A method for measuring the internal temperature of a rail

Abstract

A method for measuring the internal temperature of a rail, belonging to the technical field of rail temperature measurement, comprises the following steps: S01: Obtain the resistance value of the rail to be measured; S02: Use a temperature sensor to measure the ambient temperature of the rail; S03: Input the measured resistance value into the measurement temperature algorithm to obtain Rt; S04: Input the measured ambient temperature into the resistance-temperature coefficient database to obtain the corresponding resistance-temperature coefficient α value; S05: Calculate the internal temperature t of the rail. By measuring the resistance value and ambient temperature of the rail to be measured, using the established resistance-temperature coefficient database to obtain the resistance-temperature coefficient α value, and calculating the internal temperature of the rail, the internal temperature of the rail can be accurately measured.

Description

Technical Field

[0001] The present invention belongs to the technical field of rail temperature measurement, and particularly relates to a method for measuring the internal temperature of a rail. Background Art

[0002] In the field of rail temperature measurement, the existing measurement methods usually measure the surface temperature of the rail. For example, in the published Chinese patent application "A Portable Rail Temperature Measuring Instrument and Its Temperature Measuring System" (CN112345095A), its working principle is to measure the surface temperature of the rail using a temperature sensor. In the published Chinese patent application "New Type Rail Temperature Measuring Instrument" (CN104330163A), its working principle is also to measure the surface temperature of the rail using a temperature sensor. At present, there are many methods for measuring the surface temperature of the rail, but they all measure the surface temperature of the rail, and less attention is paid to the measurement of the internal temperature of the rail. However, under natural conditions, the temperature difference between the sunny side and the non-sunny side of the same rail under natural light is more than 4°C. For the rail transit maintenance department, there are relevant requirements for the locked rail temperature. In the measurement of the locked rail temperature, the actual rail temperature of the rail is an important parameter. The rail transit maintenance department has a limited value requirement for the temperature of the rail. Only measuring the surface temperature of the rail cannot represent the actual temperature of the rail. Therefore, how to accurately measure the temperature of the rail is a major problem for the rail transit maintenance department. Summary of the Invention

[0003] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for measuring the internal temperature of a rail. By measuring the resistance value and ambient temperature of the rail to be measured, obtaining the resistance temperature coefficient α value using the established resistance temperature coefficient database, and calculating the internal temperature of the rail, the internal temperature of the rail can be accurately measured.

[0004] To achieve the above object, the main technical solutions adopted by the present invention include:

[0005] A method for measuring the internal temperature of a rail, comprising the following steps:

[0006] S01: Obtain the current temperature resistance value Rt of the rail to be measured;

[0007] S02: Obtain the ambient temperature t' where the rail to be measured is located;

[0008] S03: Input the obtained ambient temperature t' into the resistance temperature coefficient database to obtain the corresponding resistance temperature coefficient α value;

[0009] S04: Calculate the internal temperature t of the rail according to formula (1);

[0010]

[0011] Wherein: Rt is the current temperature resistance value; R(20) is the resistance value of the steel rail at 20°C; α is the resistance temperature coefficient.

[0012] Further, in the step S01, the current temperature resistance value of the steel rail to be measured is obtained by measuring the resistance of the steel rail to be measured using a micro-ohmmeter.

[0013] Further, in the step S02, the ambient temperature t' of the steel rail to be measured is obtained by using a temperature sensor to measure the ambient temperature of the steel rail.

[0014] Further, in the step S03, the method for establishing the resistance temperature coefficient database is as follows:

[0015] Place the same steel rails A and B together in a constant temperature oven. Set a temperature sensor inside steel rail B. When the temperature measured by the temperature sensor inside steel rail B is consistent with the set temperature t'' of the constant temperature oven, use a micro-ohmmeter to measure the resistance value of steel rail A to obtain the resistance value Rt' of steel rail A at the temperature t''. Then calculate the resistance temperature coefficient α value according to R(20) = Rt' / (1 + α(t'' - 20)); wherein: t'' is the set temperature of the constant temperature oven; R(20) is the resistance value of the steel rail at 20°C; change the temperature of the constant temperature oven body, and use the same method as above to calibrate the resistance temperature coefficient database of the steel rail and establish a relationship database between temperature and the resistance temperature coefficient of the steel rail.

[0016] The beneficial effects of the present invention are: The present invention first establishes a resistance temperature coefficient database through laboratory tests. In the laboratory stage, two same steel rails A and B are used. Steel rail B is used to measure the internal temperature of the steel rail, and steel rail A is used to measure the resistance of the steel rail when the internal temperature of the steel rail reaches the set temperature. The established database establishes a relationship between the resistance of the steel rail and the internal temperature, providing a basis for calculating the internal temperature of the steel rail on-site.

[0017] Measure the resistance value and ambient temperature of the steel rail to be measured on-site, obtain the resistance temperature coefficient α value by using the established resistance temperature coefficient database, and calculate the internal temperature of the steel rail. The internal temperature of the steel rail can be accurately measured. Using the method of the present invention to measure the internal temperature of the steel rail is convenient to operate, has high test efficiency, and the test result accuracy rate is relatively high. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the steel rail temperature measurement of the present invention.

[0019] Components in the figure: 1 is the steel rail; 2 is the micro-ohmmeter; 3 is the communication cable; 4 is the test host 5 is the temperature sensor. Detailed Embodiment

[0020] In order to better explain the present invention for easy understanding, the present invention will be described in detail below with reference to the drawings through specific embodiments.

[0021] The present invention relates to a method for measuring the internal temperature of a steel rail, comprising the following steps:

[0022] S01: Obtain the current temperature resistance value Rt of the steel rail to be measured; obtaining the current temperature resistance value of the steel rail to be measured is to measure the resistance of the steel rail to be measured using a micro-ohmmeter. The test is as Figure 1 shown. Connect the micro-ohmmeter 2 to the steel rail 1, and connect the micro-ohmmeter 2 and the temperature sensor 5 to the test host 4 through the communication cable 3.

[0023] S02: Obtain the ambient temperature t' of the steel rail to be measured; obtaining the ambient temperature t' of the steel rail to be measured is to measure the ambient temperature of the steel rail using the temperature sensor 5.

[0024] S03: Input the obtained ambient temperature t' into the resistance temperature coefficient database to obtain the corresponding resistance temperature coefficient α value; the method for establishing the resistance temperature coefficient database is as follows:

[0025] Place the same steel rails A and B together in an incubator, and set a temperature sensor inside the steel rail B. When the temperature measured by the temperature sensor set inside the steel rail B is the same as the set temperature t'' of the incubator, use the micro-ohmmeter to measure the resistance value of the steel rail A to obtain the resistance value Rt' of the steel rail A at the temperature t''. By setting the steel rail B and detecting that the internal temperature of the steel rail B reaches the set temperature t'' of the incubator, it is ensured that when measuring the resistance of the steel rail A, the internal temperature of the steel rail A is the same as the external temperature.

[0026] Then calculate the resistance temperature coefficient α value according to R(20) = Rt' / (1 + α(t'' - 20)); where: t'' is the set temperature of the incubator; R(20) is the resistance value of the steel rail at 20°C, which is the resistance value measured when the internal temperature of the steel rail reaches 20°C in the laboratory incubator; change the temperature of the incubator body, and use the same method as above to calibrate the resistance temperature coefficient database of the steel rail and establish a relationship database between temperature and the resistance temperature coefficient of the steel rail.

[0027] S04: Calculate the internal temperature t of the steel rail according to formula (1);

[0028]

[0029] where: Rt is the current temperature resistance value; R(20) is the resistance value of the steel rail at 20°C; α is the resistance temperature coefficient.

[0030] Example 1

[0031] Select a 1m long 60kg / m steel rail on-site to measure its temperature and record the temperature of the steel rail. The test environment is selected as a conventional environment, that is, a specific environment such as non-direct sunlight or under the shade of a tree. Rust removal treatment is carried out at both ends of the 1m steel rail. After the rust removal is completed, the steel rail is connected in series into Figure 1 the measurement circuit in. The current temperature resistance value Rt of the steel rail measured by the micro-ohmmeter 2 is 43.7×10 -6 μΩ. The ambient temperature is 25℃ measured by the temperature sensor 5. According to the database, the temperature coefficient of resistance α = 1.5×10 -6 (Ω / ℃). The resistance R (20) of the steel rail at 20℃ is 34.4×10 -6 μΩ. Substitute it into formula (1) to obtain the internal temperature t of the steel rail,

[0032]

[0033] The internal temperature of the steel rail is 26.2℃.

[0034] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for measuring the internal temperature of a rail, characterized in that, It includes the following steps: S01: Obtain the current temperature resistance value Rt of the steel rail to be measured; S02: Obtain the ambient temperature t' of the steel rail to be measured; S03: Input the obtained ambient temperature t' into the resistance temperature coefficient database to obtain the corresponding resistance temperature coefficient α value. In step S03, the establishment method of the resistance temperature coefficient database is as follows: Place the same steel rails A and B together in an incubator. Set a temperature sensor inside steel rail B. When the temperature measured by the temperature sensor inside steel rail B is consistent with the set temperature t'' of the incubator, use a micro-ohmmeter to measure the resistance value of steel rail A to obtain the resistance value Rt' of steel rail A at temperature t''. Then calculate the resistance temperature coefficient α value according to R(20) = Rt' / (1 + α(t'' - 20)); where: t'' is the set temperature of the incubator; R(20) is the resistance value of the steel rail at 20°C; Change the temperature of the incubator body and use the same method as above to calibrate the resistance temperature coefficient database of the steel rail and establish a relationship database between temperature and the resistance temperature coefficient of the steel rail; S04: Calculate the internal temperature t of the steel rail according to formula (1); （1）； Where: Rt is the current temperature resistance value; R(20) is the resistance value of the steel rail at 20°C; α is the resistance temperature coefficient.

2. The method for measuring the internal temperature of a steel rail according to claim 1, characterized in that: In step S01, the current temperature resistance value of the steel rail to be measured is obtained by measuring the resistance of the steel rail to be measured with a micro-ohmmeter.

3. A method for measuring the internal temperature of a rail according to claim 1, characterized in that: In step S02, the ambient temperature t' of the steel rail to be measured is obtained by using a temperature sensor to measure the ambient temperature of the steel rail.

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