Bearing experiment device, bearing electric breakdown experiment method and bearing electric corrosion experiment method

Abstract

The invention discloses a bearing experiment device, a bearing electric breakdown experiment method and a bearing electric corrosion experiment method, and the experiment device comprises a bearing experiment mechanical mechanism which is provided with a bearing sample; the torque loading mechanism is used for applying torque to the bearing sample and checking the torque and the rotating speed of the bearing sample; the load conversion mechanism is used for converting the torque applied by the torque loading mechanism into axial force on the bearing sample; the power mechanism is used for providing power for rotation of the bearing sample; the oil supply mechanism is used for forming an oil film layer on the bearing sample; the voltage loading mechanism is used for applying adjustable voltage to the bearing sample and monitoring the change of voltage and current flowing through the bearing sample in real time; and the data acquisition mechanism is used for acquiring experimental data. The experimental device disclosed by the invention can accurately simulate the actual operation condition of the bearing under the oil lubrication condition in a generator gearbox integrated system, and realizes accurate electric breakdown and electric corrosion experiments on a bearing sample of a tapered roller bearing type.

Description

Technical Field

[0001] This invention belongs to the technical field of bearing testing equipment, specifically a bearing testing device, a bearing electrical breakdown test method, and a bearing electrical erosion test method. Background Technology

[0002] As wind turbines develop towards deep-sea and high-power applications, the reliability requirements for wind turbines are becoming increasingly stringent. Semi-direct-drive wind turbine generator gearbox integrated systems have advantages such as high power density, high efficiency, and high reliability, and have become the mainstream technology route for offshore wind turbines. Currently, the problem of electrolytic corrosion damage to bearings and gears in generator gearbox integrated systems has been a technical challenge that has hindered the development of the industry.

[0003] In a generator gearbox integrated system, the generator is directly mounted on the gearbox shaft. Since there are no bearings at the generator end, the shaft voltage mainly affects the bearings and gears inside the gearbox, especially the tapered roller bearings on the gearbox shaft and the gears near the generator end. When the shaft voltage exceeds the oil film breakdown threshold between the bearings or gears, it will cause electrolytic erosion damage to the bearings and gears, which will lead to performance degradation or even failure of the generator gearbox integrated system, resulting in huge losses.

[0004] To elucidate the failure mechanisms of electrical breakdown and electro-erosion (EDS) and to seek practical and effective solutions to prevent EDS, theoretically, EDS tests could be conducted on the entire generator gearbox integrated system. However, due to limitations in experimental conditions and costs, directly using a prototype of the entire generator gearbox integrated system for testing is too expensive and not universally applicable. But conducting separate EDS tests on the bearings and gears within the generator gearbox integrated system can reduce experimental costs.

[0005] In existing generator gearbox integrated systems, the bearings most affected by shaft voltage are the tapered roller bearings on the gearbox shaft. Currently, the tapered roller bearings in generator gearbox integrated systems are lubricated with oil, and the force they are subjected to is mainly axial force. However, the bearing electro-erosion testing equipment currently used in the industry is mainly designed for cylindrical roller bearings in generators, using grease for lubrication and radial loading. This is far from the actual operating conditions of the tapered roller bearings in generator gearbox integrated systems and cannot simulate the actual operating conditions of the tapered roller bearings in generator gearbox integrated systems. Therefore, it is also impossible to conduct accurate electrical breakdown and electro-erosion tests on tapered roller bearings. Summary of the Invention

[0006] The purpose of this invention is to provide a bearing testing apparatus, a bearing electrical breakdown testing method, and a bearing electrical erosion testing method, so as to solve at least one aspect of the problems and defects mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A bearing testing apparatus, comprising:

[0009] A bearing testing mechanism includes a mounting box and a bearing assembly; the mounting box has a mounting cavity, and the bearing assembly is detachably installed in the mounting cavity; the bearing assembly includes a rotating shaft and a bearing sample detachably installed on the rotating shaft, the rotating shaft having a first shaft end and a second shaft end, and the bearing sample being a tapered roller bearing;

[0010] A torque loading mechanism, insulated from the second end of the shaft, is used to apply an adjustable torque to the bearing sample;

[0011] A load conversion mechanism, installed on the first end of the shaft, is used to convert the torque applied by the torque loading mechanism into an axial force on the bearing sample, and to monitor the torque and rotational speed of the bearing sample.

[0012] A power mechanism, insulated from the load conversion mechanism, is used to drive the bearing assembly to rotate;

[0013] An oil supply mechanism, connected to the mounting cavity, is used to supply lubricating oil to the bearing sample;

[0014] A voltage loading mechanism, electrically connected to the bearing assembly, is used to apply an adjustable voltage to the bearing sample and monitor the current flowing through the bearing sample; and

[0015] The data acquisition mechanism is electrically connected to the torque loading mechanism and the voltage loading mechanism, and is used to acquire experimental data.

[0016] The bearing testing apparatus of this invention has a simple structure and is easy to operate. By setting up a bearing testing mechanical mechanism that enables the replacement of bearing samples, a torque loading mechanism that applies torque to the bearing samples, a load conversion mechanism that converts the torque applied to the bearing samples by the torque loading mechanism into the axial force of the bearing samples, a power mechanism that drives the bearing samples to rotate, an oil supply mechanism that enables the formation of an oil film layer on the bearing samples, a voltage loading mechanism that applies voltage to the bearing samples, and a data acquisition mechanism that collects experimental data, it can accurately simulate the actual operating conditions of tapered roller bearings under oil lubrication conditions in a generator gear integrated system. Thus, it can perform high-precision electrical breakdown tests on tapered roller bearing samples under oil lubrication conditions.

[0017] In one embodiment of this application, the number of bearing samples is two, and the two bearing samples are arranged in an O-shape on the rotating shaft.

[0018] In one embodiment of this application, the mounting box includes a main body, a first cover, and a second cover; the mounting cavity is formed inside the main body, and the main body has openings on both sides. The main body includes a detachably connected upper half and a lower half, which enclose the mounting cavity; both the first cover and the second cover are detachably mounted on the main body and respectively seal the openings on both sides of the main body; the first end and the second end of the shaft pass through the first cover and the second cover, respectively.

[0019] In one embodiment of this application, the mounting cavity has a first cavity, a second cavity, and a third cavity located between the first cavity and the second cavity. The bearing sample is located in the third cavity. The main housing is provided with an oil inlet, an oil outlet, an oil reservoir, and an intermediate hole. The oil reservoir is located at the bottom of the second cavity. The oil inlet, the intermediate hole, and the oil outlet are all located within the main housing. The oil inlet and the intermediate hole are located above and below the mounting cavity, respectively. The oil inlet connects the oil outlet of the oil supply mechanism and the mounting cavity. The intermediate hole extends along the axial direction of the rotating shaft, and its two ends connect the first cavity and the oil reservoir, respectively. The oil outlet connects to the oil reservoir.

[0020] In one embodiment of this application, the number of intermediate holes is at least two, and the intermediate holes are arranged sequentially at intervals along a horizontal direction perpendicular to the axis of rotation.

[0021] In one embodiment of this application, both the oil drain hole and the oil storage tank extend straight in the horizontal direction. The wall of the oil storage tank is arc-shaped and is coaxially arranged with the oil drain hole. The diameter of the wall of the oil storage tank is equal to the diameter of the oil drain hole.

[0022] In one embodiment of this application, a first oblique spline is provided on the first end of the shaft, and the load conversion mechanism includes a support seat, a support bearing, and a sleeve. The top end of the support seat is provided with a support cavity, and the sleeve has a first sleeve end and a second sleeve end. The first sleeve end is sleeved outside the first end of the shaft, and a second oblique spline matching the first oblique spline is provided on the inner wall of the first sleeve end; the second sleeve end is inserted into the support cavity; and the support bearing is fixed inside the support cavity and sleeved outside the second sleeve end.

[0023] In one embodiment of this application, the torque loading mechanism includes a magnetic powder brake, a brake coupling, a torque and speed sensor, a torque measuring insulated coupling, and a brake controller; the magnetic powder brake is connected to the torque and speed sensor via the brake coupling; the torque and speed sensor is connected to the second end of the shaft via the torque measuring insulated coupling; both the torque and speed sensor and the magnetic powder brake are electrically connected to a data acquisition mechanism; and the brake controller is electrically connected to the magnetic powder brake.

[0024] In one embodiment of this application, a vibration sensor electrically connected to the data acquisition mechanism is further included, the vibration sensor being used to measure the vibration of the bearing sample.

[0025] A method for testing bearing shaft current breakdown and electrical erosion includes the following steps:

[0026] S10. Provide the bearing test apparatus as described above, and perform pre-experiment preparation work on the test apparatus.

[0027] S20. Start the oil supply mechanism to lubricate the bearing sample;

[0028] S30. Determine the working parameters for the electrical breakdown test. The working parameters include the bearing sample rotation speed, bearing sample torque, and the frequency and magnitude of the simulated voltage applied to the bearing sample. Based on the working parameters, start and adjust the power mechanism, the torque loading mechanism, and the voltage loading mechanism for a specified time. Then, while keeping the frequency and magnitude of the simulated voltage, the bearing sample rotation speed, and the bearing sample torque constant, gradually increase the simulated voltage and monitor the change in current flowing through the bearing sample. Each increase in simulated voltage is also maintained for a specified time. When a sudden increase in current is detected, stop the experiment. Record the experimental data during the experiment.

[0029] S40. Replace the bearing sample and repeat steps S20 and S30 continuously. The replaced bearing sample is adjusted according to the electrical breakdown test working parameters in the experiment according to the electrical breakdown test plan.

[0030] S50. Based on the recorded experimental data, calculate the minimum oil film thickness value of the bearing sample when it is electrically broken down under different electrical breakdown test operating parameters, and mark the minimum breakdown voltage of the bearing sample under different electrical breakdown test operating parameters.

[0031] The bearing electrical breakdown test method of the present invention, by employing the above-mentioned bearing test apparatus, can perform high-precision electrical breakdown tests on tapered roller bearing samples under oil lubrication conditions, thereby significantly improving the reliability of electrical breakdown test data.

[0032] A bearing electro-erosion test includes the following steps:

[0033] S10. Provide the bearing test apparatus with vibration sensor as described above, and perform pre-experiment preparation work on the bearing test apparatus.

[0034] S20. Determine the working parameters of the bearing sample electro-erosion test. The working parameters of the electro-erosion test include the bearing sample rotation speed, bearing sample torque and the frequency of the simulated voltage applied to the bearing sample. Based on the determined working parameters of the electro-erosion test and the experimental results obtained by the bearing electrical breakdown test method as described above, determine the minimum breakdown voltage of the bearing sample. Set the magnitude of the simulated voltage based on the minimum breakdown voltage.

[0035] S30. Start the oil supply mechanism to lubricate the bearing sample;

[0036] S40. Start the power mechanism, the voltage loading mechanism and the torque loading mechanism. According to the working parameters of the electro-erosion experiment and the magnitude of the simulated voltage determined in step S20, adjust the torque and speed of the bearing sample, as well as the magnitude and frequency of the simulated voltage applied to the bearing sample. Keep the working parameters of the electro-erosion experiment unchanged and continue the experiment. Monitor the vibration changes of the bearing sample in real time through the vibration sensor. When a sudden increase in vibration is detected, stop the experiment, observe the macro- and micro-morphology of the surface of the bearing sample after the experiment, and record the relevant experimental data.

[0037] S50. Replace the bearing sample and repeat steps S20 to S40 continuously. After replacement, adjust the working parameters of the electro-erosion test according to the electro-erosion test plan during the experiment.

[0038] S60. Analyze the experimental data.

[0039] The bearing electrical breakdown test method of the present invention, by using the above-mentioned bearing test device with vibration sensor, can perform high-precision electrical erosion test on bearing samples of tapered roller bearing type under oil lubrication conditions, thereby significantly improving the reliability of electrical erosion test data. Attached Figure Description

[0040] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0041] Figure 1 This is a three-dimensional structural schematic diagram of a bearing experimental apparatus according to an embodiment of this application;

[0042] Figure 2 This is a three-dimensional structural schematic diagram of a bearing testing mechanical mechanism according to an embodiment of this application;

[0043] Figure 3 This is a schematic diagram of the exploded disassembly structure of a bearing experimental mechanical mechanism according to an embodiment of this application;

[0044] Figure 4 This is a cross-sectional view of the mounting box according to an embodiment of this application;

[0045] Figure 5 This is an exploded exploded structural diagram of an assembly consisting of a rotating shaft and a load conversion mechanism, as shown in an embodiment of this application.

[0046] Figure 6 This is a three-dimensional structural diagram of an assembly consisting of a bearing testing mechanical mechanism, a voltage loading mechanism, and an oil supply mechanism, as shown in an embodiment of this application.

[0047] Figure 7 This is a three-dimensional structural schematic diagram of a bearing experimental apparatus according to another embodiment of this application.

[0048] Figure label:

[0049] 10. Bearing testing mechanism; 11. Mounting box; 111. Main box; 111a. Upper half of the box; 111b. Lower half of the box; 1111. Oil inlet; 1112. Oil reservoir; 1113. Intermediate hole; 1114. Oil drain hole; 112. First cover; 113. Second cover; 114. Mounting cavity; 1141. First cavity; 1142. Second cavity; 1143. Third cavity; 12. Shaft; 121. First end of the shaft; 122. Second end of the shaft; 123. First oblique spline; 124. Boss; 13. Bearing sample; 14. Locking ring; 15. Spacer;

[0050] 20. Torque loading mechanism; 21. Magnetic powder brake; 22. Brake coupling; 23. Torque-speed sensor; 24. Torque measuring insulated coupling; 25. Brake controller; 26. Water cooler;

[0051] 30. Load conversion mechanism; 31. Support base; 32. Support bearing; 33. Sleeve; 331. First end of sleeve; 332. Second end of sleeve; 333. Second oblique spline;

[0052] 40. Power mechanism; 41. Adjustable speed motor; 42. Power insulated coupling;

[0053] 50. Voltage loading mechanism; 51. Signal generator; 52. Power amplifier; 53. First wire; 54. Bracket; 55. Carbon brush; 56. Second wire;

[0054] 60. Oil supply mechanism; 61. Oil tank; 62. Oil inlet pipe; 63. Oil outlet pipe; 641. Oil inlet pump; 642. Oil outlet pump; 65. Oil pressure measurement module; 66. Heat exchanger; 67. Oil inlet temperature sensor; 68. Oil outlet temperature sensor;

[0055] 71. Torque and speed information acquisition and display; 72. Digital oscilloscope; 73. Temperature acquisition and display;

[0056] 80. Insulating base;

[0057] 90. Vibration sensor. Detailed Implementation

[0058] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0059] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0060] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0061] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0062] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0063] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0064] Please see Figures 1 to 6 This is an embodiment of the bearing testing apparatus for electrical breakdown testing, as shown in this invention. Figure 1 As shown, the bearing experimental device includes a bearing experimental mechanical mechanism 10, a torque loading mechanism 20, a load conversion mechanism 30, a power mechanism 40, a voltage loading mechanism 50, an oil supply mechanism 60, and a data acquisition mechanism.

[0065] like Figure 2 and Figure 3 As shown, the bearing testing mechanism 10 includes a mounting box 11 and a bearing assembly. The mounting box 11 has a mounting cavity 114, within which the bearing assembly is detachably mounted and insulated from the mounting cavity 11. The bearing assembly includes a rotating shaft 12 detachably mounted on the mounting box 11 and a bearing specimen 13 detachably mounted on the rotating shaft 12. The rotating shaft 12 has a first shaft end 121 and a second shaft end 122. The bearing specimen 13 is a tapered roller bearing. A torque loading mechanism 20 is insulated from the second shaft end 122 and is used to apply an adjustable torque to the bearing specimen 13 and monitor the torque and speed of the bearing specimen 13 in real time. A load conversion mechanism 30 is mounted on the first shaft end 121 and is used to convert the torque applied by the torque loading mechanism 20 into an axial force on the bearing specimen 13, and monitor the torque and speed of the bearing specimen 13 in real time. Because the bearing specimen 13 mainly bears axial force during rotation, the axial force borne by the bearing specimen 13... Axial force is an important factor affecting electrolytic corrosion. By changing the torque applied to the bearing sample 13 by the torque loading mechanism 20, the axial force borne by the bearing sample 13 can be changed. The power mechanism 40 is insulated from the load conversion mechanism 30 and is used to provide power for the rotation of the bearing sample 13. The oil supply mechanism 60 is connected to the mounting cavity 114 and is used to supply lubricating oil to the bearing sample 13 so that an oil film layer is formed on the surface of the rollers of the bearing sample 13 in contact with the inner ring and the surface of the rollers in contact with the outer ring. The voltage loading mechanism 50 is electrically connected to the rotating shaft 12 and the mounting box 11 and is used to apply an adjustable voltage to the bearing sample 13 and monitor the current change flowing through the bearing sample 13 in real time. The data acquisition mechanism is electrically connected to the torque loading mechanism 20 and the voltage loading mechanism 50 and is used to collect experimental data, including the bearing sample rotation speed, bearing sample torque, the magnitude and frequency of the voltage applied to the bearing sample, and the current flowing through the bearing sample.

[0066] It should be noted that since the power mechanism 40 is insulated from the load conversion mechanism 30 and the torque loading mechanism 20 is insulated from the second end 122 of the shaft, when the voltage loading mechanism 50 applies voltage to the bearing sample 13, it can promote the formation of a closed experimental circuit of voltage loading mechanism 50 → bearing assembly → mounting box 11 → voltage loading mechanism 50. During the electrical breakdown test, lubricating oil is first supplied to the bearing sample 13 through the oil supply mechanism 60, so that an oil film layer is formed on the contact surface between the roller and the inner ring and the contact surface between the roller and the outer ring of the bearing sample 13. Then, the power mechanism 40 is started to drive the bearing sample 13 to rotate. Subsequently, the voltage loading mechanism 50 and the torque loading mechanism 20 are started to apply a specified voltage and a specified torque to the bearing sample 13. During the experiment, the voltage loading mechanism 50 can monitor the current flowing through the bearing sample 13, and the torque loading mechanism 20 can monitor the torque and speed of the bearing sample 13. The data acquisition mechanism collects the experimental data, and the experimenters organize the collected experimental data into a bearing electrical breakdown test data table. According to the bearing electrical breakdown test data table, the minimum breakdown voltage of the bearing sample 13 of the same specification tapered roller bearing type under different torque, voltage frequency, and speed is obtained.

[0067] Because the tapered roller bearings in real-world generator gearbox integrated systems are lubricated by oil, and the load they bear is mainly axial force, the bearing testing device of this application, by setting up a bearing testing mechanical mechanism 10 that enables the replacement of bearing sample 13, a torque loading mechanism 20 that applies torque to bearing sample 13, a load conversion mechanism 30 that converts the torque applied by the torque loading mechanism 20 into an axial force on the bearing, a power mechanism 40 that drives the bearing sample 13 to rotate, an oil supply mechanism 60 that enables the bearing sample 13 to form an oil film layer, a voltage loading mechanism 50 that applies voltage to bearing sample 13, and a data acquisition mechanism that collects experimental data, can accurately simulate the actual operating conditions of tapered roller bearings under oil lubrication conditions in generator gear integrated systems. Thus, it is possible to conduct high-precision electrical breakdown tests on tapered roller bearing type bearing samples under oil lubrication conditions.

[0068] In one embodiment of this application, such as Figure 3As shown, the mounting box 11 includes a main body 111, a first cover 112, and a second cover 113. An mounting cavity 114 is formed inside the main body 111. The main body 111 has open sides. The main body 111 includes a detachably connected upper half 111a and a lower half 111b. The upper half 111a and lower half 111b are preferably detachably connected by bolts. The upper half 111a and lower half 111b form the mounting cavity 114. Alternatively, the semi-circular cavity of the upper half 111a and the semi-circular cavity of the lower half 111b can be understood as forming the mounting cavity 114. The first cover 112 and the second cover 113 are both detachably mounted on the main body 111 and respectively seal the open sides of the main body 111 to close the mounting cavity 114. The first end 121 and the second end 122 of the shaft pass through the first cover 112 and the second cover 113, respectively. The structure of the mounting box 11 facilitates the installation and removal of the bearing assembly, thereby facilitating the replacement of the bearing sample 13 during experiments. To install the entire bearing assembly onto the mounting box 11, first remove the first cover 112 and the second cover 113 from the main housing 111, then remove the upper housing 111a from the lower housing 111b. Next, place the bearing assembly into the semi-circular cavity of the lower housing 111b. After placement, install the upper housing 111a onto the lower housing 111b to form the main housing 111. Then, install the first cover 112 and the second cover 113 onto the main housing 111 to complete the installation of the bearing assembly onto the mounting box 11. To remove the bearing assembly from the mounting box 11, simply follow the reverse procedure of installing the bearing assembly onto the mounting box.

[0069] Optional, such as Figure 4As shown, the mounting cavity 114 has a first cavity 1141, a second cavity 1142, and a third cavity 1143 located between the first cavity 1141 and the second cavity 1142. The bearing sample 13 is located in the third cavity 1143. The main housing 111 is provided with an oil inlet 1111, an oil outlet 1114, an oil reservoir 1112, and an intermediate hole 1113. The oil reservoir 1112 is located at the bottom of the second cavity 1142. When lubricating oil enters the second cavity 1142, it will automatically flow into the oil reservoir 1112. The oil inlet 1111, the intermediate hole 1113, and the oil outlet 1114 are all located inside the main housing 111. The oil inlet 1111 and the intermediate hole 1113 are located above and below the mounting cavity 114, respectively, for oil inlet. The hole 1111 connects the oil outlet end of the oil supply mechanism 60 and the mounting cavity 114, so that the oil supply mechanism 60 can send lubricating oil into the mounting cavity 114 through the oil inlet hole 1111 and drip it onto the bearing sample 13, so that an oil film layer is formed on the surface of the roller of the bearing sample 13 that contacts the inner ring and the surface of the roller that contacts the outer ring; the intermediate hole 1113 extends along the axial direction of the rotating shaft 12, and the two ends of the intermediate hole 1113 are respectively connected to the first cavity 1141 and the oil storage tank 1112, so that the lubricating oil that falls into the first cavity 1141 can flow into the oil storage tank 1112 through the intermediate hole 1113; the oil drain hole 1114 is connected to the oil storage tank 1112 and is used to return the lubricating oil in the oil storage tank 1112 to the oil supply mechanism 60. The oil inlet hole 1111, oil outlet hole 1114, oil reservoir 1112 and intermediate hole 1113 are designed to ensure that the lubricating oil that does not adhere to the bearing sample 13 can be well discharged back to the oil supply mechanism 60 while ensuring the lubrication of the bearing sample 13.

[0070] Furthermore, to ensure that the lubricating oil falling into the second cavity 1142 can be quickly discharged into the oil reservoir 1112, at least two intermediate holes 1113 are provided, and the intermediate holes 1113 are arranged sequentially at intervals along a horizontal direction perpendicular to the axis of the rotating shaft 12. For example, as... Figure 3 As shown, there are three intermediate holes 1113, which are arranged sequentially at intervals along a horizontal direction perpendicular to the axis of the rotating shaft 12.

[0071] Furthermore, to facilitate the machining of the oil storage tank 1112 and the oil drain hole 1114, both the oil drain hole 1114 and the oil storage tank 1112 extend straight in the horizontal direction. The tank wall of the oil storage tank 1112 is arc-shaped and is set coaxially with the oil drain hole 1114. The diameter of the tank wall of the oil storage tank 1112 is equal to the diameter of the oil drain hole 1114. In this way, during machining, the oil drain hole 1114 and the oil storage tank 1112 can be machined into shape in one go using a single drill bit.

[0072] In one embodiment of this application, in order to ensure the force balance of the bearing, there are two bearing samples 13. The two bearing samples 13 are arranged in an X-shape or an O-shape on the rotating shaft, and the two bearing samples 13 are separated by a spacer 15. The two bearing samples 13 and the spacer 15 form a bearing assembly structure. A boss 124 is provided on the rotating shaft 12 corresponding to the bearing assembly structure. The outer diameter of the boss 124 is smaller than the outer diameter of the inner ring of the bearing sample 13, but larger than the inner diameter of the inner ring of the bearing sample 13. The bearing assembly structure is clamped and locked on the rotating shaft 12 by the locking ring 14 sleeved on the rotating shaft 12 in conjunction with the boss 124.

[0073] In one embodiment of this application, such as Figure 1 As shown, the power mechanism 40 includes an adjustable speed motor 41 and a power insulated coupling 42. The adjustable speed motor 41 is connected to the second end 332 of the sleeve 33 of the load conversion mechanism 30 through the power insulated coupling 42.

[0074] In one embodiment of this application, such as Figure 5 As shown, a first oblique spline 123 is provided on the first end 121 of the shaft. The load conversion mechanism 30 includes a support base 31, a support bearing 32, and a sleeve 33. The top end of the support base 31 is provided with a support cavity. The sleeve 33 has a first end 331 and a second end 332. The first end 331 is sleeved outside the first end 121 of the shaft, and a second oblique spline 333 matching the first oblique spline 123 is provided on the inner wall of the first end 331. The second end 332 is inserted into the support cavity. The support bearing 32 is fixed inside the support cavity and sleeved outside the second end 332, so that the second end 332 can be transmitted through the support bearing 32 to the inner wall of the support cavity, ensuring the stability of the rotation of the sleeve 33.

[0075] In one embodiment of this application, such as Figure 1 As shown, the torque loading mechanism 20 includes a magnetic powder brake 21, a brake coupling 22, a torque and speed sensor 23, a torque measuring insulated coupling 24, and a brake controller 25. The magnetic powder brake 21 is connected to the torque and speed sensor 23 via the brake coupling 22. The torque and speed sensor 23 is connected to the second end 122 of the shaft via the torque measuring insulated coupling 24. Both the torque and speed sensor 23 and the magnetic powder brake 21 are electrically connected to a data acquisition mechanism. The torque and speed sensor 23 is used to measure the torque and speed of the bearing sample 13 in real time and transmit the measured torque and speed information to the data acquisition mechanism in real time. The brake controller 25 is electrically connected to the magnetic powder brake 21 and is used to regulate the load applied to the bearing sample 13 by the magnetic powder brake 21. During operation, a load is applied to the bearing sample 13 by the magnetic powder brake 21, and the torque and speed of the bearing sample 13 are measured by the torque and speed sensor 23. When the load applied to the bearing by the magnetic powder brake 21 needs to be changed, the load is changed by controlling the magnetic powder brake 21 through the brake controller 25.

[0076] Furthermore, the torque loading mechanism 20 also includes a water cooler 26, which is connected to the magnetic powder brake 21 and is used to cool the magnetic powder brake 21 with water to ensure the performance and service life of the magnetic powder brake 21.

[0077] In one embodiment of this application, such as Figure 6 As shown, the voltage loading mechanism 50 includes a power supply measurement component, a first wire 53, and a carbon brush assembly. The power supply measurement component, the first wire 53, the carbon brush assembly, and the bearing assembly are connected in series to form a closed experimental circuit. One end of the first wire 53 is connected to the power supply measurement component, and the other end is connected to the mounting box 11 that contacts the outer ring of the bearing sample 13. The carbon brush assembly is electrically connected to the power supply measurement component and the rotating shaft 12 that contacts the inner ring of the bearing sample 13.

[0078] Furthermore, the power supply measurement component includes a signal generator 51 and a power amplifier 52. The power amplifier 52 is electrically connected to the first wire 53 and the carbon brush assembly, and the signal generator 51 is electrically connected to the power amplifier 52 for connecting to an external power source. After the external power source is turned on, the external power is supplied to the power amplifier 52 through the signal generator 51. The power amplifier 52 increases the voltage of the power source as needed, and then supplies the increased voltage power to the bearing sample 13, causing the bearing sample 13 to be energized and generate current.

[0079] Furthermore, the carbon brush assembly includes a bracket 54, a carbon brush 55, and a second wire 56. One end of the carbon brush 55 is mounted on the bracket 54 and connected to the power amplifier 52 of the power supply measurement component via the second wire 56. The other end of the carbon brush 55 rests on the rotating shaft 12.

[0080] In one embodiment of this application, such as Figure 6As shown, the oil supply mechanism 60 includes an oil tank 61, an oil inlet pipe 62, an oil outlet pipe 63, an oil inlet pump 641, an oil outlet pump 642, an oil temperature measurement module, an oil pressure measurement module 65, and a heat exchanger 66. The oil tank 61, the oil inlet pipe 62, the oil outlet pipe 63, and the mounting box 11 are connected in series to form a closed oil supply circuit. The oil tank 61 is selected as an existing oil storage structure with oil heating and oil pressure regulation. The oil inlet pipe 62 and the oil outlet pipe 63 are fixed on the mounting box 11 and are respectively connected to the oil inlet hole 1111 and the oil outlet hole 1114. The oil inlet pump 641, the oil pressure measurement module 65, and the heat exchanger 66 are installed on the oil inlet pipe 62, and the oil outlet pump 642 is installed on the oil outlet pipe 63. The oil pump 641 is used to drive the lubricating oil in the oil tank to the bearing sample 13. The oil pressure measurement module 65 uses a pressure gauge. During the experiment, the staff observes the pressure data of the pressure gauge and controls the oil pressure adjustment structure of the oil tank 61 to adjust the output oil pressure of the oil tank 61 to the oil pressure required for the experiment. The heat exchanger 66 is used to regulate the temperature of the lubricating oil in the oil inlet pipe and is set near the gearbox 11. When regulating the temperature, the oil tank 61 first heats the oil to the specified temperature through its own oil heating structure. This specified temperature is higher than the temperature required for lubrication of the bearing sample 13. Then, the heat exchanger 66 precisely cools the lubricating oil to the temperature required for lubrication of the bearing sample 13. The oil pump 642 is used to drive the lubricating oil in the mounting cavity 114 back to the oil tank 61. The oil temperature measurement module includes an inlet oil temperature sensor 67 and an outlet oil temperature sensor 68. In order to ensure that the oil temperature of the lubricating oil delivered to the bearing sample 13 is very close to the oil temperature required for the experiment and to ensure the accuracy of the experiment, the inlet oil temperature sensor 67 is located at one end of the oil inlet pipe 62 that connects to the mounting cavity 114, and the outlet oil temperature sensor 68 is located at one end of the oil outlet pipe 63 that connects to the mounting cavity 114. During the experiment, the heating mode of the heat exchanger 66 and the oil tank 61 is controlled by the inlet oil temperature measured by the inlet oil temperature sensor 67 and the outlet oil temperature measured by the outlet oil temperature sensor 68, so that the temperature of the lubricating oil delivered to the bearing sample 13 is the required oil temperature.

[0081] In one embodiment of this application, the data acquisition mechanism is a split structure, such as... Figure 1As shown, the data acquisition mechanism includes a torque and speed information acquisition display 71 electrically connected to the torque and speed sensor 23, a digital oscilloscope 72 electrically connected to the power amplifier 52, and a temperature acquisition display (not shown) electrically connected to the inlet oil temperature sensor 67 and the outlet oil temperature sensor 68. The torque and speed information acquisition display 71 acquires and displays the torque and speed of the bearing sample 13; the digital oscilloscope 72 acquires and displays the voltage applied to the bearing sample 13 and the current flowing through it during the experiment; and the temperature acquisition display acquires and displays the lubricating oil temperature information acquired by the inlet oil temperature sensor 67 and the outlet oil temperature sensor 68. During the experiment, the acquired data is recorded. In other feasible embodiments, the data acquisition mechanism can be configured as an integrated structure, that is, a control device that integrates the torque and speed information acquisition display 71, the digital oscilloscope 72, and the temperature acquisition display into one unit, such as an industrial all-in-one machine or a multi-functional industrial control device.

[0082] In one embodiment of this application, the bearing testing apparatus further includes an insulating base 80 disposed below the bearing testing mechanical mechanism 10, and the mounting box 11 of the bearing testing mechanical mechanism 10 is detachably mounted on the insulating base 80. The insulating base 80 enables the bearing testing mechanical mechanism 10 to be insulated from the outside or the ground, further ensuring that the current path is strictly limited to the closed experimental circuit of "voltage loading mechanism 50 → bearing assembly → mounting box 11 → voltage loading mechanism 50".

[0083] The present invention also provides a bearing electrical breakdown test method, comprising the following steps:

[0084] S10. Provide the bearing test apparatus as described above, and perform pre-test preparation work on the bearing test apparatus.

[0085] S20, Start the oil supply mechanism 60 to lubricate bearing sample 13.

[0086] Specifically, during the start-up of the oil supply mechanism 60, after adjusting parameters such as oil temperature and oil pressure, the oil temperature and oil pressure are controlled by the oil heating structure and oil pressure control structure of the oil tank 61. Then, the oil pump 64 of the oil supply mechanism 60 drives the oil tank 61 to deliver lubricating oil to the bearing sample 13, so that an oil film is formed on the surface of the roller of the bearing sample 13 in contact with the inner ring and on the surface of the roller of the bearing sample 13 in contact with the outer ring.

[0087] S30. Determine the working parameters for the electrical breakdown test. The working parameters for the electrical breakdown test include the bearing sample rotation speed, bearing sample torque, and the frequency and magnitude of the simulated voltage applied to the bearing sample. Based on the determined working parameters for the electrical breakdown test, start and adjust the torque loading mechanism 20, the power mechanism 40, and the voltage loading mechanism 50, and continue for a specified time. Then, while keeping the frequency of the simulated voltage, the bearing sample rotation speed, and the bearing sample torque constant, gradually increase the simulated voltage and monitor the change in current flowing through the bearing sample 13. Each time the simulated voltage is increased, continue for a specified time. When a sudden increase in current is detected, stop the experiment. Record the experimental data during the test.

[0088] Specifically, based on the determined initial electrical breakdown test parameters, the power mechanism 40 and torque loading mechanism 20 are first started and adjusted to ensure that the rotational speed and torque of the bearing sample 13 reach the determined values ​​in the electrical breakdown test parameters. After stable operation, an external power supply is turned on, and a simulated voltage of a specified frequency and magnitude is applied to the bearing sample 13 through the voltage loading mechanism 50 for a specified duration. The magnitude of the current flowing through the bearing sample 13 is monitored using a digital oscilloscope in the voltage loading mechanism 50. Then, while keeping the bearing sample rotational speed, bearing sample torque, and simulated voltage frequency constant, the simulated voltage is gradually increased, with each increase lasting for a specified duration. When a sudden increase in current is detected, it indicates that the oil film layer of the bearing sample 13 has been broken down. The experiment is stopped, and the voltage, current, oil temperature, and other data are recorded. The bearing sample 13 is retained for subsequent inspection and analysis.

[0089] For example, as shown in Table 1, initially, the rotational speed of bearing sample 13 was adjusted to 40 rpm, and the torque of magnetic powder brake 21 was adjusted to 20 Nm. After the operation stabilized, an external power supply was turned on, and a simulated voltage of 0.1V with a frequency of 20Hz was applied to bearing sample 13 through voltage loading mechanism 50 for 3-5 minutes. Subsequently, the simulated voltage was gradually increased by 0.1V at a time through power amplifier 52 in voltage loading mechanism 50, with each increase lasting 3-5 minutes. Current and oil temperature data were recorded each time the simulated voltage was increased. The experiment was stopped when a sudden increase in current was detected. The relevant data obtained from the experiment are recorded in Table 1 below.

[0090] Table 1 Recording Table of Electrical Breakdown Experiment Data

[0091]

[0092]

[0093] S40. Replace the bearing sample 13 with one of the same specifications and repeat steps S20 and S30 continuously. The replacement bearing sample 13 is adjusted according to the electrical breakdown test procedure during the experiment.

[0094] Specifically, the bearing samples 13 that are replaced are all bearing samples of the same specification. When replacing the bearing sample 13, the entire bearing assembly is not replaced. Since the bearing sample 13 can be detachably installed on the rotating shaft 12, only the bearing sample 13 needs to be replaced. In order to shorten the replacement time, two rotating shafts 12 are provided. When the bearing sample 13 is installed on one rotating shaft 12 and tested in the mounting box 11, the other rotating shaft 12 can be installed on the bearing sample 13 outside the mounting box 11 at the same time. The shafts are switched immediately after the electrical breakdown test is completed, so as to achieve seamless connection between the replacement of the bearing sample 13 and the bearing sample test.

[0095] Please refer to Table 2, which is the electrical breakdown test scheme. The test of the replaced bearing sample 13 is carried out according to Table 2. The bearing sample rotation speed, bearing sample torque, and the magnitude and frequency of the simulated voltage applied to the bearing sample 13 are adjusted in the electrical breakdown test working parameters.

[0096] Table 2 Electrical Breakdown Test Procedure

[0097]

[0098] S50. Based on the recorded experimental data, calculate the minimum oil film thickness value of the bearing sample 13 when it is electrically broken down under different electrical breakdown test operating parameters, and mark the minimum breakdown voltage of the bearing sample 13 under different electrical breakdown test operating parameters.

[0099] Specifically, the bearing types in existing wind turbine gearboxes are mainly tapered roller bearings and cylindrical roller bearings. Considering that shaft voltage has a greater impact on the high-speed stage tapered roller bearings near the motor end, the high-speed stage tapered roller bearings are selected as the research object. According to the "Roller Bearing Design Principles", the calculation formula for the minimum oil film thickness of the tapered roller bearing under full film lubrication is as follows:

[0100]

[0101] In equation (1), α is the viscosity coefficient, with units of Pa. -1 η0 is the dynamic viscosity of the lubricating oil under normal pressure, in Pa·s, which can be obtained from the relevant parameters of the required lubricating oil; u is the average surface velocity, in m / s; R is the equivalent radius of curvature, in m; l is the effective contact length, in m; Q max E0 represents the maximum load on the roller of bearing specimen 13; E0 is the comprehensive elastic modulus of bearing specimen 13, in Pa.

[0102] The formula for calculating u in Equation 1 is:

[0103]

[0104] In Equation 2, d is the diameter of the inner ring of bearing sample 13; n is the rotational speed of bearing sample 13.

[0105] Q in Equation 1 max The calculation formula is:

[0106]

[0107] In Equation 3, z is the number of rolling elements in bearing specimen 13, T is the torque of bearing specimen (N·m), n is the rotational speed of the inner ring of bearing specimen 13 (rad / s), θ is the contact angle of bearing specimen 13 (°), β is the semi-cone angle of the roller (°), and m is the mass of bearing specimen 13 (g).

[0108] In Equations 1, 2, and 3, R, l, E0, d, z, θ, and m can all be obtained from the relevant parameters of the selected tapered roller bearing. In Equation 1, α and η0 can both be obtained from the relevant parameters of the selected lubricating oil.

[0109] For example, when a tapered roller bearing with dimensions of φ100xφ140xφ25mm and model number 32390 is selected as the experimental bearing sample 13, and ISO VG320 lubricating oil is selected as the experimental lubricating oil, R, l, E0, d, z, θ, and m in Equations 1, 2, and 3 are obtained from the relevant parameters of tapered roller bearing 32920 shown in Table 3 below, and α and η0 in Equation 1 are obtained from the relevant parameters of lubricating oil ISO VG320 shown in Table 4 below.

[0110] Table 3. Relevant parameters of tapered roller bearing 32920

[0111]

[0112]

[0113] Table 4. Relevant parameters of lubricating oil I S0 VG320

[0114] name Operating temperature density kinematic viscosity Dynamic viscosity ISO VG 320 50℃ <![CDATA[870kg / m 3 ]]> <![CDATA[192mm 2 / s]]> <![CDATA[167mNs / m 2 ]]>

[0115] In one embodiment of this application, step S10 includes pre-assembly preparation and post-assembly preparation of the gear testing device.

[0116] The preparations before device assembly include the following steps:

[0117] S11. Re-inspect bearing sample 13 to ensure it meets design requirements.

[0118] S12. Individually debug the torque loading mechanism 20, power mechanism 40, voltage loading mechanism 50 and oil supply mechanism 60 to ensure that each mechanism is in normal working condition.

[0119] Specifically, before assembly, the magnetic powder brake 21 of the torque loading mechanism 20, the adjustable speed motor 41 of the power mechanism 40, the power supply measurement component of the voltage loading mechanism 50, and the oil pump 64 of the oil supply mechanism 60 are individually tested to ensure that each mechanism can work normally.

[0120] S13. Replace the lubricating oil in the oil supply mechanism 60 with a suitable lubricating oil according to the selected bearing sample model.

[0121] S14. Inspect the bearing sample 13 and record the inspection results.

[0122] Specifically, the inspection records include the serial number, appearance quality, dimensional accuracy, surface morphology, etc., and photos are taken as evidence.

[0123] S15. Mark the rotation direction of bearing sample 13 for comparative analysis before and after the experiment.

[0124] In step S10, the preparation after assembly includes the following steps:

[0125] Debug the experimental setup and check that all connections are in place to ensure the setup operates without any abnormalities.

[0126] The bearing electrical breakdown test method of the present invention, by employing the bearing test apparatus described above for electrical breakdown testing, can perform high-precision electrical breakdown tests on tapered roller bearing samples under oil lubrication conditions, thereby significantly improving the reliability of electrical breakdown test data.

[0127] like Figure 7 As shown, the present invention also provides a bearing testing apparatus for bearing electro-erosion experiments. The structure of this bearing testing apparatus for electro-erosion experiments is very similar to the structure of the bearing electrical breakdown experiment apparatus described above. The difference lies in that the bearing electro-erosion apparatus further includes a vibration sensor 90 for measuring the vibration of the bearing sample 13. In some embodiments, the vibration sensor 90 may be as follows: Figure 7The accelerometer 90, mounted on the outer wall of the mounting box 11, is arranged to effectively capture the vibration signal of the bearing sample 13, as the vibration of the bearing sample 13 is transmitted to the mounting box 11. In other feasible embodiments, the vibration sensor 90 can also be a laser vibrometer located on one side of the mounting box 11, acquiring the vibration velocity / displacement of the bearing sample 13 through the Doppler effect or interferometry to obtain the vibration information of the bearing sample 13. The vibration sensor 90 is electrically connected to the data acquisition mechanism to transmit the measured vibration information to the data acquisition mechanism. When the corrosion of the bearing sample 13 is severe, the vibration data will suddenly increase. By continuously conducting experiments while keeping the bearing sample torque, bearing sample rotation speed, and the magnitude and frequency of the analog voltage applied to the bearing sample constant, the vibration sensor 90 monitors the vibration changes of the bearing sample 13 to achieve the purpose of monitoring the electrical corrosion of the bearing sample 13.

[0128] The bearing test apparatus with vibration sensor 90 described above can accurately simulate the actual operating conditions of tapered roller bearings in the generator gearbox integrated system under oil lubrication conditions, thereby enabling precise electro-erosion tests to be conducted on bearing specimens 13 under oil lubrication conditions.

[0129] It should be noted that the bearing test apparatus with vibration sensor described above can be used not only for the electrical erosion test of bearing specimens, but also for the electrical breakdown test of bearing specimens. When used for the electrical breakdown test of bearing specimens, the operation of vibration sensor 90 is ignored.

[0130] In one embodiment of this application, based on the bearing testing apparatus equipped with a vibration sensor 90, such as Figure 7 As shown, the data acquisition mechanism also includes a vibration display 73 electrically connected to the vibration sensor 90. The vibration display 73 acquires and displays the vibration information monitored by the vibration sensor 90.

[0131] The present invention also provides a bearing electro-erosion test method, comprising the following steps:

[0132] S10. Provide the bearing test apparatus with vibration sensor 90 as described above, and perform pre-test preparation work on the bearing test apparatus.

[0133] S20. Determine the working parameters of the electrical erosion test for the bearing sample 13. The working parameters of the electrical erosion test include the rotational speed of the bearing sample, the torque of the bearing sample, and the frequency of the simulated voltage applied to the bearing sample 13. Based on the determined working parameters of the electrical erosion test and the experimental results obtained by the bearing electrical breakdown test method described above, determine the minimum breakdown voltage of the bearing sample 13. Set the magnitude of the simulated voltage applied to the bearing sample 13 based on the minimum breakdown voltage.

[0134] Specifically, after determining the working parameters for the electro-erosion test of bearing sample 13, the corresponding minimum breakdown voltage value is found from Table 1 above based on the bearing sample rotation speed and bearing sample torque values ​​in the determined working parameters. Then, the magnitude of the simulated voltage applied to bearing sample 13 is set according to the minimum breakdown voltage. The simulated voltage must be greater than the minimum breakdown voltage. Generally, the simulated voltage is set to 5 times, 10 times, 20 times, etc. of the minimum breakdown voltage to ensure that bearing sample 13 directly enters the electro-erosion stage.

[0135] S30, Start the oil supply mechanism 60 to lubricate the bearing sample.

[0136] Specifically, during the start-up of the oil supply mechanism 60, after adjusting parameters such as oil temperature and oil pressure, the oil temperature and oil pressure are achieved through the oil heating structure and oil pressure control structure of the oil tank 61. Then, the oil pump 64 of the oil supply mechanism 60 drives the oil tank 61 to deliver lubricating oil to the bearing sample 13, so that an oil film layer is formed on the surface of the roller of the bearing sample 13 in contact with the inner ring and on the surface of the roller of the bearing sample 13 in contact with the outer ring.

[0137] S40, starting the power mechanism 40, voltage loading mechanism 50 and torque loading mechanism 20, adjust the torque and speed of the bearing sample 13, as well as the magnitude and frequency of the simulated voltage applied to the bearing sample 13, according to the working parameters of the electro-erosion experiment determined in step S20, keep the working parameters of the electro-erosion experiment unchanged and continue the experiment, monitor the vibration change of the bearing sample in real time through the vibration sensor 90, stop the experiment when a sudden increase in vibration is detected, observe the macro- and micro-morphology of the surface of the bearing sample 13 after the experiment, and record the relevant experimental data.

[0138] Specifically, an electro-erosion experiment data table is prepared. First, the initially determined electro-erosion experiment working parameters are recorded in the electro-erosion experiment data table. Then, the power mechanism 40 and torque loading mechanism 20 are started, followed by the voltage loading mechanism 50. According to the determined electro-erosion experiment working parameters and the magnitude of the simulated voltage, the rotational speed and torque of the bearing sample, as well as the magnitude and frequency of the simulated voltage applied to the bearing sample, are adjusted and the experiment is continued. When a sudden increase in vibration is detected in the bearing sample 13, it indicates that the corrosion degree of the surface of the bearing sample 13 has reached or exceeded the expected corrosion degree. The experiment is stopped, and the voltage, current, oil temperature, vibration acceleration of the bearing sample 13, and experiment duration are recorded in the electro-erosion experiment data table. Subsequently, the bearing sample 13 is removed from the mounting box 11, and the macro- and micro-morphological morphology of the bearing sample surface after the experiment is observed and analyzed. The relevant data on the surface morphology analysis of the bearing sample 13 are recorded in the electro-erosion experiment data table for subsequent analysis.

[0139] For example, the experimental data is recorded using the electrical erosion test data table shown in Table 5 below. Initially, the adjustable speed motor speed in the bearing sample's working parameters is set to 40 rpm, the torque of the bearing sample is set to 20 Nm, and the simulated voltage applied to the bearing sample is set to a frequency of 20 Hz. Based on the set working parameters of the bearing sample and the electrical breakdown test data, the magnitude of the simulated voltage is set to 5V. Based on the set electrical erosion test working parameters and the magnitude of the simulated voltage, the speed of the adjustable speed motor 21 of the power mechanism 40 is adjusted to 40 rpm, and the torque loading mechanism 2... The torque of the magnetic powder brake 31 was adjusted to 20 Nm. After stable operation, the external power supply was turned on, and a voltage of 5V with a frequency of 20 Hz was applied to the bearing sample 13 through the voltage loading mechanism 50. The rotational speed and torque of the bearing sample, as well as the magnitude and frequency of the simulated voltage, were kept constant during the experiment. The vibration changes of the bearing sample were observed through the vibration sensor 90. When a sudden increase in the vibration of the bearing sample was detected, the experiment was stopped, the bearing sample was removed from the mounting box 11, and the macro- and micro-morphological morphology of the bearing sample surface after the experiment was observed and analyzed. The relevant data obtained during the entire electro-erosion experiment are recorded in Table 5 below.

[0140] Table 5. Data Recording Sheet for Electro-Erosion Experiment

[0141]

[0142] S50. Replace bearing sample 13 and repeat steps S20 to S40 continuously. The working parameters of the electro-erosion test are adjusted according to the electro-erosion test plan for the replaced bearing sample 13.

[0143] Specifically, all the bearing samples replaced are bearings of the same specification. When replacing bearing sample 13, the entire bearing assembly is not replaced. Since bearing sample 13 can be detachably installed on the rotating shaft 12, only bearing sample 13 needs to be replaced. In order to shorten the replacement time, two rotating shafts 12 are provided. When one rotating shaft 12 is equipped with bearing sample 13 and is being tested in the mounting box 11, the other rotating shaft 12 can be simultaneously installed outside the mounting box 11. The shafts are switched immediately after the electrical breakdown test is completed, thereby achieving a seamless connection between the replacement of bearing sample 13 and the bearing sample test.

[0144] Please refer to Table 6 below. Table 6 is the electro-erosion test scheme table. During the experiment, the bearing sample 13 was replaced. The bearing sample rotation speed, bearing sample torque and frequency of the voltage applied to the bearing sample 13 were adjusted according to Table 2. After each adjustment, the experimental data were recorded in Table 5 above.

[0145] Table 6 Electro-erosion test scheme

[0146]

[0147] S60. Analyze the experimental data.

[0148] Specifically, the effects of different voltages, torques, and rotational speeds on the electro-erosion of bearing sample 13 were analyzed using experimental data.

[0149] The electro-erosion test method of the present invention, by employing the bearing test device with vibration sensor 90 described above, can perform high-precision electro-erosion tests on tapered roller bearing samples under oil lubrication conditions, thereby significantly improving the reliability of electro-erosion test data.

[0150] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A bearing testing apparatus, characterized in that, include: A bearing testing mechanism includes a mounting box and a bearing assembly; the mounting box has a mounting cavity, and the bearing assembly is detachably installed in the mounting cavity; the bearing assembly includes a rotating shaft and a bearing sample detachably installed on the rotating shaft, the rotating shaft having a first shaft end and a second shaft end, and the bearing sample being a tapered roller bearing; A torque loading mechanism, insulated from the second end of the shaft, is used to apply an adjustable torque to the bearing sample; A load conversion mechanism, installed on the first end of the shaft, is used to convert the torque applied by the torque loading mechanism into an axial force on the bearing sample, and to monitor the torque and rotational speed of the bearing sample. The power mechanism, which is insulated from the load conversion mechanism, is used to provide power for the rotation of the bearing sample; An oil supply mechanism, connected to the mounting cavity, is used to supply lubricating oil to the bearing sample; A voltage loading mechanism, electrically connected to the bearing assembly, is used to apply an adjustable voltage to the bearing sample and monitor the current flowing through the bearing sample; and The data acquisition mechanism is electrically connected to the torque loading mechanism and the voltage loading mechanism, and is used to acquire experimental data.

2. The bearing experimental apparatus according to claim 1, characterized in that, The mounting box includes a main body, a first cover, and a second cover; the mounting cavity is formed inside the main body, and the main body has openings on both sides. The main body includes a detachably connected upper half and a lower half, which enclose the mounting cavity; both the first cover and the second cover are detachably mounted on the main body and respectively seal the openings on both sides of the main body; the first end and the second end of the shaft pass through the first cover and the second cover, respectively.

3. The bearing experimental apparatus according to claim 2, characterized in that, The mounting cavity has a first cavity, a second cavity, and a third cavity located between the first cavity and the second cavity. The bearing sample is located in the third cavity. The main housing has an oil inlet, an oil outlet, an oil reservoir, and an intermediate hole. The oil reservoir is located at the bottom of the second cavity. The oil inlet, the intermediate hole, and the oil outlet are all located within the main housing. The oil inlet and the intermediate hole are located above and below the mounting cavity, respectively. The oil inlet connects the oil outlet of the oil supply mechanism and the mounting cavity. The intermediate hole extends along the axial direction of the rotating shaft, and its two ends connect the first cavity and the oil reservoir, respectively. The oil outlet connects to the oil reservoir.

4. The bearing testing apparatus according to claim 3, characterized in that, The number of intermediate holes is at least two, and the intermediate holes are arranged sequentially at intervals along a horizontal direction perpendicular to the axis of rotation.

5. The bearing testing apparatus according to claim 3, characterized in that, Both the oil drain hole and the oil storage tank extend straight in the horizontal direction. The wall of the oil storage tank is arc-shaped and is coaxial with the oil drain hole. The diameter of the wall of the oil storage tank is equal to the diameter of the oil drain hole.

6. The bearing testing apparatus according to claim 1, characterized in that, The first end of the shaft is provided with a first oblique spline. The load conversion mechanism includes a support seat, a support bearing, and a sleeve. The top end of the support seat is provided with a support cavity. The sleeve has a first end and a second end. The first end of the sleeve is sleeved outside the first end of the shaft, and the inner wall of the first end of the sleeve is provided with a second oblique spline that matches the first oblique spline. The second end of the sleeve is inserted into the support cavity. The support bearing is fixed inside the support cavity and sleeved outside the second end of the sleeve.

7. The bearing testing apparatus according to claim 1, characterized in that, The torque loading mechanism includes a magnetic powder brake, a brake coupling, a torque and speed sensor, a torque measurement insulated coupling, and a brake controller; the magnetic powder brake is connected to the torque and speed sensor via the brake coupling; the torque and speed sensor is connected to the second end of the shaft via the torque measurement insulated coupling; both the torque and speed sensor and the magnetic powder brake are electrically connected to a data acquisition mechanism; the brake controller is electrically connected to the magnetic powder brake.

8. The bearing testing apparatus according to any one of claims 1 to 7, characterized in that, It also includes a vibration sensor electrically connected to the data acquisition mechanism, the vibration sensor being used to measure the vibration of the bearing sample.

9. A bearing electrical breakdown test method, characterized in that, Includes the following steps: S10. Provide the bearing testing apparatus as described in any one of claims 1 to 7, and perform pre-experiment preparation work on the testing apparatus; S20. Start the oil supply mechanism to lubricate the bearing sample; S30. Determine the working parameters for the electrical breakdown test. The working parameters include the bearing sample rotation speed, bearing sample torque, and the frequency and magnitude of the simulated voltage applied to the bearing sample. Based on the determined working parameters, start and adjust the power mechanism, the torque loading mechanism, and the voltage loading mechanism for a specified time. Then, while keeping the frequency and magnitude of the simulated voltage, the bearing sample rotation speed, and the bearing sample torque constant, gradually increase the simulated voltage and monitor the change in current flowing through the bearing sample. Each increase in simulated voltage is also maintained for a specified time. When a sudden increase in current is detected, stop the experiment. Record the experimental data during the experiment. S40. Replace the bearing sample and repeat steps S20 and S30 continuously. The replaced bearing sample is adjusted according to the electrical breakdown test working parameters in the experiment according to the electrical breakdown test plan. S50. Based on the recorded experimental data, calculate the minimum oil film thickness value of the bearing sample when it is electrically broken down under different electrical breakdown test operating parameters, and mark the minimum breakdown voltage of the bearing sample under different electrical breakdown test operating parameters.

10. A bearing electro-erosion test, characterized in that, Includes the following steps: S10. Provide the bearing testing apparatus as described in claim 8, and perform pre-experiment preparation work on the bearing testing apparatus. S20. Determine the working parameters of the bearing sample electro-erosion test. The working parameters of the electro-erosion test include the bearing sample rotation speed, bearing sample torque and the frequency of the simulated voltage applied to the bearing sample. Based on the determined working parameters of the electro-erosion test and the experimental results obtained by the bearing electrical breakdown test method as described in claim 9, determine the minimum breakdown voltage of the bearing sample. Set the magnitude of the simulated voltage based on the minimum breakdown voltage. S30. Start the oil supply mechanism to lubricate the bearing sample; S40. Start the power mechanism, the voltage loading mechanism and the torque loading mechanism. According to the working parameters of the electro-erosion experiment and the magnitude of the simulated voltage determined in step S20, adjust the torque and speed of the bearing sample, as well as the magnitude and frequency of the simulated voltage applied to the bearing sample. Keep the working parameters of the electro-erosion experiment unchanged and continue the experiment. Monitor the vibration changes of the bearing sample in real time through the vibration sensor. When a sudden increase in vibration is detected, stop the experiment, observe the macro- and micro-morphology of the surface of the bearing sample after the experiment, and record the relevant experimental data. S50. Replace the bearing sample and repeat steps S20 to S40 continuously. After replacement, adjust the working parameters of the electro-erosion test according to the electro-erosion test plan during the experiment. S60. Analyze the experimental data.

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