Every time the temperature of a 500-meter rail rises by 1°C, the rail will stretch by 5.9mm. Due to the constraints of the fasteners, the temperature force generated inside the rail will also change. After the critical value is exceeded, the rail will deform laterally.
According to a large number of long-term measurement results, the highest orbit temperature is generally about 20C higher than the local highest temperature, and the lowest orbit temperature is roughly the same as the local lowest temperature. The magnitude and distribution of the rail temperature force of the seamless track is directly related to the rail temperature change range, and it is the main factor that affects the strength and stability of the seamless track, so the temperature change range of the steel rail becomes the seamless track Important information for road design, paving and maintenance. In the design of the seamless track, the local highest temperature +20C is generally taken as the local highest track temperature, and the local lowest temperature over the years is taken as the lowest track temperature. Rail temperature terms that are often used in work include intermediate rail temperature, locked rail temperature, and design locked rail temperature range.
The rail temperature meter is used to measure the temperature of the rail to prevent the rail temperature from becoming too high and the rail project cannot be carried out. When continuous measurement is required, the thermometer can be attached to the waist of the rail, but do not read when the train is passing. Because the train will produce a large airflow when the train is running, the surface temperature of the rail will drop. At this time, the value read has a large error. It takes three minutes to read the value of the rail thermometer, which is the actual surface temperature of the rail.