Rail surface fatigue damage degree evaluation method based on rating atlas

Abstract

The application provides a rail surface fatigue damage degree evaluation method based on a rating atlas, relates to the field of railway maintenance technology, and comprises the following steps: preparing a rail surface fatigue damage rating atlas; obtaining a photo of the rail surface of a rail to be evaluated; comparing the photo with the rail surface fatigue damage rating atlas; and determining the rail surface fatigue damage degree grade of the rail to be evaluated according to the rail surface fatigue damage rating atlas. The rail surface fatigue damage degree evaluation method based on the rating atlas can quickly determine the rail surface fatigue damage degree at a maintenance site, and provides a scientific decision basis for subsequent polishing and maintenance processes.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of railway maintenance technology, in particular to a rail surface fatigue damage degree evaluation method based on a rating atlas. BACKGROUND

[0002] The rail surface directly bears the wheel, and when the local contact stress is too large due to poor profile matching or deteriorating load conditions between the wheel and the rail, rolling contact fatigue (RCF) damage is easily generated.

[0003] Rolling contact fatigue damage is usually manifested as rail surface fish scales (as shown in Figure 1 ), chipping (as shown in Figure 2 ), etc., and its harm lies in: 1. The crack develops downward and evolves into a longitudinal and transverse crack type core damage, which further causes rail breakage; 2. Rail surface damage affects ultrasonic inspection of internal core damage of the rail, leading to false detection or missed detection; 3. When the rail surface chipping is large, it causes local impact load of the wheel and accelerates crack propagation. It can be seen that the rolling contact fatigue damage of the rail surface has certain harmfulness to railway transportation safety.

[0004] For rail surface contact fatigue damage, it is generally alleviated by reasonable matching of wheel and rail hardness and profile, and application of rail grinding repair technology, but it cannot be fundamentally eliminated. When the rail is ground and repaired, the grinding maintenance decision and strategy need to be made according to the degree of rail surface rolling contact fatigue damage. At present, eddy current detection and ultrasonic detection are mainly used to detect the rail to obtain the rolling contact fatigue damage of the rail surface, but both methods have their own technical limitations, and more importantly, they need to carry professional measuring equipment, which is not convenient for on-site maintenance personnel to use directly.

[0005] In view of this, the present application is designed by the present inventor on the basis of years of production and design experience in this field and related fields, and after repeated tests, a rail surface fatigue damage degree evaluation method based on a rating atlas is designed to solve the problems existing in the prior art. SUMMARY

[0006] The purpose of the present application is to provide a rail surface fatigue damage degree evaluation method based on a rating atlas, which can quickly determine the degree of rail surface fatigue damage at the repair site and provide a scientific decision basis for the subsequent grinding and repair process.

[0007] To achieve the above-mentioned purpose, the present application provides a rail surface fatigue damage degree evaluation method based on a rating atlas, wherein the rail surface fatigue damage degree evaluation method comprises:

[0008] Manufacture a rail surface fatigue damage rating atlas;

[0009] acquire a photo of a rail surface of a steel rail to be evaluated;

[0010] compare the photo with a rail surface fatigue damage rating atlas of the steel rail, and determine a rail surface fatigue damage degree grade of the steel rail to be evaluated according to the rail surface fatigue damage rating atlas of the steel rail.

[0011] Compared with the prior art, the rail surface fatigue damage degree evaluation method based on the rating atlas has the following characteristics and advantages:

[0012] The rail surface fatigue damage degree evaluation method based on the rating atlas has the following characteristics and advantages: The rail surface fatigue damage degree evaluation method based on the rating atlas has the following characteristics and advantages: BRIEF DESCRIPTION OF DRAWINGS

[0013] The drawings described herein are for the purpose of explanation and are not intended to limit the scope of the present disclosure in any way. Additionally, the shapes and proportions of the components in the drawings are merely illustrative and are used to facilitate the understanding of the present disclosure, and are not specifically limited to the shapes and proportions of the components. Those skilled in the art can select various possible shapes and proportions according to specific circumstances to implement the present disclosure under the guidance of the present disclosure.

[0014] Figure 1 is a 0-grade rail surface fatigue damage standard atlas in the present application;

[0015] Figure 2 is a 1-grade rail surface fatigue damage standard atlas (upper curve) in the present application;

[0016] Figure 3 is a 1-grade rail surface fatigue damage standard atlas (lower curve) in the present application;

[0017] Figure 4 is a 2-grade rail surface fatigue damage standard atlas (upper curve) in the present application;

[0018] Figure 5 is a 2-grade rail surface fatigue damage standard atlas (lower curve) in the present application;

[0019] Figure 6 is a 3-grade rail surface fatigue damage standard atlas (upper curve) in the present application;

[0020] Figure 7It is the standard graph of fatigue damage of rail surface (curve upper limb) of the third grade rail in the application;

[0021] Figure 8 It is the standard graph of fatigue damage of rail surface (curve upper limb) of the fourth grade rail in the application;

[0022] Figure 9 It is the standard graph of fatigue damage of rail surface (curve lower limb) of the fourth grade rail in the application;

[0023] Figure 10 It is the standard graph of fatigue damage of rail surface (curve upper limb) of the fifth grade rail in the application;

[0024] Figure 11 It is the standard graph of fatigue damage of rail surface (curve lower limb) of the fifth grade rail in the application;

[0025] Figure 12 It is the standard graph of fatigue damage of rail surface (curve upper limb) of the sixth grade rail in the application;

[0026] Figure 13 It is the standard graph of fatigue damage of rail surface (curve lower limb) of the sixth grade rail in the application;

[0027] Figure 14 It is the standard graph of fatigue damage of rail surface (curve upper limb) of the seventh grade rail in the application;

[0028] Figure 15 It is the standard graph of fatigue damage of rail surface (curve lower limb) of the seventh grade rail in the application;

[0029] Figure 16 It is the flow chart of the rail surface fatigue damage degree evaluation method based on the rating atlas proposed in the application. DETAILED DESCRIPTION

[0030] The details of the application can be more clearly understood in conjunction with the accompanying drawings and the description of the specific embodiments of the application. However, the specific embodiments of the application described herein are only for the purpose of explaining the application, and should not be understood in any way as limiting the application. Based on the teachings of the application, a skilled person can conceive any possible modification based on the application, which should be considered as falling within the scope of the application.

[0031] As shown in Figure 16 The application proposes a rail surface fatigue damage degree evaluation method based on a rating atlas, which comprises:

[0032] making a rail surface fatigue damage rating atlas;

[0033] obtaining a photo of the rail surface of the rail to be evaluated;

[0034] The photo is compared with a rail surface fatigue damage rating atlas, and the rail surface fatigue damage degree of the rail to be evaluated is determined according to the rail surface fatigue damage rating atlas.

[0035] The rail surface fatigue damage degree evaluation method based on the rating atlas can help the railway maintenance department front-line operating personnel to evaluate the rail surface damage degree of the rail without special damage detection equipment and capability, provide a decision basis for the development of the rail grinding strategy, and help to change the current periodic repair into state repair, and realize scientific and effective allocation of the rail grinding resources.

[0036] In an optional embodiment of the present application, the rail surface fatigue damage rating atlas is made, comprising: determining the rail surface fatigue damage degree according to the characteristics and damage density of the rail surface damage, and making the rail surface fatigue damage standard atlas corresponding to each degree.

[0037] In an optional example of the embodiment, the rail surface fatigue damage degree comprises 0-7 degrees, and the rail surface fatigue damage rating atlas comprises 0-7 degree rail surface fatigue damage standard atlas.

[0038] In an optional example of the embodiment, the 0-7 degree rail surface fatigue damage standard atlas is respectively:

[0039] The 0 degree rail surface fatigue damage standard atlas has no crack and no spalling on the rail surface.

[0040] The 1 degree rail surface fatigue damage standard atlas has cracks on the rail surface and no spalling.

[0041] The 2 degree rail surface fatigue damage standard atlas has cracks on the rail surface and sporadic and slight spalling.

[0042] The 3 degree rail surface fatigue damage standard atlas has cracks on the rail surface and continuous and slight spalling.

[0043] The 4 degree rail surface fatigue damage standard atlas has cracks on the rail surface, continuous and slight spalling, and sporadic and large size spalling.

[0044] The 5 degree rail surface fatigue damage standard atlas has cracks on the rail surface, and strip-shaped and continuous large size spalling.

[0045] The 6 degree rail surface fatigue damage standard atlas has cracks on the rail surface, and continuous and large size spalling distributed on the top surface.

[0046] 7-grade rail surface fatigue damage standard map, the rail surface of which has cracks and large-size spalling that is distributed across the top surface and continuously distributed, or the length of a single spalling is ≥ 25 mm.

[0047] In an alternative example of this embodiment, the rail surface fatigue damage degree of the rail to be evaluated is determined according to the rail surface fatigue damage rating map, which includes: when the characteristics and damage density of the rail surface damage in the photo are close to the n-grade rail surface fatigue damage standard map in the rail surface fatigue damage rating map, it is determined that the rail surface fatigue damage degree of the rail to be evaluated is n-grade; when the characteristics and damage density of the rail surface damage in the photo are between the n-grade rail surface fatigue damage standard map and the n+1-grade rail surface fatigue damage standard map, it is determined that the rail surface fatigue damage degree of the rail to be evaluated is n.5-grade, wherein n is 0-7.

[0048] In an alternative example of this embodiment, the size of the slight spalling is 5 mm ≤ spalling length < 15 mm; the size of the large-size spalling is 5 mm ≤ spalling length < 25 mm.

[0049] In an alternative example of this embodiment, sporadic distribution refers to a distance between two adjacent spallings being greater than 300 mm; continuous distribution refers to a distance between two adjacent spallings being greater than 300 mm; strip-shaped and continuous distribution refers to an average width of the spalling area being greater than 15 mm; and distribution across the top surface and continuously refers to an average width of the spalling area being greater than 50 mm.

[0050] In an alternative example of this embodiment, the resolution of the photo of the rail to be evaluated is not less than 1080p.

[0051] In an alternative example of this embodiment, the photo of the rail to be evaluated should cover at least 0.5 meters of the length of the rail.

[0052] Now, an embodiment will be combined to explain the specific implementation process of the rail surface fatigue damage degree evaluation method based on the rating map proposed in the present application in detail.

[0053] In this embodiment, the rail surface fatigue damage can be divided into eight grades: none (0-grade); slight I-grade (1-grade); slight II-grade (2-grade); moderate I-grade (3-grade); moderate II-grade (4-grade); severe I-grade (5-grade); severe II-grade (6-grade); and severe III-grade (7-grade). Correspondingly, the rail surface fatigue damage rating map includes eight (0-7-grade) rail surface fatigue damage standard maps.

[0054] Specifically, 0-grade rail surface fatigue damage, i.e., no rail surface fatigue damage, is characterized by no cracks, spalling, and other fatigue damage. Correspondingly, as shown in FIG. 1, the 0-grade rail surface fatigue damage standard map is a rail surface without fatigue damage. Figure 1As shown, the standard diagram of fatigue damage on the surface of a Grade 0 rail shows that the rail surface has no cracks and no spalling.

[0055] Grade 1 rail surface fatigue damage, also known as minor Grade I rail surface fatigue damage, is characterized by the presence of cracks, without a rough feel or spalling. Correspondingly, such as... Figure 2 , Figure 3 As shown in the figure, the standard diagram of fatigue damage on the surface of a Class 1 rail shows that the rail surface has cracks but no spalling.

[0056] Grade 2 rail surface fatigue damage, also known as minor Grade II rail surface fatigue damage, is characterized by the presence of cracks, a rough feel, and scattered minor spalling. Correspondingly, such as... Figure 4 , Figure 5 As shown in the standard diagram of fatigue damage to the rail surface of a Class 2 rail, there are cracks on the rail surface and scattered minor chips.

[0057] Grade 3 rail surface fatigue damage, also known as medium Grade I rail surface fatigue damage, is characterized by the presence of cracks, a rough feel, and continuously distributed minor spalling. Correspondingly, such as... Figure 6 , Figure 7 As shown in the standard diagram of fatigue damage to the rail surface of a Class 3 rail, the rail surface has cracks and continuous, slightly fragmented pieces.

[0058] Grade 4 rail surface fatigue damage, also known as medium Grade II rail surface fatigue damage, is characterized by the presence of cracks, a rough feel, continuous distribution of small spallings, and sporadic distribution of larger spallings, with individual spalling lengths ranging from 5mm to 15mm. Correspondingly, such as... Figure 8 , Figure 9 As shown in the standard diagram of fatigue damage to the rail surface of a Class 4 rail, the rail surface has cracks, and there are continuous minor chips and scattered larger chips.

[0059] Grade 5 rail surface fatigue damage, also known as severe Grade I rail surface fatigue damage, is characterized by the presence of cracks, a rough feel, and large, continuously distributed strip-shaped spallings on the rail top surface. Individual spallings are 15mm ≤ length < 25mm, the furthest distance between two adjacent spallings is less than 300mm, and the average width of the spalling area is greater than 15mm. Correspondingly, such as... Figure 10 , Figure 11 As shown in the standard diagram of fatigue damage to the surface of a Grade 5 rail, the rail surface has cracks and large-sized spalling blocks that are distributed in strips and continuously.

[0060] Grade 6 rail surface fatigue damage, also known as severe Grade II rail surface fatigue damage, is characterized by cracks, a rough feel, and large, continuously distributed spallings across the rail top surface, with individual spalling lengths ranging from 15mm to 25mm. Correspondingly, such as... Figure 12 , Figure 13As shown in the figure, the rail surface fatigue damage standard diagram of the 6th grade rail has cracks and large size spalling continuously distributed on the top surface.

[0061] The 7th grade rail surface fatigue damage, i.e., severe 3rd grade rail surface fatigue damage, is characterized by cracks, a sharp feeling, large size spalling continuously distributed on the top surface of the rail, and the length of a single spalling being greater than or equal to 25 mm. Correspondingly, as shown in the figure, Figure 14 、 Figure 15 the rail surface fatigue damage standard diagram of the 7th grade rail has cracks and large size spalling continuously distributed on the top surface, or the length of a single spalling is greater than or equal to 25 mm.

[0062] In the embodiment, the operation steps of the rail surface fatigue damage degree evaluation method include:

[0063] First, take a picture of the rail surface; use a camera to take a picture of the rail head top surface under the condition of daytime light, and the picture should cover at least 0.5 meters of the rail, and the resolution of the picture should not be lower than 1080p, so as to ensure that the rail surface damage is clear.

[0064] Then, compare with the atlas to evaluate the grade; compare the rail surface damage picture with the evaluation atlas, specifically,

[0065] when the characteristics and density of the rail surface damage are close to the nth grade in the evaluation atlas, the rail surface damage at this position can be evaluated as the nth grade;

[0066] when the rail surface damage degree is between the nth grade and the n+1th grade in the evaluation atlas, the rail surface damage at this position can be evaluated as the n+0.5th grade.

[0067] The rail surface fatigue damage degree evaluation method based on the evaluation atlas provided by the present application is helpful for the front-line operating personnel of the railway maintenance department to evaluate the rail surface damage degree of the line rail under the condition that they do not have special detection equipment and ability, to provide a decision basis for the formulation of the rail grinding strategy, and to be beneficial to the change of the current periodic repair to the state repair for the rail grinding, so as to realize the scientific and effective allocation of the rail grinding resources.

[0068] The detailed explanations of the above-mentioned embodiments are only for the purpose of explaining the present application, so as to facilitate better understanding of the present application, but these descriptions cannot be explained as limitations of the present application for any reason, and in particular, the various features described in different embodiments can be arbitrarily combined with each other to form other embodiments, and these features should be understood as being applicable to any one embodiment, rather than being limited to the described embodiments.

Claims

1. A method for evaluating the degree of fatigue damage of a rail head based on a rating map, characterized by, The rail surface fatigue damage degree evaluation method comprises: making a rail surface fatigue damage rating atlas; determining the rail surface fatigue damage grade according to the characteristics and damage density of the rail surface damage, and making a rail surface fatigue damage standard atlas corresponding to each grade; the rail surface fatigue damage grade comprises 0-7 grades, and the rail surface fatigue damage rating atlas comprises 0-7 rail surface fatigue damage standard atlases; the 0-7 rail surface fatigue damage standard atlas comprises: a 0-grade rail surface fatigue damage standard atlas, wherein the rail surface is free of cracks and spalling; a 1-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks and is free of spalling; a 2-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks and sporadic and slight spalling; a 3-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks and continuous and slight spalling; a 4-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks, continuous and slight spalling, and sporadic and large-size spalling; a 5-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks and strip-shaped and continuous large-size spalling; a 6-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks and continuous and large-size spalling covering the top surface; a 7-grade rail surface fatigue damage standard atlas, wherein the rail surface has cracks and continuous and large-size spalling covering the top surface, or the length of a single spalling is greater than or equal to 25 mm; the sporadic distribution refers to a distance between two adjacent spallings being greater than 300 mm; the continuous distribution refers to a distance between two adjacent spallings being less than 300 mm; the strip-shaped and continuous distribution refers to an average width of a spalling area being greater than 15 mm; and the continuous and large-size spalling covering the top surface refers to an average width of a spalling area being greater than 50 mm; obtaining a photo of the rail surface of a rail to be evaluated; comparing the photo with the rail surface fatigue damage rating atlas, and determining the rail surface fatigue damage degree of the rail to be evaluated according to the rail surface fatigue damage rating atlas.

2. The rating map-based rail head fatigue damage level evaluation method of claim 1, wherein, the slight spalling has a size of 5 mm≤spalling length<15 mm; and the large-size spalling has a size of 5 mm≤spalling length<25 mm.

3. The rating map based rail head fatigue damage assessment method of claim 1 wherein, comparing the photo with the rail surface fatigue damage rating atlas comprises determining that, when the characteristics and damage density of the rail surface damage in the photo are close to an n-grade rail surface fatigue damage standard atlas in the rail surface fatigue damage rating atlas, the rail surface fatigue damage degree of the rail to be evaluated is n grade; and when the characteristics and damage density of the rail surface damage in the photo are between the n-grade rail surface fatigue damage standard atlas and an n+1-grade rail surface fatigue damage standard atlas, the rail surface fatigue damage degree of the rail to be evaluated is n.5 grade, wherein n is 0-7.

4. The rating map-based rail head fatigue damage level evaluation method of claim 1, wherein, the resolution of the photo is not less than 1080p.

5. The rating map based rail head fatigue damage assessment method of claim 1 wherein, the photo should cover at least 0.5 meters of the rail.

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