A multi-angle fillet weld based stress testing system

Abstract

A stress testing system based on multi-angle fillet welds comprises an ultrasonic stress probe assembly, an ultrasonic signal processing system, a pressure guide rod mechanism, a multi-axis translation device and a central processing system; the ultrasonic stress probe assembly comprises a transmitting end and a receiving end, respectively emits and receives ultrasonic vibration signals, and is used for measuring the internal residual stress of a measured workpiece; the ultrasonic signal processing system is used for processing ultrasonic measurement signals, calculating and analyzing stress data; the pressure guide rod mechanism is used for smoothly placing the ultrasonic stress probe assembly on the surface of the workpiece, detecting the contact condition and keeping the working pressure during testing; the multi-axis translation device is used for moving the stress testing system along a preset track; and the central processing system is used for receiving and processing the calculation results of the ultrasonic signal processing system, and synchronously controlling the mechanical actions of the multi-axis translation device and the pressure guide rod mechanism. The application has the characteristics of high detection efficiency of the residual stress of multi-angle welds.

Description

Technical Field

[0001] This invention belongs to the technical field of stress testing systems, and specifically relates to a stress testing system based on multi-angle fillet welds. Background Technology

[0002] Residual stress is an elastic stress that maintains equilibrium within a material due to uneven plastic deformation. It arises from the combined effects of uneven elastic-plastic deformation, temperature changes, and phase transformations within the material itself. While residual stress is unavoidable during various physical or chemical processing steps, it is particularly problematic in welding processes, especially for large welded components. Welding residual stress can lead to deformation or cracking, affecting the overall structural dimensions and even the material's robustness. Therefore, stress measurement of the weld seam and surrounding material of critical welded workpieces is an essential inspection step.

[0003] The main methods for testing residual stress currently include blind hole method, ring core method, X-ray diffraction method, center diffraction method, and ultrasonic detection method. Among these, the blind hole method and ring core method are destructive to the workpiece being tested; while X-ray diffraction method and center diffraction method require sophisticated equipment and are complex and difficult to implement. For example, US2021055173A and CN111366281(A) disclose some of the latest testing methods to provide more options in the testing field; while US2021069828(A1), CN206732346(U), and US2021069813(A1) are also researching methods to improve welding technology and related equipment.

[0004] However, most of the currently available technologies are based on the measurement of residual stress at fixed points. For workpieces with multi-angle welds, the shape of the workpiece changes, and the positioning and adjustment of the corresponding testing equipment will require a lot of manpower and time, as well as a little more repetitive operation time. Summary of the Invention

[0005] In order to overcome the problems existing in the prior art, the purpose of this invention is to provide a stress testing system based on multi-angle fillet welds, which has the characteristics of high detection efficiency for residual stress in multi-angle welds.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A stress testing system based on multi-angle fillet welds includes an ultrasonic stress probe assembly 101, an ultrasonic signal processing system 504, a pressure guide rod mechanism 103, a multi-axis translation device, and a central processing system 102.

[0008] The ultrasonic stress probe assembly 101 includes a transmitter and a receiver, which respectively emit and receive ultrasonic vibration signals to measure the internal residual stress of the workpiece 503 under test.

[0009] The ultrasonic signal processing system 504 is used to process ultrasonic measurement signals and calculate and analyze stress data.

[0010] The pressure guide rod mechanism 103 is used to smoothly place the ultrasonic stress probe assembly 101 onto the workpiece surface, detect the contact situation, and maintain the working pressure during the test.

[0011] The multi-axis translation device is used to move this stress testing system along a preset trajectory;

[0012] The central processing system 102 is used to receive and process the calculation results of the ultrasonic signal processing system 504, and synchronously control the mechanical actions of the multi-axis translation device and the pressure guide rod mechanism 103.

[0013] The transmitting end assembly includes an ultrasonic transmitting terminal and a transmitting end lens 502. The transmitting terminal is used to transmit ultrasonic signals 504 with high concentration and precise directionality. The transmitting end lens 502 ensures that the incident angle of the ultrasonic wave conforms to the first critical angle of refraction for a specific workpiece 503 under test. The transmitting end lens 502 has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the transmitting terminal. The transmitting end lens 502 serves as a propagation medium, allowing the ultrasonic signal 504 from the transmitting terminal to pass through it with low energy consumption and low scattering rate. The receiving end assembly includes an ultrasonic receiving terminal and a receiving end lens. The receiving terminal is used to directionally receive the ultrasonic signal 504. The receiving end lens has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the receiving terminal. The receiving end lens serves as a propagation medium, allowing the ultrasonic signal 504 to pass through it with low energy consumption and low scattering rate, and ensuring that the ultrasonic signal 504 is accurately directed towards the receiving terminal.

[0014] The ultrasonic signal processing system 504 is connected to an ultrasonic transmitting terminal and an ultrasonic receiving terminal. The ultrasonic signal processing system 504 includes an ultrasonic transducer, an ultrasonic controller, and an excitation power supply. The ultrasonic controller controls the excitation power supply to provide the ultrasonic transducer with the required electrical energy. The ultrasonic transducer generates ultrasonic waves by converting electrical energy. The ultrasonic controller can precisely control the power and frequency of the required ultrasonic waves and maintain them for a certain period of time. The ultrasonic signal processing system 504 can receive electrical signals from the ultrasonic receiving terminal and process them into electrical signals that can be recognized by a computer.

[0015] The pressure-applying guide rod mechanism 103 is installed above the ultrasonic stress probe assembly 101, pushing the ultrasonic stress probe assembly 101 toward the surface of the workpiece 503 to be tested and applying appropriate pressure; the pressure-applying guide rod mechanism 103 includes a precision electric cylinder, a pressure-sensitive sensor and a communication module.

[0016] The precision electric cylinder uses electrical signals to control the sliding displacement of the front end of the cylinder and the driving force; the pressure sensor is used to detect the contact pressure between the ultrasonic stress probe assembly 101 and the workpiece 503 under test; the communication module is used to receive the detection data of the pressure sensor and send it to the central processing system 102, and to receive the control signal of the precision electric cylinder from the central processing system 102.

[0017] The connection between the pressure guide rod mechanism 103 and the ultrasonic stress probe assembly 101 has a rotation fine-tuning device 109. The rotation fine-tuning device 109 is used to control the angle of fine-tuning according to the reading of the pressure sensor by the central control system, so that the ultrasonic stress probe is pressed evenly onto the surface of the workpiece 503 being tested.

[0018] The multi-axis translation device includes a left support portion 104 and a right support portion 108; the left support portion 104 and the right support portion 108 have sliding or rolling movement mechanisms for linear movement in a human-oriented or track-guided manner; the left support portion 104 and the right support portion 108 have connecting components.

[0019] The connecting parts are connected by one or more casters or casters, and the right support 108 and the left support 104 can rotate around each other at a certain angle; the connecting parts of the left and right support parts 108 are locked or their relative rotation angle is slowly changed with damping, so that the left support 104 and the right support 108 can be stably fixed and relatively stationary at a preset deflection angle.

[0020] The multi-axis translation device mounts one or more ultrasonic stress probe assemblies 101 and one or more pressure sliding rod mechanisms onto the multi-axis translation device structure; the multi-axis translation device has braking capability and can maintain a stable static posture on a plane or inclined plane.

[0021] The multi-axis translation device includes a drive device 106, which is a linear motor or a servo motor, or other power source device that drives the multi-axis translation device to move.

[0022] The central processing system 102 includes a memory, a processor, and instructions stored in the memory and executable on the processor. The central processing system 102 can read and modify data recorded in the memory and execute computer programs. The central processing system 102 is connected to the ultrasonic signal processing system 504 and the multi-axis translation device, and can communicate with them. The memory includes random access memory and erasable memory. The random access memory is used for temporary data caching and awaits data to be written to the erasable memory. The erasable memory can repeatedly update the data stored internally, and for computer programs, it can be manually updated to change the execution logic and algorithms specified by the program.

[0023] The beneficial effects of this invention are:

[0024] 1. Improve the accuracy of testing by using ultrasonic stress testing method;

[0025] 2. By using detection units in two parts, left and right, the residual stress of the workpiece on both sides of the weld can be detected simultaneously and a corresponding comparison can be made to provide more judgment data and technical personnel.

[0026] 3. By adopting an active and continuous structural design, the detection unit can be flexibly arranged at multiple angles for different welds, greatly improving the adaptability of the detection.

[0027] 4. By employing a power-driven moving mechanism in conjunction with an electronic control system, the system of the present invention can automatically detect workpieces of relatively long lengths;

[0028] 5. By employing pressure sensors and electronic systems in conjunction with monitoring, the reliability of measurement data is ensured;

[0029] 6. By employing database recording and incorporating computer programs, large-scale and continuous data collection can be achieved to provide data for future analysis and research; and data can be organized to generate graphical tables or images for technicians to analyze test results more clearly and intuitively. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall device of the present invention.

[0031] Figure 2 This is a schematic diagram showing the coordinate positioning of the workpiece being measured.

[0032] Figure 3 This is a schematic diagram of the workflow of the present invention.

[0033] Figure 4 This is a schematic diagram of the ultrasonic stress probe assembly.

[0034] Figure 5 This is a schematic diagram illustrating the principle of ultrasonic stress testing.

[0035] Figure 6 This is a schematic diagram showing the coordination and testing of the stress testing system for the multi-angle fillet weld with the rail.

[0036] Figure 7 This is a schematic diagram of the stress detection result curve.

[0037] Figure 8 This is a schematic diagram of the stress detection results.

[0038] Explanation of reference numerals: 101-Ultrasonic stress probe assembly; 102-Central processing system; 103-Pressure guide rod mechanism; 104-Left support; 105-Guide wheel; 106-Drive device; 107-Universal connector; 108-Right support; 109-Rotation fine adjustment device; 501-Ultrasonic wave transmitting terminal; 502-Transmitting lens; 503-Workpiece under test; 504-Ultrasonic signal; 505-Ultrasonic critical refraction longitudinal wave. Detailed Implementation

[0039] The present invention will now be described in further detail with reference to the accompanying drawings.

[0040] Example 1:

[0041] See appendix Figure 1 A stress testing system based on multi-angle fillet welds is disclosed. The system includes: an ultrasonic stress probe assembly 101, an ultrasonic signal processing system 504, a pressure guide rod mechanism 103, a multi-axis translation device, and a central processing system 102. The ultrasonic stress probe includes a transmitting end and a receiving end, which respectively emit and receive ultrasonic vibration signals to measure the residual stress inside the workpiece 503. The ultrasonic signal processing system 504 processes the ultrasonic measurement signals and calculates and analyzes stress data. The pressure guide rod mechanism smoothly places the ultrasonic stress probe assembly 101 onto the workpiece surface, detects contact, and maintains the working pressure during testing. The multi-axis translation device moves the stress testing system along a preset trajectory. The central processing system 102 receives and processes the calculation results of the ultrasonic signal processing system 504 and synchronously controls the mechanical movements of the multi-axis translation device and the pressure guide rod mechanism 103.

[0042] The ultrasonic stress probe assembly 101 includes a transmitting end assembly and a receiving end assembly. The transmitting end assembly includes an ultrasonic transmitting terminal and a transmitting end lens 502. The transmitting terminal is used to transmit ultrasonic signals 504 with high concentration and precise directionality. The transmitting end lens 502 ensures that the incident angle of the ultrasonic wave conforms to the first critical angle of refraction for a specific workpiece 503 under test. The transmitting end lens 502 has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the transmitting terminal. The transmitting end lens 502 serves as a propagation medium, allowing the ultrasonic signal 504 from the transmitting terminal to pass through it with low energy consumption and low scattering rate. The receiving end assembly includes an ultrasonic receiving terminal and a receiving end lens. The receiving terminal is used to directionally receive the ultrasonic signal 504. The receiving end lens has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the receiving terminal. The receiving end lens serves as a propagation medium, allowing the ultrasonic signal 504 to pass through it with low energy consumption and low scattering rate, and ensuring that the ultrasonic signal 504 is accurately directed towards the receiving terminal.

[0043] The ultrasonic signal processing system 504 is connected to the ultrasonic transmitting terminal and the ultrasonic receiving terminal. The ultrasonic signal processing system 504 includes an ultrasonic transducer, an ultrasonic controller, and an excitation power supply. The ultrasonic controller controls the excitation power supply to provide the ultrasonic transducer with the required electrical energy. The ultrasonic transducer generates ultrasonic waves by converting electrical energy. The ultrasonic controller can precisely control the power and frequency of the required ultrasonic waves and maintain them for a certain period of time. The ultrasonic signal processing system 504 can receive electrical signals from the ultrasonic receiving terminal and process them into electrical signals that can be recognized by a computer.

[0044] The pressure-applying guide rod mechanism 103 is mounted above the ultrasonic stress probe assembly 101, pushing the ultrasonic stress probe assembly 101 towards the surface of the workpiece 503 and applying appropriate pressure. The pressure-applying guide rod mechanism 103 includes a precision electric cylinder, a pressure-sensitive sensor, and a communication module. The precision electric cylinder uses electrical signals to control the sliding displacement of its front end and the driving force. The pressure-sensitive sensor is used to detect the contact pressure between the ultrasonic stress probe assembly 101 and the workpiece 503. The communication module is used to receive the detection data from the pressure-sensitive sensor and send it to the central processing system 102, as well as to receive control signals from the central processing system 102 for the precision electric cylinder. The connection between the pressure-applying guide rod mechanism 103 and the ultrasonic stress probe assembly 101 has a rotation fine-tuning device 109, which is used to control the fine-tuning angle by the central control system according to the reading of the pressure-sensitive sensor, so that the ultrasonic stress probe is pressed evenly onto the surface of the workpiece 503.

[0045] The multi-axis translation device includes left and right support portions 108; both left and right support portions 108 are configured with sliding or rolling movement mechanisms for linear movement in a human-oriented or track-guided manner; the left and right support portions 108 have connecting components; the connecting components are connected by one or more casters or caster bearings, and are configured such that the right support portion 108 and the left support portion 104 can rotate relative to each other by a certain angle; the connecting components of the left and right support portions 108 are locked or their relative rotation angle is slowly changed with damping, so that the left and right support portions 108 can be stably fixed at a preset deflection angle and remain relatively stationary;

[0046] The central processing system 102 includes a memory, a processor, and instructions stored in the memory and executable on the processor. The central processing system 102 can read and modify data recorded in the memory and execute computer programs. The central processing system 102 is connected to the ultrasonic signal processing system 504 and the multi-axis translation device, and can communicate with them. The memory includes random access memory and erasable memory. The random access memory is used for temporary data caching and awaits data to be written to the erasable memory. The erasable memory can repeatedly update the data stored internally, and for the computer program, manual updates can be used to change the execution logic and algorithms specified by the program.

[0047] The multi-axis translation device mounts one or more ultrasonic stress probe assemblies 101 and one or more pressure sliding rod mechanisms onto the multi-axis translation device structure; the multi-axis translation device has braking capability and can maintain a stable static posture on a plane or inclined plane.

[0048] The multi-axis translation device includes a drive device 106; the drive device 106 may include a linear motor, a servo motor, or other power source device that drives the multi-axis translation device to move.

[0049] At the start of the measurement, the stress testing system for the multi-angle fillet weld is placed on the two welded parts of the workpiece 503 under test, and the distribution points of the test points are marked according to the extension direction of the weld; after starting the device, the following steps are performed. Figure 3 The process;

[0050] The multi-axis translation mechanism sets the drive device 106 to a stationary and locked state, ensuring that the stress testing system is stationary at the predetermined measurement point. The left and right support portions 108 are adaptively adjusted according to the specific welding angle of the workpiece, aiming to ensure that both the left and right support portions 108 can stably contact the workpiece 503 under test without relative sliding. One or more pressure-applying guide rod mechanisms 103 extend towards the workpiece 503 under test, pressing the ultrasonic stress probe assembly 101 against the measurement point #1 of the workpiece 503. The pressure-applying guide rod mechanism 103 can rotate in the z-axis direction to measure the stress value at a preset plane angle θ. Multiple pressure sensors begin measuring the pressure between the ultrasonic stress probe assembly 101 and the workpiece 503 under test, ensuring good and tight contact between the lens and the surface of the measurement point #1 of the workpiece 503 under appropriate contact pressure. The pressure-applying guide rod mechanism 103 checks the contact pressures F1, F2…Fn of the multiple pressure sensors and ensures that the following two equations are satisfied:

[0051] Formula 1-1: F1 <F p &&F2 <F P &&……F n <F p ;

[0052] Formula 1-2:

[0053] In Formula 1-1, Fp is the pressure limit threshold to prevent excessive contact pressure from causing additional load on the workpiece 503 under test, thereby generating internal stress error; in Formula 1-2, σ p The standard deviation of all pressure-sensitive sensor readings can be obtained experimentally on a specific material surface. Its function is to ensure that the ultrasonic stress probe assembly 101 can make uniform contact with the surface of the workpiece 503 being tested.

[0054] After the ultrasonic stress probe assembly 101 completes the pressure application, the ultrasonic signal processing system 504 begins to emit ultrasonic waves. According to Snell's theory of light refraction, when the ultrasonic wave is passed through the lens and refracted into the workpiece 503 using the transmitting end assembly, the ultrasonic critical refracted longitudinal wave 505 (hereinafter abbreviated as L) generated by the refraction of the ultrasonic wave... CR The wave will propagate along the xy plane direction of the workpiece 503 being measured; when L CR When a wave propagates over a fixed distance in the workpiece 503, the residual stress in the workpiece is linearly related to the speed of sound wave propagation. Assuming the workpiece 503 is under zero stress, the following formula applies:

[0055] Formula 2-1:

[0056] Where s is the fixed distance in the test; t0 is the time it takes for the ultrasonic wave to travel through s, or simply acoustic time; v0 is the propagation speed of the ultrasonic wave in the specific material 503 of the workpiece being tested.

[0057] When residual stress exists inside the workpiece 503 under test, and without the influence of external load, its acoustic time will change accordingly, that is,

[0058] Formula 2-2: t1 = t0 + Δt,

[0059] Where t1 is the acoustic time of the ultrasonic wave propagating a distance s in the workpiece 503 under residual stress, and Δt is the acoustic time difference caused by residual stress, the sign of which can be positive or negative; according to elasticity, the following results are obtained:

[0060] Formula 2-3: Δσ=K·Δt,

[0061] Where Δσ is the difference in internal stress of the workpiece 503 being measured, which is the residual stress to be calculated. The sign of Δσ can be positive or negative, representing tensile stress and compressive stress respectively; K is the elastic constant of the material.

[0062] The ultrasonic signal processing system 504 accurately measures the acoustic time value and submits it to the central processing system 102 for statistical analysis. Simultaneously, since the temperature during the measurement process can cause stress drift in the measured workpiece 503, temperature compensation calculations need to be added to formula 2-2.

[0063] Formula 42-: Δt=t1-t0-t tp ,

[0064] Where t tp For specific materials, the time-temperature compensation value is set; the central processing system 102 can set t based on temperature sensor data or temperature data input by the measuring personnel. tp The value;

[0065] The central processing system 102 records the stress value Δσ1 at measurement point #1 and the measurement value Δσ'1 at measurement point #1' on the two welding surfaces, and stores the measurement data in the memory; the operator moves the stress testing system of the multi-angle fillet weld to the next measurement point #2 and repeats the above measurement process;

[0066] After completing measurements at n measurement points, the central processing system 102 can present the final results in the form of charts or data tables; see appendix. Figure 7If the measured value of a certain measurement point #m is found to deviate too much from the measurement curve, the system will issue a prompt, and the staff will re-check the value of the measurement point #m. If necessary, the measurement operation will be performed again. Furthermore, if the value is confirmed to be correct, it can be determined that there is a process defect in the weld position corresponding to the point, and further inspection is required.

[0067] Example 2:

[0068] This embodiment should be understood to include at least all the features of any of the foregoing embodiments, and to further improve upon them; it provides a stress testing system based on multi-angle fillet welds, the stress testing system comprising: an ultrasonic stress probe assembly 101, an ultrasonic signal processing system 504, a pressure guide rod mechanism 103, a multi-axis translation device, and a central processing system 102; the ultrasonic stress probe includes a transmitting end and a receiving end, which respectively emit and receive ultrasonic vibration signals for measuring the residual stress inside the workpiece 503 under test; the ultrasonic signal processing system 504 is used to process the ultrasonic measurement signals, calculate and analyze stress data; the pressure guide rod mechanism is used to smoothly place the ultrasonic stress probe assembly 101 onto the workpiece surface, detect the contact situation and maintain the working pressure during testing; the multi-axis translation device is used to move the stress testing system along a preset trajectory; the central processing system 102 is used to receive and process the calculation results of the ultrasonic signal processing system 504, and synchronously control the mechanical actions of the multi-axis translation device and the pressure guide rod mechanism 103;

[0069] The ultrasonic stress probe assembly 101 includes a transmitting end assembly and a receiving end assembly. The transmitting end assembly includes an ultrasonic transmitting terminal and a transmitting end lens 502. The transmitting terminal is used to transmit ultrasonic signals 504 with high concentration and precise directionality. The transmitting end lens 502 ensures that the incident angle of the ultrasonic wave conforms to the first critical angle of refraction for a specific workpiece 503 under test. The transmitting end lens 502 has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the transmitting terminal. The transmitting end lens 502 serves as a propagation medium, allowing the ultrasonic signal 504 from the transmitting terminal to pass through it with low energy consumption and low scattering rate. The receiving end assembly includes an ultrasonic receiving terminal and a receiving end lens. The receiving terminal is used to directionally receive the ultrasonic signal 504. The receiving end lens has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the receiving terminal. The receiving end lens serves as a propagation medium, allowing the ultrasonic signal 504 to pass through it with low energy consumption and low scattering rate, and ensuring that the ultrasonic signal 504 is accurately directed towards the receiving terminal.

[0070] The ultrasonic signal processing system 504 is connected to the ultrasonic transmitting terminal and the ultrasonic receiving terminal. The ultrasonic signal processing system 504 includes an ultrasonic transducer, an ultrasonic controller, and an excitation power supply. The ultrasonic controller controls the excitation power supply to provide the ultrasonic transducer with the required electrical energy. The ultrasonic transducer generates ultrasonic waves by converting electrical energy. The ultrasonic controller can precisely control the power and frequency of the required ultrasonic waves and maintain them for a certain period of time. The ultrasonic signal processing system 504 can receive electrical signals from the ultrasonic receiving terminal and process them into electrical signals that can be recognized by a computer.

[0071] The pressure-applying guide rod mechanism 103 is mounted above the ultrasonic stress probe assembly 101, pushing the ultrasonic stress probe assembly 101 towards the surface of the workpiece 503 and applying appropriate pressure. The pressure-applying guide rod mechanism 103 includes a precision electric cylinder, a pressure-sensitive sensor, and a communication module. The precision electric cylinder uses electrical signals to control the sliding displacement of its front end and the driving force. The pressure-sensitive sensor is used to detect the contact pressure between the ultrasonic stress probe assembly 101 and the workpiece 503. The communication module is used to receive the detection data from the pressure-sensitive sensor and send it to the central processing system 102, as well as to receive control signals from the central processing system 102 for the precision electric cylinder. The connection between the pressure-applying guide rod mechanism 103 and the ultrasonic stress probe assembly 101 has a rotation fine-tuning device 109, which is used to control the fine-tuning angle by the central control system according to the reading of the pressure-sensitive sensor, so that the ultrasonic stress probe is pressed evenly onto the surface of the workpiece 503.

[0072] The multi-axis translation device includes left and right support parts 108; both left and right support parts 108 are configured with sliding or rolling movement mechanisms for linear movement by human orientation or by track guidance; the left and right support parts 108 have connecting components; the connecting components are connected by one or more casters or caster bearings, and are configured such that the right support part 108 and the left support part 104 can rotate relative to each other by a certain angle; the connecting components of the left and right support parts 108 are locked or their relative rotation angle is slowly changed with damping, so that the left and right support parts 108 can be stably fixed and relatively stationary at a preset deflection angle; the multi-axis translation device includes one or more sliding rails; the sliding rails have switchable magnetic suction seats, which can be controlled by a switch to determine whether they have magnetic adsorption properties; the sliding rails are placed on the plane of the workpiece 503 being measured, and extend... Weld seam layout; after determining the layout line, the magnetic adsorption switch of the sliding rail is turned on, so that it can be stably adsorbed onto the surface of the workpiece 503 to be tested; further, the multi-axis translation mechanism has a guide wheel 105 below it, and the guide wheel 105 contacts the surface of the workpiece 503 to support the multi-axis translation mechanism; the guide wheel 105 can cooperate with the sliding rail to make smooth low-friction movement; the guide wheel 105 has a rubber wheel skin on its periphery to increase the friction with the surface of the workpiece 503 to prevent slippage during relative movement between the guide wheel 105 and the rail; the multi-axis translation device includes a drive device 106; the drive device 106 may include a linear motor or a servo motor, or other power source device that can drive the multi-axis translation device to move; the drive device 106 is controlled by the central processing system 102 and can drive the guide wheel 105 to perform step movement.

[0073] Furthermore, the number of rails can be arranged according to the actual usage scenario; in some cases, two rails #1 and rail #2 can be arranged closely together, ensuring that the length of each rail is longer than the stress testing system of the multi-angle fillet weld in the length direction; furthermore, after the stress testing system completes the measurement work on the measurement points on rail #1, and after moving out of rail #1 and entering rail #2 as a whole, the magnetic switch of rail #1 can be turned off, so that rail #1 can be easily removed; and furthermore, arranging rail #1 closely after rail #2 allows the stress testing system to move a longer distance under the alternating guidance of rails #1 and rail #2, and saves the cost of using multiple rails;

[0074] Furthermore, the driving device 106 can be driven by a linear motor; the distance that the multi-angle fillet weld stress testing system needs to move to the next measurement point after each measurement cycle is set to m; m and the fixed ultrasonic testing distance s can be set using the following formula:

[0075] m = a 1· a 2· s,

[0076] Where a1 is the process coefficient, which can be determined according to the form of the weld, such as full weld or spot weld, which have different effects on residual stress. Theoretically, full weld causes larger residual stress but the stress distribution is more uniform, while spot weld causes the residual stress to form discrete values ​​in a regular manner, so it is necessary to allocate appropriate measurement point positions. a2 is the material processing property coefficient. Due to the different processing characteristics of various forming processes, such as hot rolling, cold rolling, cold forging, etc., the heat treatment processes are also different, resulting in different stress characteristics of the material itself. Appropriate compensation is required. Through experiments and a lot of empirical calculations, a material processing property coefficient table can be compiled to compensate for the deviation in the calculation method of residual stress caused by different processing methods, thereby changing the density of sampling measurement points.

[0077] The central processing system 102 includes a memory, a processor, and instructions stored in the memory and executable on the processor. The central processing system 102 can read and modify data recorded in the memory and execute computer programs. The central processing system 102 is connected to the ultrasonic signal processing system 504 and the multi-axis translation device, and can communicate with them. The memory includes random access memory and erasable memory. Further, the random access memory is used for temporary data caching and awaits data to be written to the erasable memory. The erasable memory can repeatedly update the data stored internally, and for the computer program, the execution logic and algorithms specified by the program can be changed through manual updates.

[0078] The multi-axis translation device mounts one or more ultrasonic stress probe assemblies 101 and one or more pressure sliding rod mechanisms onto its structure; the multi-axis translation device has braking capability and can maintain a stable static posture on a plane or inclined plane.

[0079] Example 3:

[0080] This embodiment should be understood to include at least all the features of any of the foregoing embodiments, and to further improve upon them; it provides a stress testing system based on multi-angle fillet welds, the stress testing system comprising: an ultrasonic stress probe assembly 101, an ultrasonic signal processing system 504, a pressure guide rod mechanism 103, a multi-axis translation device, and a central processing system 102; the ultrasonic stress probe includes a transmitting end and a receiving end, which respectively emit and receive ultrasonic vibration signals for measuring the residual stress inside the workpiece 503 under test; the ultrasonic signal processing system 504 is used to process the ultrasonic measurement signals, calculate and analyze stress data; the pressure guide rod mechanism is used to smoothly place the ultrasonic stress probe assembly 101 onto the workpiece surface, detect the contact situation and maintain the working pressure during testing; the multi-axis translation device is used to move the stress testing system along a preset trajectory; the central processing system 102 is used to receive and process the calculation results of the ultrasonic signal processing system 504, and synchronously control the mechanical actions of the multi-axis translation device and the pressure guide rod mechanism 103;

[0081] The ultrasonic stress probe assembly 101 includes a transmitting end assembly and a receiving end assembly. The transmitting end assembly includes an ultrasonic transmitting terminal and a transmitting end lens 502. The transmitting terminal is used to transmit ultrasonic signals 504 with high concentration and precise directionality. The transmitting end lens 502 ensures that the incident angle of the ultrasonic wave conforms to the first critical angle of refraction for a specific workpiece 503 under test. The transmitting end lens 502 has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the transmitting terminal. The transmitting end lens 502 serves as a propagation medium, allowing the ultrasonic signal 504 from the transmitting terminal to pass through it with low energy consumption and low scattering rate. The receiving end assembly includes an ultrasonic receiving terminal and a receiving end lens. The receiving terminal is used to directionally receive the ultrasonic signal 504. The receiving end lens has an incident surface and an exit surface with extremely high smoothness and is securely mounted to the receiving terminal. The receiving end lens serves as a propagation medium, allowing the ultrasonic signal 504 to pass through it with low energy consumption and low scattering rate, and ensuring that the ultrasonic signal 504 is accurately directed towards the receiving terminal.

[0082] The ultrasonic signal processing system 504 is connected to the ultrasonic transmitting terminal and the ultrasonic receiving terminal. The ultrasonic signal processing system 504 includes an ultrasonic transducer, an ultrasonic controller, and an excitation power supply. The ultrasonic controller controls the excitation power supply to provide the ultrasonic transducer with the required electrical energy. The ultrasonic transducer generates ultrasonic waves by converting electrical energy. The ultrasonic controller can precisely control the power and frequency of the required ultrasonic waves and maintain them for a certain period of time. The ultrasonic signal processing system 504 can receive electrical signals from the ultrasonic receiving terminal and process them into electrical signals that can be recognized by a computer.

[0083] The pressure-applying guide rod mechanism 103 is mounted above the ultrasonic stress probe assembly 101, pushing the ultrasonic stress probe assembly 101 towards the surface of the workpiece 503 and applying appropriate pressure. The pressure-applying guide rod mechanism 103 includes a precision electric cylinder, a pressure-sensitive sensor, and a communication module. The precision electric cylinder uses electrical signals to control the sliding displacement of its front end and the driving force. The pressure-sensitive sensor is used to detect the contact pressure between the ultrasonic stress probe assembly 101 and the workpiece 503. The communication module is used to receive the detection data from the pressure-sensitive sensor and send it to the central processing system 102, as well as to receive control signals from the central processing system 102 for the precision electric cylinder. The connection between the pressure-applying guide rod mechanism 103 and the ultrasonic stress probe assembly 101 has a rotation fine-tuning device 109, which is used to control the fine-tuning angle by the central control system according to the reading of the pressure-sensitive sensor, so that the ultrasonic stress probe is pressed evenly onto the surface of the workpiece 503.

[0084] The multi-axis translation device includes left and right support portions 108; each of the left and right support portions 108 is configured with a sliding or rolling movement mechanism for linear movement in a human-oriented or track-guided manner; each of the left and right support portions 108 has a connecting component; the connecting component is connected by one or more casters or caster bearings, and is configured such that the right support portion 108 and the left support portion 104 can rotate relative to each other by a certain angle; the connecting component of the left and right support portions 108 is locked or its relative rotation angle is slowly changed with damping, so that the left and right support portions 108 can be stably fixed at a preset deflection angle and relatively stationary; the multi-axis translation device includes a drive device 106; the drive device 106 may include a linear motor, a servo motor, or other power source device that drives the multi-axis translation device to move;

[0085] The multi-axis translation device mounts one or more ultrasonic stress probe assemblies 101 and one or more pressure sliding rod mechanisms onto its structure; the multi-axis translation device has braking capability and can maintain a stable static posture on a plane or inclined plane.

[0086] The central processing system 102 includes a memory, a processor, and instructions stored in the memory and executable on the processor. The central processing system 102 can read and modify data recorded in the memory and execute computer programs. The central processing system 102 is connected to the ultrasonic signal processing system 504 and the multi-axis translation device, and can communicate with them. The memory includes random access memory and erasable memory. The random access memory is used for temporary data caching and awaits data to be written to the erasable memory. The erasable memory can repeatedly update the data stored internally, and for the computer program, manual updates can be used to change the execution logic and algorithms specified by the program.

[0087] When the pressure-applying guide rod mechanism 103 measures the stress at a certain measurement point #k in a plane xy, in order to measure stress data along the x-axis, y-axis, or at an angle θ along the x-axis, the guide rod can be rotated so that the ultrasonic stress probe assembly 101 can measure the stress value along a specified direction; furthermore, a data set of a series of measurement points is obtained:

[0088] Stress data set S along the x-axis x =[σ x1 ,σ x2 ,……σ xn ];

[0089] Stress data set S along the y-axis y =[σ y1 ,σ y2 ,……σ yn ];

[0090] Set of stress data along an angle θ with the x-axis: S θ =[σ θ1 ,σ θ2 ,……σ θn ];

[0091] The central processing system 102 generates a series of stress cloud maps based on the above data set, such as... Figure 8 As shown, the central processing system 102 calculates the average stress and stress trend distribution, determines the coordinates of stress anomaly points, and provides magnified image information.

Claims

1. A multi-angle fillet weld based stress testing system, characterized by, The application relates to a stress testing system, which comprises an ultrasonic stress probe assembly (101), an ultrasonic signal processing system (504), a pressure guide rod mechanism (103), a multi-axis translation device and a central processing system (102). The ultrasonic stress probe assembly (101) comprises a transmitting end and a receiving end, which respectively transmit and receive ultrasonic vibration signals for measuring the internal residual stress of a workpiece (503). The ultrasonic signal processing system (504) is used for processing the ultrasonic measurement signals, calculating and analyzing the stress data. The pressure guide rod mechanism (103) is used for smoothly placing the ultrasonic stress probe assembly (101) on the surface of the workpiece, detecting the contact condition and keeping the working pressure during the test. The multi-axis translation device is used for moving the stress testing system along a preset track; the multi-axis translation device comprises one or more sliding guide rails; the sliding guide rail has a switch type magnetic adsorption seat; the sliding guide rail is placed on the plane of the workpiece and is arranged along the weld; after the arrangement route is determined, the magnetic adsorption switch of the sliding guide rail is turned on, so that the sliding guide rail can be stably adsorbed on the surface of the workpiece. The multi-axis translation device is provided with a guide wheel below and the guide wheel is in contact with the surface of the sliding guide rail to support the multi-axis translation device. The central processing system (102) is used for receiving and processing the calculation results of the ultrasonic signal processing system (504) and synchronously controlling the mechanical actions of the multi-axis translation device and the pressure guide rod mechanism (103); the multi-axis translation device comprises left and right supporting parts; the connecting parts of the left and right supporting parts are locked or slowly change the mutual rotation angle with damping, so that the left and right supporting parts can be stably fixed and relatively static at a preset deflection angle. The measured workpiece satisfies: , s is a fixed distance in the test; t0 is the time taken by the ultrasonic wave to travel s; v0 is the propagation speed of the ultrasonic wave in the specified material of the measured workpiece; when there is residual stress inside the measured workpiece, it satisfies , wherein t1 is the acoustic time of the ultrasonic wave propagating s in the measured workpiece under the influence of residual stress, and Δt is the acoustic time difference caused by the residual stress; ; wherein t tp is the acoustic time-temperature compensation value for the specified material; the residual stress inside the measured workpiece is ; K is the elastic constant of the material; Δσ represents tensile stress if positive and compressive stress if negative; The transmitting end comprises an ultrasonic transmitting end and a transmitting end lens (502); the transmitting end is used for highly concentrating and accurately directing the transmission of ultrasonic signals with specified power and frequency; the transmitting end lens (502) makes the incidence angle of the ultrasonic waves meet the first refraction critical angle for the specific workpiece (503); the transmitting end lens (502) has high smoothness of the incidence surface and the exit surface and is tightly installed with the transmitting end; the transmitting end lens (502) is used as a propagation medium to enable the ultrasonic signals of the transmitting end to pass through the lens with low energy consumption and low scattering rate; the receiving end comprises an ultrasonic receiving end and a receiving end lens; the receiving end is used for directionally receiving the ultrasonic signals; the receiving end lens has high smoothness of the incidence surface and the exit surface and is tightly installed with the receiving end; the receiving end lens is used as a propagation medium to enable the ultrasonic signals to pass through the lens with low energy consumption and low scattering rate and accurately shoot the receiving end. The pressure guide rod mechanism (103) is installed above the ultrasonic stress probe assembly (101) and pushes the ultrasonic stress probe assembly (101) to the surface of the workpiece (503) and applies appropriate pressure; the pressure guide rod mechanism (103) comprises a precision electric cylinder, a pressure sensor and a communication module. The precision electric cylinder uses electric signal to control the sliding displacement and driving force of the front end of the electric cylinder; the pressure sensor is used to detect the contact pressure between the ultrasonic stress probe assembly (101) and the measured workpiece (503); the communication module is used to receive the detection data of the pressure sensor and send it to the central processing system (102), and receive the control signal of the precision electric cylinder from the central processing system (102); The connection part of the pressure applying guide rod mechanism (103) and the ultrasonic stress probe assembly (101) has a rotating fine adjustment device (109), which is used to control the angle of fine adjustment by the central control system according to the reading of the pressure sensor, so that the ultrasonic stress probe is uniformly pressed to the surface of the measured workpiece (503); The left supporting part (104) and the right supporting part (108) have a rolling movement mechanism for linear motion in a track-guided manner; The connection part uses one or more universal wheels or universal bearings to connect, and the right supporting part (108) and the left supporting part (104) can rotate around each other by a certain angle; The multi-axis translation device installs one or more ultrasonic stress probe assemblies (101) and one or more pressure applying guide rod mechanisms on the multi-axis translation device structure; the multi-axis translation device has braking ability and can maintain a stable stationary posture on a plane or an inclined plane.

2. The multi-angle fillet weld-based stress testing system of claim 1, wherein, The ultrasonic signal processing system (504) is connected with the ultrasonic transmitting terminal and the ultrasonic receiving terminal; the ultrasonic signal processing system (504) includes an ultrasonic transducer, an ultrasonic controller and an excitation power supply; the ultrasonic controller controls the excitation power supply to make the power supply provide the required power for the ultrasonic transducer; the ultrasonic transducer converts the electric energy into ultrasonic waves; the ultrasonic controller can accurately control the power and frequency of the required ultrasonic waves and maintain a certain time; the ultrasonic signal processing system (504) can receive the electric signal from the ultrasonic receiving terminal and process it into an electric signal that can be recognized by a computer.

3. The multi-angle fillet-based stress testing system of claim 2, wherein, The multi-axis translation device includes a driving device (106), which is a linear motor or a servo motor, or other power source devices that can drive the movement of the multi-axis translation device.

4. The multi-angle fillet-based stress testing system of claim 3, wherein, The central processing system (102) includes a memory, a processor and instructions stored in the memory and executable on the processor; the central processing system (102) can read and modify the data recorded in the memory and execute computer programs; the central processing system (102) is connected with the ultrasonic signal processing system (504) and the multi-axis translation device and can communicate with each other; the memory includes random access memory and erasable memory; the random access memory is used to temporarily cache data and wait to write data to the erasable memory; the erasable memory can repeatedly update the internal stored data, and for computer programs, it can use artificial updates to change the execution logic and algorithms specified by the program.

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