Torsion test method meeting EN14363 standard

Abstract

The invention relates to the field of rail transit measurement, in particular to a torsion test method meeting the EN14363 standard. Comprising the steps of preparing four force measuring wheel pairs, and performing two-moving and two-dragging; the bogie is cushioned, so that the bogie and the vehicle body are twisted; a wheel set lifting amount testing device is installed on the bogie, and an attack angle testing device is installed on the twisted line; checking the track and wheel states, and confirming the most unfavorable load position; carrying out gas test and gas-free test on the twisted line, and evaluating the test result on site; and checking the line state. On the basis of detailed interpretation of the EN14363 standard, the detailed torsion test method meeting the EN14363 standard is provided, so that the torsion test of the railway vehicle under the EN14363 standard is convenient to implement, and the trafficability is high.

Description

Technical Field

[0001] The invention relates to the field of rail transit measurement, and in particular to a torsion test method meeting EN14363 standards. Background Art

[0002] In the field of rail transit, the derailment safety of vehicles has always been a focus of attention. Method 1: Add pads to the primary and secondary springs of the vehicle to cause the bogie and the car body to twist. The vehicle passes through the R150m twisted line to test the wheel lift and wheel-rail force indicators of the vehicle on the twisted line. Method 2: The minimum vertical force is obtained by the wheel lift test. The vehicle passes the R150m curve without twisting and superelevation to obtain the maximum lateral force. The maximum lateral force / minimum vertical force = maximum derailment coefficient. Method 3: The wheel lift test obtains the wheel weight reduction rate. The vehicle passes the minimum radius curve to obtain the bogie slewing damping coefficient X. The X coefficient and wheel weight reduction rate are evaluation indicators. Method 1 requires the preparation of a force measuring wheelset, the need to test the wheel lift amount, and a special twisting line is required. Method 2 includes two tests. The first is a wheel lift test on a weighing platform, and the second is that the vehicle needs to perform a sawing test on a force measuring rail section with a superelevation of 0mm and a curve radius of R150m. Method 3 requires repeated verification of tests and simulation models, which is somewhat difficult. In summary, it is very convenient for manufacturers with twisted circuits that meet the EN14363 standard to carry out the twist test of method 1. Summary of the invention

[0004] Based on a detailed interpretation of the EN14363 standard, the present invention proposes a detailed torsion test method that meets the EN14363 standard, so that the torsion test of rail vehicles under the EN14363 standard is easy to implement and has a high passability.

[0005] The torsion test method provided by the present invention that meets the EN14363 standard includes the following steps:

[0006] (1) Prepare four dynamometric wheelsets, two for driving and two for trailing, to replace the original wheelsets for the trailer and the driving car;

[0007] The test uses a continuous dynamometric wheelset to obtain the wheel-rail lateral force and wheel-rail vertical force, calculate the derailment coefficient, wheel weight reduction rate, etc., and conduct a derailment safety assessment.

[0008] (2) Adding pads to the bogies causes distortion of the bogies and car bodies;

[0009] Calculate the distortion of the car body and bogie with reference to EN14363, calculate the pad thickness required to achieve the distortion of the car body and bogie, and finally add pads at the primary spring position and the secondary empty spring position.

[0010] (3) Install a wheelset lift test device on the bogie and an attack angle test device on the twisted line;

[0011] Install laser displacement sensors at the axle box of the trailer and motor vehicle test bogies to test the wheel lift. Install photoelectric sensors at the axle ends of the trailer and motor vehicle test bogies, and stick reflective tapes radially at designated locations on the twisted line to test the wheel attack angle;

[0012] (4) Check the track and wheel conditions and confirm the most unfavorable load position;

[0013] Turn off the wheel flange lubrication device, confirm that the track and wheel are dry and grease-free, and take a video for archiving. According to the weighing report, confirm that the most unfavorable load position is on the outer rail of the curve.

[0014] (5) Conduct air and airless tests on twisted lines and evaluate the test results on site;

[0015] Carry out at least three gas tests, and then evaluate the gas test results on site. Thereafter, carry out at least three gas-free tests, and then evaluate the gas-free test results on site.

[0016] (6) Line status verification;

[0017] According to EN14363, the track needs to be reviewed after the test. The friction coefficient τ must be at least 80% of the track in dry conditions. The test can only be passed if the review is qualified. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the accompanying drawings.

[0019] Figure 1 The vehicle structure of the embodiment;

[0020] Figure 2 The dynamometric wheelset bridge assembly method of the embodiment;

[0021] Figure 3 The dynamometric wheelset of the embodiment;

[0022] Figure 4 Calibration of the dynamometric wheelset of the embodiment;

[0023] Figure 5 A padding method for an embodiment;

[0024] In the figure, ■ the bogie is twisted and padded; ● the car body is twisted and padded;

[0025] Figure 6 A wheelset lifting amount test tool according to an embodiment;

[0026] Figure 7 Arrangement of attack angle test points for an embodiment;

[0027] Figure 8 The attack angle test position of the embodiment;

[0028] Fig. 9 This is a test circuit for an embodiment. DETAILED DESCRIPTION

[0029] Different rail vehicles have different parameters, and the bogie and body distortion is also different. The following is a specific implementation method for a certain type of intercity EMU (3-unit). The vehicle structure is as follows: Figure 1 The test bogie is marked in black and is the first bogie for MC1 and T1.

[0030] 1. Production and calibration of dynamometer wheels;

[0031] like Figure 2 and Figure 3 In this test, a continuous force measuring wheelset was used to obtain the wheel-rail lateral force and wheel-rail vertical force, calculate the derailment coefficient, wheel weight reduction rate, etc., and conduct a derailment safety assessment.

[0032] The wheelset is double-sided pasted, two 5mm diameter wire holes are punched on the web, two 15mm diameter wire holes are punched on the axle to the hollow axle, and three M12 screw holes are punched on the axle end cover to fix the collector ring.

[0033] The calibration method of the dynamometer wheel pair is as follows: Figure 4 The four dynamometric wheelsets were calibrated on the dynamometric wheelset calibration platform, loaded step by step, and the transverse and vertical bridge output strains and actual wheel loads were collected to obtain the wheelset calibration coefficient matrix.

[0034] 2. Add padding to the car body and bogie;

[0035] Calculate the distortion of the car body and bogie with reference to EN14363, and calculate the padding thickness required to achieve the distortion of the car body and bogie.

[0036] According to the vehicle parameters, the distortion of the car body and bogie is calculated.

[0037] According to section 6.1.5.1.2 of standard EN14363, for bogie twisting:

[0038] When the wheelbase is 2a+≤4m,

[0039] When the wheelbase is 2a+>4m,

[0040] According to section 6.1.5.1.2 of standard EN14363, for body distortion:

[0041] When the vehicle spacing is 2a≤4m,

[0042] When the vehicle spacing is 4m<2a≤20m,

[0043] When the vehicle spacing is 20m<2a≤30m,

[0044] When the vehicle distance 2a>30m,

[0045] For the vehicle to be tested, the bogie wheelbase is 2.4m, so the bogie distortion is For the vehicle body, the vehicle spacing is 16.5m, then the distortion is

[0046] Calculate the wheel lift according to section A.7 of standard EN14363.

[0047] For bogie twist, the height of wheel lift

[0048] For vehicle body distortion, the height of wheel lift

[0049] where h + =(g + -g 0 )2a + ,h * =(g * -g 0 )2a * ;

[0050] where g + Indicates the bogie distortion; g * Indicates the amount of body distortion; g 0 Indicates the line distortion, where the line distortion is 0; 2b + is the lateral spacing of the left / right primary spring, in m; 2b * is the lateral spacing of the left / right secondary steel springs, in m; 2b A is the lateral distance between the left / right wheel-rail contact points, in meters;

[0051] In summary, for the test vehicle, the values ​​of various parameters are as follows.

[0052] Table 1 Calculation of pad thickness

[0053] <![CDATA[Wheelbase 2a + / m]]> 2.40 <![CDATA[Fixed distance 2a * / m]]> 16.50 <![CDATA[The lateral spacing 2b of the primary suspension spring + / m]]> 2.03 <![CDATA[Transverse spacing 2b of secondary suspension springs * / m]]> 1.92 <![CDATA[The distance 2b between the left and right wheel-rail contact points A / m]]> 1.50 Bogie twist g+ / ‰ 7.00 Body distortion g* / ‰ 3.21 <![CDATA[Line twist amount g 0 / ‰]]> 3.00 <![CDATA[h + / mm]]> 9.60 <![CDATA[h * / mm]]> 3.50 <![CDATA[The thickness d of the wheel set padding + / m]]> 6.50 <![CDATA[The thickness d of the vehicle body padding * / m]]> 2.24

[0054] According to EN14363, the bogie and car body are twisted by adding pads. The padding method is as follows Figure 5The bogie distortion is 7‰, the car body distortion is 3.2‰, and the track distortion is 3‰. After adding pads, the vehicle is weighed and a weighing report is generated. Before the test, it is necessary to confirm that the most unfavorable load position is on the outer rail side of the curve.

[0055] 3. Install the wheel lifting force measuring device and the attack angle testing device;

[0056] Wheel lift test method: Install a laser displacement sensor on the axle box to test the distance between the axle box and the rail top, i.e. the wheels lift. Install a laser displacement sensor on the axle end to test the wheels lift, as shown in the schematic diagram Figure 6 .

[0057] Install a photoelectric switch on the shaft end and paste a reflective label at the specified position of the line to test the wheel collision angle. Figure 7 .

[0058] Referring to Section 6.1.5.1.5 of EN14363, the attack angles at the following positions need to be output. Figure 8 In the test, the track distortion in area 2 first affects the whole vehicle, and the test interval should be less than 1.5m; the test interval in other areas should be less than 3m; when using a force measuring wheelset, the measurement position should be analogous to the above position.

[0059] Wheel angle of attack test method: Use reflective tape to mark the radial position of the curve, install photoelectric sensors on the axle boxes on the left and right sides of the wheelset, and when the left and right axle boxes pass through the reflective tape respectively, record the time difference between the two. Combined with the vehicle speed, the circumferential distance difference between the left and right wheels relative to the radial position of the curve can be obtained. Combined with the span of the two, the wheel angle of attack can be obtained.

[0060] 4. Check the condition of wheels and tracks and confirm the most unfavorable load position;

[0061] Check the track and wheel status, confirm that the track and wheels are dry, free of grease and debris, and take a video for archiving. Only when the wheels and tracks are dry and free of foreign matter, the wheel-rail friction coefficient is normal and the wheel-rail creep force is the most unfavorable state. Check the weighing records to confirm that the most unfavorable load position is on the outer rail side of the curve. During the test, the wheels on the outer side of the curve will climb the rails. Only when the minimum vertical force is on the outer rail of the curve is the most unfavorable vehicle load state.

[0062] 5 Formal test, on-site evaluation;

[0063] During the formal test, the derailment safety is calculated by measuring the wheel lift Δz of the outer wheel of the guide wheel when the vehicle passes through a twisted track, and the wheel-rail force index needs to be calculated at the same time.

[0064] 1) Test circuit

[0065] Torsion test line for derailment safety method 1 in accordance with EN14363 standard.

[0066] Line status: 3‰ twist, R150m, set line superelevation according to standard regulations, actual superelevation needs to be measured and recorded at each fastener position, line dry, such as Fig. 9 .

[0067] 2) Test conditions

[0068] Test load: empty vehicle (AW0) condition.

[0069] Empty spring state: with air + without air.

[0070] Number of tests: 3+3 times, this is the ideal number. If there are failures, the number of tests needs to be increased. The minimum number of successful tests is 3 times.

[0071] 3) Test speed

[0072] In order to minimize the impact of the longitudinal force of the train, the vehicle does not brake and passes at a constant speed, with a speed not exceeding 10km / h. The test is carried out on site by a locomotive, with a locomotive speed of about 5km / h, and the speed will fluctuate by ±2km / h.

[0073] 4) Driving direction

[0074] It is necessary to ensure that the motor car and the trailer have one bogie, that is, the test bogie is in front, because the guide wheel is in the worst condition.

[0075] The twisted line test includes both air-in and air-out conditions. The complete test process is shown in the following table. When the vehicle passes through the twisted line, the air spring cannot be inflated / deflated, so the height control valve needs to be isolated.

[0076] Table 2 Twist test implementation sequence

[0077]

[0078] 6. Trial evaluation criteria;

[0079] Derailment safety is calculated by measuring the wheel lift Δz of the outer wheel of the guide wheel when the vehicle passes through the twisted track. (Y / Q) a Will be measured, (Y / Q) a,max will be calculated and included in the report, but (Y / Q) a，max It is not an assessment quantity.

[0080] The maximum wheelset lift of the outer rail wheel is less than 5mm, which should be satisfied in all three tests; the three successful tests do not have to be consecutive, but if two consecutive tests fail, the test will not be passed; if the wheelset lift is greater than the limit, the Y / Q of the outer rail should be checked. If Y / Q is less than 1.12, the test should be repeated.

[0081] This test uses the wheel-rail force direct measurement method to obtain the wheel-rail force. The output safety indicators are: derailment coefficient, wheel axle lateral force, wheel-rail vertical force. The specific limits are as follows:

[0082] Derailment coefficient:

[0083] [(Y / Q) 2m ] lim =0.8

[0084] Where: Y represents the wheel-rail lateral force, Q represents the wheel-rail vertical force, Y / Q represents the derailment coefficient, and "2m" represents the smoothing distance. For specific limit values, see standard EN14363-2016.

[0085] Axle lateral force:

[0086]

[0087] Where ∑Y2m represents the sum of the lateral forces of the guide wheel and rail calculated using 2m smoothing; for locomotives, passenger cars (EMU and trailers), and track maintenance vehicles, α is taken as 1; P0 is the static axle weight in kN; for specific limit values, see standard EN14363-2016.

[0088] Wheel-rail vertical force:

[0089] Q≤Q0+90

[0090] Where Q0 represents the static wheel weight in kN; see standard EN14363-2016 for specific limits.

[0091] 7. Line status check:

[0092] According to EN14363, the track needs to be reviewed after the test. The friction coefficient τ is at least 80% of the track in dry conditions. The track needs to meet the following formula:

[0093] (Y / Q) i ≥0.8·τ dry +γ

[0094] Among them, α is the wheel angle of attack (unit: rad), γ is the contact angle (the contact angle of the inner rail contact point of the guide wheel), Q0 is the static vertical force (unit: kN), τ dry It can be calculated using Q0 according to the following formula.

[0095]

[0096] where

[0097]

[0098] n=0,005Q0+2,2.

Claims

1. The torsion test method that meets the EN14363 standard is characterized by: It includes the following steps: (1) Prepare four dynamometric wheel sets, two moving and two trailing; The test uses a continuous force measuring wheelset to obtain the wheel-rail lateral force and wheel-rail vertical force, calculate the derailment coefficient, wheel load reduction rate, etc., and conduct a derailment safety assessment; (2) Adding pads to the bogies causes distortion of the bogies and car bodies; Calculate the distortion of the car body and bogie according to EN14363, calculate the pad thickness required to achieve the distortion of the car body and bogie, and finally add pads at the primary spring position and the secondary empty spring position; (3) Install a wheelset lift test device on the bogie and an attack angle test device on the twisted line; Install laser displacement sensors at the axle box of the trailer and EMU test bogies to test the wheel lift; install photoelectric sensors at the axle ends of the trailer and EMU test bogies, and stick reflective tapes radially at designated locations on the twisted line to test the wheel attack angle; (4) Check the track and wheel conditions and confirm the most unfavorable load position; Turn off the wheel flange lubrication device, confirm that the rails and wheels are dry and grease-free, and take a video for archiving; confirm that the most unfavorable load position is on the outer rail of the curve according to the weighing report; (5) Conduct air and airless tests on twisted lines and evaluate the test results on site; Conduct at least three gas tests, and then evaluate the gas test results on site; thereafter, conduct at least three gas-free tests, and evaluate the gas-free test results on site; (6) Line status verification; According to EN14363, the track must be reviewed after the test, and the friction coefficient τ must be at least 80% of the track in dry conditions. The test can only be passed if the review is qualified.

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