CN115574724A - Railway turnout movable steel rail displacement monitoring device, monitoring method and evaluation method - Google Patents

Abstract

The invention discloses a displacement monitoring device, a monitoring method and an evaluation method for a movable rail of a railway turnout, comprising a displacement sensing device, a displacement monitoring device and an optical fiber grating demodulation device; the displacement sensing device is mainly used for sensing the slight displacement of the rail , the displacement monitoring device is mainly used to track and measure the displacement value in real time, and the fiber grating demodulation device is mainly used to record and feed back the displacement state. The invention has the advantages of anti-electromagnetic interference, long-distance transmission, etc., and the multiplexing and networking capabilities of the optical fiber displacement sensing technology are strong. Compared with the traditional electrical testing technology, it also has the characteristics of electrical insulation, corrosion resistance, and no drift. , which can meet the needs of long-term monitoring of high-speed railways. It has important practical significance for railway safety monitoring and maintenance. The invention also constructs an evaluation method for the displacement of the movable tongue/core rail of the high-speed turnout, which provides real-time data and on-site basis for the normal operation and safety maintenance of the railway.

Description

Displacement monitoring device, monitoring method and evaluation method of movable rail of railway turnout

technical field

The invention relates to the field of railway turnout measurement devices, in particular to a railway turnout movable rail displacement monitoring device, a monitoring method and an evaluation method.

Background technique

The safe and reliable conversion of the movable tongue/core rail in the high-speed turnout area is the key link to ensure the safety of railway operation, and it is an important indicator of the normal operating load of the track. Whether the movable tongue rail/core rail conversion in the high-speed turnout area is in place will affect the wheel-rail contact relationship, and then affect the wheel-rail interaction of vehicles passing through the switch and the safety and stability indicators of vehicle dynamics. If the switch rail/core rail cannot meet the conversion requirements, there will be insufficient displacement such as incomplete conversion and jamming, which will seriously endanger the driving safety. Therefore, real-time monitoring of the switch displacement of the switch rail/core rail is of great significance.

At present, the monitoring means for whether the movable switch rail/center rail conversion is in place in the turnout area is not accurate enough, the detection method is traditional, the monitoring results have large deviations, and hidden dangers to the safety maintenance of the railway still exist. However, the traditional electrical displacement sensor monitoring system has strong electromagnetic interference, which brings safety hazards to the operating environment of high-speed railways. It is urgent to develop a new set of high-precision displacement monitoring devices in order to track the displacement of the tip rail/core rail in real time, and provide for the railway. Safe operation provides on-site basis.

Contents of the invention

The technical problem to be solved by the present invention is to provide a movable rail displacement monitoring device for a railway turnout, a monitoring method and an evaluation method. Improve the safety monitoring and maintenance efficiency, reduce the risk of derailment, and effectively improve the economic and social benefits of railway operations.

In order to achieve the above object, the device and technical scheme designed by the present invention are as follows:

A displacement monitoring device for a movable steel rail of a railway turnout, comprising a displacement sensing device, a displacement monitoring device and an optical fiber grating demodulation device. The displacement sensing device is mainly used to sense the slight displacement of the track, the displacement monitoring device is mainly used to track and measure the displacement value in real time, and the fiber grating demodulation device is mainly used to record and feedback the displacement state.

The displacement sensing device includes a rigid rod whose end can move laterally with the rotation of the movable tip rail/core rail, one end of the rigid rod is fixedly connected with the tip rail/core rail bottom clamp, and the other end is connected with the spring. The spherical hinge is located in the middle of the rigid rod and acts as the fulcrum of the lever;

The displacement monitoring device includes a shrapnel base, a shrapnel, a fiber Bragg grating (FBG), an optical fiber, a spring and a casing of the displacement monitoring device. The spring connects the rigid rod and the shrapnel, the shrapnel is placed on the base of the shrapnel, two fiber Bragg gratings with the same central wavelength are engraved on the same optical fiber, the two Bragg gratings are respectively pasted on both sides of the shrapnel, and one end of the fiber is connected to the optical fiber Grating demodulation device.

The entire displacement monitoring device is installed on the track bed plate between the switch sleepers. The rigid rod is fixedly connected with the point rail/core rail bottom fixture. The spherical hinge is located in the middle of the rigid rod, which acts as a fulcrum of the lever and can also take into account the displacement monitoring. The need for waterproofing inside the device. The tip of the point rail/core rail is in a state of free expansion and contraction. Under the action of temperature force, the point rail/core rail has a certain free expansion and contraction displacement along the track direction. Since the spherical hinge can sense the displacements transmitted in all directions, the sensing device can meet the requirements of lateral conversion displacement monitoring under the condition that the point rail/core rail is free to expand and contract.

The optical fiber displacement sensing system of the present invention uses light waves as the carrier and optical fiber as the medium, has the advantages of anti-electromagnetic interference and long-distance transmission, and the optical fiber displacement sensing technology has strong multiplexing and networking capabilities, which is different from traditional electrical testing Compared with the technology, it also has the characteristics of electrical insulation, corrosion resistance, and no drift, which can meet the needs of long-term point rail/core rail conversion displacement monitoring for high-speed railways.

Furthermore, the shrapnel base is fixed at the bottom of the displacement monitoring device, the rigid rod and the shrapnel are connected by a spring, and two Fiber Bragg Gratings (FBG) connected in series to one optical fiber are pasted on both sides of the shrapnel.

Use the above device to monitor the displacement of the movable rail of the railway turnout. The monitoring method is as follows:

When the point rail/core rail rotates horizontally, it drives the rigid rod to rotate laterally, and the rigid rod rotates with the spherical hinge as the fulcrum of the lever, and the spring drives the shrapnel to deform. When the shrapnel deforms, the fiber Bragg gratings (FBG) on both sides of the shrapnel are subjected to tensile strain on one side and compressive strain on the other side.

与纵向应变

的关系为： Center Wavelength Shift of Fiber Bragg Grating

with longitudinal strain

The relationship is:

（1）

(1)

为光纤布拉格光栅的中心波长，

为光纤材料的弹光系数； In the formula,

is the central wavelength of the fiber Bragg grating,

is the elastic-optic coefficient of the fiber material;

The relationship between the center wavelength of the fiber Bragg grating (FBG) and the rotational displacement of the tip rail/core rail can be calibrated by formula (1), and the on-line monitoring of the rotational displacement of the tip rail/core rail can be realized.

The entire displacement monitoring device is installed on the track bed plate between the switch sleepers. The rigid rod is fixedly connected with the point rail/core rail bottom clamp. The rigid rod and the displacement monitoring device shell are coupled together through a spherical hinge, and the spherical hinge reaches the lever. The function of the fulcrum can also take into account the need for waterproofing inside the displacement monitoring device. At the same time, the tip of the point rail/core rail is in a state of free expansion and contraction. Under the action of temperature force, the tip rail/core rail has a certain free expansion and contraction displacement along the track direction. Since the spherical hinge can sense the displacements transmitted in all directions, the sensing device can meet the requirements of lateral conversion displacement monitoring under the condition that the point rail/core rail is free to expand and contract.

Another object of the present invention is to provide a method for evaluating the displacement of a railway turnout movable rail, comprising the following steps:

Step 1: Install the above-mentioned high-speed turnout movable tongue/core rail conversion displacement monitoring device on the track bed plate between the designated turnout sleepers, and at the same time calibrate the corresponding relationship between the switch point/core rail conversion displacement and the output center wavelength offset ;

Step 2: Divide the entire tip rail/core rail conversion time into n parts on average, each time interval is Δt , read the corresponding displacement value D _i of the movable tip rail/core rail during the conversion process according to a fixed time interval, and Record;

Step 3: Grab the recorded displacement data, construct a displacement-time based Di-T curve, and seek the displacement rule;

Step 4: Based on the monitoring data, formulate a technical plan for railway safety maintenance to ensure healthy operation.

In summary, the present invention provides a railway turnout movable rail displacement monitoring device, monitoring method and evaluation method, which have the following advantages and beneficial effects:

1. The optical fiber displacement sensing system uses light waves as the carrier and optical fiber as the medium. It has the advantages of anti-electromagnetic interference and long-distance transmission. Moreover, the optical fiber displacement sensing technology has strong multiplexing and networking capabilities, which is different from traditional electrical testing technologies. Compared with it, it has the characteristics of electrical insulation, corrosion resistance, and no drift, which can meet the needs of long-term monitoring of high-speed railways.

2. The rigid rod and the housing of the displacement monitoring device are coupled together through a spherical hinge. The spherical hinge acts as a fulcrum of the lever, and at the same time, it can take into account the need for waterproofing inside the displacement monitoring device.

3. The tip of the tip rail/core rail is in a state of free expansion and contraction. Under the action of temperature force, the tip rail/core rail has a certain free expansion and contraction displacement along the track direction. Since the spherical hinge can sense the displacements transmitted in all directions, the sensing device can meet the requirements of lateral conversion displacement monitoring under the condition that the point rail/core rail is free to expand and contract.

4. The device of the present invention has simple structure, easy operation and low cost.

Description of drawings

Fig. 1 is a schematic diagram of the logic framework of the device of the present invention;

Fig. 2 is the three-dimensional schematic diagram of the displacement monitoring device in the device of the present invention;

Fig. 3 is a schematic diagram of the installation position of the device of the present invention;

Fig. 4 is the partial schematic diagram of the installation of device of the present invention;

Figure 5a is a schematic diagram of the key components of the switch area of the turnout;

Figure 5b is a schematic diagram of the key components of the frog area of the turnout;

Fig. 6 is a flow chart of monitoring and evaluating the displacement of the movable rail of a railway turnout based on the device of the present invention.

In the figure, 1-displacement sensing device, 2-displacement monitoring device, 3-fiber grating demodulation device, 4-rigid rod, 5-spherical hinge, 6-shrapnel base, 7-shrapnel, 8-fiber Bragg grating, 9 - optical fiber, 10 - spring, 11 - shell of displacement monitoring device.

detailed description

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments, but the embodiments of the present invention are not limited thereto.

Example 1

According to the above technical solution, as shown in FIG. 1 , the present invention provides a railway turnout movable rail displacement monitoring device, which includes a displacement sensing device 1 , a displacement monitoring device 2 and a fiber grating demodulation device 3 .

The displacement sensing device 1 includes a rigid rod 4 whose end can move horizontally with the rotation of the movable tip rail/core rail. One end of the rigid rod 4 is fixedly connected to the rail bottom fixing device, and the other end is connected to the spring 10 . The spherical hinge 5 is located in the middle of the rigid rod and acts as a fulcrum of the lever;

As shown in FIG. 2 , the displacement monitoring device 2 includes a shrapnel base 6 , a shrapnel 7 , a fiber Bragg grating 8 , an optical fiber 9 , a spring 10 and a casing 11 of the displacement monitoring device. The spring 10 is connected to the rigid rod 4 and the shrapnel 7, the shrapnel 7 is placed on the shrapnel base 6, two fiber Bragg gratings 8 with the same central wavelength are engraved on the same optical fiber 9, and the two fiber Bragg gratings 8 are respectively pasted on the On both sides of the shrapnel 7 , one end of the optical fiber 9 is connected to the fiber grating demodulation device 3 .

As shown in Figure 3 and Figure 4, the entire displacement monitoring device 2 is installed on the track bed plate between the switch sleepers, the rigid rod 4 is fixedly connected with the point rail/core rail bottom clamp, and the spherical hinge 5 is located in the middle of the rigid rod 4 , to play the role of a lever fulcrum, and at the same time, it can take into account the requirement of waterproofing inside the displacement monitoring device 2 . The tip of the point rail/core rail is in a state of free expansion and contraction. Under the action of temperature force, the point rail/core rail has a certain free expansion and contraction displacement along the track direction. Since the spherical hinge 5 can sense the displacements transmitted in various directions, the sensing device can meet the requirements for monitoring the lateral conversion displacement under the condition that the point rail/core rail is free to expand and contract.

As shown in Figure 6, an evaluation method for a movable rail displacement monitoring device for a railway turnout comprises the following steps:

Step 1: As shown in Figure 5a or Figure 5b, in the turnout area, install the displacement monitoring device on the track bed plate between the designated turnout ties, and at the same time calibrate the corresponding relationship between the switching displacement of the switch rail/core rail and the output center wavelength offset;

Step 2: Divide the entire tip rail/core rail conversion time into n parts on average, each time interval is Δt , read the corresponding displacement value D _i of the movable tip rail/core rail during the conversion process according to a fixed time interval, and Records, such as Table 1;

Table 1 Displacement values during the conversion process of point rail/core rail

Step 3: Grab the recorded displacement data, construct a displacement-time based D _i -T curve, and seek the displacement law;

Step 4: Based on the monitoring data, formulate a technical plan for railway safety maintenance to ensure healthy operation.

Example 2

In this embodiment, on the basis of Embodiment 1, a plurality of displacement monitoring devices are installed in the switch sleeper sections corresponding to different top widths of the switch point rails/core rails to track the position of the movable point rails/core rails during long-term driving. Displacement values at different sections to examine whether it has monitoring point effects.

Other operation process and concrete technical scheme are all identical with embodiment 1.

Example 3

In this embodiment, on the basis of Embodiment 1 and Embodiment 2, the developed monitoring device is upgraded twice. In the device, the rigid rod 4 is connected with the spring 10 along the line direction (longitudinal direction), and in the displacement monitoring device 2 At the same time, another set of shrapnel, optical fiber, and Bragg grating are arranged. This device can simultaneously realize the online monitoring of the longitudinal free telescopic displacement of the point rail/core rail along the line and the horizontal conversion displacement of the point rail/core rail.

Other operation process and specific technical scheme are all identical with embodiment 1 and embodiment 2.

Example 4

In this embodiment, on the basis of Embodiment 1 and Embodiment 2, the developed monitoring device is upgraded again, and a contact device integrating data storage and transmission is installed in the device, so that the staff can collect and track data in real time indoors, and Complete data collation and analysis.

Other operation process and concrete technical scheme are all identical with embodiment 1, embodiment 2.

The specific implementation manners of the present invention have been described in detail above in conjunction with the accompanying drawings. It should be understood that the above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. Various improvements and changes made within the knowledge of those skilled in the art without departing from the principle and technical essence of the present invention shall be included within the protection scope of the present invention.

Claims (5)

1. A movable rail displacement monitoring device for railway turnout comprises a displacement sensing device (1), a displacement monitoring device (2) and a fiber bragg grating demodulating device (3);

the displacement monitoring device (2) is arranged on a track bed plate between the switch sleepers, the displacement monitoring device (2) comprises a displacement monitoring device shell (11), and the elastic sheet (7) is arranged in the displacement monitoring device shell (11) through an elastic sheet base (6); the top of the elastic sheet (7) is provided with a spring (10);

the fiber Bragg grating (8) is engraved on the optical fiber (9), the fiber Bragg grating (8) is respectively adhered on the elastic sheets (7), and one end of the optical fiber (9) is connected with the fiber Bragg grating demodulating device (3); the fiber grating demodulation device (3) records and feeds back the displacement state;

the displacement sensing device (1) comprises a rigid rod (4), the middle part of the rigid rod (4) is hinged on a displacement monitoring device shell (11), one end of the rigid rod (4) is fixedly connected with a switch rail/point rail bottom clamp and moves transversely left and right along with the rotation of the movable switch rail/point rail, and the other end of the rigid rod (4) is positioned in the displacement monitoring device shell (11) and is connected with a spring (10).

2. The railway turnout movable steel rail displacement monitoring device according to claim 1, wherein two fiber bragg gratings (8) are provided, and the two fiber bragg gratings (8) have the same central wavelength and are respectively adhered to two sides of the elastic sheet (7).

3. A device for monitoring the displacement of a movable rail of a railway switch according to claim 1, characterized in that the rigid bar (4) is hinged in the middle on the housing (11) of the device for monitoring the displacement by means of a spherical hinge (5).

4. A method for monitoring the displacement of a movable rail of a railway switch, which is characterized in that the device for monitoring the displacement of the movable rail of the railway switch according to any one of claims 1 to 3 is adopted, and comprises the following steps:

when the switch rail/point rail transversely rotates, one end of the rigid rod (4) is driven to transversely rotate, the rigid rod (4) rotates by taking a hinged part with the displacement monitoring device shell (11) as a fulcrum, and the other end of the rigid rod (4) drives the elastic sheet (7) to deform through the spring (10); when the elastic sheet (7) deforms, one side of the fiber Bragg grating (8) positioned on the two sides of the elastic sheet (7) is strained in a tensile mode, and the other side of the fiber Bragg grating is strained in a compression mode;

central wavelength shift of a fiber Bragg grating (8)

And longitudinal strain

The relationship of (1) is:

（1）

in the formula (I), the compound is shown in the specification,

is the central wavelength of the fiber Bragg grating (8),

is the elasto-optic coefficient of the optical fiber material;

the relation between the central wavelength of the fiber Bragg grating (8) and the switch rail/point rail rotational displacement is calibrated by the formula (1), and the on-line monitoring of the switch rail/point rail rotational displacement is realized.

5. A method for evaluating the displacement of a movable rail of a railway turnout is characterized by comprising the following steps:

step 1: installing a movable rail displacement monitoring device of a railway turnout in any one of claims 1 to 3 on a track bed plate between specified turnout sleepers, and calibrating the corresponding relation between switch rail/point rail conversion displacement and output center wavelength offset;

step 2: time-averaged division of the overall point/point transitionnPortions of each portion of time intervalΔtReading the corresponding displacement D of the movable point/point at regular time intervals during the transition _i And recording;

and step 3: capturing recorded displacement data and constructing D based on displacement-time _i -T curve, seeking displacement law;

and 4, step 4: and according to the monitoring data, a technical scheme for railway safety maintenance is formulated to ensure healthy operation.

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