A rail profile grinding scheme design method based on personalized pattern library

Abstract

The present invention discloses a rail profile grinding scheme design method based on a personalized pattern library. First, according to the measured rail profile, the target profile and the personalized pattern library, the equivalent deviation index of the rail profile before grinding is calculated; further, according to the metal cutting theory, the rail profile, the equivalent deviation index and the maximum negative deviation after each mode grinding are calculated. Then, according to the constraint conditions that the equivalent deviation index of the rail is gradually reduced after each grinding and the maximum negative deviation value does not exceed the allowable value, the grinding mode that meets the requirements is preliminarily screened out, and the optimal grinding mode is determined according to the principle of the lowest equivalent deviation index, and the number of each grinding mode is obtained. Finally, the rail profile and the equivalent deviation index after each grinding are determined. The grinding modes of each grinding pass and the rail profile after grinding are calculated by the above method; finally, the grinding scheme is determined and the rail profile after each grinding pass is predicted. The present invention can conveniently and efficiently design a rail profile grinding scheme and predict the rail profile after grinding.

Description

Technical Field

[0001] The invention belongs to the technical field of rail grinding, and relates to a rail profile grinding scheme design method based on a personalized pattern library. Background Art

[0002] With the continuous development of the economy and society, the scale of my country's railway network has continued to expand and improve, and railway operations are also developing rapidly in the direction of "high speed and large capacity", which has put forward higher requirements for railway maintenance and repair. As an important core component of the track structure, the rail bears and transmits the complex and variable loads imposed by the train and provides guidance for the train. As the time on the track increases, the service condition of the rail gradually deteriorates, which will lead to poor rail profile condition, and then induce the occurrence and deterioration of diseases. If the rail profile and diseases are not treated in a timely and effective manner, it may cause shaking and swaying of the train, which will endanger driving safety in severe cases and cost high maintenance and repair costs.

[0003] Rail profile grinding is an effective means to repair rail profile and treat rail diseases in service. It can control the occurrence and development of diseases from the root and extend the service life of rails. At present, large-scale grinding trains and small-scale grinding equipment are commonly used for rail grinding operations at home and abroad, and a plan design is required before grinding. The grinding plan is an important basis for guiding on-site grinding operations. If the grinding plan design is unreasonable, it will directly affect the grinding quality and the grinding effect will be difficult to guarantee. Summary of the invention

[0004] In view of the above problems, in order to provide effective guidance for on-site grinding operations and ensure the grinding quality, the present invention proposes a rail profile grinding scheme design method based on a personalized pattern library. According to the measured rail profile, target profile and personalized pattern library, a certain mathematical algorithm is used to conveniently and efficiently design the rail profile grinding scheme and predict the rail profile after grinding.

[0005] The present invention proposes a rail profile grinding scheme design method based on a personalized pattern library, which is implemented through the following steps:

[0006] Step 1: Align the rail measurement profile with the grinding target profile based on the principle of minimum grinding amount.

[0007] Step 2: According to the grinding mode requirements of the grinding car, compile a personalized grinding mode library, or directly use the built-in mode library of the grinding car.

[0008] Step 3: Calculate the equivalent deviation index of the rail shape before grinding based on the measured rail profile and the target profile before grinding.

[0009] Step 4: Based on the rail profile before grinding, calculate the rail profile, equivalent deviation index and maximum negative deviation after grinding in each mode.

[0010] Step 5: Based on the constraints that the rail equivalent deviation index gradually decreases after each grinding and the maximum negative deviation value does not exceed the allowable value, a grinding mode that meets the requirements is preliminarily screened out.

[0011] Step 6: Determine the optimal grinding mode according to the principle of minimum equivalent deviation index, and obtain the grinding mode number of each pass.

[0012] Step 7: According to the optimal grinding mode determined in step 6, the rail profile and equivalent deviation index after each grinding are determined.

[0013] Step 8: Execute the above steps 3 to 7 in a loop, calculate the grinding mode of each pass and the rail profile after grinding, and record the number of grinding passes required.

[0014] Step 9: Determine the grinding plan and obtain the predicted rail profile after each grinding.

[0015] The advantages of the present invention are:

[0016] 1. The grinding scheme design is efficient and the calculation speed is fast. The present invention innovatively proposes a calculation method for the equivalent deviation index of the rail profile and uses it as an evaluation index for rail profile grinding. The calculation method is simple and can effectively characterize the necessary degree of rail profile grinding. At the same time, reasonable model preliminary screening constraints and grinding calculation termination conditions are set to avoid excessive calculation.

[0017] 2. It can accurately predict the rail profile after grinding and effectively guide the grinding operation. While determining each grinding mode, the present invention can calculate the rail profile after each grinding, which helps to strengthen the process prediction and control of the grinding operation and provide a reference for the on-site implementation of the grinding operation and the optimization of the scheme.

[0018] 3. Support the compilation of personalized pattern library to improve the quality of grinding pattern. The present invention can compile a personalized pattern library according to factors such as grinding vehicle performance, operation quality requirements, and line status, which can effectively ensure that the angle transition of the grinding pattern is reasonable and the angle division is appropriate, thereby ensuring the quality of the grinding pattern and meeting the differentiated needs of different grinding vehicles and grinding equipment.

[0019] 4. Wide application scope and broad application prospects. The present invention can be applied to most of the current grinding vehicles and grinding equipment at home and abroad, and can provide them with efficient grinding solutions. At the same time, the invention can also be applied to the vehicle-mounted grinding solution design system to realize the real-time design of the grinding solution and synchronous grinding operation, effectively improve the intelligence, automation and digitization of grinding vehicles and grinding equipment, and has broad application prospects.

[0020] 5. Convenient for programmed calculation and easy to implement mass grinding scheme design. The present invention provides a programmed calculation process, which is convenient for programming and can quickly complete the design of mass rail profile grinding schemes, thereby simplifying the grinding scheme design method and reducing the difficulty of grinding scheme design.

[0021] 6. Profile grinding can be achieved to improve the quality of rail grinding. The present invention is guided by the target profile to be ground. Each grinding can gradually make the rail profile fit the target profile. Through reasonable pattern library configuration and termination condition selection, the rail profile can be quickly matched with the designed profile, thereby improving the rail grinding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is an overall flow chart of the rail profile grinding scheme design method based on the personalized pattern library.

[0023] Figure 2 Schematic diagram of the alignment between the measured rail profile and the target profile.

[0024] Figure 3 Schematic diagram of the personalized polishing pattern library.

[0025] Figure 4 Calculate the flow chart for each pass sanding mode.

[0026] Figure 5 Schematic diagram of the calculation area for rail profile equivalent deviation index.

[0027] Figure 6 Schematic diagram comparing the predicted rail profile after grinding and before grinding. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings.

[0029] The present invention provides a rail profile grinding scheme design method based on a personalized pattern library, such as Figure 1 As shown, the following steps are included:

[0030] Step 1: Align the measured rail profile with the designed target profile.

[0031] According to the line conditions, rail status, disease conditions, grinding requirements and other factors, the measured rail profile is aligned with the grinding target according to the principle of minimum grinding amount, so as to determine the position and grinding amount of the rail to be ground for subsequent calculations. The example after profile alignment is as follows Figure 2 As shown. Figure 2 It can be seen that the two sides of the measured profile rail top are obviously higher than the target profile, so it is necessary to grind both sides of the rail top to make the measured profile consistent with the designed profile.

[0032] Step 2: Compile a personalized polishing pattern library.

[0033] According to the grinding mode requirements of the grinding car, a personalized grinding mode library can be compiled, or the built-in mode library of the grinding car can be directly used. The mode library example is as follows Figure 3 As shown. Usually, each grinding mode includes parameters such as the grinding angle / position of each grinding head, the grinding power / pressure / current of each grinding head, and the operating speed of the grinding vehicle. The types of grinding modes in the mode library should be as rich as possible to meet the needs of grinding different positions of the rail.

[0034] Step 3: Calculate the equivalent deviation index of the rail profile before grinding.

[0035] like Figure 4 As shown in the figure, according to the measured rail profile RC before the i-th grinding i-1 and the target profile RT, calculate the equivalent deviation index RED of the rail profile before the i-th grinding i-1 When calculating the equivalent deviation index of rail profile, the main wheel-rail contact area on the rail top is first divided into X small areas along the horizontal coordinate direction of the rail profile, such as Figure 5 As shown, the weight coefficient of each region is G u (where u = 1, 2, 3, ..., X); then, each small area is discretized according to the same arc length (the arc length can be selected according to the calculation accuracy), and the number of discrete points in each small area is Y u (where u = 1, 2, 3, ..., X), then the normal deviation at each discrete point in the u-th small interval is d uw (where u=1, 2, 3,..., X; w=1, 2, 3,..., Y u ). Therefore, the equivalent deviation index RED is:

[0036]

[0037] The closer the equivalent deviation index is to 0, the closer the measured profile is to the target profile.

[0038] Step 4: Calculate the rail profile, equivalent deviation index and maximum negative deviation corresponding to each grinding mode

[0039] (1) Assuming that there are n types of grinding modes in the personalized mode library, according to metal cutting theory, the measured rail profile RC before grinding is i-1 Based on the above, the rail profile RC after the i-th grinding using each grinding mode is calculated respectively. ij (where j represents the jth grinding mode in the mode library, j = 1, 2, 3, ..., n). For example, when the equal-area grinding assumption is used for calculation, the grinding area S of a single grinding head is:

[0040]

[0041] Among them, P is the grinding head motor power; H is the rail hardness; V is the grinding speed; Q is the speed index; T is the empirical adjustment coefficient. According to the grinding area S of a single grinding head and the angle arrangement of the grinding head in each mode, the profile of the rail after grinding can be simulated and calculated.

[0042] (2) According to the rail profile RC after the i-th grinding ij and target profile RT, the rail profile equivalent deviation index RED after each grinding mode is calculated according to formula (1): ij and maximum negative deviation MND ij The so-called maximum negative deviation is the maximum normal deviation value of the rail profile after grinding below the target profile in the main wheel-rail contact area at the rail top (the measured profile is lower than the target profile). If the rail profile after grinding is lower than the target profile in the main wheel-rail contact area at the rail top, the maximum negative deviation MND ij is positive; if the rail profile after grinding is higher than the target profile in the main wheel-rail contact area at the rail top, the maximum negative deviation MND ij is negative.

[0043] Step 5: Preliminary screening of grinding modes that meet the constraints

[0044] In order to make the rail profile after grinding gradually fit the target profile, it is necessary to gradually reduce the rail equivalent deviation index after each grinding. In order to avoid over-grinding, the maximum negative deviation value MND should also be met. ij Not exceeding the permitted value MND L In order to meet the above constraints, the grinding modes that meet the conditions are preliminarily screened out according to formula (3).

[0045]

[0046] If there is a grinding pattern that satisfies formula (3), the subsequent calculation will continue; if there is no grinding pattern that satisfies formula (3), it means that the i-th grinding is not required, and the calculation will be terminated. At this time, the corresponding grinding pattern can be added to the pattern library to satisfy the constraint condition of formula (3) so that the grinding calculation can be continued, thereby further increasing the fit between the measured profile and the target profile. Figure 4 Where k is the number of grinding modes that meet the initial screening conditions. Figure 4 The constraints are formalized in the formula.

[0047] Step 6: Get the optimal grinding mode for each pass and determine the mode number

[0048] In the above step 5, the grinding mode that meets the constraint conditions is initially screened, and the equivalent deviation index RED is ijThe grinding mode corresponding to the lowest value is determined as the optimal grinding mode and is used as the i-th grinding mode. The i-th grinding mode determined in this step is numbered as N. i .

[0049] Step 7: Determine the rail profile and equivalent deviation index after each grinding pass

[0050] Combine the calculation result of step 4 and the mode number N determined in step 6 i According to the metal cutting theory (such as the equal area grinding assumption), the rail profile RC after the i-th grinding is calculated. i , calculate the effective deviation index RED according to formula (1) i .

[0051] Step 8: Calculate the optimal grinding mode and rail profile after grinding for each grinding pass

[0052] According to the rail measurement profile, target profile and personalized grinding mode library, the above steps 3 to 7 are executed in sequence until the equivalent deviation index RED of the rail profile after grinding is i Less than the allowed value RED L The calculation is terminated when , and the number of passes required for grinding is recorded as K. The grinding calculation termination condition is shown in formula (4).

[0053] RED i <RED L (4)

[0054] Step 9: Determine the grinding plan and predict the profile

[0055] According to the calculation results of the above steps 7 and 8, the rail grinding scheme can be determined by combining the grinding mode and profile data of each pass, and the predicted rail profile after each grinding can be obtained. The grinding scheme example is shown in Table 1. In Table 1, K is the number of grinding passes determined by the above calculation. The comparison between the rail profile after grinding and before grinding is shown in the figure Figure 6 shown.

[0056] Table 1 Rail grinding scheme and predicted profile examples

[0057]

Claims

1. A rail profile grinding scheme design method based on a personalized pattern library, characterized in that: This is accomplished by: Step 1: Align the rail measurement profile with the grinding target profile according to the principle of minimum grinding amount; Step 2: According to the grinding mode requirements of the grinding car, compile a personalized grinding mode library, or directly use the built-in mode library of the grinding car; Step 3: Calculate the equivalent deviation index of the rail profile before grinding according to the measured rail profile and the target profile before grinding; Step 4: Based on the rail profile before grinding, the rail profile, equivalent deviation index and maximum negative deviation after grinding in each mode are calculated respectively; Step 5: Based on the constraints that the rail equivalent deviation index gradually decreases after each grinding and the maximum negative deviation value does not exceed the allowable value, a grinding mode that meets the requirements is preliminarily selected; Step 6: Determine the optimal grinding mode according to the principle of minimum equivalent deviation index, and obtain the grinding mode number of each pass; Step 7: According to the optimal grinding mode determined in step 6, the rail profile and equivalent deviation index after each grinding are determined; Step 8: cyclically execute the above steps 3 to 7, calculate the grinding mode of each pass and the rail profile after grinding, and record the number of grinding passes required; Step 9: Determine the grinding plan and obtain the predicted rail profile after each grinding.

2. A rail profile grinding scheme design method based on a personalized pattern library as claimed in claim 1, characterized in that: In step 3, the calculation method of the equivalent deviation index of the rail profile before grinding is as follows: first, the main wheel-rail contact area on the rail top is divided into X areas along the horizontal coordinate direction of the rail profile, and the weight coefficient of each area is G u , u=1, 2, 3, ..., X; then, each small area is discretized according to the same arc length, and the number of discrete points in each small area is Y u , where u = 1, 2, 3, ..., X, then the normal deviation at each discrete point in the u-th interval is d uw , where u=1, 2, 3,...,X; w=1, 2, 3,...,Y u ; Therefore, the equivalent deviation index RED 3. A rail profile grinding scheme design method based on a personalized pattern library as claimed in claim 1, characterized in that: The corresponding rail profile, equivalent deviation index and maximum negative deviation after grinding in each mode are calculated through metal cutting theory: First, let there be n grinding modes in the personalized mode library. According to the metal cutting theory, the actual measured profile RC of the rail before grinding is respectively i-1 Based on the above, the rail profile RC after the i-th grinding using each grinding mode is calculated respectively. ij , where j represents the jth polishing mode in the mode library, j = 1, 2, 3, ..., n; Then, according to the rail profile RC after the i-th grinding ij and target profile RT, calculate the rail profile equivalent deviation index RED after each grinding mode ij and maximum negative deviation MND ij ; The maximum negative deviation is the maximum normal deviation of the rail profile after grinding below the target profile in the main wheel-rail contact area at the rail top; if the rail profile after grinding is lower than the target profile in the main wheel-rail contact area at the rail top, the maximum negative deviation MND ij is positive; if the rail profile after grinding is higher than the target profile in the main wheel-rail contact area at the rail top, the maximum negative deviation MND ij is negative.

4. A rail profile grinding scheme design method based on a personalized pattern library as claimed in claim 1, characterized in that: In step 5, if there is no polishing pattern that satisfies the constraint conditions, the calculation is terminated or a corresponding polishing pattern is added to the pattern library to satisfy the constraint conditions.

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