Railway carriage inspection method

Abstract

To provide an inspection method of a railway vehicle which can improve inspection efficiency while assuring an inspection accuracy during a periodic inspection regarding a fatigue damage.SOLUTION: This inspection method is an inspection method of plural railway trucks each of which have truck frames. The plural trucks have the same dimensional shapes and are used on the same tracks. The inspection method has a set process (#10), a use process (#20) and an inspection process (#30). In the set process (#10), plural railway trucks are allocated to either a first truck or a second truck. The truck frame of the first truck is a first truck frame which is relatively weak in fatigue strength and the truck frame of the second truck is a second truck frame which is relatively weak in a fatigue strength. In the inspection step (#30), the first truck and the second truck both used on the track are periodically inspected. In the inspection step (#30), a whole area of the first truck frame is subjected to a nondestructive test and about the second truck frame, important inspection points in the design aspect are subjected to nondestructive tests.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a method for inspecting a railway carriage (hereinafter also simply referred to as a "carriage").

Background Art

[0002] Normally, a large number of trains operate on a single railway line. Usually, a train is composed of a plurality of vehicles, and each vehicle is equipped with two carriages. That is, on a single line, for example, a large number of more than 100 carriages are repeatedly used. In order to maintain the safe running of the train, regular inspection of the carriages is essential. During regular inspection, non-destructive inspection is performed to check for fatigue damage of the carriages. The area occupied by the carriage frame in the carriage is large. Therefore, it requires a great deal of labor to perform non-destructive inspection on the entire surface of each carriage frame.

[0003] For example, Japanese Patent Application Laid-Open No. 2005-164247 (Patent Document 1) discloses a technique related to a fatigue sensor. The fatigue sensor disclosed in Patent Document 1 is in the form of a foil and has a size of several millimeters square. Patent Document 1 suggests that by attaching the fatigue sensor to the carriage frame, it is possible to detect fatigue damage of the carriage frame during the use of the railway carriage.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The fatigue sensor can detect fatigue damage occurring in a specific direction. However, various loads act on the bogie frame in a complex manner. Therefore, in the bogie frame, the positions and directions where fatigue accumulates are uncertain. Furthermore, it is also uncertain what kind of fatigue damage will occur. Then, it is difficult to specify the positions and directions for attaching the fatigue sensor. In this case, it cannot be said that fatigue damage can be accurately detected only by the fatigue sensor. Therefore, in the technology described in Patent Document 1, it is still necessary to perform non-destructive inspection on each bogie frame over the entire surface during regular inspections.

[0006] An object of the present disclosure is to provide an inspection method for railway vehicles that can improve inspection efficiency while ensuring inspection accuracy during regular inspections regarding fatigue damage.

Means for Solving the Problem

[0007] The inspection method for railway vehicles according to the present disclosure is an inspection method for a plurality of railway vehicles each having a bogie frame. The plurality of railway vehicles have the same dimensional shape and are used on the same route. The inspection method includes a setting step, a use step, and an inspection step. In the setting step, the plurality of railway vehicles are assigned to either a first vehicle or a second vehicle. The bogie frame of the first vehicle is a first bogie frame that is relatively inferior in fatigue strength, and the bogie frame of the second vehicle is a second bogie frame that is relatively superior in fatigue strength. In the use step, the first vehicle and the second vehicle are used on the route. In the inspection step, the first vehicle and the second vehicle are regularly inspected. In the inspection step, the entire surface of the first bogie frame is non-destructively inspected, and the design-critical inspection points of the second bogie frame are non-destructively inspected.

Effect of the Invention

[0008] According to the inspection method for railway vehicles according to the present disclosure, regarding fatigue damage, inspection efficiency can be improved while ensuring inspection accuracy during regular inspections.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Embodiments for Carrying out the Invention

[0010] Hereinafter, embodiments of the present disclosure will be described. In the following description, embodiments of the present disclosure will be described with examples, but the present disclosure is not limited to the examples described below. In the following description, specific numerical values and specific materials may be exemplified, but the present disclosure is not limited to those examples.

[0011] The inspection method for a railway carriage according to the present embodiment is an inspection method for a plurality of railway carriages each having a carriage frame. The plurality of railway carriages have the same dimensional shape and are used on the same route. The inspection method includes a setting step, a use step, and an inspection step. In the setting step, the plurality of railway carriages are assigned to either a first carriage or a second carriage. The carriage frame included in the first carriage is a first carriage frame that is relatively inferior in fatigue strength, and the carriage frame included in the second carriage is a second carriage frame that is relatively superior in fatigue strength. In the use step, the first carriage and the second carriage are used on the route. In the inspection step, the first carriage and the second carriage are inspected regularly. In the inspection step, the entire surface of the first carriage frame is nondestructively inspected, and the important inspection points in terms of design of the second carriage frame are nondestructively inspected (the first configuration).

[0012] In the inspection method of the first configuration, the plurality of bogies are composed of a first bogie and a second bogie, have the same dimensional shape, and are used on the same route. That is, the first bogie and the second bogie are used under the same conditions. In this case, the tendency regarding fatigue damage is consistent between the first bogie and the second bogie. However, the first bogie frame of the first bogie is relatively inferior in fatigue strength, and the second bogie frame of the second bogie is relatively excellent in fatigue strength. That is, the fatigue strength of the first bogie frame is lower than that of the second bogie frame. In this case, fatigue damage will occur in the first bogie frame at an earlier time than in the second bogie frame. Then, if the first bogie frame is intensively non-destructively inspected in the inspection process of regular inspection, the quality of the second bogie frame can be guaranteed by the inspection result of the first bogie frame. In this specification, the entire surface of the bogie frame (the first bogie frame and the second bogie frame) may or may not include appendages (e.g., bogie suspension fittings) that are irrelevant to running.

[0013] Therefore, if a part such as an important inspection point in design is non-destructively inspected for the second bogie frame, the inspection accuracy of all the plurality of railway bogies can be ensured. In this case, the non-destructive inspection of the second bogie frame is sufficient with a part rather than the whole. For this reason, the inspection efficiency can be improved.

[0014] The number of the first bogies among the plurality of bogies, that is, the number of the first bogie frames, may be at least one. Since the non-destructive inspection of the first bogie frame needs to be performed on the whole, the fewer the number of the first bogie frames, the higher the inspection efficiency can be.

[0015] In a typical example, in one train, the number of the first bogie frames is one, and the remaining bogie frames other than the first bogie frame are second bogie frames. In one train, the number of the first bogie frames may be two or more. Also, in a plurality of trains, the number of the first bogie frames may be one. That is, as long as one of the plurality of trains has a first bogie frame, there may be a train that has only a second bogie frame without a first bogie frame.

[0016] In the inspection method of the first configuration, preferably, the first bogie frame is a bogie frame plated in the setting process (second configuration). The fatigue strength of the plated bogie frame is lower than that of the non-plated bogie frame. Therefore, if the bogie frame is plated, the first bogie frame can be manufactured. In this case, if no surface treatment other than the design specification is applied to the bogie frame, that bogie frame can be directly treated as the second bogie frame. Here, according to the design specification, the bogie frame is not plated.

[0017] From the perspective of improving inspection efficiency, as described above, the fewer the number of the first bogie frames, the better. In the case of the second configuration, if the number of the first bogie frames is small, the man-hours for surface treatment (plating) in the setting process can be reduced, and the setting process becomes simpler. Therefore, the inspection method of the second configuration is useful in that the working efficiency of the setting process is high.

[0018] In the inspection method of the first configuration, the second bogie frame may be a bogie frame subjected to shot peening or thermal spraying in the setting process (third configuration). The fatigue strength of the bogie frame subjected to shot peening is higher than that of the bogie frame not subjected to shot peening. Therefore, if shot peening is applied to the bogie frame, the second bogie frame can be manufactured. In this case, if no surface treatment other than the design specification is applied to the bogie frame, that bogie frame can be directly treated as the first bogie frame. The same applies to the case of thermal spraying as in the case of shot peening. Here, according to the design specification, neither shot peening nor thermal spraying is applied to the bogie frame.

[0019] From the perspective of improving inspection efficiency, as described above, the fewer the number of the first bogie frames, the better. In this regard, in the case of the third configuration, if the number of the first bogie frames is small, the number of the second bogie frames increases, and the man-hours for surface treatment (shot peening or thermal spraying) in the setting process increase. Therefore, it is undeniable that the setting process becomes complicated. However, the fatigue strength of neither bogie frame (the first bogie frame and the second bogie frame) decreases. Therefore, the inspection method of the third configuration is useful in that it has high safety.

[0020] In any one of the inspection methods from the first configuration to the third configuration, preferably, in the setting process, a strain sensor is attached to the first bogie frame, and in the usage process, the state of the first bogie frame is monitored based on the detected value of the strain sensor (fourth configuration). In the case of the inspection method of the fourth configuration, even if an abnormality occurs in the first bogie frame, which is relatively inferior in fatigue strength, during the usage process, the abnormality can be detected. Thereby, the reliability of the first bogie frame in the usage process can be guaranteed, and as a result, the reliability of all bogie frames in the usage process can be ensured.

[0021] Hereinafter, a specific example of the inspection method for a railway vehicle according to the present embodiment will be described with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals and their description will not be repeated.

[0022] [First Embodiment] FIG. 1 is a flowchart showing the inspection method for a railway vehicle according to the present embodiment. Referring to FIG. 1, the inspection method of the present embodiment generally includes a setting process (#10), a usage process (#20), and an inspection process (#30). The flowchart of the inspection method of the present embodiment shown in FIG. 1 is common to each of the embodiments described later.

[0023] FIG. 2 is a schematic diagram showing an example of the application conditions of the inspection method according to the present embodiment. The inspection method of the present embodiment is an inspection method for a plurality of railway vehicles 1. Each of these vehicles 1 includes a bogie frame 2. Each vehicle 1 further includes an axle, wheels, axle boxes, a gear device, an electric motor (e.g., an electric motor), a traction device, a bolster, and a vehicle body support spring (e.g., an air spring), etc. Each vehicle 1 has the same dimensional shape and is manufactured with the same design specifications.

[0024] The bogies 1 are arranged at the front and rear of the car body 3, respectively. That is, one vehicle 4 is composed of one car body 3 and two bogies 1. A plurality of vehicles 4 are connected to form one train 5. The train 5 repeatedly runs on the same route L between terminal stations. Also, a plurality of trains 5 configured in the same way repeatedly run on the same route L. In this case, each bogie 1 is used on the same route L. Therefore, each bogie 1 is used under the same conditions. In the example shown in FIG. 2, the train 5 includes six bogies 1.

[0025] Referring to FIGS. 1 and 2, the inspection method of this embodiment will be continued. As described above, the inspection method of this embodiment includes a setting step (#10), a use step (#20), and an inspection step (#30). In the inspection method of this embodiment, the setting step (#10) is performed before the train 5 actually runs on the route L, that is, before each bogie 1 is used. That is, after the setting step (#10), the use step (#20) is performed. Then, after the use step (#20), the inspection step (#30) is performed as a regular inspection.

[0026] In the setting step (#10), a plurality of bogies 1 are assigned to either the first bogie 11 or the second bogie 12. In the example shown in FIG. 2, six bogies 1 are assigned to one first bogie 11 and five second bogies 12. The bogie frame 2 of the first bogie 11 has a fatigue strength different from that of the bogie frame 2 of the second bogie 12. The bogie frame 2 of the first bogie 11 is the first bogie frame 21, and the fatigue strength of the first bogie frame 21 is relatively low. The bogie frame 2 of the second bogie 12 is the second bogie frame 22, and the fatigue strength of the second bogie frame 22 is relatively high. That is, the fatigue strength of the first bogie frame 21 is lower than that of the second bogie frame 22. The number of the first bogie frames 21 is one, and the number of the second bogie frames 22 is five.

[0027] The first bogie frame 21 is the bogie frame 2 with plating. The second bogie frame 22 is the bogie frame 2 without plating. Here, according to the design specifications, the bogie frame 2 is not plated. Therefore, the second bogie frame 22 is the bogie frame 2 as per the design specifications without any surface treatment other than the design specifications. The fatigue strength of the plated bogie frame 2 (the first bogie frame 21) is lower compared to the fatigue strength of the non-plated bogie frame 2 (the second bogie frame 22). In this case, the amount of reduction in fatigue strength is about 30%.

[0028] Next, in the usage process (#20), a train 5 including the first bogie 11 (the first bogie frame 21) and the second bogie 12 (the second bogie frame 22) is run on the line L. In this case, the first bogie 11 and the second bogie 12 are used on the same line L. For this reason, the first bogie 11 and the second bogie 12 are used under the same conditions. The use of such first bogie 11 and second bogie 12 is repeated until the time for regular inspection arrives.

[0029] In the inspection process (#30), the first bogie 11 and the second bogie 12 are regularly inspected. At this time, the entire surface of the first bogie frame 21 is non-destructively inspected. On the other hand, for the second bogie frame 22, the non-destructive inspection is carried out on the important inspection points determined by the design. The key inspection points are defined in the design specifications.

[0030] The method of non-destructive inspection is not particularly limited. As the method of non-destructive inspection, well-known methods used in the regular inspection of railway bogies can be applied. For example, as the method of non-destructive inspection, visual inspection, ultrasonic flaw detection test, eddy current flaw detection test, magnetic particle flaw detection test, and penetrant flaw detection test, etc. can be applied.

[0031] In addition, in the inspection process (#30), together with the non-destructive inspection of the first bogie frame 21 and the second bogie frame 22 respectively, the inspection of each element (axle, wheel, axle box, gear device, motor, traction device, bolster, and spring for car body support, etc.) that constitutes the first bogie 11 and the second bogie 12 is also carried out.

[0032] [Effect] In the inspection method of this embodiment, in the usage process (#20), the first bogie 11 and the second bogie 12 are used under the same conditions. In this case, the tendencies regarding fatigue damage are the same between the first bogie 11 and the second bogie 12. That is, between the first bogie frame 21 and the second bogie frame 22, the positions and directions where fatigue accumulates are the same, and the positions where fatigue damage occurs are the same. However, the fatigue strength of the first bogie frame 21 is lower than that of the second bogie frame 22. In this case, fatigue damage will occur in the first bogie frame 21 at an earlier time than in the second bogie frame 22. Then, if the first bogie frame 21 is intensively nondestructively inspected over the entire surface in the inspection process (#20) of regular inspection, the quality of the second bogie frame 22 can be guaranteed by the inspection result of the first bogie frame 21.

[0033] Therefore, if a part such as an important inspection point in terms of design of the second bogie frame 22 is nondestructively inspected, the inspection accuracy of all the plurality of railway bogies 1 can be ensured. In this case, the nondestructive inspection of the second bogie frame 22 suffices with a part rather than the entire surface. For example, when no fatigue damage is confirmed in the nondestructive inspection of the first bogie frame 21, it is sufficient to perform the nondestructive inspection of the second bogie frame 22 only at the important inspection points. If fatigue damage is confirmed in the nondestructive inspection of the first bogie frame 21, the nondestructive inspection of the second bogie frame 22 suffices if it is performed at the important inspection points and at the position where the fatigue damage of the first bogie frame 21 was confirmed. For this reason, the inspection efficiency can be improved. In short, regarding fatigue damage, it is possible to improve the inspection efficiency while ensuring the inspection accuracy at the time of regular inspection.

[0034] In this embodiment, in one train 5, the number of the first bogie frames 21 is one, and the number of the second bogie frames 22 is five. The number of the first bogie frames 21 only needs to be at least one. Since the nondestructive inspection of the first bogie frame 21 needs to be performed over the entire surface, the fewer the number of the first bogie frames 21, the higher the inspection efficiency can be. In other words, the more the number of the second bogie frames 22 is relatively, the higher the inspection efficiency can be.

[0035] From the perspective of improving inspection efficiency, as described above, the fewer the number of the first car body frames 21, the better. If the number of the first car body frames 21 is small, the man-hours for surface treatment (plating) in the setting process (#10) can be reduced. The second car body frames 22 with a large number are not subjected to surface treatment. For this reason, the setting process (#10) is simplified, and the working efficiency of the setting process (#10) is high.

[0036] [Second Embodiment] The inspection method of the second embodiment is a modification of the setting process (#10) in the above-described first embodiment. Hereinafter, with reference to FIGS. 1 and 2 above, the inspection method of this embodiment will be described.

[0037] In the setting process (#10), the second car body frame 22 is the car body frame 2 that has been shot-peened. The first car body frame 21 is the car body frame 2 that has not been shot-peened. Here, in the design specification, neither shot peening nor thermal spraying is performed on the car body frame 2. Therefore, the first car body frame 21 is the car body frame 2 in the design specification without any surface treatment other than the design specification. The fatigue strength of the car body frame 2 (second car body frame 22) that has been shot-peened increases as compared with the fatigue strength of the car body frame 2 (first car body frame 21) that has not been shot-peened. That is, similar to the first embodiment described above, the fatigue strength of the first car body frame 21 is lower than the fatigue strength of the second car body frame 22.

[0038] Furthermore, the usage process (#20) and the inspection process (#30) are the same as those in the first embodiment described above. Therefore, similar to the first embodiment described above, regarding fatigue damage, during regular inspections, it is possible to improve the inspection efficiency while ensuring the inspection accuracy.

[0039] Also, similar to the first embodiment, from the perspective of improving inspection efficiency, it is better if the number of the first bogie frames 21 is smaller. In this regard, in the case of this embodiment, if the number of the first bogie frames 21 is small, the man-hour for surface treatment (shot peening) in the setting process (#10) will increase. This is because the number of the second bogie frames 22 will increase. Then, it is undeniable that the setting process (#10) will become complicated. However, the fatigue strength of any of the bogie frames 2 (the first bogie frame 21 and the second bogie frame 22) will not decrease. Therefore, the safety is high.

[0040] In this embodiment, spraying can be adopted instead of shot peening. This is because, similar to the case of shot peening, the fatigue strength of the sprayed bogie frame 2 (the second bogie frame 22) will increase compared to the fatigue strength of the unsprayed bogie frame 2 (the first bogie frame 21).

[0041] [Third Embodiment] The inspection method of the third embodiment is a modification of the setting process (#10) and the use process (#20) in the above-described first embodiment. Hereinafter, with reference to FIGS. 1 and 2 above, the inspection method of this embodiment will be described.

[0042] In the setting process (#10), further, a strain sensor (not shown) is attached to the first bogie frame 21. The attachment position and number of the strain sensors are not particularly limited. However, the strain sensors are preferably attached to the parts where stress is likely to concentrate in terms of design (e.g., key inspection points). On the other hand, it is not necessary to attach a strain sensor to the second bogie frame 22.

[0043] In the use process (#20), the state of the first bogie frame 21 is monitored based on the detected values of the strain sensors. Specifically, during the running of the train 5, the detected values from the strain sensors are transmitted to the railway line management center, and the management center monitors the fluctuations of the detected values. Thereby, the state of the first bogie frame 21 can be monitored.

[0044] In this embodiment, similar to the above-described first embodiment, the fatigue strength of the first bogie frame 21 is relatively inferior. For this reason, the reliability of the first bogie frame 21 may be a concern. However, in the usage process (#20), even if an abnormality occurs in the first bogie frame 21 by chance, the abnormality can be detected. Thereby, the reliability of the first bogie frame 21 in the usage process (#20) can be guaranteed, and as a result, the reliability of all the bogie frames 2 in the usage process (#20) can be ensured.

[0045] Note that the inspection method of this embodiment may be applied to the second embodiment.

Explanation of Reference Numerals

[0046] 1: Bogie 11: First Bogie 12: Second Bogie 2: Bogie Frame 21: First Bogie Frame 22: Second Bogie Frame 3: Car Body 4: Vehicle 5: Train L: Track

Claims

1. A method for inspecting a plurality of railway cars, each having a car body frame, having the same dimensional shape, and used on the same track, comprising: a setting step of assigning the plurality of railway cars to either a first car or a second car, wherein the car body frame of the first car is a first car body frame that is relatively inferior in fatigue strength, and the car body frame of the second car is a second car body frame that is relatively superior in fatigue strength; the setting step; a using step of using the first car and the second car on the track; an inspection step of periodically inspecting the first car and the second car, wherein the entire surface of the first car body frame is non-destructively inspected, and important inspection points in terms of design of the second car body frame are non-destructively inspected; the inspection step. A method for inspecting railway cars.

2. The method for inspecting railway cars according to claim 1, wherein the first car body frame is the car body frame that has been plated in the setting step. A method for inspecting railway cars.

3. The method for inspecting railway cars according to claim 1, wherein the second car body frame is the car body frame that has been shot peened or thermal sprayed in the setting step. A method for inspecting railway cars.

4. The method for inspecting railway cars according to any one of claims 1 to 3, wherein in the setting step, a strain sensor is attached to the first car body frame, and in the using step, the state of the first car body frame is monitored based on the detected value of the strain sensor. A method for inspecting railway cars.

Images