WO2014027977A1

WO2014027977A1 - A method for the detection of rail fractures and cracks

Info

Publication number: WO2014027977A1
Application number: PCT/TR2013/000262
Authority: WO
Inventors: Sabri Haluk GOKMEN
Original assignee: ENEKOM ENERJI EKOLOJI BILIŞIM VE MUHENDISLIK SANAYI TICARET LIMITED ŞlRKETI
Priority date: 2012-08-14
Filing date: 2013-08-14
Publication date: 2014-02-20

Abstract

The invention particularly relates to a method of detection of rail cracks or fractures that can be used for the determination of rail breakdowns in the field of railway systems technology and incorporates a power supply (800), an electromechanical vibration application module (100) that periodically applies a vibration signal to the rail (200) body with the energy taken from the said power supply (800), a vibration application module drive card (120) which drives this module and a vibration sensing module (600) that is oriented on the same rail at a certain distance from the electromechanical vibration application module (100), and an electronic sensing card for vibration sensing module (620) with a capability to communicate to the outside world with various means and process the incoming signal, evaluating it for the detection of rail cracks and fractures, a vibration sensor (626).

Description

DESCRIPTION

A METHOD FOR THE DETECTION OF RAIL FRACTURES AND CRACKS THE RELATED ART

The invention relates to a detection method that can be used for finding the defects in rails, such as cracks or fractures, used in railway systems technology.

The invention particularly relates to a power supply, an electro-mechanical vibration application module that periodically hits the rail body with the energy taken from said power supply, and vibrates the rail, a system consisting of vibration detection and signal processing module that at a certain distance from the application module, that orients in the same rail, and a railway fracture or crack detection method which can be utilized for the determination of the railway track defects, used in the railway systems technology.

THE PRIOR ART

The railway systems are becoming more crucial in the world because they are fast, economical, environment-friendly, and highly secure modern transportation systems. One of the most significant features of the railway systems is that they are public service vehicles which have substantial security measures. The sustainability of this feature, of course, can be achieved with regular maintenanceefforts to these systems. The measurement of track deformation and detection of the cracks and fractures in the rail take an important place within these maintenance efforts. The deformations in the railway systems occur mostly due to the wear out of wheel flange which are corroded and lost their normal shapes, the huge forces that affect the outer rail because of the effective centrifugal forces in the bends, the overspeeding trains and the rails that are not at the same height level, the dilatation because of the climate change and lots of other reasons. Due to the chemical nature of the rails, they are effected by water, moisture and the soil, and as a result, corrosion, incrustation, and similar oxidation processes become effective on the rail surface and cause to serious

l deformations on rails. When it is the case, determination of these deformations and all other factors trfat become a threat to the security of the railway operation, become crucial.

In the prior art, mostly, the railway track is divided into specific length zones and the track circuits that detect the presence of the train are used in these areas. Although, the track circuit zone length depends on the ballast resistance, they usually control around 1 Km long railway track. As the train enters into this zone, it is detected by the track circuit and this information is transferred to the signaling system. The track circuits are also used for detecting the rail cracks. However, the rails are also used as an electrical return line for the catenary power and this causes to misleading or untrustworthy rail crack readings.

In the prior art, usually the railway controllers are acting a part to determination of the rail crack and fractures. These officials are controlling the rail for miles step by step, visually or with basic hand measuring tools. All over the world, millions of kilometers of railway line and necessary labor force to try to meet this task is enough to prove that this method is very impractical. Some major railway accidents have happened and many casualties were given because of these kind of difficult or even impossible to detect rail deformations, fractures or cracks, lately.

Another method used in the prior art is the using of ultrasonic or static test devices. For instance, an ultrasonic signal is applied to a point of the rail from a source and the reflected sound wave is processed in order to find the gaps, if any, in the rail. With these ultrasonic devices merely a point analysis can be done. These devices are put into a maintenance train and this train makes a measuring tour at a 5-10 km an hour speed in the middle of the night, when the line is less intense or generally empty. It measures the track as far as possible and report the necessary data to the maintenance/repair team. It is a very heavy and costly method.

Another method used in the prior art is the systems determining the rail cracks and deformations with the help of an electronic camera, some sensors and a computer attached to them. In these systems the cracks and deformations can be determined by means of the special cameras and sensors that can be put under any wagon or railcar moving on the track, in order to observe the rail, and a computer system with some software connected to them. This method consists of very expensive technological items and also the fact that the devices are always exposed to extreme external factors which cause to the destruction of these devices early and prevent the system to make accurate measurements always. In addition, the information about the rail crack and fractures or deformations cannot be retrieved sufficiently all the time, but only after the use of the track by a measuring train, the most current detection data can be obtained.

Another method is the determination of the rail crack and deformation by photography method. Electronic sensors and GPS navigation system are connected to the bottom of a train wagon or a similar railway vehicle and as this railway vehicle passes through the cracked or deformed rail, sensors determine the deformation and alert to GPS navigation system at the same time, and the navigation system informs computer about the location of this deformed rail segment. There are many methods that can be used in the prior art. The main ones are; laser, sensitive sensors, high resolution and fast shooting cameras. The common problem of these kind of systems is the necessity to adapt a train or a railway vehicle which has at least specially equipped two wagons , moving on the track frequently, in order to detect cracks, fractures or deformations on the rail. Since the cracks, fractures or deformations usually occur after the train crossings, establishment of this kind of a convoy and hit the line for necessary measurements, sometimes may not cause to any contribution to the detection of the problem and cause to severe accidents.

As a result of the preliminary research on the current technic, the patent files CN201971030 (U) and CN201721463 (U) were investigated. With this method, the integration of the line is measured only electrically. Although this method is still used, especially since the rail is used as the return current flow path of the railway catenary system, usually gives wrong or deceptive information and also because of its high cost it is not as useful.

Another patent encountered after the preliminary research is the patent numbered US5743495 (A). This patent deals with the detection of the vibrations originating from the railway vehicle traveling on the rail, with the help of the sensors and evaluation of this gathered signal. These kind of systems are passive systems and a railway vehicle is expected to pass through the deformed rail segment for measurements. When the railway vehicle passing through the rail it can be too late to avoid an accident and in some situations derailments may occur. Therefore, this kind of systems cannot be a reliable solution to the existing rail problems.

Another patent found in another investigation on the prior art is a Japanese patent numbered JP2002131042 (A). In this patent, the vibrations and sounds created by railway vehicle's wheels on the rail picked up with the help of the sensors and the deformed area on the rail is tried to be defined. However, this system reveals the same negative results as the previous American patent.

Another patent found in this investigation is a German patent numbered DE19858937. When this patent is examined, it can be seen that the patent mentions about a method with the sensors attached on to the rails and vibrations created by the passing by railway vehicle is picked up by these sensors and processed and the railway vehicle is informed about the status of the rails accordingly. All these systems and methods always require a railway vehicle to generate the vibrations on the rails. Namely, detection and notification of the deformations on the rails cannot be achieved before the railway vehicle passes.

Another patent encountered after the preliminary research is an American patent numbered US6216985 (B1). This patent again needs a railway vehicle. It includes a system similar to the previous patents mentioned and its inadequacies, as mentioned before, constrain its usage.

Consequently, it is now necessary to develop a new rail crack or fracture detection system in which the detection method is more secure and have various advantages compared to other existing similar systems. PURPOSE OF THE INVENTION

The invention solves all the problem mentioned above, at once. The most general form of the present invention is a power supply, an electro-mechanical vibration application module that periodically vibrates the rail body with the energy taken from said power supply, and a system consisting of vibration detection, signal processing, decision making module, which is located at a certain distance from the application module, that is attached on to the same rail, and a communication module which is connecting both sides and a rail fracture or crack detection method which can be used for determination of the rail faults in the field of railway systems technology. The most significant purpose of the invention is the capability to determine the visible or invisible fractures, cracks or deformations on the railway line just after any one of these problems occur, and without the need for any a railway vehicle to pass. Since the line is divided into specific detection zones according to the method, the location of the breakdown can be easily determined by these zones. Besides that, when performing this detection operation, no railway vehicles are needed, and thus any cracks, fractures and deformations on the rails can be pre-detected. So it becomes possible to prevent major railway accidences that may occur due these kind of reasons.

Another purpose of the invention is the elimination of the inadequacies of the point based analysis performed by the ultrasonic fracture and crack detection equipment, and detection of fractures and cracks much easily and quickly on a long railway line, at once. On the other hand, our system can easily overcome the problems created by the use of ultrasonic systems such as the data in regards to the detection of fractures and cracks from all over the line could not be collected at any moment since it works with point principle. Usually the cracks or fractures on the rail start when the railway vehicle moves on the track and then they become apparent or otherwise, they occur when the track is exposed to extreme temperature conditions. Hence, the continuous gathering and evaluation of data from the track in regards to the rail fractures and cracks is a crucial discrepancy. Consequently, it is necessary to-prevent the possible accidents by detecting the rail fractures and cracks without a need to expect the line unoccupied by any railway vehicle but at the same time instantly and accurately.

Another purpose of the invention is to detect not only the visible cracks or deformations on the surface layer of the rail body by electronic and camera sensors as used in the prior art, but also to detect the cracks which may occur anywhere on the rail body.

Another purpose of the invention to make a rail fracture and crack detector which is less costly than the laser, sensitive sensors or high-resolution and fast shooting cameras and similar detection systems, and to eliminate the disadvantages of these systems, with its simpler structure.

Another purpose of the invention is, by means of this system, the fractures and cracks on the high-speed railway tracks in particular, and all the railway lines in broad terms, can be detected just at the beginning stage or just after the formation of the fault, and necessary warning signals can be generated before the railway vehicle reaches to the troubled area. In line with the mentioned purposes, the invention eliminating the problems in the currently available systems, in the field of railway systems technology, used for the detection of the rail failures contains these operational steps:

- Applying vibrations to the rail body from a signal point of entry with the energy taken from the power supply, with the help of the electro-mechanical vibration application module,

Driving the electro-mechanical vibration application module with the driving board that works with synchronous or asynchronous data transmitted via a communication line extending alongside the trackside,

- Detecting the vibrations on the rail, applied at the signal point of entry, by a vibration detecting module at a certain distance from the point of entry, on the same rail. Assuming the duty of evaluating the signal coming from the vibration detecting module by the vibration detecting electronic control board that works synchronously or asynchronously with the data transmitted via a communication line extending alongside the track, and concluding definitely that whether the rail has a crack or fracture.. i. Mentioned electromechanical vibration application module is; driven by the driver interface module of vibration application module drive card of vibration application module drive card, consisting of the driver interface of vibration application module drive card which is controlled and directed by the microprocessor of vibration application module drive card, consisting of the microprocessor for the vibration application module's drive card which helps to keep all the data gathered during the operations in the drive board's memory,

capable of processing data, by the help of the microprocessor of vibration application module drive card, coming through the serial communication interface circuit of the vibration application module's drive card which is connected to the wired or wireless communication interface circuit,

capable of sending the processed data, by the help of the microprocessor of vibration application module drive card, through to the serial communication interface circuit of the vibration application module's drive card which is connected to the wired or wireless communication interface circuit, ii. mentioned vibration sensing module consists of; the vibration sensing module interface, to transfer the vibration signal coming from the rail into the electronic sensing card of vibration sensing module, - the vibration sensor, for the conversion of mechanical vibration which is carried into the electronic sensing card of vibration sensing module via the vibration sensing module interface into an electrical signal.

- the vibration sensing interface circuit which accepts the electrical signal generated by the vibration sensor and transfers this signal into the vibration signal processing unit,

- the vibration signal processing unit converts this electrical analog vibration signal into the digital format and transfers it into the microprocessor of vibration sensing module's electronic sensing card, ,

- the microprocessor of the vibration sensing module's electronic sensing card identifies the digital vibration signal which is taken from the rails by making a series of mathematical operations on it and transfers this concluded rail crack or fracture information to the external memory or PC connection module through to the serial communication port of vibration sensing module's electronic sensing card or to the memory of the vibration sensing module's electronic sensing card and also to the communication line which extends alongside the railway track through to the serial

I/O port, to vibration sensing module's electronic sensing card which is connected to the wired or wireless communication system interface.

The invention in its present form and simple structure, will be a preferred product in the sector. Thus provide a commercial success. Structural and characteristic features and all advantages of the invention will be understood more clearly with help of the following figures and detailed description written in reference to these figures. Therefore, this evaluation should be made by considering the drawings and related detailed description.

FIGURES FOR BETTER UNDERSTANDING OF THE INVENTION Figure -1 ; the drawing that shows the electro mechanical vibration application module within the rail crack or fracture detection method of the invention.

Figure-2; the drawing that shows the vibration detection module within the present rail crack or fracture detection method of the invention. Figure-3; the drawing that shows the transmission of the vibration through the rails in the line from the point that is applied to the line, to the point that is detected, within the present rail crack or fracture detection method of this invention.

Figure -4; the drawing that shows the electronic principle diagram of the electronic sensing card for vibration detection module of this invention. Figure-5; the drawing that shows the electronic principle diagram of the electromechanical vibration application module within the present rail crack or fracture detection system of this invention.

REFERENCE NUMBERS

100. Electromechanical Vibration Application Module 110. Vibration Application Module Mechanical Interface

120. Vibration Application Module Drive Card

121. Driver Interface of Electromechanical Vibration Application Module's Drive Circuit

122. Microprocessor of Vibration Application Module's Drive Card

123. Memory of Vibration Application Module's Drive Card 124. Serial Communication Interface Circuit of Vibration Application Module's Drive Card 125. Wired or Wireless Communication Interface Circuit

200. Raif

300. Vibration Signal Application Point

400. Communication Line

500. Vibration Signal Sensing Point

600. Vibration Sensing Module

610. Vibration Sensing Module Interface

620. Electronic Sensing Card for Vibration Sensing Module

621. Vibration Sensing Interface Circuit

622. Microprocessor of Vibration Sensing Module's Electronic Sensing Card

623. Serial Communication Port of Vibration Sensing Module's Electronic Sensing Card

624. Serial Communication I/O Port of Vibration Sensing Module's Electronic Sensing Card

625. Memory of Vibration Sensing Module's Electronic Sensing Card

626. Vibration Sensor

627. Vibration Signal Processing Unit

628. Wired or Wireless Communication System Interface

700. External Memory or PC Connection Module

800. Power Supply The invention will be better understood with the given detailed description below made with the given reference numbers above and attached figures.

DETAILED DESCRIPTION OF THE INVENTION

Here, the present invention comprises; electro mechanical vibration application module (100), vibration application module drive card (120), on this board; driver interface of vibration application module drive card (121 ), on the electromechanical vibration application module (100); microprocessor of vibration application module drive card (122), serial communication interface circuit of vibration application module drive card (124), wired or wireless communication system interface circuit (125), memory of vibration application module drive card (123), vibration application module mechanical interface (1 10), the rail (200), vibration signal application point (300), communication line (400), vibration signal sensing point (500), vibration sensing module (600), vibration sensing module interface (610), electronic sensing card for vibration sensing module (620) and on this board; vibration sensing interface circuit (621 ), microprocessor of vibration sensing module's electronic sensing card (622), serial communication port of vibration sensing module's electronic sensing card (623), serial commucation I/O port of vibration sensing module's electronic sensing card (624), memory of vibration sensing module's electronic sensing card (625), vibration sensor (626), vibration signal processing unit (627), wired or wireless communication system interface (628), external memory or PC connection module (700), and power supply (800).

The invention in general terms, consists of a power supply which provides the required energy for the system (800), an electromechanical vibration application module (100) which applies vibration signal to the rail (200) body at certain intervals with the energy taken from the system's power supply (800); a vibration application module drive card (120) which drives the module; a vibration sensing module (600) which is coupled on to the vibration applied rail (200) body, and an electronic sensing card for vibration sensing module (620) which processes the signal coming into this module electrically. Our system works on the principle of sensing the mechanical vibration based signal applied to the rail (200) from a further point, sensing and processing this signal at a distance and coming to a clear conclusion about if there is any crack or fracture on the rail (200).

As shown in Figure-1 , a mechanical vibration based signal is applied from a specific point on the rail (200) extending along the communication line (400) with the help of the electromechanical vibration application module (100). The electromechanical vibration application module (100) takes on the task of converting the electrical signal that is generated in the system into the mechanical form and applying it to the rail (200). The energy needed for the electromechanical vibration application module (100) to work is provided by an external power supply (800). The vibration signal, which is applied to the rail (200) by the vibration application module mechanical interface (110) on the electromechanical vibration application module (100) is, as shown in Figure-3, applied onto the rail (200) from the vibration signal application point (300) and transmitted to the vibration signal sensing point (500) at a certain distance on the rail (200) which is extending along the communication line (400) depending on the strength of the signal and physical conditions of the rail (200).

The mentioned electromechanical vibration application module (100), as shown in Rgure-5, operates as follows:

- The electromechanical vibration application module (100) is driven by the driver interface of the vibration application module's drive card (121) on the vibration application module's drive card (120). - The driver interface of the vibration application module's drive card (121) is controlled and directed by the microprocessor (122) of the vibration application module's drive card (120).

- The microprocessor of vibration application module's drive card (122) keeps all the data gathered during the process in the memory of vibration application module driving board system memory (123).

- The microprocessor of the vibration application module's drive board (122) evaluates the data coming from the external communication line (400) via the serial communication interface circuit of vibration application module's drive card (124) and wired or wireless communication interface circuit (125) during the driving process of the electromechanical vibration application module (100).

- The microprocessor of the vibration application module's drive board (122) relay all the necessary information about the process to the external communication line (400) by using the serial communication interface circuit of vibration application module drive card (124) and wired or wireless communication interface circuit (125) during the driving process of the electromechanical vibration application module (100).

The signal that reached to the vibration signal sensing point (500) is taken by the vibration sensing module interface (610) in the vibration sensing module (600) as shown in Figure-2, and transmitted to the electronic sensing card for vibration sensing module (620) as shown in Figure-4. Firstly, the vibration signal that is picked up by the vibration sensor (626) in the electronic sensing card for vibration sensing module (620) is passed through the vibration sensing interface circuit (621) and converted into the electrical signal for the vibration signal processing unit (627) to process the signal. Afterwards, this electrical analog signal is converted into the digital format in the vibration signal processing unit (627) and transmitted to the microprocessor of vibration sensing module's electronic sensing card (622) of the system. ^" ■

The microprocessor of vibration sensing module's electronic sensing card (622) identifies the signal by performing some mathematical operations on the signal. The data out as a result this identification operation is saved into the external memory or PC connection module (700) through the Serial Communication Port of Vibration Sensing Module's Electronic Sensing Card (623), and in the Memory of Vibration Sensing Module's Electronic Sensing Card (625) at the same time. The processed data generated from the microprocessor of vibration Sensing Module's Electronic Sensing Card (622) is transmitted to the central command station PC for necessary information displaying and alarm functions through a wired or wireless communication system interface (628) via serial commucation I/O port of vibration sensing module's electronic sensing card (624).

As a result of the processing of vibration signal , along the railway line, the rail (200) between the vibration signal application point (300) and the vibration signal sensing point (500), a particular conclusion is reached about the rail's (200) physical integration. Loss or a reasonable change of the character of the vibration signal coming to the vibration signal sensing point (500) reveals the information in regards to the physical status of the rail (200) such as fit for use or unusable due to a rupture, fracture or a landslip.

Although the scope of the protection of this application is specified in the claims part and it is clear that a person who is skilled enough in the technic that is not limited to what is explained above as an exemplification can put on the innovation that present invention reveals by using similar structures and/or implement this structure used in related art to other similar purpose areas. Thus, obviously these kind of structures are lack of criteria that overlap the innovation and especially declared part of the technic.

Claims

1. The invention is a rail fracture or crack detection method that can be used for the determination of the rail faults in the area of railway systems technologies, and it is characterized by:

- the application of vibration signal to the rail body (200) with energy taken from the power supply (800) at vibration signal application point (300) by the help of the electromechanical vibration application module (100).

- driving the electromechanical vibration application module (100) by the help of vibration application module drive card (120) that works synchronously or asynchronously with the data transmitted over a communication line (400) extending alongside the railway track.

- the sensing of the vibration signal sent from the vibration signal entry application point (300) by the help of a vibration sensing module (600) at a distant point called vibration signal sensing point (500) on the same rail (200).

- reaching to the conclusion that whether the rail (200) has a crack or fracture by utilizing the signal picked by the the vibration sensing module (600) after this signal is evaluated by the electronic sensing card for vibration sensing module (620) that works synchronously or asynchronously with the data transmitted over a communication line (400) which is extending alongside the railway track.,

2. Being a rail fracture or crack detection method in compliance with Claim 1 , consisting of the mentioned electromechanical vibration application module (100), with the following operations performed accordingly .being driven by the driver interface of vibration application module's drive card (121) of the vibration application module drive module (120). the control and direction of the driver interface of vibration application module drive card (121 ) is handled by the microprocessor of vibration application module drive card (122).

all data generated during the operation of microprocessor of vibration application module's drive card (122) is being stored in the memory of vibration application module's drive card (123).

evaluation of data coming from the external communication line (400) with the help of the microprocessor of vibration application module drive card (122) by using the serial communication interface circuit of vibration application module drive card (124) for connection to wired or wireless communication interface circuit (125) during the driving process of the electromechanical vibration application module (100).

- transferring all data generated during the detection process to the external communication line (400) with the help of the microprocessor of vibration application module drive card (122) by using the serial communication interface Circuit of vibration application module drive card (124) for connection to wired or wireless communication interface circuit (125) during the driving process of the electromechanical vibration application module ( 00).

3. Being a rail fracture or crack detection method in compliance with Claim 1 , consisting of the mentioned vibration sensing module (600), with the following operations performed accordingly : transferring the vibration signal coming from the rail (200) into the to the electronic sensing card for vibration sensing module (620) located in the vibration sensing module (600) through to the vibration sensing module interface (610). converting the vibration signal which is carried into the electronic sensing card for vibration sensing module (620) to the electrical form by the vibration sensor

(626) .

Transferring the analog vibration signal coming from the vibration sensor (626) via the vibration sensing interface circuit (621) into the vibration signal processing unit (627) which is located in the electronic sensing card for vibration sensing module (620)

transforming the analog vibration signal in the vibration signal processing unit

(627) into the digital form and transferring this digital data into the microprocessor of vibration sensing module's electronic sensing card in the vibration signal processing unit (622).

- transferring the detection information about the crack or fractures on the rail (200) after the identification process on the raw vibration signal involving a number of mathematical operations performed by the microprocessor of vibration sensing module's electronic sensing card (622) to the external memory or PC connection module (700) via the serial communication port of vibration sensing module's electronic sensing card (623) and to the communication line (400) extending alongside the rail track, through to the serial commucation I/O port of vibration sensing module's electronic sensing card (624) via the wired or wireless communication system interface (628).