A test device and system for measuring longitudinal resistance of rail

Abstract

The present invention relates to a test device and system for measuring the longitudinal resistance of a rail, the device comprising: a base; a ratchet guide fixed on the base; a box body spanning the ratchet guide; a pawl assembly passing through the box body, comprising an active rotary rod and a left active pawl and a right active pawl respectively arranged on both sides of the active rotary rod along the extension direction of the ratchet guide, one of the left active pawl and the right active pawl can slide in its corresponding direction when lifted, and the other falls on the ratchet guide to form a locked state sliding in its corresponding direction; a horizontal plate arranged on the top of the box body, on which the sleeper and the rail to be tested are fixed in turn; a displacement sensor arranged on one side of the box body through a bracket, and connected to the opposite end of the stretched end of the rail to be tested. Compared with the prior art, the present invention is used to cooperate with a longitudinal tensile testing machine, which can not only protect the longitudinal pulling machine, but also has a self-protection mechanism, and has the advantages of simple structure, easy use, and low cost.

Description

Technical Field

[0001] The invention relates to the technical field of railway testing equipment, and in particular to a testing device and a system for measuring the longitudinal resistance of a rail. Background Art

[0002] The test for measuring the longitudinal resistance of rails adopts the Chinese railway industry standard. The principle is: assemble the short rails on the rail-bearing surface of the fixed sleeper with fasteners, apply longitudinal tension to the rails, record the load and the longitudinal displacement of the rails relative to the sleepers, unload when the rails slip, and obtain the longitudinal resistance of the rails from the load-displacement curve.

[0003] Longitudinal tensile testing machine (hereinafter referred to as longitudinal tensile machine) is a widely used equipment among many testing instruments, mainly used for tensile mechanical properties testing of metal and non-metal materials.

[0004] When we do the test of measuring the longitudinal resistance of rails, the purpose is to let the longitudinal tensile testing machine pull the rails to the left until the rails slip and stop the test, so as to measure the tension required for the rails to slip. However, due to uncertain factors (such as software instability), sometimes the machine will push the rails to the right instead. Since the longitudinal tensile test is mainly used to measure the tensile mechanical properties of materials, its main function is to pull rather than press, and the testing machine and rails are fixed (the previous test was to directly fix the sleepers and rails on the test bench). When the machine pushes the rails to the right, it will also be subject to a reaction force to the left. When this force reaches a certain level, it is likely to damage the machine. Therefore, the longitudinal tensile testing machine needs to be protected when doing the test of measuring the longitudinal resistance of rails. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a test device and system for measuring the longitudinal resistance of rails.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A test device for measuring the longitudinal resistance of a rail, comprising a base arranged on a test bench, and further comprising:

[0008] A ratchet guide rail fixed on the base;

[0009] A box body, straddling the ratchet guide rail;

[0010] A pawl assembly passes through the box body, and includes an active rotary rod and a left active pawl and a right active pawl respectively arranged on both sides of the active rotary rod along the extending direction of the ratchet guide rail, wherein one of the left active pawl and the right active pawl can slide in its corresponding direction when lifted, and the other falls on the ratchet guide rail to form a locked state of sliding in its corresponding direction;

[0011] A horizontal plate, arranged on the top of the box, on which the sleepers and the rails to be tested are fixed in sequence;

[0012] The displacement sensor is arranged on one side of the box body through a bracket and connected to the opposite end of the stretched end of the steel rail to be tested.

[0013] Preferably, the ratchet guide rails are provided with two parallel arranged ones.

[0014] Preferably, a pressure sensor is provided at the bottom of the ratchet guide rail.

[0015] Preferably, the box body comprises an outer box and an inner box which is sleeved in the outer box and connected to the outer box, and the ratchet guide rail is arranged between the inner side of the outer box and the outer side of the inner box.

[0016] Preferably, one end of the active rotary rod extends out of one side of the box body and is provided with a power assist rod.

[0017] Preferably, a leveler is provided on the horizontal plate.

[0018] Preferably, four levelers are provided and distributed around the horizontal plate.

[0019] Preferably, the top inner side of the box body is provided with fixing patches at positions corresponding to the left active pawl and the right active pawl, respectively, and strong magnets are provided on the upper side of the left active pawl, the upper side of the right active pawl and the lower side of the fixing patches.

[0020] Preferably, a T-shaped slot is provided on the base, and the ratchet guide rail is fixed in the T-shaped slot.

[0021] A test system using the above-mentioned test device for measuring the longitudinal resistance of a rail also includes a longitudinal tensile testing machine and a data analysis device. The longitudinal tensile testing machine is provided with a dynamometer, and the longitudinal tensile testing machine is connected to the stretched end of the rail to be tested. The data analysis device is respectively connected to the control end of the longitudinal tensile testing machine, the output end of the dynamometer, the output end of the pressure sensor, and the output end of the displacement sensor.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1. This test device is used in conjunction with the longitudinal tensile testing machine. It can not only protect the longitudinal tensile machine, but also has a self-protection mechanism. This device uses high-strength bolts to fix two ratchet guides to the test bench, and controls the sliding direction by rotating the active rotary rod. For example, if the active rotary rod is rotated counterclockwise, the sleeper and the rail are locked to the left and slidable to the right. When the machine pushes the rail to the right, it will not be subject to the reaction force to the left, thereby protecting the machine and greatly reducing the risk of machine damage. It is simple to install and low cost.

[0024] 2. A horizontal plate is provided on the upper part of the outer box, and there is a leveler on each of the four sides of the horizontal plate. The leveler is adjusted by rotating the bolts arranged around the horizontal plate so that the bubble is located in the middle of the leveler, thereby ensuring that the horizontal plate is in a horizontal state, improving the test accuracy, and greatly reducing the experimental error caused by the inclination of the tension rail.

[0025] 3. At the same time, the device has a self-protection mechanism. This set of devices can measure the pull-slip performance of different types of rails and the tensile properties of other materials. Due to factors such as the uncertainty of the tensile strength of the material, when the force borne by the device components is greater than the ultimate bearing capacity, it will cause relative displacement between the device and the test bench or even damage to the parts. Therefore, a pressure sensor is buried in the lower part of the ratchet guide rail. The pressure sensor is connected to the computer software. When the pressure reaches a certain value, the longitudinal tensile test machine will be stopped through the data analysis device to protect the test device. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 This is a diagram of the split structure of the present invention from a top view;

[0028] Figure 3 This is a split structure diagram of the present invention from an upward viewing angle;

[0029] Figure 4 It is a schematic diagram of the working process of the present invention;

[0030] Figure 5 Graph showing the load-displacement curve obtained by the present invention in the embodiment.

[0031] Markings in the figure: 1. Fixed angle code, 2. Horizontal plate, 3. Leveler, 4. Latch, 5. Active rotary rod, 6. Power assist rod, 7. Displacement sensor, 8. Displacement sensor output line, 9. Bracket, 10. Fastening bolts, 11. T-bar, 12. Pressure sensor, 13. Fixing bolts, 14. Outer box, 15. Inner box, 16. Fixed patch, 17. Left active pawl, 18. Right active pawl, 19. Ratchet guide, 20. Strong magnet, 21. Base, 22. T-slot, 23. Cylinder, 24. Longitudinal tensile testing machine, 25. Rail, 26. Fastener, 27. Sleeper, 28. Test bench, 29. Tension meter, 30. Data analysis device, 31. Transmission line. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0033] Example

[0034] like Figures 1 to 3 As shown, the present application proposes a test device for measuring the longitudinal resistance of a rail, which is used to cooperate with a longitudinal tensile testing machine 24, comprising: a base 21 arranged on a test bench 28, the base 21 being provided with a T-slot 22; a ratchet guide rail 19 fixed in the T-slot 22 of the base 21; a box body, spanning the ratchet guide rail 19; a pawl assembly, passing through the box body, comprising an active rotary rod 5 and a left active pawl 17 and a right active pawl 18 respectively arranged on both sides of the active rotary rod 5 along the extending direction of the ratchet guide rail 19, and the left active pawl 17 and the right active pawl 18 are respectively arranged on both sides of the active rotary rod 5 along the extending direction of the ratchet guide rail 19. The claws 18 are both located above the ratchet guide 19, one of which can slide in its corresponding direction when lifted, and the other falls on the ratchet guide 19 to form a locked state of sliding in its corresponding direction; the horizontal plate 2 is arranged on the top of the box, on which the sleeper 27 and the rail 25 to be tested are fixed in sequence; the displacement sensor 7 is arranged on one side of the box through the bracket 9, and is connected to the opposite end of the stretched end of the rail 25 to be tested, and the bottom of the bracket 9 can be inserted into the T-slot 22 of the base 21, and the position of the bracket 9 is adjusted by the fastening bolts 10 on the base 21.

[0035] The box body includes an outer box 14 and an inner box 15 which is inserted into and connected to the outer box 14. In this embodiment, the inner box 15 and the outer box 14 are connected by a latch 4 to form a whole, wherein the connection between the latch 4 and the inner box 15 and the outer box 14 is rigidly connected.

[0036] In this embodiment, two parallel ratchet rails 19 are provided, and the ratchet rails 19 are located between the inner side of the outer box 14 and the outer side of the inner box 15. Two left active pawls 17 and two right active pawls 18 are provided respectively. A pressure sensor 12 is provided at the bottom of the ratchet rails 19.

[0037] The horizontal plate 2 is rectangular, and a leveler 3 is provided on each of the four sides of the horizontal plate 2. The leveler 3 is adjusted by adjusting the bolts provided around the horizontal plate 2 so that the bubbles are located in the middle of the leveler 3, thereby ensuring that the horizontal plate 2 is in a horizontal state.

[0038] The top of the inner side of the box, in this embodiment, is the top of the inner side of the outer box 14, and fixed patches 16 are respectively provided at the positions corresponding to the left active pawl 17 and the right active pawl 18. The upper side of the left active pawl 17, the upper side of the right active pawl 18 and the lower side of the fixed patch 16 are all provided with strong magnets 20. When the active rotary rod 5 rotates counterclockwise, due to the action of the strong magnet 20, the magnetic attraction between the right active pawl 18 and the right fixed patch 16 is always greater than the magnetic attraction between the left active pawl 17 and the left fixed patch 16, and the right active pawl is separated from the right fixed patch, so that the left active pawl 17 can always be kept in contact with the ratchet guide rail 19, so that it is in a locked state to the left and in a slidable state to the right. When the active rotary rod 5 rotates clockwise, the situation is the opposite.

[0039] One end of the active rotating rod 5 extends out of one side of the box body and is provided with a booster rod 6, which can effectively increase the acting force between the hand and the active rotating rod 5.

[0040] The top of the horizontal plate 2 is provided with a fixing angle code 1 for fixing the sleeper 27 , and is also provided with a plurality of bolt holes for adjusting the position of the fixing angle code 1 .

[0041] The present application proposes a test system using the above-mentioned test device, which also includes a longitudinal tensile testing machine 24 and a data analysis device 30. In the present embodiment, the data analysis device 30 is a computer. A dynamometer 29 is provided on the cylinder 23 of the longitudinal tensile testing machine 24, and the longitudinal tensile testing machine 24 is connected to the stretched end of the rail 25 to be tested through the cylinder 23. The data analysis device 30 is respectively connected to the control end of the longitudinal tensile testing machine 24, the output end of the dynamometer 29, the output end of the pressure sensor 12, and the output end of the displacement sensor 7 through a data acquisition device. Both the pressure sensor 12 and the displacement sensor 7 are powered by an external power supply module. The pressure sensor 12 transmits data to the data analysis device 30. When the pressure reaches the set threshold, the data analysis device 30 sends a signal to stop the longitudinal tensile testing machine 24 from working to protect the test device.

[0042] The installation process of this test system includes: firstly placing the base 21 on the test bench 28, aligning the T-slot 22 of the base 21 with the T-slot of the test bench 28, then installing the upper structure and the sensor on the base 21, passing the output line through the outlet hole of the base, inserting the T-bar 11 into the T-slot 22 of the base 21 and fixing it with the fixing bolt 13; fixing the sleeper 27 on the horizontal plate 2 with the fixing angle code 1, fixing the rail 25 on the sleeper 27 with the fastener 26, adjusting the bolts around the horizontal plate 2 so that the bubbles of the four levelers 3 are in the middle; installing the longitudinal tensile tester 24 on the test bench, connecting one end of the rail 25 with the cylinder 23 of the longitudinal tensile tester 24, in this embodiment, installing the longitudinal tensile tester 24 on the left side of this test device, and rotating the active rotary rod 5 counterclockwise; installing the displacement sensor 7 on the bracket 9 and placing it on the right side of this test device, adjusting the position so that the ejector pin of the displacement sensor 7 is in close contact with the rail 25, and tightening the fixing bolt 10 to fix the bracket 9.

[0043] like Figure 4 As shown in the figure, the test process of the test system includes:

[0044] The first step is to set the experimental parameters (loading rate, sampling frequency, etc.) in the data analysis device 30;

[0045] The second step is to load the collected data, including the tension on the rail 25, the displacement generated, and the pressure on the pressure sensor 12 located inside the base 21;

[0046] The third step is to establish a database for the collected experimental data;

[0047] The fourth step is to select the corresponding experimental data in the database according to the experimental requirements, use the existing software to analyze the data, automatically draw the graph, and output the experimental results.

[0048] In this embodiment, the test loading requirements are: apply tension to one end of the rail 25 at a constant loading rate of 9kN / min to 11kN / min, and automatically measure the load and relative longitudinal displacement of the rail 25 from the beginning of the loading cycle. When the rail 25 slips or the load exceeds 4 times the performance requirements of the fastener 26, the load should be quickly unloaded to zero and the displacement of the rail 25 should be continuously measured for 2 minutes. The fastener 26 should not be disassembled or adjusted in any way during the test. Repeat the above loading / unloading process 3 times, stay for 3 minutes after each unloading and then continue loading. Draw the following figure: Figure 5 The load-displacement curve for each loading / unloading cycle is shown.

[0049] Figure 5 The horizontal axis is displacement and the vertical axis is longitudinal force. Determine the displacements D1 and D2 from the figure, and then calculate D3 according to the following formula: D3=D1-D2.

[0050] In each curve, the F value is determined by the force required to cause the initial elastic displacement D3. If the loading cycle is stopped when the load is greater than or equal to 4 times the performance requirement of the fastener 26, the F value is the maximum value of the test. The F value of the first loading cycle is discarded, and the average value obtained based on the F values ​​of the next three loading cycles is used as the longitudinal resistance value of the rail 25.

Claims

1. A test device for measuring the longitudinal resistance of a rail, comprising a base arranged on a test bench, characterized in that: Also includes: A ratchet guide rail fixed on the base; A box body, straddling the ratchet guide rail; A pawl assembly passes through the box body, and includes an active rotary rod and a left active pawl and a right active pawl respectively arranged on both sides of the active rotary rod along the extending direction of the ratchet guide rail, wherein one of the left active pawl and the right active pawl can slide in its corresponding direction when lifted, and the other falls on the ratchet guide rail to form a locked state of sliding in its corresponding direction; A horizontal plate, arranged on the top of the box, on which the sleepers and the rails to be tested are fixed in sequence; A displacement sensor is arranged on one side of the box body through a bracket and connected to an end opposite to the stretched end of the steel rail to be tested; The ratchet guide rails are provided with two parallel arranged ones; A pressure sensor is provided at the bottom of the ratchet guide rail.

2. A test device for measuring the longitudinal resistance of a rail according to claim 1, characterized in that: The box body comprises an outer box and an inner box which is sleeved in the outer box and connected to the outer box, and the ratchet guide rail is arranged between the inner side of the outer box and the outer side of the inner box.

3. A test device for measuring the longitudinal resistance of a rail according to claim 1, characterized in that: One end of the active rotating rod extends out of one side of the box body and is provided with a booster rod.

4. A test device for measuring the longitudinal resistance of a rail according to claim 1, characterized in that: A leveler is arranged on the horizontal plate.

5. A test device for measuring the longitudinal resistance of a rail according to claim 4, characterized in that: The levelers are provided in four numbers and are distributed around the horizontal plate.

6. A test device for measuring the longitudinal resistance of a rail according to claim 1, characterized in that: The top of the inner side of the box body is provided with fixing patches at positions corresponding to the left active pawl and the right active pawl, respectively. Strong magnets are provided on the upper side of the left active pawl, the upper side of the right active pawl and the lower side of the fixing patches.

7. A test device for measuring the longitudinal resistance of a rail according to claim 1, characterized in that: The base is provided with a T-shaped slot, and the ratchet guide rail is fixed in the T-shaped slot.

8. A test system using the test device for measuring the longitudinal resistance of a rail according to any one of claims 1 to 7, characterized in that: It also includes a longitudinal tensile testing machine and a data analysis device. The longitudinal tensile testing machine is provided with a tensile gauge, and the longitudinal tensile testing machine is connected to the stretched end of the rail to be tested. The data analysis device is respectively connected to the control end of the longitudinal tensile testing machine, the output end of the tensile gauge, the output end of the pressure sensor, and the output end of the displacement sensor.

Images