A kind of oil-submerged screw pump universal shaft test device
Patent Information
- Application Number
- CN202522324888.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-03
- Publication Date
- 2026-09-15
- Estimated Expiration
- 2035-11-03
AI Technical Summary
此万向轴为潜油直驱螺杆泵领域的公知产品，但对于万向轴的检测设备现在确实空白，如果万向轴使用寿命短不仅会导致螺杆泵运行不稳定还会加剧零件磨损，降低工作效率，增加维护成本，因此为了验证万向轴的使用工况，保证机组使用寿命，亟需根据万向轴的特性研究一种潜油螺杆泵万向轴试验装置及方法
[0015] The beneficial effects of this utility model are: it can effectively simulate the actual working conditions of the universal joint when it is working downhole, conduct type tests and fatigue tests on the universal joint, and ensure the service life of the universal joint.
Smart Images
Figure CN224758089U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a test device for the universal joint of a submersible screw pump, belonging to the technical field of oil production equipment. Background Technology
[0002] Submersible direct-drive screw pumps, with their high efficiency and energy saving, strong adaptability (especially suitable for high viscosity, high sand content, and gas-bearing oil wells) and low maintenance requirements, have broad prospects in heavy oil extraction, unconventional oil and gas development, and efficiency enhancement of old wells. With the intelligent and green transformation of oilfields, their direct-drive technology advantages will accelerate the replacement of traditional lift processes, becoming an important development direction for future artificial lift, with significant market potential.
[0003] A submersible direct-drive screw pump consists of a submersible motor, a protector, an inlet (containing a universal joint), a screw pump, a power cable, and a surface control cabinet. The motor and protector operate in concentric circular motion, while the screw pump rotor rotates on its own axis and also undergoes eccentric motion. Therefore, a universal joint is required between the protector and the screw pump. This universal joint must meet the following conditions: it must be able to rotate on its own axis, achieve eccentric motion, and transmit the large torque and axial pressure required during unit operation. While this universal joint is a well-known product in the submersible direct-drive screw pump field, there is currently a lack of testing equipment for it. A short service life for the universal joint not only leads to unstable operation of the screw pump but also accelerates component wear, reduces work efficiency, and increases maintenance costs. Therefore, to verify the operating conditions of the universal joint and ensure the service life of the unit, it is urgent to study a testing device and method for the universal joint of a submersible screw pump based on its characteristics. Utility Model Content
[0004] The purpose of this invention is to provide a testing device for the universal joint of a submersible screw pump, which can effectively simulate the actual working conditions of the universal joint when it is working downhole, conduct type tests and fatigue tests on the universal joint, ensure the service life of the universal joint, and solve the problems existing in the background technology.
[0005] The technical solution of this utility model is: A testing device for a universal joint of a submersible screw pump includes a top fixed plate, a hydraulic cylinder, steel balls, an upper bearing seat, an upper bearing assembly, a first connecting shaft, a second connecting shaft, a lower bearing assembly, and a fixed base. The top fixed plate and the fixed base are connected by a screw. The hydraulic cylinder, steel balls, upper bearing seat, first connecting shaft, universal joint under test, and second connecting shaft are arranged sequentially between the top fixed plate and the fixed base. The upper bearing assembly is installed on the upper part of the first connecting shaft and is located inside the upper bearing seat. An eccentric bearing is installed in the middle of the first connecting shaft, and its lower part is connected to one end of the universal joint under test. The other end of the universal joint under test is connected to the upper part of the second connecting shaft. A toothed pulley is installed in the middle of the second connecting shaft, and the toothed pulley is connected to the output shaft of a motor through a transmission toothed belt. The lower bearing assembly is installed on the lower part of the second connecting shaft and is located inside the fixed base.
[0006] The screw has a central fixing plate in its middle section, and an eccentric bearing is installed inside the central fixing plate. The central fixing plate has through holes at both ends and fixing holes on both sides, with the through holes and fixing holes connected and their center lines perpendicular to each other. The middle section of the screw consists of two smooth rods, each passing through the through holes at both ends of the central fixing plate. The position of the central fixing plate on the screw is adjustable vertically, and it is fixedly connected to the screw via set screws passing through the fixing holes. When the length of the universal joint being measured is different, the position of the central fixing plate on the screw can be adjusted according to the length of the universal joint being measured.
[0007] The screw has upper and lower threads at its top and bottom ends, respectively, and is threaded to the top fixing plate and the fixing base via the upper and lower threads. The length of the upper thread is greater than the length of the lower thread. The position of the top fixing plate on the screw is adjustable and locked in place by a nut. When the length of the universal joint being measured is different, the position of the top fixing plate on the screw is adjusted in conjunction with that of the middle fixing plate.
[0008] The upper bearing assembly consists of two upper and lower centering bearings and a middle thrust bearing, separated by a spacer. The centering bearings are deep groove ball bearings, used for radial centering of the universal joint and connecting shaft 1, while the thrust bearing bears the axial force transmitted from the hydraulic cylinder, ensuring that the axial force can be transmitted to the universal joint. The lower bearing assembly has the same structure as the upper bearing assembly, ensuring that the axial force can be applied to both ends of the universal joint.
[0009] The connecting shaft consists of optical shaft one, optical shaft two, and spline shaft one. Optical shaft one, optical shaft two, and spline shaft one are connected sequentially from top to bottom. Optical shaft one mates with the upper bearing assembly, and optical shaft two mates with the inner hole of the eccentric bearing. The distance between the center line of optical shaft one and the center line of spline shaft one of the connecting shaft is consistent with the eccentricity of the eccentric bearing. Optical shaft two has an L-shaped structure to facilitate the installation of the eccentric bearing. The eccentric bearing is set at the upper end of the L-shaped structure by a positioning device.
[0010] The second connecting shaft consists of a third optical shaft and a second spline shaft. The third optical shaft is equipped with a positioning platform, which divides the third optical shaft into two parts. The upper part of the third optical shaft is equipped with a toothed pulley, which is connected to the output shaft of the motor through a transmission toothed belt. The lower part of the third optical shaft is engaged with the lower bearing assembly. Both spline shaft one and spline shaft two are provided with male splines, which respectively mate with the female splines at both ends of the universal joint being tested. The two ends of the universal joint being tested are respectively connected to the lower part of the connecting shaft and the upper part of the connecting shaft two through the male splines and female splines.
[0011] The cylinder body of the hydraulic cylinder is connected to the top fixed plate. The bottom of the hydraulic cylinder rod is provided with an arc-shaped groove one, and the top of the upper bearing seat is provided with an arc-shaped groove two. Both the arc-shaped groove one and the arc-shaped groove two are matched with the shape of the steel ball. The upper and lower ends of the steel ball are respectively set in the arc-shaped groove one and the arc-shaped groove two.
[0012] The fixed base is installed on the test platform.
[0013] The hydraulic cylinder, steel balls, eccentric bearings, positioning devices, centering bearings, thrust bearings, spacers, toothed pulleys, and transmission toothed belts mentioned are all commonly known and used equipment in the field.
[0014] During testing, the universal joint under test is mounted on the test platform. Both ends of the universal joint are connected to connecting shaft one and connecting shaft two, respectively. An eccentric bearing is mounted on connecting shaft one, and connecting shaft two is connected to the motor's output shaft via a toothed pulley and a toothed belt. When the motor is started, the lower end of the universal joint under test moves concentrically with the toothed belt, while the upper end rotates and moves eccentrically with the eccentric bearing. Simultaneously, an axial force is applied to both ends of the universal joint under test by a top hydraulic cylinder. The test can be conducted by applying different axial forces and speeds to observe changes in the universal joint. After a period of continuous simulation, the universal joint is checked for deformation, damage, or bending. If no structural damage is found during internal dissection, it is considered a qualified product; otherwise, it is considered a defective product.
[0015] The beneficial effects of this utility model are: it can effectively simulate the actual working conditions of the universal joint when it is working downhole, conduct type tests and fatigue tests on the universal joint, and ensure the service life of the universal joint. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the upper bearing assembly structure of this utility model; Figure 3 This is a schematic diagram of the connecting shaft structure of this utility model; Figure 4 This is a schematic diagram of the connecting shaft two structure of this utility model; Figure 5 This is a schematic diagram of the eccentric bearing structure of this utility model; In the diagram: 1. Top fixing plate; 2. Oil cylinder; 3. Steel ball; 4. Upper bearing seat; 5. Upper bearing assembly; 5. Centering bearing; 5-1. Thrust bearing; 5-2. Spacer; 5-3. Eccentric bearing; 6. Middle fixing plate; 7. Connecting shaft 1; 8. Optical shaft 1; 8-1. Optical shaft 2; 8-2. Splined shaft 1; 8-3. Universal shaft under test; 9. Transmission toothed belt; 10. Connecting shaft 2; 11. Optical shaft 3; 11-1. Splined shaft 2; 11-2. Positioning table; 11-3. Lower bearing assembly; 12. Fixed base; 13. Detailed Implementation
[0017] The present invention will be further described below with reference to the accompanying drawings and examples.
[0018] A testing device for the universal joint of a submersible screw pump includes a top fixed plate 1, a cylinder 2, steel balls 3, an upper bearing seat 4, an upper bearing assembly 5, a first connecting shaft 8, a second connecting shaft 11, a lower bearing assembly 12, and a fixed base 13. The top fixed plate 1 and the fixed base 13 are connected by a screw. The cylinder 2, steel balls 3, upper bearing seat 4, first connecting shaft 8, the universal joint under test 9, and the second connecting shaft 11 are arranged sequentially between the top fixed plate 1 and the fixed base 13. The upper bearing assembly 5 is installed on the upper part of the first connecting shaft 8 and is located inside the upper bearing seat 4. An eccentric bearing 6 is installed in the middle of the first connecting shaft 8 and its lower part is connected to one end of the universal joint under test 9. The other end of the universal joint under test 9 is connected to the upper part of the second connecting shaft 11. A toothed pulley is installed in the middle of the second connecting shaft 11, and the toothed pulley is connected to the output shaft of a motor through a transmission toothed belt 10. The lower bearing assembly 12 is installed on the lower part of the second connecting shaft 11 and is located inside the fixed base 13.
[0019] The screw has a central fixing plate 7, and an eccentric bearing 6 is installed inside the central fixing plate 7. The central fixing plate 7 has through holes at both ends and fixing holes on both sides, with the through holes and fixing holes connected and their center lines perpendicular to each other. The screw has two smooth rods in the middle, each passing through the through holes at both ends of the central fixing plate 7. The position of the central fixing plate 7 on the screw is adjustable vertically, and it is fixedly connected to the screw via set screws passing through the fixing holes. When the length of the universal joint 9 being measured is different, the position of the central fixing plate 7 on the screw can be adjusted according to the length of the universal joint 9 being measured.
[0020] The screw has upper and lower threads at its top and bottom ends, respectively, and is threaded to the top fixing plate 1 and the fixing base 13 via the upper and lower threads. The length of the upper thread is greater than the length of the lower thread. The position of the top fixing plate 1 on the screw can be adjusted up and down and is locked in place by a nut. When the length of the universal joint 9 being measured is different, the position of the top fixing plate 1 on the screw is adjusted in conjunction with the position of the middle fixing plate 7.
[0021] The upper bearing assembly consists of two upper and lower centering bearings 5-1 and a middle thrust bearing 5-2, separated by a spacer 5-3. The centering bearings 5-1 are deep groove ball bearings, used for radial centering of the universal joint and connecting shaft 1, while the thrust bearing bears the axial force transmitted from the hydraulic cylinder, ensuring that the axial force can be transmitted to the universal joint. The lower bearing assembly has the same structure as the upper bearing assembly, ensuring that the axial force can be applied to both ends of the universal joint.
[0022] The connecting shaft 8 consists of optical shaft 8-1, optical shaft 8-2, and spline shaft 8-3. Optical shaft 8-1, optical shaft 8-2, and spline shaft 8-3 are connected sequentially from top to bottom. Optical shaft 8-1 mates with the upper bearing assembly 5, and optical shaft 8-2 mates with the inner hole of the eccentric bearing. The distance between the center lines of optical shaft 8-1 and spline shaft 8-3 of connecting shaft 8 is consistent with the eccentricity of the eccentric bearing 6. Optical shaft 8-2 has an L-shaped structure, which facilitates the installation of the eccentric bearing. The eccentric bearing is set at the upper end of the L-shaped structure by a positioning device.
[0023] The connecting shaft 2 11 is composed of optical shaft 3 11-1 and spline shaft 2 11-2. Optical shaft 3 11-1 is provided with a positioning platform 11-3. Optical shaft 3 11-1 is divided into two parts by the positioning platform 11-3. The upper part of optical shaft 3 11-1 is equipped with a toothed pulley. The toothed pulley is connected to the output shaft of the motor through the transmission toothed belt 10. The lower part of optical shaft 3 11-1 is engaged with the lower bearing assembly 12. Both spline shaft 1 8-3 and spline shaft 2 11-2 are provided with male splines, which are engaged with the female splines at both ends of the universal joint 9 being tested. The two ends of the universal joint 9 being tested are connected to the lower part of connecting shaft 1 8 and the upper part of connecting shaft 2 11 through male splines and female splines, respectively.
[0024] The cylinder body of the hydraulic cylinder 2 is connected to the top fixing plate 1. The bottom of the hydraulic cylinder rod of the hydraulic cylinder 2 is provided with an arc groove 1, and the top of the upper bearing seat 4 is provided with an arc groove 2. Both the arc groove 1 and the arc groove 2 are matched with the shape of the steel ball 3. The upper and lower ends of the steel ball 3 are respectively set in the arc groove 1 and the arc groove 2.
[0025] The fixed base 13 is installed on the test platform.
[0026] During testing, the universal joint 9 to be tested is installed on the test platform. Both ends of the universal joint 9 are connected to connecting shaft 1 (8) and connecting shaft 2 (11) respectively. An eccentric bearing 6 is installed on connecting shaft 1 (8), and connecting shaft 2 (11) is connected to the output shaft of the motor via a toothed pulley and a toothed belt 10. When the motor is started, the lower end of the universal joint 9 moves concentrically with the toothed belt 10, while the upper end rotates and moves eccentrically with the eccentric bearing 6. Simultaneously, the top cylinder applies axial force to both ends of the universal joint 9, thus testing it. The changes in the universal joint 9 can be observed by applying different axial forces and speeds. After a period of continuous simulation, the universal joint 9 is checked for deformation, damage, or bending. If no structural damage is found during internal dissection, it is considered a qualified product; otherwise, it is considered a defective product.
[0027] In this embodiment, refer to the appendix. Figure 1-5A testing device for the universal joint of a submersible screw pump includes a top fixed plate 1, a cylinder 2, steel balls 3, an upper bearing seat 4, an upper bearing assembly 5, a connecting shaft 1 8, a universal joint under test 9, a connecting shaft 2 11, a lower bearing assembly 12, and a fixed base 13. The universal joint under test 9 has female splines at both ends. One end of the connecting shaft 1 8 is connected to the upper bearing assembly 5, and the other end is a male spline connected to the female spline of the universal joint under test 9. An eccentric bearing is connected in the middle of the connecting shaft 1 8 to ensure the eccentric movement of the universal joint under test. A toothed pulley is connected to the connecting shaft 2 11, and the toothed pulley is connected to the output shaft of the motor through a transmission toothed belt 10 to provide power and test torque for the unit operation.
[0028] The motor is started, and the motor drives the toothed pulley to rotate. The toothed pulley and the second connecting shaft 11 are connected by a key, and the power is transmitted to the second connecting shaft 11. The second connecting shaft 11 drives the universal shaft 9 under test to rotate. Both ends of the universal shaft 9 under test can deflect at a certain angle. When rotating, the bottom of the universal shaft 9 under test and the second connecting shaft 11 move concentrically. The upper end of the universal shaft 9 under test is connected to the first connecting shaft 8, which swings back and forth with the eccentric bearing 6, and performs eccentric motion. The rotational speed of the toothed pulley is 0-500 rpm, which covers the speed range of the unit operation.
[0029] When hydraulic cylinder 2 is activated, its cylinder rod extends downwards, applying axial force. This axial force is transmitted to the upper bearing assembly via steel balls. The steel balls ensure that the axial force is still transmitted downwards even when the universal joint being tested is moving eccentrically with the upper bearing assembly. The upper bearing assembly consists of two upper and lower centering bearings 5-1 and a middle thrust bearing 5-2, separated by a spacer 5-3. The centering bearings 5-1 are deep groove ball bearings, providing radial centering for the universal joint being tested and the connecting shaft 1. The thrust bearing bears the axial force transmitted from the hydraulic cylinder, ensuring that the axial force is transmitted to the universal joint being tested. The lower bearing assembly has the same structure as the upper bearing assembly, ensuring that the axial force can be applied to both ends of the universal joint being tested.
[0030] During the test, the lower end of the universal shaft 9 under test moves concentrically with the toothed pulley, while the upper end of the universal shaft under test rotates and moves eccentrically with the eccentric bearing 6. At the same time, the top cylinder applies axial force to both ends of the universal shaft under test to test the universal shaft under test. The changes of the universal shaft under test can be observed by applying different axial forces and speeds.
[0031] The eccentric bearing is model 6: 524806K, with an inner diameter of φ30mm, an outer diameter of φ110mm, a thickness of 35mm, an eccentricity of 20mm, and a keyway of 10mm. The eccentricity of a typical screw pump is 4-10mm, but the universal joint designed in this invention can achieve an eccentricity of 0-20mm, meeting the usage requirements of screw pumps.
[0032] The universal joint under test has two universal joints and can deflect 20mm, which meets the usage requirements.
[0033] The experimental procedure for this invention is as follows: A pressure of 20T is set, and the hydraulic cylinder pushes downwards to apply 20T of pressure to the universal joint under test. The motor start button is pressed, and the motor rotates clockwise at 300 rpm. The universal joint under test rotates clockwise along with the motor. Simultaneously, the upper and lower ends of the universal joint under test tilt at a certain angle, performing eccentric motion with the eccentric bearing. The motor's control panel can display the applied pressure and speed in real time.
[0034] The purpose of this invention is to simulate the actual operating conditions of a universal joint in an underground well and conduct a type test. The simulation needs to be conducted continuously for six months, after which the universal joint under test should be inspected for deformation, damage, bending, or other changes. Internally, it needs to be dissected to observe for structural damage. If no such problems are found, the universal joint is considered to have passed the test and can be used.
Claims
1. A device for testing a universal shaft of a submersible screw pump, characterized in that: The device includes a top fixing plate (1), a hydraulic cylinder (2), steel balls (3), an upper bearing seat (4), an upper bearing assembly (5), a connecting shaft one (8), a connecting shaft two (11), a lower bearing assembly (12), and a fixed base (13). The top fixing plate (1) and the fixed base (13) are connected by screws. The hydraulic cylinder (2), steel balls (3), upper bearing seat (4), connecting shaft one (8), the universal joint to be measured (9), and connecting shaft two (11) are arranged sequentially between the top fixing plate (1) and the fixed base (13). The upper bearing assembly (5) is installed on the upper part of the connecting shaft (8) and is located inside the upper bearing seat (4); the eccentric bearing (6) is installed in the middle of the connecting shaft (8) and the lower part is connected to one end of the universal shaft (9) being measured; the other end of the universal shaft (9) being measured is connected to the upper part of the connecting shaft (11), the toothed pulley is installed in the middle of the connecting shaft (11), the toothed pulley is connected to the output shaft of the motor through the transmission toothed belt (10), and the lower bearing assembly (12) is installed on the lower part of the connecting shaft (11) and is located inside the fixed base (13).
2. The test device for the universal shaft of the submersible screw pump according to claim 1, characterized in that: The screw has a central fixing plate (7) in the middle, and an eccentric bearing (6) is set inside the central fixing plate (7). The central fixing plate (7) has through holes at both ends and fixing holes on both sides. The through holes and fixing holes are connected and their center lines are perpendicular to each other. The screw has two smooth rods in the middle. The two screws pass through the through holes at both ends of the central fixing plate (7). The position of the central fixing plate (7) on the screw can be adjusted up and down, and it is fixedly connected to the screw through the fixing hole by a set screw.
3. The universal joint testing device for a submersible screw pump according to claim 2, characterized in that: The upper and lower ends of the screw are respectively provided with upper threads and lower threads. The screw is threaded to the top fixing plate (1) and the fixing base (13) through the upper threads and lower threads respectively. The length of the upper thread is greater than the length of the lower thread. The position of the top fixing plate (1) on the screw can be adjusted up and down and locked by a nut.
4. A test device for the universal joint of a submersible screw pump according to claim 1 or 2, characterized in that: The upper bearing assembly consists of two upper and lower centering bearings (5-1) and a middle thrust bearing (5-2), with the centering bearing (5-1) and the thrust bearing (5-2) separated by a spacer (5-3).
5. A test device for the universal joint of a submersible screw pump according to claim 1 or 2, characterized in that: The connecting shaft one (8) is composed of optical shaft one (8-1), optical shaft two (8-2) and spline shaft one (8-3). Optical shaft one (8-1), optical shaft two (8-2) and spline shaft one (8-3) are connected from top to bottom. Optical shaft one (8-1) is matched with the upper bearing assembly (5), and optical shaft two (8-2) is matched with the inner hole of the eccentric bearing. The distance between the center line of optical shaft one (8-1) and spline shaft one (8-3) of connecting shaft one (8) is consistent with the eccentricity of the eccentric bearing (6). Optical shaft two (8-2) has an L-shaped structure.
6. The universal joint testing device for a submersible screw pump according to claim 5, characterized in that: The connecting shaft 2 (11) is composed of optical shaft 3 (11-1) and spline shaft 2 (11-2). Optical shaft 3 (11-1) is provided with a positioning platform (11-3). Optical shaft 3 (11-1) is divided into two parts by the positioning platform (11-3). The upper part of optical shaft 3 (11-1) is equipped with a toothed pulley. The toothed pulley is connected to the output shaft of the motor through the transmission toothed belt (10). The lower part of optical shaft 3 (11-1) is engaged with the lower bearing assembly (12).
7. The universal joint testing device for a submersible screw pump according to claim 6, characterized in that: Both the first spline shaft (8-3) and the second spline shaft (11-2) are provided with male splines, which respectively cooperate with the female splines at both ends of the universal shaft (9) under test. The two ends of the universal shaft (9) under test are respectively connected to the lower part of the first connecting shaft (8) and the upper part of the second connecting shaft (11) through the male splines and female splines.
8. A test device for the universal joint of a submersible screw pump according to claim 1 or 2, characterized in that: The cylinder body of the oil cylinder (2) is connected to the top fixing plate (1). The bottom of the oil cylinder rod of the oil cylinder (2) is provided with an arc groove one, and the top of the upper bearing seat (4) is provided with an arc groove two. Both the arc groove one and the arc groove two match the shape of the steel ball (3). The upper and lower ends of the steel ball (3) are respectively set in the arc groove one and the arc groove two.