High-strength bolt fatigue testing machine for TBM and testing method

Abstract

The invention discloses a high-strength bolt fatigue testing machine for a TBM. The high-strength bolt fatigue testing machine comprises a bottom plate, a supporting table, a first stand column, a second stand column, a transverse force loading device, an axial force loading device, a torque force loading device, an upper clamp, a lower clamp, a to-be-tested bolt, a to-be-tested bolt nut and a data acquisition and control system. The invention further provides a testing method of the high-strength bolt fatigue testing machine for the TBM. According to the invention, a transverse force, an axial force and a torque force can be applied to the to-be-tested bolt at the same time, and compared with a test device for singly applying the axial force or the torque force in the prior art, a complex stress environment of the to-be-tested bolt in an actual working state can be truly simulated; moreover, the size and direction of the force are accurately adjusted through a data acquisition and control system, the accuracy and reliability of the test result are remarkably improved, the test process is more intelligent, and the method has important application value in the engineering field of TBM and the like.

Description

Technical Field

[0001] The invention relates to the technical field of bolt fatigue testing, and in particular to a high-strength bolt fatigue testing machine for TBM and a testing method. Background Art

[0002] TBM, or full-face tunnel boring machine, generates complex stresses and vibrations during operation, and the high-strength bolts acting on it must withstand the interaction of multiple loads such as lateral force, axial force, and torque. Most traditional high-strength bolt fatigue testing machines can only apply axial force or torque force alone, and cannot simulate the actual load environment of high-strength bolts under TBM working conditions. It is difficult to accurately evaluate the fatigue performance of high-strength bolts under complex stress conditions and cannot meet the actual needs of the project. Therefore, there is a need for a testing machine and test method that can truly simulate TBM working conditions and perform fatigue tests on high-strength bolts to evaluate their fatigue performance. Summary of the invention

[0003] In order to solve the above problems, an object of the present invention is to provide a high-strength bolt fatigue testing machine and a testing method for TBM.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present invention is: a high-strength bolt fatigue testing machine for TBM, comprising a base plate, a support platform, a first column, a second column, a lateral force loading device, an axial force loading device, a torque loading device, an upper fixture, a lower fixture, a bolt to be tested, a bolt nut to be tested and a data acquisition and control system, wherein the base plate is provided with a first column and a second column in a vertical direction, a support platform is provided in front of the second column, a fixing seat and a lateral force loading device are installed on the first column, the second column is a telescopic structure, the top end of the second column is fixed to the middle beam, the lower end of the middle beam is connected to the axial force loading device, the lower end of the axial force loading device is connected to the upper fixture, the torque loading device is installed on the base plate in a vertical direction and is connected to the support platform, the upper end of the torque loading device is connected to the lower fixture, the upper end and the lower end of the bolt to be tested are respectively fixed to the bottom end of the upper fixture and the top end of the lower fixture through the bolt nut to be tested, and the lateral force loading device is connected to the bolt to be tested between the upper fixture and the lower fixture;

[0005] The lateral force loading device applies lateral force to the bolt to be tested, so as to realize the lateral force loading of the bolt to be tested;

[0006] The axial force loading device applies axial force to the upper fixture, and the upper fixture and the lower fixture work together to transmit the axial force to the bolt to be tested, thereby realizing the loading of the axial force of the bolt to be tested;

[0007] The torque force loading device applies torque force to the lower fixture to achieve torque force loading on the bolt to be tested;

[0008] The lateral force loading device, the axial force loading device, and the torque force loading device are respectively connected to the data acquisition and control system, through which the lateral force, axial force, and torque force data applied to the bolt to be tested are obtained, and the actions of the lateral force loading device, the axial force loading device, and the torque force loading device are controlled; the data acquisition and control system is also connected to the second column to adjust the height of the second column.

[0009] Furthermore, the lateral force loading device includes a lateral force hydraulic cylinder, a lateral force piston rod, a power rod, an end actuator and a lateral force clamp. The lateral force hydraulic cylinder is fixed on the first column, and the fixed end of the lateral force hydraulic cylinder is connected to the fixed seat. The telescopic end of the lateral force hydraulic cylinder is connected to the power rod through the lateral force piston rod, and the other end of the power rod is connected to the end actuator. The end actuator is used to control the opening and closing of the lateral force clamp. When the end actuator controls the lateral force clamp to close, the lateral force clamp clamps the bolt to be tested, and the lateral force hydraulic cylinder drives the lateral force piston rod to reciprocate in the horizontal direction, thereby driving the power rod, the end actuator and the lateral force clamp to reciprocate in the horizontal direction, thereby realizing the loading of the lateral force on the bolt to be tested and the adjustment of the size of the lateral force; after completing the fatigue test, the end actuator controls the lateral force clamp to open and releases the clamping force on the bolt to be tested.

[0010] Furthermore, the end actuator includes a cylinder and a telescopic rod, the output end of the cylinder is connected to the telescopic rod, the lateral force clamp includes two clamping jaws, two connecting arms, a fixed plate and a locking nut, the fixed plate is fixed to the front end of the telescopic rod by a locking nut, connecting arms are hinged at both ends of the fixed plate, the other end of each connecting arm is hinged to the clamping jaws, and the ends of the two clamping jaws are hinged to the cylinder respectively; the cylinder is connected to the data acquisition and control system, the data acquisition and control system controls the movement of the cylinder, and the telescopic rod is driven by the cylinder to move forward and backward in the horizontal direction, thereby driving the two connecting arms to rotate along the two ends of the fixed plate to realize the closing and opening of the two clamping jaws.

[0011] Furthermore, a semicircular through hole is provided on the inner side of the front end of the clamping jaw. When the two clamping jaws are closed, the two semicircular through holes are connected to form a circular through hole. The inner diameter of the circular through hole matches the outer diameter of the bolt to be tested, thereby clamping the bolt to be tested.

[0012] Furthermore, the lateral force loading device also includes a lateral force sensor. The lateral force hydraulic cylinder and the lateral force sensor are respectively connected to the data acquisition and control system. The lateral force sensor is installed at the end of the power rod. The lateral force sensor is used to obtain lateral force data in real time, and convert the force signal of the lateral force data into an electrical signal, and send it to the data acquisition and control system. The lateral force data is processed and analyzed by the data acquisition and control system, and the lateral force hydraulic cylinder is controlled to drive the lateral force piston rod to move according to the size of the lateral force, so as to realize the loading and adjustment of the lateral force of the bolt to be tested.

[0013] Furthermore, the axial force loading device includes an axial force hydraulic cylinder and a hydraulic push rod. The axial force hydraulic cylinder is fixed on the middle beam. The top of the hydraulic push rod is connected to the axial force hydraulic cylinder, and the other end is connected to the top of the upper clamp. The axial force hydraulic cylinder drives the hydraulic push rod to move up and down in the axial direction, thereby applying axial force to the upper clamp. The upper clamp and the lower clamp work together to transmit the axial force to the bolt to be tested, thereby realizing the loading of the axial force of the bolt to be tested.

[0014] Furthermore, the axial force loading device also includes an axial force sensor. The axial force hydraulic cylinder and the axial force sensor are respectively connected to the data acquisition and control system. The axial force sensor is installed at the connection between the lower end of the upper clamp and the bolt to be tested. The axial force sensor is used to obtain axial force data in real time, and convert the force signal of the obtained axial force data into an electrical signal, and send it to the data acquisition and control system. The axial force data is processed and analyzed by the data acquisition and control system, and the axial force hydraulic cylinder is driven to operate according to the size of the axial force, so as to realize the loading and adjustment of the axial force of the bolt to be tested.

[0015] Further, the torque force loading device includes an asynchronous motor, a planetary gear reducer, a support, an end cover, a connecting shaft, an adapter, a positioning block and a rotating plunger. The asynchronous motor is fixed on the base plate and placed inside the support platform. The output end of the asynchronous motor is connected to the planetary gear reducer through a key, and the output end of the planetary gear reducer is connected to the connecting shaft, and the connecting shaft is connected to the lower end of the adapter. The adapter is provided with a groove matching the lower end of the positioning block, and the lower end of the positioning block is placed in the groove. A rotating plunger is provided on the side of the adapter, and the adapter and the positioning block are fixed by the rotating plunger.

[0016] The upper end of the planetary gear reducer is connected to the lower end of the support by bolts. The support is placed above the support platform. The connecting shaft and the torque sensor are placed in the support. The upper end of the support is fixed to the end cover by bolts, and the upper end of the connecting shaft passes through the end cover.

[0017] Furthermore, the torque loading device also includes a torque sensor. The asynchronous motor and the torque sensor are respectively connected to the data acquisition and control system. The torque sensor is installed on the connecting shaft and is used to obtain torque data in real time, and convert the force signal of the acquired torque data into an electrical signal, and send it to the data acquisition and control system. The torque data is processed and analyzed by the data acquisition and control system, and the asynchronous motor is driven to operate according to the size of the torque, so as to realize the loading and adjustment of the torque of the bolt to be tested.

[0018] The present invention also provides a test method of a high-strength bolt fatigue testing machine for TBM, which specifically comprises the following steps:

[0019] Step 1, sample preparation and installation:

[0020] Select the bolts to be tested, perform appearance inspection and dimension measurement on them to ensure they meet the test requirements;

[0021] Connect the upper fixture to the hydraulic push rod, connect the lower fixture to the upper end of the positioning block, control and adjust the height of the second column through the data acquisition and control system, thereby driving the middle beam and the upper fixture to move up and down, adjust the height of the upper fixture to match the bolt to be tested, fix the bolt to be tested between the upper fixture and the lower fixture through the bolt and nut to be tested, and use a torque wrench to twist the bolt and nut to be tested so that the preload force of the bolt to be tested reaches the expected value;

[0022] The end effector is controlled by the data acquisition and control system to close the lateral force fixture, so that the lateral force fixture clamps the bolt to be tested, thereby applying the lateral force to the bolt to be tested;

[0023] Step 2, installation of lateral force sensor, axial force sensor and torque force sensor:

[0024] The lateral force sensor is installed at the end of the power rod and connected to the data acquisition and control system; the axial force sensor is installed between the upper fixture and the bolt to be tested and connected to the data acquisition and control system; the torque force sensor is installed on the connecting shaft and connected to the data acquisition and control system;

[0025] Step 3, setting of test parameters:

[0026] According to the test requirements, the parameters are set on the data acquisition and control system, including the magnitude and frequency of the lateral force, the magnitude and frequency of the axial force, the magnitude and frequency of the torque force, the number of test cycles and the loading time;

[0027] Step 4, test start and run:

[0028] After confirming that the test parameter settings are correct, click the "Start" button on the data acquisition and control system to start the test machine; the data acquisition and control system controls the lateral force hydraulic cylinder, axial force hydraulic cylinder and asynchronous motor to start working, and drives the lateral force loading device, axial force loading device and torque force loading device to apply lateral force, axial force and torque force to the bolt to be tested according to the parameters set in step 3;

[0029] During the test, the lateral force sensor, axial force sensor and torque force sensor send the real-time acquired lateral force data, axial force data and torque force data to the data acquisition and control system for analysis and processing;

[0030] Step 5, data collection and analysis:

[0031] The data acquisition and control system draws stress-strain curves and displacement-time curves based on the acquired lateral force data, axial force data and torque force data. The operator views the test data and curves in real time. When the test reaches the set number of cycles or fatigue failure occurs in the bolt to be tested, the data acquisition and control system automatically controls the lateral force hydraulic cylinder, axial force hydraulic cylinder and asynchronous motor to stop moving, stops loading lateral force, axial force and torque on the bolt to be tested, and saves the test data. The operator analyzes and processes the saved data to evaluate the fatigue performance of the high-strength bolts.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The high-strength bolt fatigue testing machine for TBM of the present invention can simultaneously apply lateral force, axial force and torque force to the bolt to be tested. Compared with the prior art test equipment that only applies axial force or torque force, the present invention can truly simulate the complex stress environment of the high-strength bolt under the actual working state, and can realize precise adjustment of the magnitude and direction of the force through the data acquisition and control system, which significantly improves the accuracy and reliability of the test results and makes the test process more intelligent.

[0034] (2) The present invention can comprehensively evaluate the fatigue life and reliability of the bolt under complex stress conditions by intelligently simulating the interaction of multiple loads, thus providing a more reliable basis for the design, manufacture and application of high-strength bolts.

[0035] (3) The present invention adopts an automated control system, which is easy to operate and provides accurate test results. This intelligent control system enables the equipment to have multifunctional testing capabilities and can automatically adapt to the research and development and quality control requirements of different types of high-strength bolt products, greatly improving the test efficiency and intelligence level.

[0036] (4) The present invention has important application value in engineering fields such as TBM. Its intelligent and multifunctional characteristics enable it to efficiently evaluate the fatigue life and reliability of high-strength bolts, and it has broad application prospects and market value. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of a high-strength bolt fatigue testing machine for TBM provided by the present invention;

[0038] Figure 2 It is a structural schematic diagram of a torque force loading device of a high-strength bolt fatigue testing machine for TBM provided by the present invention;

[0039] Figure 3 It is a structural top view of a lateral force loading device of a high-strength bolt fatigue testing machine for TBM provided by the present invention;

[0040] Figure 4 It is a schematic diagram of the connection structure between the end effector and the lateral force clamp of a high-strength bolt fatigue testing machine for TBM provided by the present invention, wherein the lateral force clamp is in a closed state;

[0041] Figure 5 It is a schematic diagram of the connection structure between the end effector and the lateral force clamp of a high-strength bolt fatigue testing machine for TBM provided by the present invention, wherein the lateral force clamp is in an open state;

[0042] Figure 6 It is a structural schematic diagram of an axial force loading device of a high-strength bolt fatigue testing machine for TBM provided by the present invention;

[0043] Figure 7 It is a structural schematic diagram of a clamp device of a high-strength bolt fatigue testing machine for TBM provided by the present invention;

[0044] Figure 8 It is a schematic diagram of the internal structure of a second column of a high-strength bolt fatigue testing machine for TBM provided by the present invention;

[0045] Description of the accompanying drawings: 1. Base plate, 2. Support platform, 3. First column, 4. End effector, 401. Cylinder, 402. Telescopic rod, 5. Transverse force piston rod, 6. Transverse force hydraulic cylinder, 7. Fixed seat, 8. Power rod, 9. Transverse force sensor, 10. Transverse force clamp, 101. Clamping claw, 1011. Semicircular through hole, 102. Connecting arm, 103. Fixed plate, 104. Locking nut, 11. Hydraulic push rod, 12. Axial force hydraulic cylinder, 13. Middle beam, 14. Second column Column, 141. External column, 142. Internal telescopic column, 143. Height-adjusting hydraulic cylinder, 144. Height-adjusting piston rod, 15. Upper fixture, 16. Axial force sensor, 17. Bolts to be tested, 18. Bolts and nuts to be tested, 19. Lower fixture, 20. Positioning block, 21. Rotating plunger, 22. Adapter, 23. End cover, 24. Torque sensor, 25. Connecting shaft, 26. Support, 27. Planetary gear reducer, 28. Asynchronous motor, 29. Data acquisition and control system. DETAILED DESCRIPTION

[0046] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] Embodiment 1

[0048] Reference Figure 1 - Figure 8 A high-strength bolt fatigue testing machine for TBM includes a base plate 1, a support platform 2, a first column 3, a second column 14, a lateral force loading device, an axial force loading device, a torque loading device, an upper clamp 15, a lower clamp 19, a bolt to be tested 17, a bolt nut to be tested 18 and a data acquisition and control system 29. The base plate 1 is provided with a first column 3 and a second column 14 along the vertical direction, a support platform 2 is provided in front of the second column 14, a fixing seat 7 and a lateral force loading device are installed on the first column 3, and the second column 14 is a retractable structure. The top end of the second column 14 is fixed to the middle beam 13, the lower end of the middle beam 13 is connected to the axial force loading device, the lower end of the axial force loading device is connected to the upper fixture 15, the torque loading device is installed on the base plate 1 in the vertical direction, and is connected to the support platform 2, the upper end of the torque loading device is connected to the lower fixture 19, the upper and lower ends of the bolt 17 to be tested are respectively fixed to the bottom end of the upper fixture 15 and the top end of the lower fixture 19 through the bolt nut 18 to be tested, and the lateral force loading device is connected to the bolt 17 to be tested between the upper fixture 15 and the lower fixture 19;

[0049] The lateral force loading device applies a lateral force to the bolt 17 to be tested, so as to realize the loading of the lateral force on the bolt 17 to be tested;

[0050] The axial force loading device applies an axial force to the upper clamp 15, and the upper clamp 15 and the lower clamp 19 work together to transmit the axial force to the bolt 17 to be tested, thereby achieving the loading of the axial force of the bolt 17 to be tested;

[0051] The torque force loading device applies torque force to the lower clamp 19 to achieve torque force loading on the bolt 17 to be tested;

[0052] The lateral force loading device, axial force loading device, and torque force loading device are respectively connected to the data acquisition and control system 29, and the lateral force, axial force, and torque force data applied to the bolt 17 to be tested are obtained through the data acquisition and control system 29, and the actions of the lateral force loading device, axial force loading device, and torque force loading device are controlled.

[0053] The lateral force loading device includes a lateral force hydraulic cylinder 6, a lateral force piston rod 5, a power rod 8, an end actuator 4 and a lateral force clamp 10. The lateral force hydraulic cylinder 6 is fixed on the first column 3, and the fixed end of the lateral force hydraulic cylinder 6 is connected to the fixed seat 7. The telescopic end of the lateral force hydraulic cylinder 6 is connected to the power rod 8 through the lateral force piston rod 5. The other end of the power rod 8 is connected to the end actuator 4. The end actuator 4 is used to control the opening and closing of the lateral force clamp 10. When the end actuator 4 controls the lateral force clamp 10 to close, the lateral force clamp 10 clamps the bolt 17 to be tested. The lateral force hydraulic cylinder 6 drives the lateral force piston rod 5 to reciprocate in the horizontal direction, thereby driving the power rod 8, the end actuator 4 and the lateral force clamp 10 to reciprocate in the horizontal direction, so as to realize the loading of the lateral force on the bolt 17 to be tested and the adjustment of the size of the lateral force; after completing the fatigue test, the end actuator 4 controls the lateral force clamp 10 to open and releases the clamping force on the bolt 17 to be tested.

[0054] The end effector includes a cylinder 401 and a telescopic rod 402, the output end of the cylinder 401 is connected to the telescopic rod 402, the lateral force clamp 10 includes two clamping jaws 101, two connecting arms 102, a fixing plate 103 and a locking nut 104, the fixing plate 103 is fixed to the front end of the telescopic rod 402 by the locking nut 104, and the fixing plate 103 is perpendicular to the telescopic rod 402, connecting arms 102 are hinged at both ends of the fixing plate 103, and the other end of each connecting arm 102 is hinged to the clamping jaw 101, and the ends of the two clamping jaws 101 are hinged to the cylinder 401 respectively; the cylinder 401 is connected to the data acquisition and control system 29, and the data acquisition and control system 29 controls the movement of the cylinder 401, and drives the telescopic rod 402 to move forward and backward in the horizontal direction through the cylinder 401, thereby driving the two connecting arms 102 to rotate along the two ends of the fixing plate 103, so as to realize the closing and opening of the two clamping jaws 101.

[0055] A semicircular through hole 1011 is provided on the inner side of the front end of the clamping jaw 101. When the two clamping jaws 101 are closed, the two semicircular through holes 1011 are connected to form a circular through hole. The inner diameter of the circular through hole matches the outer diameter of the bolt 17 to be tested, thereby clamping the bolt 17 to be tested.

[0056] The lateral force loading device also includes a lateral force sensor 9. The lateral force hydraulic cylinder 6 and the lateral force sensor 9 are respectively connected to the data acquisition and control system 29. The lateral force sensor 9 is installed at the end of the power rod 8. The lateral force sensor 9 is used to obtain lateral force data in real time, and convert the force signal of the lateral force data into an electrical signal, and send it to the data acquisition and control system 29. The lateral force data is processed and analyzed by the data acquisition and control system 29, and the lateral force hydraulic cylinder 6 is controlled according to the size of the lateral force to drive the lateral force piston rod 5 to move, thereby realizing the loading and adjustment of the lateral force of the bolt 17 to be tested.

[0057] The axial force loading device includes an axial force hydraulic cylinder 12 and a hydraulic push rod 11. The axial force hydraulic cylinder 12 is fixed on the middle beam 13. The top of the hydraulic push rod 11 is connected to the axial force hydraulic cylinder 12, and the other end is connected to the top of the upper clamp 15. The axial force hydraulic cylinder 12 drives the hydraulic push rod 11 to move up and down in the axial direction, thereby applying axial force to the upper clamp 15. The upper clamp 15 and the lower clamp 19 work together to transmit the axial force to the bolt to be tested 17, thereby realizing the loading of the axial force of the bolt to be tested 17.

[0058] The center of the axial force hydraulic cylinder 12 in the axial force loading device, the center of the upper clamp 15 and the center of the lower clamp 19 are collinear in the vertical direction.

[0059] The axial force loading device also includes an axial force sensor 16. The axial force hydraulic cylinder 12 and the axial force sensor 16 are respectively connected to the data acquisition and control system 29. The axial force sensor 16 is installed at the connection between the lower end of the upper clamp 15 and the bolt 17 to be tested. The axial force sensor 16 is used to obtain axial force data in real time, and convert the force signal of the obtained axial force data into an electrical signal, and send it to the data acquisition and control system 29. The axial force data is processed and analyzed by the data acquisition and control system 29, and the axial force hydraulic cylinder 12 is driven to move according to the size of the axial force, so as to realize the loading and adjustment of the axial force of the bolt 17 to be tested.

[0060] The torque force loading device includes an asynchronous motor 28, a planetary gear reducer 27, a support 26, an end cover 23, a connecting shaft 25, an adapter 22, a positioning block 20 and a rotating plunger 21. The asynchronous motor 28 is fixed on the base plate 1 and placed inside the support platform 2. The output end of the asynchronous motor 28 is connected to the planetary gear reducer 27 through a key. The output end of the planetary gear reducer 27 is connected to the connecting shaft 25. The connecting shaft 25 is connected to the lower end of the adapter 22. The adapter 22 is provided with a groove matching the lower end of the positioning block 20. The lower end of the positioning block 20 is placed in the groove. A rotating plunger 21 is provided on the side of the adapter 22. The adapter 22 and the positioning block 20 are fixed by the rotating plunger 21.

[0061] The upper end of the planetary gear reducer 27 is connected to the lower end of the support 26 by bolts. The support 26 is placed above the support platform 2. The connecting shaft 25 and the torque sensor 24 are placed in the support 26. The upper end of the support 26 is fixed to the end cover 23 by bolts, and the upper end of the connecting shaft 25 passes through the end cover 23.

[0062] The torque loading device also includes a torque sensor 24. The asynchronous motor 28 and the torque sensor 24 are respectively connected to a data acquisition and control system 29. The torque sensor 24 is installed on a connecting shaft 25, and is used to obtain torque data in real time, and convert the force signal of the obtained torque data into an electrical signal, and send it to the data acquisition and control system 29. The torque data is processed and analyzed by the data acquisition and control system 29, and the asynchronous motor 28 is driven to operate according to the size of the torque, so as to realize the loading and adjustment of the torque of the bolt 17 to be tested.

[0063] Specifically, the second column 14 is a telescopic structure, and its height can be adjusted. By adjusting the height of the second column 14 , the height of the middle beam 13 is adjusted, and thus the height of the upper clamp 15 is adjusted.

[0064] Reference Figure 8 The second column 14 includes an outer column 141 and an inner telescopic column 142. A height-adjusting hydraulic cylinder 143 is provided inside the outer column 141. A height-adjusting piston rod 144 is provided on the height-adjusting hydraulic cylinder 143. The top of the height-adjusting piston rod 144 is fixed to the inner telescopic column 142. The height-adjusting hydraulic cylinder 143 is connected to the data acquisition and control system 29. The height-adjusting hydraulic cylinder 143 is controlled by the data acquisition and control system 29 to move, thereby driving the height-adjusting piston rod 144 to move up and down, driving the inner telescopic column 142 to move up and down in the outer column 141, thereby driving the middle beam 13 and the upper fixture 15 to move up and down, so as to adapt to the bolts 17 to be tested of different specifications.

[0065] Specifically, in the torque loading device, the function of the rotating plunger 21 is to transmit torque. When the asynchronous motor 28 is decelerated by the planetary gear reducer 27, the torque is transmitted to the adapter 22 through the connecting shaft 25. The rotating plunger 21 helps to transmit the torque from the adapter 22 to the positioning block 20, and then the positioning block 20 is transmitted to the lower clamp 19, thereby realizing the torque loading of the bolt 17 to be tested. At the same time, the rotating plunger 21 has an adjustment function. During the test, the relative position between the adapter 22 and the positioning block 20 is adjusted as needed to ensure the accuracy of torque transmission and the consistency of the test. When adjusted in place, the rotating plunger 21 locks the position to prevent displacement during the test.

[0066] Specifically, in the torque loading device, the end cover 23 is fixed on the support 26, and the fixing method between the end cover 23 and the support 26 is a bolt connection, which ensures that the end cover 23 remains fixed during the test without displacement or loosening. The support 26 and the planetary gear reducer 27 are connected by bolts. The support platform 2 is placed on the base plate 1, and the support 26 is placed on the support platform 2; the support platform 2 and the support 26 are load-bearing components, which prevent the entire weight of the loading device from being pressed on the planetary gear reducer 27 and the asynchronous motor 28, thereby ensuring the stability of the testing machine and extending the service life of key components.

[0067] Specifically, the data acquisition and control system 29 includes an industrial computer, a PLC controller and data acquisition software. The industrial computer serves as a human-computer interaction interface, and the operator sets the test parameters and controls the start and stop of the test machine on the industrial computer; the PLC controller controls the actions of the lateral force hydraulic cylinder 6, the axial force hydraulic cylinder 12 and the asynchronous motor 28 according to the instructions of the industrial computer to ensure that the test is carried out according to the set parameters; the data acquisition software has data acquisition and processing functions, and can collect data from the lateral force sensor 9, the axial force sensor 16 and the torque force sensor 24 in real time, and analyze and process them, such as drawing stress-strain curves, displacement-time curves, etc., to provide data support for evaluating the fatigue performance of the bolt 17 to be tested.

[0068] Embodiment 2

[0069] Reference Figure 1-Figure 8 A test method of a high-strength bolt fatigue testing machine for TBM is implemented by using the high-strength bolt fatigue testing machine for TBM described in the first embodiment, and specifically includes the following steps:

[0070] Step 1, sample preparation and installation:

[0071] Select a bolt 17 to be tested, perform appearance inspection and dimension measurement on the bolt 17 to ensure that it meets the test requirements;

[0072] The upper fixture 15 is connected to the hydraulic push rod 11, and the lower fixture 19 is connected to the upper end of the positioning block 20. The height of the second column 15 is controlled and adjusted by the data acquisition and control system 29 (the height adjustment hydraulic cylinder 143 is controlled by the data acquisition and control system 29 to drive the height adjustment piston rod 144 to move up and down, and the internal telescopic column 142 is driven to move up and down in the outer column 141), thereby driving the middle beam 13 and the upper fixture 15 to move up and down, and adjusting the height of the upper fixture 15 to match the tested bolt 17 to be tested, and then fixing the tested bolt 17 between the upper fixture 15 and the lower fixture 19 respectively through the tested bolt nut 18, and twisting the tested bolt nut 18 with a torque wrench to make the preload force of the tested bolt 17 reach the expected value;

[0073] The end effector 4 is controlled to move by the data acquisition and control system 29, and the lateral force clamp 10 is controlled to close, so that the lateral force clamp 10 clamps the bolt 17 to be tested, thereby applying the lateral force to the bolt 17 to be tested;

[0074] Step 2, installation of the lateral force sensor 9, the axial force sensor 16 and the torque force sensor 24:

[0075] The lateral force sensor 9 is installed at the end of the power rod 8 and connected to the data acquisition and control system 29; the axial force sensor 16 is installed between the upper fixture 15 and the bolt to be tested 17 and connected to the data acquisition and control system 29; the torque force sensor 24 is installed on the connecting shaft 25 and connected to the data acquisition and control system 29;

[0076] Step 3, setting of test parameters:

[0077] According to the test requirements, parameters are set on the data acquisition and control system 29, and the parameter settings include the magnitude and frequency of the lateral force, the magnitude and frequency of the axial force, the magnitude and frequency of the torque force, the number of test cycles, and the loading time;

[0078] Step 4, test start and run:

[0079] After confirming that the test parameter settings are correct, click the "Start" button on the data acquisition and control system 29 to start the test machine; the data acquisition and control system 29 controls the lateral force hydraulic cylinder 6, the axial force hydraulic cylinder 12 and the asynchronous motor 28 to start working, and respectively drives the lateral force loading device, the axial force loading device, and the torque force loading device to apply lateral force, axial force and torque force to the bolt 17 to be tested according to the parameters set in step 3;

[0080] During the test, the lateral force sensor 9, the axial force sensor 16 and the torque force sensor 24 send the lateral force data, axial force data and torque force data acquired in real time to the data acquisition and control system 29 for analysis and processing;

[0081] Step 5, data collection and analysis:

[0082] The data acquisition and control system 29 draws stress-strain curves and displacement-time curves based on the acquired lateral force data, axial force data and torque force data, and the operator views the test data and curves in real time. When the test reaches the set number of cycles or fatigue failure occurs in the bolt 17 to be tested, the data acquisition and control system 29 automatically controls the lateral force hydraulic cylinder 6, the axial force hydraulic cylinder 12 and the asynchronous motor 28 to stop action, stops loading the lateral force, axial force and torque force on the bolt 17 to be tested, and saves the test data. The operator can further analyze and process the saved data to evaluate the fatigue performance of the bolt 17 to be tested.

[0083] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, many changes can be made in the specific implementation methods and application scopes based on the ideas of the present invention. As long as these changes do not deviate from the concept of the present invention, they all belong to the protection scope of the present invention.

Claims

1. A high-strength bolt fatigue testing machine for TBM, characterized in that: It includes a base plate, a support platform, a first column, a second column, a lateral force loading device, an axial force loading device, a torque loading device, an upper fixture, a lower fixture, a bolt to be tested, a bolt nut to be tested and a data acquisition and control system, wherein the base plate is provided with a first column and a second column in a vertical direction, a support platform is provided in front of the second column, a fixing seat and a lateral force loading device are installed on the first column, the second column is a retractable structure, the top end of the second column is fixed to the middle beam, the lower end of the middle beam is connected to the axial force loading device, the lower end of the axial force loading device is connected to the upper fixture, the torque loading device is installed on the base plate in a vertical direction and is connected to the support platform, the upper end of the torque loading device is connected to the lower fixture, the upper and lower ends of the bolt to be tested are respectively fixed to the bottom end of the upper fixture and the top end of the lower fixture through the bolt nut to be tested, and the lateral force loading device is connected to the bolt to be tested between the upper fixture and the lower fixture; The lateral force loading device applies lateral force to the bolt to be tested, so as to realize the lateral force loading of the bolt to be tested; The axial force loading device applies axial force to the upper fixture, and the upper fixture and the lower fixture work together to transmit the axial force to the bolt to be tested, thereby realizing the loading of the axial force of the bolt to be tested; The torque force loading device applies torque force to the lower fixture to achieve torque force loading on the bolt to be tested; The lateral force loading device, the axial force loading device, and the torque force loading device are respectively connected to the data acquisition and control system, through which the lateral force, axial force, and torque force data applied to the bolt to be tested are obtained, and the actions of the lateral force loading device, the axial force loading device, and the torque force loading device are controlled; the data acquisition and control system is also connected to the second column to adjust the height of the second column.

2. A high-strength bolt fatigue testing machine for TBM according to claim 1, characterized in that: The lateral force loading device includes a lateral force hydraulic cylinder, a lateral force piston rod, a power rod, an end actuator and a lateral force clamp. The lateral force hydraulic cylinder is fixed on the first column, and the fixed end of the lateral force hydraulic cylinder is connected to the fixed seat. The telescopic end of the lateral force hydraulic cylinder is connected to the power rod through the lateral force piston rod, and the other end of the power rod is connected to the end actuator. The end actuator is used to control the opening and closing of the lateral force clamp. When the end actuator controls the lateral force clamp to close, the lateral force clamp clamps the bolt to be tested, and the lateral force hydraulic cylinder drives the lateral force piston rod to reciprocate in the horizontal direction, thereby driving the power rod, the end actuator and the lateral force clamp to reciprocate in the horizontal direction, thereby realizing the loading of the lateral force on the bolt to be tested and the adjustment of the size of the lateral force; after completing the fatigue test, the end actuator controls the lateral force clamp to open and releases the clamping force on the bolt to be tested.

3. A high-strength bolt fatigue testing machine for TBM according to claim 2, characterized in that: The end effector includes a cylinder and a telescopic rod, the output end of the cylinder is connected to the telescopic rod, the lateral force clamp includes two clamping jaws, two connecting arms, a fixed plate and a locking nut, the fixed plate is fixed to the front end of the telescopic rod by a locking nut, connecting arms are hinged at both ends of the fixed plate, the other end of each connecting arm is hinged to the clamping jaws, and the ends of the two clamping jaws are hinged to the cylinder respectively; the cylinder is connected to the data acquisition and control system, the data acquisition and control system controls the movement of the cylinder, and the telescopic rod is driven by the cylinder to move forward and backward in the horizontal direction, thereby driving the two connecting arms to rotate along the two ends of the fixed plate to realize the closing and opening of the two clamping jaws.

4. A high-strength bolt fatigue testing machine for TBM according to claim 3, characterized in that: A semicircular through hole is provided on the inner side of the front end of the clamping jaw. When the two clamping jaws are closed, the two semicircular through holes are butted together to form a circular through hole. The inner diameter of the circular through hole matches the outer diameter of the bolt to be tested, thereby clamping the bolt to be tested.

5. A high-strength bolt fatigue testing machine for TBM as claimed in claim 3, characterized in that: The lateral force loading device also includes a lateral force sensor. The lateral force hydraulic cylinder and the lateral force sensor are respectively connected to the data acquisition and control system. The lateral force sensor is installed at the end of the power rod. The lateral force sensor is used to obtain lateral force data in real time, and convert the force signal of the lateral force data into an electrical signal, and send it to the data acquisition and control system. The lateral force data is processed and analyzed by the data acquisition and control system, and the lateral force hydraulic cylinder is controlled to drive the lateral force piston rod to move according to the size of the lateral force, so as to realize the loading and adjustment of the lateral force of the bolt to be tested.

6. A high-strength bolt fatigue testing machine for TBM according to claim 1, characterized in that: The axial force loading device includes an axial force hydraulic cylinder and a hydraulic push rod. The axial force hydraulic cylinder is fixed on the middle beam. The top of the hydraulic push rod is connected to the axial force hydraulic cylinder, and the other end is connected to the top of the upper clamp. The axial force hydraulic cylinder drives the hydraulic push rod to move up and down in the axial direction, thereby applying axial force to the upper clamp. The upper clamp and the lower clamp work together to transmit the axial force to the bolt to be tested, thereby realizing the loading of the axial force of the bolt to be tested.

7. A high-strength bolt fatigue testing machine for TBM according to claim 6, characterized in that: The axial force loading device also includes an axial force sensor. The axial force hydraulic cylinder and the axial force sensor are respectively connected to the data acquisition and control system. The axial force sensor is installed at the connection between the lower end of the upper clamp and the bolt to be tested. The axial force sensor is used to obtain axial force data in real time, and convert the force signal of the obtained axial force data into an electrical signal, and send it to the data acquisition and control system. The axial force data is processed and analyzed by the data acquisition and control system, and the axial force hydraulic cylinder is driven to move according to the size of the axial force, so as to realize the loading and adjustment of the axial force of the bolt to be tested.

8. A high-strength bolt fatigue testing machine for TBM according to claim 1, characterized in that: The torque force loading device includes an asynchronous motor, a planetary gear reducer, a support, an end cover, a connecting shaft, an adapter, a positioning block and a rotating plunger. The asynchronous motor is fixed on the bottom plate and placed inside the support platform. The output end of the asynchronous motor is connected to the planetary gear reducer through a key, and the output end of the planetary gear reducer is connected to the connecting shaft, and the connecting shaft is connected to the lower end of the adapter. The adapter is provided with a groove matching the lower end of the positioning block, and the lower end of the positioning block is placed in the groove. A rotating plunger is provided on the side of the adapter, and the adapter and the positioning block are fixed by the rotating plunger. The upper end of the planetary gear reducer is connected to the lower end of the support by bolts. The support is placed above the support platform. The connecting shaft and the torque sensor are placed in the support. The upper end of the support is fixed to the end cover by bolts, and the upper end of the connecting shaft passes through the end cover.

9. A high-strength bolt fatigue testing machine for TBM according to claim 8, characterized in that: The torque loading device also includes a torque sensor. The asynchronous motor and the torque sensor are respectively connected to the data acquisition and control system. The torque sensor is installed on the connecting shaft and is used to obtain torque data in real time, and convert the force signal of the acquired torque data into an electrical signal, and send it to the data acquisition and control system. The torque data is processed and analyzed by the data acquisition and control system, and the asynchronous motor is driven to move according to the size of the torque, so as to realize the loading and adjustment of the torque of the bolt to be tested.

10. The test method of the high-strength bolt fatigue testing machine for TBM according to any one of claims 1 to 9, characterized in that: The specific steps include: Step 1, sample preparation and installation: Select the bolts to be tested, perform appearance inspection and dimension measurement on them to ensure they meet the test requirements; Connect the upper fixture to the hydraulic push rod, connect the lower fixture to the upper end of the positioning block, control and adjust the height of the second column through the data acquisition and control system, thereby driving the middle beam and the upper fixture to move up and down, adjust the height of the upper fixture to match the bolt to be tested, fix the bolt to be tested between the upper fixture and the lower fixture through the bolt and nut to be tested, and use a torque wrench to twist the bolt and nut to be tested so that the preload force of the bolt to be tested reaches the expected value; The end effector is controlled by the data acquisition and control system to close the lateral force fixture, so that the lateral force fixture clamps the bolt to be tested, thereby applying the lateral force to the bolt to be tested; Step 2, installation of lateral force sensor, axial force sensor and torque force sensor: The lateral force sensor is installed at the end of the power rod and connected to the data acquisition and control system; the axial force sensor is installed between the upper fixture and the bolt to be tested and connected to the data acquisition and control system; the torque force sensor is installed on the connecting shaft and connected to the data acquisition and control system; Step 3, setting of test parameters: According to the test requirements, the parameters are set on the data acquisition and control system, including the magnitude and frequency of the lateral force, the magnitude and frequency of the axial force, the magnitude and frequency of the torque force, the number of test cycles and the loading time; Step 4, test start and run: After confirming that the test parameter settings are correct, click the "Start" button on the data acquisition and control system to start the test machine; the data acquisition and control system controls the lateral force hydraulic cylinder, axial force hydraulic cylinder and asynchronous motor to start working, and drives the lateral force loading device, axial force loading device and torque force loading device to apply lateral force, axial force and torque force to the bolt to be tested according to the parameters set in step 3; During the test, the lateral force sensor, axial force sensor and torque force sensor send the real-time acquired lateral force data, axial force data and torque force data to the data acquisition and control system for analysis and processing; Step 5, data collection and analysis: The data acquisition and control system draws stress-strain curves and displacement-time curves based on the acquired lateral force data, axial force data and torque force data. The operator views the test data and curves in real time. When the test reaches the set number of cycles or fatigue failure occurs in the bolt to be tested, the data acquisition and control system automatically controls the lateral force hydraulic cylinder, axial force hydraulic cylinder and asynchronous motor to stop moving, stops loading lateral force, axial force and torque on the bolt to be tested, and saves the test data. The operator analyzes and processes the saved data to evaluate the fatigue performance of the high-strength bolts.

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