes in the sealing cavity under dynamic testing conditions. Compared to existing technologies that only observe static pressure holding after pressurization, this configuration can capture pressure fluctuations in the sealing cavity caused by shaft vibration, deflection, or transient impacts in real time during pump shaft rotation and the application of periodic impact loads by the load components. When the sealing interface experiences gap changes or instantaneous failure under dynamic stress conditions, the pressure inside the sealing cavity will decrease or fluctuate abnormally. The pressure sensor can immediately feed back this change to the controller, enabling dynamic judgment of sealing performance.

[0010] Optionally, the liquid injection component includes a storage tank and a pH sensor. The storage tank is disposed on the outer wall of the detection pool, and the detection pool and the storage tank are interconnected. Both the detection pool and the storage tank are filled with liquid medium. A drain pipe is disposed on the pump body and is connected to the storage tank. The pH sensor is disposed inside the storage tank and is electrically connected to the controller. The pH sensor is used to monitor the pH value of the liquid medium in the storage tank.

[0011] By adopting the above technical solution, a storage tank connected to the testing pool is set up to provide a sufficient and stable liquid medium for the long-shaft submersible pump during the testing process. This allows for a realistic simulation of the liquid environment inside the impeller and pump body cavity under actual operating conditions. The installed pH sensor can monitor the pH value of the liquid medium in real time. When the shaft seal assembly near the impeller fails, the ammonia gas injected into the sealing cavity will permeate into the pump body cavity along the pump shaft or through the sealing gap. Under the action of impeller rotation, it will gradually dissolve in the liquid medium in the testing pool and storage tank, causing an abnormal change in the pH value of the water, thereby achieving the sealing test of the long-shaft submersible pump.

[0012] Optionally, the transmission component includes a connecting shell, a transmission shaft, a driving bevel gear, and a driven bevel gear. The connecting shell is located at the end of the shaft housing away from the pump body. The transmission shaft rotatably passes through the connecting shell. The first motor is fixed to the connecting shell. The driving bevel gear and the driven bevel gear are located inside the connecting shell. The driving bevel gear is fixed to the output end of the first motor. The driven bevel gear is coaxially and fixedly connected to the transmission shaft. The driving bevel gear and the driven bevel gear mesh. One end of the transmission shaft is connected to the pump shaft, and the other end of the transmission shaft is rotatably connected to one end of the piston cylinder.

[0013] By adopting the above technical solution, a connecting shell is set at the end of the shaft housing away from the pump body, and a meshing transmission structure of active and driven bevel gears is used in the connecting shell. This allows the output power of the first motor to be transmitted to the pump shaft and the piston cylinder where the load assembly is located while changing the transmission direction. This achieves a reasonable distribution and concentrated arrangement of power within a limited axial space. At the same time, since the pump shaft and the load assembly share the same transmission shaft as the power reference, it can be ensured that the rotation state of the pump shaft and the application of the impact load are highly consistent in time and phase during the testing process. This allows the rotational load and axial impact load borne by the shaft seal area to form a stable and repeatable superposition relationship, thereby more realistically simulating the complex dynamic working condition of a long-shaft submersible pump in actual operation, which is driven by a motor and superimposed with fluid force and shaft disturbance.

[0014] Optionally, the load drive component includes a mounting housing, a second motor, a drive disk, and a pull rod. The piston cylinder is fixed on the side of the connecting housing opposite to the shaft housing. The mounting housing is fixed on the end of the piston cylinder opposite to the connecting housing. The second motor is fixed on the mounting housing and electrically connected to the controller. The drive disk is disposed inside the mounting housing and is fixedly connected to the output end of the second motor. A connecting shaft is fixed on the drive disk and is eccentrically disposed with respect to the drive disk. One end of the pull rod is rotatably connected to the connecting shaft, and the other end of the pull rod is rotatably connected to the load piston. The load piston, the pull rod, and the drive disk combine to form a crank-slider mechanism.

[0015] By adopting the above technical solution, and by setting the load drive component as a crank-slider mechanism driven by a second motor, the load piston can achieve stable and controllable reciprocating motion within the piston cylinder. Furthermore, it can convert rotational motion into periodic linear impact loads. By adjusting the speed of the second motor, precise control of the impact frequency and amplitude can be achieved. This enables the detection device to cover various shaft dynamic load conditions under different operating conditions, improving the adaptability and adjustment flexibility of the detection.

[0016] Optionally, an impact piston is slidably disposed inside the piston cylinder, the impact piston is located between the load piston and the drive shaft, and a filling cavity is disposed between the impact piston and the load piston, the filling cavity being filled with an inert gas medium.

[0017] By adopting the above technical solution, an impact piston is added inside the piston cylinder, and a filling cavity filled with inert gas is formed between the load piston and the impact piston. This gives the impact load buffering and adjustment capabilities during transmission, avoiding the direct action of rigid impact on the pump shaft. Thus, without damaging the pump shaft or detection device, the non-ideal, non-instantaneous impact load borne by the shaft system in actual operation is simulated, making the applied load closer to the dynamic force characteristics under real working conditions.

[0018] Optionally, the mounting housing is provided with an adjusting component for adjusting the volume of the filling cavity. The adjusting component includes a gas cylinder, an injection pipe, and a displacement driving component. The gas cylinder is fixed on the upright frame, the injection pipe is slidably disposed within the mounting housing, and an air inlet is provided through the load piston. One end of the injection pipe is movably inserted into the air inlet, and the other end of the injection pipe is connected to the gas cylinder. The displacement driving component is fixed on the mounting housing and electrically connected to the controller. The output end of the displacement driving component is connected to the injection pipe, and the displacement driving component can drive the injection pipe to reciprocate within the mounting housing. A first opening and closing component is provided within the air inlet, which is used to movably block the air inlet. A second opening and closing component is provided at the end of the injection pipe near the air inlet, which is used to control the amount of gas injected into the injection pipe, thereby controlling the volume of the filling cavity.

[0019] By adopting the above technical solution, the adjustable components include a gas cylinder, an axially displaceable gas injection pipe, and a displacement drive controlled by a controller. Simultaneously, a first opening and closing component and a second opening and closing component are provided to construct a controllable, repeatable, and online adjustable impact load adjustment mechanism. Specifically, the displacement drive component drives the gas injection pipe to reciprocate within the mounting housing, ensuring that the gas injection pipe only connects to the filling cavity under the coordinated action of the first and second opening and closing components when it is inserted into the air inlet of the load piston. This allows inert gas to be injected into the filling cavity and changes the... The effective volume of the filling chamber; when the air injection pipe is disconnected from the air inlet, the air inlet and the air injection pipe are automatically sealed by the corresponding opening and closing parts, so that the filling chamber maintains a stable closed state; in this way, the gas volume of the filling chamber can be finely adjusted without disassembling the load components, stopping the machine or replacing mechanical parts, thereby realizing continuous adjustable control of the impact load, flexibly matching its dynamic load characteristics in actual operation, significantly improving the consistency between the sealing test conditions and the actual operating conditions, and avoiding detection distortion or misjudgment due to unreasonable load settings.

[0020] Optionally, the first opening and closing component includes a sealing plug and a clamping spring. A support portion is fixedly provided on the side of the load piston facing the impact piston. The support portion is mounted on the air inlet. A sliding rod is fixedly provided on the sealing plug. The sealing plug is slidably disposed on the support portion via the sliding rod and is movably disposed within the air inlet. The clamping spring is sleeved on the sliding rod. One end of the clamping spring is connected to the sealing plug, and the other end of the clamping spring is connected to the support portion.

[0021] By adopting the above technical solution, a first opening and closing component with an elastic reset structure is set up to automatically control the opening and closing of the air inlet on the load piston, so that the filling cavity maintains good sealing performance in the non-injection state, effectively preventing gas leakage or abnormal pressure fluctuation in the filling cavity during the test, ensuring the stability and controllability of the impact load adjustment process, thereby improving the reliability and repeatability of the test process.

[0022] Optionally, the second opening / closing component includes a clamping plug and a return spring. A support portion is fixed inside the air injection pipe. An extension rod is fixed on one side of the clamping plug. The clamping plug is slidably disposed on the support portion via the extension rod. An abutment portion is fixed on the side of the clamping plug facing away from the extension rod. The abutment portion is slidably connected to the air injection pipe, and the end of the abutment portion facing away from the clamping plug is in movable contact with the sealing plug. The return spring is sleeved on the extension rod. One end of the return spring is connected to the clamping plug, and the other end of the return spring is connected to the support portion. The clamping plug movably seals the air injection pipe under the action of the return spring. When the displacement driving component drives the air injection pipe to be inserted into the air inlet, the air inlet and the air injection pipe are connected under the action of the abutment portion.

[0023] By adopting the above technical solution, and utilizing the second opening and closing component, which works in conjunction with the first opening and closing component, the connection is achieved only under specific conditions where the air injection pipe is inserted into the air inlet. In other conditions, the air injection channel is automatically blocked, effectively avoiding accidental air injection or unexpected pressure relief. This ensures the safety and accuracy of the filling cavity volume adjustment process, makes the adjustment of impact load parameters more controllable, and further improves the stability and safety of the sealing performance testing device under complex dynamic testing conditions.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. By integrating the detection component, drive component, and load component, the long-shaft submersible pump is simultaneously subjected to a liquid medium environment, pump shaft rotation, and periodic impact load during the sealing test, thus constructing a dynamic sealing test condition. The drive component drives the pump shaft to rotate, and the load component applies impact loads to the pump shaft cyclically. This exposes potential sealing failures caused by shaft flexibility deformation or uneven stress in advance during the testing phase, avoiding situations where static testing is qualified but leakage occurs during actual operation. This significantly improves the consistency and reliability between the sealing test results and the actual operating state of the long-shaft submersible pump. 2. A pressure sensor is directly mounted on the shaft housing to monitor the internal pressure of the sealing cavity in real time. The liquid storage tank is connected to the detection pool to provide a stable liquid medium for the detection process, thus realistically simulating the liquid environment of the submersible pump during actual operation. During the rotation of the pump shaft and the application of periodic impact loads by the load components, if the sealing interface experiences gap changes or instantaneous failure under dynamic stress conditions, the pressure inside the sealing cavity will decrease or change abnormally, and the pressure sensor will immediately feed back to the controller. At the same time, the ammonia gas added to the sealing cavity enters the pump body cavity through the sealing gap and dissolves in the liquid medium, causing abnormal changes in the pH value. This, combined with the pH sensor installed in the liquid storage tank, forms a continuous feedback detection mechanism suitable for dynamic detection conditions, thereby realizing multi-parameter, dynamic joint detection of the sealing performance of the long-shaft submersible pump. 3. The adjustable components include a gas cylinder, an axially displaceable gas injection pipe, and a displacement drive controlled by a controller. These, along with a first and second opening / closing component, create a controllable, repeatable, and online adjustable impact load adjustment mechanism. This mechanism allows for adjustment of the gas volume in the filling chamber without disassembling the load assembly, stopping the machine, or replacing mechanical parts. This enables continuous and adjustable control of the impact load, flexibly matching the dynamic load characteristics during actual operation. It significantly improves the consistency between the sealing test conditions and the actual operating conditions, avoiding detection distortion or misjudgment due to unreasonable load settings. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the long-shaft submersible pump in the embodiments of this application.

[0026] Figure 2 This is a schematic diagram of the overall structure of the long-shaft submersible pump sealing performance testing device in this application embodiment.

[0027] Figure 3 This is a partial cross-sectional schematic diagram of the load component in an embodiment of this application.

[0028] Figure 4 This is an exploded view of the first opening / closing component in an embodiment of this application.

[0029] Reference numerals: 1. Detection component; 11. Stand; 12. Detection tank; 13. Pressurizing component; 131. Air pump; 132. Air storage tank; 133. Pressure sensor; 14. Liquid injection component; 141. Liquid storage tank; 142. pH sensor; 15. Controller; 2. Drive assembly; 21. First motor; 22. Transmission component; 221. Connecting housing; 222. Drive shaft; 223. Driving bevel gear; 224. Driven bevel gear; 3. Load assembly; 31. Piston cylinder; 311. Filling chamber; 32. Load piston; 321. Air inlet; 322. Support part; 33. Load drive component; 331. Mounting shell; 332. Second motor; 333. Drive disc; 3331. Connecting shaft; 334. Pull rod; 34. Impact piston; 35. Adjusting component; 351. Gas cylinder; 352. Gas injection pipe; 3521. Bearing part; 353. Displacement drive component; 36. First opening and closing component; 361. Sealing plug; 3611. Sliding rod; 362. Pressing spring; 37. Second opening and closing component; 371. Pressing plug; 3711. Extension rod; 3712. Abutment part; 372. Return spring; 41. Drive motor; 42. Pump shaft; 43. Shaft housing; 431. Sealing cavity; 44. Pump body; 441. Receiving cavity; 45. Impeller; 46. Shaft seal assembly. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail below.

[0031] This application discloses a sealing performance testing device for a long-shaft submersible pump.

[0032] It should be noted that, referring to Figure 1 A long-shaft submersible pump typically includes a drive motor 41, a pump shaft 42, a shaft housing 43, a pump body 44, an impeller 45, and a shaft seal assembly 46. The shaft housing 43 is coaxially mounted on the pump body 44. The drive motor 41 is mounted at one end of the shaft housing 43. The pump shaft 42 is mounted inside the shaft housing 43, and the output end of the drive motor 41 is connected to one end of the pump shaft 42. A sealing cavity 431 is formed between the pump shaft 42 and the shaft housing 43. A receiving cavity 441 is provided inside the pump body 44, and the impeller 45 is mounted in the receiving cavity 441. Inside, the end of the pump shaft 42 away from the drive motor 41 passes through the pump body 44 and extends into the receiving cavity 441 to connect with the impeller 45. The pump shaft 42 is used to transmit the power of the motor to the submersible impeller 45. The shaft seal assembly 46 is generally set at the connection position between the pump body 44 and the shaft housing 43 and at the position of the shaft housing 43 near the drive motor 41. In this embodiment, the long shaft submersible pump shaft 42 seal assembly adopts a mechanical seal. There are two sets of shaft seal assemblies 46, and the two sets of shaft seal assemblies 46 are respectively installed at both ends of the shaft housing 43.

[0033] Reference Figure 2 A sealing performance testing device for a long-shaft submersible pump includes a testing component 1, a drive component 2, and a load component 3. The long-shaft submersible pump to be tested is mounted on the testing component 1, while the drive component 2 and load component 3 are mounted on the pump. The load component 3 is located on one side of the drive component 2. The testing component 1 is used to perform sealing performance testing on the long-shaft submersible pump, the drive component 2 is used to drive the pump shaft 42 to rotate, thereby simulating the normal operating state of the long-shaft submersible pump, and the load component 3 is used to apply impact loads to the pump shaft 42, thereby simulating the dynamic working conditions such as shaft stress during actual operation.

[0034] Reference Figure 2 In this embodiment, the detection component 1 includes a detection pool 12, a support frame 11, a controller 15, a pressurizing component 13, and a liquid injection component 14. The support frame 11 is erected above the detection pool 12, the controller 15 is fixed on the support frame 11, the pressurizing component 13 is installed on the support frame 11, and the liquid injection component 14 is installed on the outer wall of the detection pool 12. The pressurizing component 13 includes an air pump 131, a gas storage tank 132, a plug, and a pressure sensor 133. The air pump 131 and the gas storage tank 132 are both fixed on the support frame 11. The air pump 131 is located on one side of the gas storage tank 132. The gas storage tank 132 is filled with ammonia. The air pump 131 is electrically connected to the controller 15. The air pump 131 can be a gas booster pump. A first connecting pipe is fixed on the gas storage tank 132. One end of the first connecting pipe is connected to the input end of the air pump 131, and a second connecting pipe is fixed on the output end of the air pump 131.

[0035] The shaft housing 43 is provided with a first connecting hole and a second connecting hole respectively. One end of the second connecting pipe is connected to the first connecting hole. The air pump 131 injects gas medium into the sealing cavity 431 through the first connecting hole. The plug is provided on the second connecting hole. The second connecting hole is provided with an internal thread. The plug is connected to the second connecting hole with the sealing thread. The pressure sensor 133 is fixed on the plug. The pressure sensor 133 is electrically connected to the controller 15. The pressure sensor 133 can be used to monitor the pressure change inside the sealing cavity 431 in real time.

[0036] The liquid injection unit 14 includes a storage tank 141 and a pH sensor 142. The storage tank 141 is located on one side of the detection pool 12 and is filled with water. A first injection pipe and a second injection pipe are fixed to the storage tank 141. One end of the first injection pipe is connected to the outlet of the storage tank 141, and the other end is connected to the detection pool 12. The detection pool 12 and the storage tank 141 are interconnected. A drain pipe is provided on the pump body 44. One end of the second injection pipe is connected to the drain pipe, and the other end is connected to the storage tank 141. The detection pool 12 contains water of a certain depth. The pH sensor 142 is fixed inside the storage tank 141 and is electrically connected to the controller 15. The pH sensor 142 is used to monitor the pH value of the water in the storage tank 141. When the long-shaft submersible pump to be tested is installed on the stand 11, the suction end of the long-shaft submersible pump is immersed in the detection pool 12.

[0037] Reference Figure 2 and Figure 3 In this embodiment, the drive assembly 2 includes a first motor 21, a transmission component 22, and a transmission shaft 222. In this embodiment, the first motor 21 is a stepper motor identical to the drive motor 41, and is electrically connected to the controller 15. The transmission component 22 includes a connecting housing 221, a driving bevel gear 223, and a driven bevel gear 224. The connecting housing 221 is detachably mounted on the end of the shaft housing 43 away from the pump body 44 by bolts. The transmission shaft 222 rotatably passes through the connecting housing 221. 1. Fixed on the connecting shell 221, the driving bevel gear 223 and the driven bevel gear 224 are disposed inside the connecting shell 221. The driving bevel gear 223 is fixed on the output end of the first motor 21. The driven bevel gear 224 is coaxially fixedly connected to one end of the transmission shaft 222. The driving bevel gear 223 and the driven bevel gear 224 mesh. A coupling is fixed on the end of the transmission shaft 222 away from the driven bevel gear 224. The transmission shaft 222 is connected to the pump shaft 42 through the coupling. The first motor 21 can drive the pump shaft 42 to rotate.

[0038] In this embodiment, the active bevel gear 223 is set as the input end, the end of the drive shaft 222 near the pump shaft 42 is set as the first output end, and the other end of the drive shaft 222 is set as the second output end.

[0039] In other embodiments of this application, the first motor 21 can be eliminated, and the drive motor 41 on the original long-shaft submersible pump can be directly installed on the connecting housing 221; in addition, the bevel gear transmission mechanism can be replaced with a worm gear transmission mechanism, that is, the driving bevel gear 223 can be replaced with a worm, and the driven bevel gear 224 can be replaced with a worm. However, since the worm gear is a reduction transmission mechanism, it needs to be selectively applied according to actual needs.

[0040] Reference Figure 2 and Figure 3In this embodiment, the load assembly 3 includes a piston cylinder 31, a load piston 32, an impact piston 34, a load drive component 33, an adjustment component 35, a first opening and closing component 36, and a second opening and closing component 37. The piston cylinder 31 is fixed on the connecting shell 221 and is coaxially arranged with the pump shaft 42. One end of the piston is rotatably connected to the end of the transmission shaft 222 away from the pump shaft 42. The load piston 32 and the impact piston 34 are both slidably arranged in the piston cylinder 31. The impact piston 34 is located between the transmission shaft 222 and the load piston 32. The side of the impact piston 34 away from the load piston 32 is in movable contact with the end of the transmission shaft 222 away from the pump shaft 42. A filling cavity 311 is formed between the load piston 32 and the impact piston 34. The filling cavity 311 is filled with a gaseous medium. In this embodiment, the filling cavity 311 is filled with nitrogen.

[0041] The load drive component 33 includes a mounting shell 331, a second motor 332, a drive disk 333, and a pull rod 334. The mounting shell 331 is fixed on the end of the piston cylinder 31 away from the connecting shell 221. The mounting shell 331 is a rectangular box. The second motor 332 is fixed on the mounting shell 331. The second motor 332 can be a servo motor. The second motor 332 is electrically connected to the controller 15. The drive disk 333 is located inside the mounting shell 331 and is fixedly connected to the output end of the second motor 332. A connecting shaft 3331 is fixed on the drive disc 333. The connecting shaft 3331 is eccentrically set with the drive disc 333. A relief groove is opened on the side of the load piston 32 away from the impact piston 34. A connecting part is fixed in the relief groove. One end of the pull rod 334 is rotatably connected to the connecting shaft 3331, and the other end of the pull rod 334 is rotatably connected to the connecting part. The second motor 332 drives the drive disc 333 to rotate, thereby driving the load piston 32 to reciprocate within the piston cylinder 31 through the pull rod 334, thereby driving the impact piston 34 to apply an impact load to one end of the transmission shaft 222.

[0042] An adjusting component 35 is mounted on the mounting housing 331. The adjusting component 35 includes a gas cylinder 351, an injection pipe 352, and a displacement driving component 353. The gas cylinder 351 is fixed to the support frame 11 and is filled with high-pressure nitrogen. A sliding seat is fixed to the inner wall of the mounting housing 331. The injection pipe 352 is a cylindrical tube with one end closed, and it slides through the sliding seat. A gas delivery pipe is fixed to the gas cylinder 351, and the closed end of the injection pipe 352 is connected to the gas delivery pipe. The injection pipe 352 is connected to the gas cylinder 351 through the gas delivery pipe. The displacement driving component 353 is fixed to the mounting housing 331 and can be configured as a cylinder. The displacement driving component 353 is electrically connected to the controller 15. The output end of the displacement drive 353 extends into the mounting housing 331. The output end of the displacement drive 353 is fixedly connected to one end face of the air injection pipe 352 which is closed. The displacement drive 353 can drive the air injection pipe 352 to slide back and forth in the mounting housing 331. An air inlet 321 is provided through the load piston 32. The end of the air injection pipe 352 away from the air supply pipe is movably inserted into the air inlet 321. The first opening and closing member 36 is installed in the air inlet 321. The first opening and closing member 36 can movably block the air inlet 321. The second opening and closing member 37 is installed at one end of the air injection pipe 352. The second opening and closing member 37 is used to control the amount of air injected into the air injection pipe 352, thereby controlling the volume of the filling cavity 311.

[0043] Reference Figure 3 In this embodiment, the first opening and closing member 36 includes a sealing plug 361 and a pressing spring 362. A support portion 322 is fixedly provided on the side of the load piston 32 facing the impact piston 34. The support portion 322 is mounted on the air inlet 321. A sliding rod 3611 is fixedly provided on the sealing plug. The sliding rod 3611 slides through the support portion 322. The sealing plug 361 slides through the sliding rod 3611 on the support portion 322 and is movably disposed in the air inlet 321. The pressing spring 362 is sleeved on the sliding rod 3611. One end of the pressing spring 362 is fixedly connected to the sealing plug 361, and the other end of the pressing spring 362 is fixedly connected to the support portion 322.

[0044] The second opening and closing component 37 includes a stop plug 371 and a return spring 372. A support portion 3521 is fixedly provided at one end of the air injection pipe 352 facing the load piston 32. The support portion 3521 is mounted inside the air injection pipe 352. An extension rod 3711 is fixedly provided on the stop plug 371. The extension rod 3711 slides through the support portion 3521. The stop plug 371 is slidably mounted on the support portion 3521 through the extension rod 3711. An abutment portion 3712 is fixedly provided on the side of the stop plug 371 facing away from the extension rod 3711. The abutment portion 3712 is slidably connected to the air injection pipe 352. The end of the air injection pipe 352 facing the air inlet 321 is set in a constricted manner. In the initial state, the abutment portion 3712 extends out of the air injection pipe 352, and the stop plug 371 just blocks the air injection pipe 352.

[0045] A return spring 372 is sleeved on an extension rod 3711. One end of the return spring 372 is fixedly connected to a stop plug 371, and the other end is fixedly connected to a bearing part 3521. The stop plug 371, under the action of the return spring 372, provides a movable seal to the injection tube 352. It should be noted that the elastic coefficient of the return spring 372 is greater than that of the stop spring 362. Therefore, when the displacement drive 353 drives the injection tube 352 to be inserted into the air inlet 321, the side of the sealing plug 361 facing away from the sliding rod 3611 abuts against the abutment part 3712. The abutment part 3712 pushes the sealing plug 361 out of the air inlet 321, and then the abutment part 3712 moves into the injection tube 352, thereby connecting the injection tube 352 with the filling cavity 311, and the nitrogen in the gas cylinder 351 is then injected into the filling cavity 311.

[0046] In this embodiment, both the sealing plug 361 and the clamping plug 371 are made of hard rubber. The piston cylinder 31 is provided with a pressure relief port, and an electromagnetic pressure relief valve is fixed inside the pressure relief port. The electromagnetic pressure relief valve is electrically connected to the controller 15.

[0047] More specifically, the second motor 332 drives the drive disc 333 to rotate, and the pull rod 334 drives the load piston 32 to slide back and forth in the piston cylinder 31. During this period, the controller 15 can drive the gas injection pipe 352 to be inserted into the air inlet 321 through the displacement drive component 353. The first opening and closing component 36 and the second opening and closing component 37 abut against each other and open. The gas injection pipe 352 injects nitrogen into the filling cavity 311. The volume of the filling cavity 311 can be changed according to the degree and frequency of the gas injection pipe 352 being inserted into the air inlet 321, thereby changing the impact load of the impact piston 34 acting on one end of the transmission shaft 222.

[0048] As the drive shaft 222 drives the pump shaft 42 to rotate, simulating the actual operating conditions of a long-shaft submersible pump, the water in the detection pool 12 will be injected into the storage tank 141 through the drain pipe and the second injection pipe under the action of the impeller 45. At the same time, ammonia gas is added to the sealing cavity 431, and the impact piston 34 transmits the axial impact load to the pump shaft 42 through the drive shaft 222. After a period of operation, if the shaft seal assembly 46 on the pump shaft 42 is damaged and the seal fails, the pressure in the corresponding sealing cavity 431 will decrease. If the shaft seal assembly 46 near the receiving cavity 441 fails, due to the molecular weight of ammonia gas... If the ammonia gas is small and has strong permeability, it will seep from the failed shaft seal assembly 46 into the receiving cavity 441. Since ammonia gas is highly soluble in water, the pH value of the water in the detection pool 12 and the storage tank 141 will gradually become alkaline. Therefore, once the pH value of the water in the storage tank 141 is detected to increase, it indicates that the shaft seal assembly 46 on the pump shaft 42 near the impeller 45 has failed to seal. In this way, the actual rotational conditions and dynamic stress state of the shaft system of the long-shaft submersible pump can be simulated under controlled conditions. Combined with pressure change and medium characteristic detection, dynamic and identifiable detection of the sealing performance of the shaft seal assembly 46 can be achieved.

[0049] The implementation principle of the long-shaft submersible pump sealing performance testing device in this application embodiment is as follows: First, the long-shaft submersible pump to be tested is installed on the stand 11, with its suction end immersed in the testing pool 12. The first motor 21 drives the pump shaft 42 to rotate via the transmission component 22, causing the impeller 45 to run in the testing pool 12, thereby simulating the continuous rotation state of the submersible pump under actual working conditions. At the same time, the testing component 1 injects gas medium into the sealing cavity 431 formed between the pump shaft 42 and the shaft housing 43 through the pressurizing component 13, so that the sealing cavity 431 is under a certain degree of pressure, and the pressure sensor 133 monitors the pressure change in the sealing cavity 431 in real time. While the pump shaft 42 rotates, the load assembly 3 applies a periodic impact load to it. Specifically, the load drive 33 drives the load piston 32 to reciprocate within the piston cylinder 31. Through the compression and release of the gas medium in the filling chamber 311, the impact piston 34 periodically acts on the end of the transmission shaft 222, thereby transmitting the axial impact load to the pump shaft 42. The adjustment component 35 adjusts the gas volume and injection rate in the filling chamber 311 according to actual needs, which can change the magnitude and frequency of the impact load, thereby simulating the complex working conditions such as axial movement and vibration caused by fluid force, rotor imbalance and structural flexibility in the actual operation of the long-shaft submersible pump. Under the combined effects of rotation and dynamic load, the shaft seal assembly 46 on the pump shaft 42 is forced into a non-ideal stress state. When the sealing performance of any shaft seal assembly 46 decreases or fails, the pressure in its corresponding sealing cavity 431 will change abnormally. The pressure sensor 133 can capture this change in real time to determine the sealing status of the shaft seal. Furthermore, when the shaft seal assembly 46 near the impeller 45 fails to seal, the gas filling the sealing cavity 431 has strong permeability. This gas will penetrate into the pump body 44's receiving cavity 441 and dissolve in the water in the detection pool 12 and storage tank 141 as the impeller 45 operates, causing a change in the water's pH value. By monitoring the pH value of the water in the storage tank 141 in real time, it is possible to further determine whether the shaft seal assembly 46 near the impeller 45 has leaked, thereby enabling the differentiation and identification of the sealing status of shaft seal assemblies 46 at different locations.

[0050] The above are all optional embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A long shaft submersible pump tightness detection device, characterized in that, include: The testing component (1) includes a stand (11), a testing pool (12), a pressurizing component (13), and a liquid injection component (14). The stand (11) is mounted on the testing pool (12), and a controller (15) is provided on the stand (11). The pressurizing component (13) is mounted on the stand (11), and the liquid injection component (14) is mounted on the testing pool (12). The pressurizing component (13) is used to inject gas medium into the sealing cavity for sealing test, and the liquid injection component (14) is used to provide liquid medium to the long-shaft submersible pump to simulate actual application and cooperate with the pressurizing component (13) to perform sealing test. The drive assembly (2) includes a first motor (21) and a transmission component (22). The transmission component (22) is disposed on one end of the shaft housing (43). The transmission component (22) is provided with a first output end and a second output end. The first motor (21) is connected to the transmission component (22) in a transmission connection. The first output end is connected to one end of the pump shaft (42). The first motor (21) is electrically connected to the controller (15). The load assembly (3) includes a piston cylinder (31), a load piston (32), and a load drive (33). One end of the piston cylinder (31) is connected to the second output end. The load piston (32) is slidably disposed inside the piston cylinder (31). The load drive (33) is disposed at one end of the piston cylinder (31) away from the transmission member (22). The load drive (33) is connected to the load piston (32). The load drive (33) is used to drive the load piston (32) to reciprocate within the piston cylinder (31), thereby causing the load piston (32) to cyclically apply impact loads to the pump shaft (42).

2. The long shaft submersible pump sealing detection device according to claim 1, characterized in that: The pressurizing component (13) includes an air pump (131), an air tank (132), and a pressure sensor (133). The air pump (131) and the air tank (132) are both fixed on the support frame (11). The air tank (132) is filled with ammonia. The air pump (131) is electrically connected to the controller (15). The input end of the air pump (131) is connected to the air tank (132), and the output end of the air pump (131) is connected to the sealing cavity. The pressure sensor (133) is installed on the shaft housing (43) and is electrically connected to the controller (15). The pressure sensor (133) can be used to monitor the pressure changes inside the sealing cavity in real time.

3. The long shaft submersible pump sealing detection device according to claim 2, characterized in that: The liquid injection component (14) includes a storage tank (141) and a pH sensor (142). The storage tank (141) is located on the outer wall of the detection pool (12). The detection pool (12) and the storage tank (141) are interconnected. Both the detection pool (12) and the storage tank (141) are filled with liquid medium. A drain pipe is provided on the pump body (44) and is connected to the storage tank (141). The pH sensor (142) is located inside the storage tank (141) and is electrically connected to the controller (15). The pH sensor (142) is used to monitor the pH value of the liquid medium in the storage tank (141).

4. The sealing performance testing device for a long-shaft submersible pump according to claim 3, characterized in that: The transmission component (22) includes a connecting shell (221), a transmission shaft (222), a driving bevel gear (223), and a driven bevel gear (224). The connecting shell (221) is located at the end of the shaft housing (43) away from the pump body (44). The transmission shaft (222) is rotatably mounted on the connecting shell (221). The first motor (21) is fixed on the connecting shell (221). The driving bevel gear (223) and the driven bevel gear (224) are located inside the connecting shell (221). The driving bevel gear (223) is fixed on the output end of the first motor (21). The driven bevel gear (224) is coaxially fixedly connected to the transmission shaft (222). The driving bevel gear (223) and the driven bevel gear (224) mesh. One end of the transmission shaft (222) is connected to the pump shaft (42), and the other end of the transmission shaft (222) is rotatably connected to one end of the piston cylinder (31).

5. The sealing performance testing device for a long-shaft submersible pump according to claim 4, characterized in that: The load drive component (33) includes a mounting housing (331), a second motor (332), a drive disc (333), and a pull rod (334). The piston cylinder (31) is fixed on the side of the connecting housing (221) away from the shaft housing (43). The mounting housing (331) is fixed on the end of the piston cylinder (31) away from the connecting housing (221). The second motor (332) is fixed on the mounting housing (331) and is electrically connected to the controller (15). The drive disc (333) is located on the mounting housing (331). Inside the housing (331), the drive disk (333) is fixedly connected to the output end of the second motor (332). A connecting shaft (3331) is fixedly mounted on the drive disk (333). The connecting shaft (3331) and the drive disk (333) are eccentrically arranged. One end of the pull rod (334) is rotatably connected to the connecting shaft (3331), and the other end of the pull rod (334) is rotatably connected to the load piston (32). The load piston (32), the pull rod (334), and the drive disk (333) combine to form a crank-slider mechanism.

6. The sealing performance testing device for a long-shaft submersible pump according to claim 5, characterized in that: An impact piston (34) is slidably disposed inside the piston cylinder (31). The impact piston (34) is located between the load piston (32) and the transmission shaft (222). A filling cavity (311) is disposed between the impact piston (34) and the load piston (32). An inert gas medium is disposed inside the filling cavity (311).

7. The sealing performance testing device for a long-shaft submersible pump according to claim 6, characterized in that: The mounting housing (331) is provided with an adjusting component (35) for adjusting the volume of the filling cavity (311). The adjusting component (35) includes a gas cylinder (351), an injection pipe (352), and a displacement driving component (353). The gas cylinder (351) is fixed on the support frame (11). The injection pipe (352) is slidably disposed in the mounting housing (331). An air inlet (321) is provided through the load piston (32). One end of the injection pipe (352) is movably inserted into the air inlet (321), and the other end of the injection pipe (352) is connected to the gas cylinder (351). The displacement driving component (353) is fixed on the mounting housing (331). The displacement drive (353) is electrically connected to the controller (15), and the output end of the displacement drive (353) is connected to the air injection pipe (352). The displacement drive (353) can drive the air injection pipe (352) to slide back and forth in the mounting shell (331). A first opening and closing element (36) is provided in the air inlet (321). The first opening and closing element (36) is used to actively block the air inlet (321). A second opening and closing element (37) is provided at one end of the air injection pipe (352) near the air inlet (321). The second opening and closing element (37) is used to control the amount of air injected into the air injection pipe, thereby controlling the volume of the filling cavity (311).

8. The sealing performance testing device for a long-shaft submersible pump according to claim 7, characterized in that: The first opening and closing component (36) includes a sealing plug (361) and a clamping spring (362). A support part (322) is fixedly provided on the side of the load piston (32) facing the impact piston (34). The support part (322) is mounted on the air inlet (321). A sliding rod (3611) is fixedly provided on the sealing plug (361). The sealing plug (361) is slidably disposed on the support part (322) through the sliding rod (3611). The sealing plug (361) is movably disposed in the air inlet (321). The clamping spring (362) is sleeved on the sliding rod (3611). One end of the clamping spring (362) is connected to the sealing plug (361), and the other end of the clamping spring (362) is connected to the support part (322).

9. The sealing performance testing device for a long-shaft submersible pump according to claim 8, characterized in that: The second opening / closing component (37) includes a stop plug (371) and a return spring (372). A support portion (3521) is fixed inside the air injection pipe (352). An extension rod (3711) is fixed on one side of the stop plug (371). The stop plug (371) is slidably disposed on the support portion (3521) via the extension rod (3711). An abutment portion (3712) is fixed on the side of the stop plug (371) facing away from the extension rod (3711). The abutment portion (3712) is slidably connected to the air injection pipe (352), and the end of the abutment portion (3712) facing away from the stop plug (371) is connected to the air injection pipe (352). The sealing plug (361) is in motion abutting, and the return spring (372) is sleeved on the extension rod (3711). One end of the return spring (372) is connected to the pressing plug (371), and the other end of the return spring (372) is connected to the bearing part (3521). The pressing plug (371) performs a movable sealing of the air injection pipe (352) under the action of the return spring (372). When the displacement drive (353) drives the air injection pipe (352) to be inserted into the air inlet (321), the air inlet (321) and the air injection pipe (352) are connected under the action of the abutting part (3712).

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