Power transmission line bolt self-locking performance test device and method

Abstract

The invention discloses a power transmission line bolt self-locking performance test device and method. The device comprises a fixing frame, a rotating mechanism, a displacement sensor and a test sliding block. One end of the rotating mechanism is vertically connected with one end of the fixing frame, the other end of the rotating mechanism is connected with the displacement sensor, one end, far away from the rotating mechanism, of the displacement sensor is connected to the side face of the test sliding block, and the bottom face of the test sliding block is slidably connected with the other end of the fixing frame. A bolt test piece for testing is fixed on the test slide block in parallel relative to the ground; the rotating mechanism is used for controlling the test slide block to slide back and forth in the horizontal direction according to a certain vibration frequency and a certain amplitude; according to the device, the sliding platform for fixing the bolt is modified to be perpendicular to the ground, the test bolt is parallel to the ground, the actual connection condition and the bolt vibration condition of the power transmission line are simulated, and therefore the self-locking performance of the power transmission line bolt is detected.

Description

Technical Field

[0001] The invention belongs to the technical field of power transmission and transformation engineering, and in particular relates to a device and method for testing the self-locking performance of bolts for power transmission lines. Background Art

[0002] Transmission lines are affected by natural environmental factors for a long time. Under dynamic loads (strong wind, conductor dancing, ice shedding and jumping) or large temperature differences, bolt connections may become loose, resulting in a reduction or even disappearance of the bolt connection preload, a significant drop in the strength of the bolt connection, and some bolts may become loose or fall off, leading to structural instability of the transmission line and serious accidents such as tower collapse, which directly threatens the safety of the power grid. Therefore, reliable bolt anti-loosening measures must be taken in the design of transmission lines.

[0003] The power industry standard "Transverse Vibration Test Method for Fasteners for Transmission Towers" (DL / T1889-2018) stipulates relevant standards for the anti-loosening performance detection of fasteners for transmission towers. It is mainly based on the national standard "Transverse Vibration Test Method for Fasteners" (GB / T10431-2008), and adopts the transverse vibration test method. The test principle is: the test is carried out on a fastener transverse vibration test machine, and the fastener to be tested is tightened on the test device to generate a certain clamping force. With the help of the alternating transverse displacement generated by the test machine between the upper and lower relatively moving steel plates clamped, the connection is loosened, resulting in a reduction in the clamping force or even a complete loss of it. The instantaneous value of the clamping force is continuously recorded, and the anti-loosening performance of the fastener can be judged by comparing the changes in the recorded data. During the test, the slower the clamping force decreases, the better the anti-loosening performance.

[0004] Before the lateral vibration test, an axial preload must be applied to the fasteners. During the test, the anti-loosening performance must also be detected by the change in the axial preload. However, this method uses non-tightening connections in transmission line hardware, that is, bolt connections without axial preload. Summary of the invention

[0005] In order to overcome the above-mentioned deficiencies of the prior art, the present invention proposes a transmission line bolt self-locking performance test device, comprising: a fixing frame 1, a rotating mechanism, a displacement sensor 5 and a test slide 7;

[0006] One end of the rotating mechanism is vertically connected to one end of the fixing frame 1, and the other end of the rotating mechanism is connected to the displacement sensor 5. The end of the displacement sensor 5 away from the rotating mechanism is connected to the side of the test slider 7. The bottom surface of the test slider 7 is slidably connected to the other end of the fixing frame 1. The bolt specimen 11 used for the test is fixed on the test slider 7 parallel to the ground.

[0007] The rotating mechanism is used to control the test slide block 7 to slide back and forth in the horizontal direction at a certain vibration frequency and a certain amplitude.

[0008] Preferably, the fixing frame 1 comprises: a base and a support seat and a sliding support platform vertically arranged at both ends of the base, the rotating mechanism is vertically connected to the end of the support seat away from the base, and the bottom surface of the test slider 7 is slidably connected to the top surface of the sliding support platform away from the base in the horizontal direction.

[0009] Preferably, a rolling bearing 6 is provided between the bottom surface of the test slider 7 and the top surface of the sliding support platform away from the base.

[0010] Preferably, the rotating mechanism comprises: an eccentric wheel 2, a rotating arm 3 and a rotating shaft 4;

[0011] The eccentric wheel 2 is hinged at one end of the support seat away from the base, the side of the eccentric wheel 2 away from the hinge is connected to the rotating arm 3, the end of the rotating arm 3 away from the eccentric wheel 2 is connected to the rotating shaft 4, and the rotating shaft 4 is installed on the displacement sensor 5.

[0012] Preferably, one or more test holes are provided on the test slide block 7, and the bolt test piece 11 is arranged in the test hole, and the bolt test piece 11 is non-tightly connected to the test hole.

[0013] Preferably, the test hole is a long hole extending in a horizontal direction to the ground.

[0014] Preferably, the test holes include one or more of the following: M16 nut test hole 8, M20 nut test hole 9, and M24 nut test hole 10.

[0015] Based on the same inventive concept, the present invention also provides a method for testing the self-locking performance of transmission line bolts.

[0016] According to the vibration frequency and amplitude parameters required for the self-locking performance test of the transmission line bolts and the displacement parameters on the displacement sensor, the rotation frequency of the test slider 7 under the natural frequency vibration in the horizontal direction is calculated;

[0017] Based on the rotation frequency, controlling the rotation mechanism to perform a vibration test on the bolt specimen 11 and obtaining the displacement data of the bolt specimen 11;

[0018] Determine the self-locking performance of the power transmission line bolts based on the deflection data of the bolt specimen 11 after the vibration test;

[0019] Wherein, the transmission line bolt self-locking performance test device is the transmission line bolt self-locking performance test device as described in any one of claims 1 to 7.

[0020] Preferably, the step of obtaining the offset data of the bolt specimen 11 includes:

[0021] On the outer plane of the nut 13, mark three measuring points A, B, and C at intervals of 120 degrees;

[0022] Measure the distances between the three measuring points A, B, and C and the end of the bolt 12 before and after the test.

[0023] The relative rotation angle between the nut 13 and the bolt 12 is calculated based on the measured distance.

[0024] Preferably, the calculation formula of the relative rotation angle between the nut 13 and the bolt 12 is as follows:

[0025]

[0026]

[0027]

[0028] β=(β A +β B +β C ) / 3

[0029] Among them, L A1 is the initial measured value of the distance between point A and the end of the screw, L B1 is the initial measured value of the distance between point B and the end of the screw, L C1 is the initial measured value of the distance between point C and the end of the screw, L A2 is the final measured value of the distance between point A and the end of the screw, L B2 is the final measured value of the distance between point B and the end of the screw, L C2 is the final measured value of the distance between point C and the end of the screw, β is the relative rotation angle between the nut and the screw, A is the relative rotation angle between nuts at point A, β B is the relative rotation angle between nuts at point B, β C is the relative rotation angle between nuts at point C.

[0030] Preferably, the determining of the self-locking performance of the transmission line bolts includes:

[0031] The strength of the self-locking performance of the power transmission line bolt is determined based on the rotation angle of the nut 13 after the vibration test.

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

[0033] A transmission line bolt self-locking performance test device and method, comprising: a fixed frame 1, a rotating mechanism, a displacement sensor 5 and a test slide 7; one end of the rotating mechanism is vertically connected to one end of the fixed frame 1, the other end of the rotating mechanism is connected to the displacement sensor 5, the end of the displacement sensor 5 away from the rotating mechanism is connected to the side of the test slide 7, the bottom surface of the test slide 7 is slidably connected to the other end of the fixed frame 1, and the bolt test piece 11 used in the test is fixed on the test slide 7 parallel to the ground; the rotating mechanism is used to: control the test slide 7 to slide back and forth in the horizontal direction at a certain vibration frequency and a certain amplitude, and the device simulates the actual connection condition of the transmission line and the vibration condition of the bolt to realize the detection and evaluation of the self-locking performance of the bolt, improves the material procurement, detection and acceptance method of transmission line fasteners, provides a basis for the revision of the transmission line anti-loosening test standard, and promotes the research, production and engineering application of transmission line bolt anti-loosening products. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of a transmission line bolt self-locking performance test device provided by the present invention;

[0035] Figure 2 A schematic diagram of a slider of a transmission line bolt self-locking performance test device provided by the present invention;

[0036] Figure 3 A flow chart of a method for testing the self-locking performance of bolts for power transmission lines provided by the present invention;

[0037] Figure 4 A schematic diagram of the rotation angle measurement principle of a transmission line bolt self-locking performance test device provided by the present invention;

[0038] Among them, 1-fixed frame, 2-eccentric wheel, 3-rotating arm, 4-rotating shaft, 5-displacement sensor, 6-rolling bearing, 7-test slider, 8-M16 nut test hole, 9-M20 nut test hole, 10-M24 nut test hole, 11-bolt specimen, 12-bolt; 13-nut. DETAILED DESCRIPTION

[0039] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings.

[0040] Embodiment 1:

[0041] The present invention provides a transmission line bolt self-locking performance test device, such as Figure 1 As shown, it includes: a fixed frame 1, a rotating mechanism, a displacement sensor 5 and a test slider 7;

[0042] One end of the rotating mechanism is vertically connected to one end of the fixing frame 1, and the other end of the rotating mechanism is connected to the displacement sensor 5. The end of the displacement sensor 5 away from the rotating mechanism is connected to the side of the test slider 7. The bottom surface of the test slider 7 is slidably connected to the other end of the fixing frame 1. The bolt specimen 11 used for the test is fixed on the test slider 7 parallel to the ground.

[0043] The rotating mechanism is used to control the test slide block 7 to slide back and forth in the horizontal direction at a certain vibration frequency and a certain amplitude.

[0044] This device arranges the fixed test slider 7 in a vertical direction so that the bolt specimen 11 can be parallel to the ground during the test, thereby simulating the actual connection condition of the circuit. Compared with the test device in the prior art, this device can be closer to the actual situation and improve the test accuracy. The test slider 7 is provided with mounting holes corresponding to different bolt specifications, and the bolt specimen 11 can be installed on the test slider 7. The bolt specimen 11 and the test slider 7 are installed with a non-tightening connection.

[0045] Preferably, the fixing frame 1 comprises: a base and a support seat and a sliding support platform vertically arranged at both ends of the base, the rotating mechanism is vertically connected to the end of the support seat away from the base, and the bottom surface of the test slider 7 is slidably connected to the top surface of the sliding support platform away from the base in the horizontal direction.

[0046] The sliding support platform and the support seat respectively support the test slider 7 and the rotating mechanism to reduce the extra force exerted by the device in the vertical direction to affect the test results.

[0047] Preferably, a rolling bearing 6 is provided between the bottom surface of the test slider 7 and the top surface of the sliding support platform away from the base.

[0048] The rolling bearing 6 facilitates the sliding of the slider in the horizontal direction, and can also reduce the friction of the test slider 7 and the additional influence of other data on the measurement data during the test simulation, thereby further improving the accuracy of the test data.

[0049] Preferably, the rotating mechanism comprises: an eccentric wheel 2, a rotating arm 3 and a rotating shaft 4;

[0050] The eccentric wheel 2 is hinged at one end of the support seat away from the base, the side of the eccentric wheel 2 away from the hinge is connected to the rotating arm 3, the end of the rotating arm 3 away from the eccentric wheel 2 is connected to the rotating shaft 4, and the rotating shaft 4 is installed on the displacement sensor 5.

[0051] Driven by the eccentric wheel 2, the test slide block 7 can slide back and forth horizontally at a certain vibration frequency and a certain amplitude.

[0052] like Figure 2 As shown, the test slide block 7 is provided with one or more test holes, the bolt test piece 11 is arranged in the test hole, and the bolt test piece 11 is non-tightly connected to the test hole.

[0053] Preferably, the test hole is a long hole extending in a horizontal direction to the ground.

[0054] When the test slide block 7 slides horizontally back and forth, the non-tightly connected test bolts 11 can vibrate freely, simulating the vibration of the bolts when the transmission line is actually connected.

[0055] Preferably, the test holes include one or more of the following: M16 nut test hole 8, M20 nut test hole 9, and M24 nut test hole 10.

[0056] It can be applied to various non-fastener systems (self-locking bolts or cotter pins with additional anti-loosening mechanisms) to identify the anti-loosening performance of fasteners and compare the anti-loosening effects of various fasteners.

[0057] Embodiment 2:

[0058] Based on the same inventive concept, the present invention also provides a method for testing the self-locking performance of transmission line bolts, the flow chart of which is as follows: Figure 3 As shown;

[0059] According to the vibration frequency and amplitude parameters required for the self-locking performance test of the transmission line bolts and the displacement parameters on the displacement sensor, the rotation frequency of the test slider 7 under the natural frequency vibration in the horizontal direction is calculated;

[0060] Based on the rotation frequency, controlling the rotation mechanism to perform a vibration test on the bolt specimen 11 and obtaining the displacement data of the bolt specimen 11;

[0061] Determine the self-locking performance of the power transmission line bolts based on the deflection data of the bolt specimen 11 after the vibration test;

[0062] Wherein, the transmission line bolt self-locking performance test device is the transmission line bolt self-locking performance test device as described in any one of claims 1 to 7.

[0063] like Figure 4 As shown, the obtaining of the offset data of the bolt specimen 11 includes:

[0064] On the outer plane of the nut 13, mark three measuring points A, B, and C at intervals of 120 degrees;

[0065] Measure the distances between the three measuring points A, B, and C and the end of the bolt 12 before and after the test.

[0066] The relative rotation angle between the nut 13 and the bolt 12 is calculated based on the measured distance.

[0067] For non-threaded connections such as cotter pins, under certain vibration test conditions, after the required number of vibrations, the cotter pin’s anti-loosening performance can be judged by directly observing whether the cotter pin falls off, deforms, breaks, etc.

[0068] For non-tightening bolts connected by self-locking bolts, it is necessary to evaluate the self-locking performance of the bolt 12 by judging the rotation angle of the nut 13 after the required number of vibrations according to certain vibration test conditions. The smaller the rotation angle of the nut 13 relative to the screw, the better the self-locking performance of the bolt.

[0069] During bolt connection, the nut 13 and the end of the screw rod are not in the same plane.

[0070] The method for measuring the rotation angle of the nut 13 includes:

[0071] 1) On the outer plane of the nut, mark three measuring points A, B, and C at intervals of 120 degrees. The three measuring points should be on the same circle as the center of the nut.

[0072] 2) After the bolt specimen is installed on the vibration machine, use a vernier caliper to measure the distance between A, B, and C and the end of the screw; the distance measurement should be the same as the distance between the screw axis and the three distances L. A1 , L B1 , L C1 .

[0073] 3) According to certain vibration test conditions, after the required number of vibrations, when the test machine stops completely, use a vernier caliper to measure the distance between A, B, and C and the end of the screw; the distance measurement should be the same as that of the screw axis, and the three distances are L A2 , L B2 , L C2 .

[0074] Preferably, the calculation formula of the relative rotation angle between the nut 13 and the bolt 12 is as follows:

[0075]

[0076]

[0077]

[0078] β=(β A +β B +β C ) / 3

[0079] Among them, L A1 is the initial measured value of the distance between point A and the end of the screw, L B1 is the initial measured value of the distance between point B and the end of the screw, LC1 is the initial measured value of the distance between point C and the end of the screw, L A2 is the final measured value of the distance between point A and the end of the screw, L B2 is the final measured value of the distance between point B and the end of the screw, L C2 is the final measured value of the distance between point C and the end of the screw, β is the relative rotation angle between the nut and the screw, A is the relative rotation angle between nuts at point A, β B is the relative rotation angle between nuts at point B, β C is the relative rotation angle between nuts at point C.

[0080] Preferably, the determining of the self-locking performance of the transmission line bolts includes:

[0081] The strength of the self-locking performance of the power transmission line bolt is determined based on the rotation angle of the nut 13 after the vibration test.

[0082] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0083] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0084] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0085] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the protection scope of the claims to be approved.

Claims

1. A transmission line bolt self-locking performance test device, characterized in that: include: A fixed frame (1), a rotating mechanism, a displacement sensor (5) and a test slide block (7); One end of the rotating mechanism is vertically connected to one end of the fixing frame (1), the other end of the rotating mechanism is connected to the displacement sensor (5), the end of the displacement sensor (5) away from the rotating mechanism is connected to the side of the test slider (7), the bottom surface of the test slider (7) is slidably connected to the other end of the fixing frame (1), and the bolt specimen (11) used for the test is fixed on the test slider (7) parallel to the ground; The rotating mechanism is used to control the test slide block (7) to slide back and forth in the horizontal direction at a certain vibration frequency and a certain amplitude.

2. The device according to claim 1, characterized in that The fixing frame (1) comprises: a base and a support seat and a sliding support platform vertically arranged at both ends of the base, the rotating mechanism is vertically connected to the end of the support seat away from the base, and the bottom surface of the test slider (7) is slidably connected to the top surface of the sliding support platform away from the base in the horizontal direction.

3. The device according to claim 2, characterized in that A rolling bearing (6) is provided between the bottom surface of the test sliding block (7) and the top surface of the sliding support platform away from the base.

4. The device according to claim 2, characterized in that The rotating mechanism comprises: an eccentric wheel (2), a rotating arm (3) and a rotating shaft (4); The eccentric wheel (2) is hinged at one end of the support seat away from the base, the side of the eccentric wheel (2) away from the hinge is connected to a rotating arm (3), the end of the rotating arm (3) away from the eccentric wheel (2) is connected to a rotating shaft (4), and the rotating shaft (4) is mounted on the displacement sensor (5).

5. The device according to claim 1, characterized in that One or more test holes are provided on the test slide block (7), the bolt test piece (11) is arranged in the test hole, and the bolt test piece (11) is non-tightly connected to the test hole.

6. The device according to claim 5, characterized in that The test hole is a long hole extending in a horizontal direction with the ground.

7. The device according to claim 5, characterized in that The test holes include one or more of the following: an M16 nut test hole (8), an M20 nut test hole (9), and an M24 nut test hole (10).

8. A method for testing the self-locking performance of transmission line bolts, characterized in that: Calculate the rotation frequency of the test slider (7) under the horizontal natural frequency vibration according to the vibration frequency and amplitude parameters required for the self-locking performance test of the transmission line bolts and the displacement parameters on the displacement sensor; Based on the rotation frequency, controlling the rotation mechanism to perform a vibration test on the bolt test piece (11) and obtaining displacement data of the bolt test piece (11); Determining the self-locking performance of the power transmission line bolts according to the deflection data of the bolt specimen (11) after the vibration test; Wherein, the transmission line bolt self-locking performance test device is the transmission line bolt self-locking performance test device as described in any one of claims 1 to 7.

9. The method according to claim 8, characterized in that The step of obtaining the offset data of the bolt test piece (11) comprises: On the outer surface of the nut (13), mark three measuring points A, B, and C at intervals of 120 degrees; Measure the distances between the three measuring points A, B and C and the end of the bolt (12) before and after the test respectively; The relative rotation angle between the nut (13) and the bolt (12) is calculated based on the measured distance.

10. The method according to claim 9, characterized in that The calculation formula of the relative rotation angle between the nut (13) and the bolt (12) is as follows: β＝(β A +β B +β C ) / 3 Among them, L A1 is the initial measured value of the distance between point A and the end of the screw, L B1 is the initial measured value of the distance between point B and the end of the screw, L C1 is the initial measured value of the distance between point C and the end of the screw, L A2 is the final measured value of the distance between point A and the end of the screw, L B2 is the final measured value of the distance between point B and the end of the screw, L C2 is the final measured value of the distance between point C and the end of the screw, β is the relative rotation angle between the nut and the screw, A is the relative rotation angle between nuts at point A, β B is the relative rotation angle between nuts at point B, β C is the relative rotation angle between nuts at point C.

11. The method according to claim 9, characterized in that The method of judging the self-locking performance of the transmission line bolts includes: The strength of the self-locking performance of the power transmission line bolt is judged according to the rotation angle of the nut (13) after the vibration test.

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