Maintain the normal operation of the train; use a spot temperature gun to conduct temperature tests on the train tracks

Thread Content

Tools: Fluke 568-2 dual-point thermometer. Tester: Jim Bertrand, University of Calgary, Canada. Tests: Temperature measurement with and without contact. http://bbs.dqccc.com/upload/2017/5/25/56313719-744d-478b-8422-40471e54d1bd.png Whether it’s transporting a whole trainload of bulk goods across states, moving finished products via long trains loaded with double-deck containers, carrying toxic chemicals to industrial parks using railway tank cars, or transporting passengers via busy suburban trains that move in and out of cities, it is essential to ensure that trains run on schedule along the tracks. The Fluke 568-2 two-point temperature gun is helping a Master of Science student in civil engineering at the Schulich School of Engineering at the University of Calgary in Canada with a study aimed at improving the safety of rail transportation. Depending on the properties of the rail surface, different temperature measurement instruments are required when measuring the rail temperature. Jim Bertrand used a Fluke 568-2 two-point thermocouple to measure the temperature of the rails on the rough, oxidized surfaces, and an external resistance temperature detector (RTD) to measure the temperature of the smooth running surface. By combining RTDs and infrared instruments, the emissivity of different surfaces of the rail can be calculated. “On days with plenty of sunlight, whether in summer or winter, the temperature of the railway tracks is usually 20-25 degrees Celsius (36-45 degrees Fahrenheit) higher than the temperature of the surrounding environment. In winter, the air temperature can be as low as -5°C (23F), while the temperature of the railway tracks can reach 20°C (68F). In summer, the air temperature can reach 30°C (86°F), while the temperature of the railway tracks can go up to 55°C (131°F). ”Bertrand said. “Modern railway rails are all welded into continuous sections, with no tolerance for expansion and contraction due to temperature changes. Whenever the rail temperature exceeds 45°C or 113°F, excessive axial forces cause the sections of continuously welded rails (CWR) to shift out of alignment, or to bend into an ’S’ shape on straight rails and into a ’C’ shape on curved rails. ”He added. Rail bending often occurs in trains traveling at normal speeds, and it frequently leads to rail deformation and wheel derailment. To ensure the normal operation of railways, railway authorities usually reduce the speed of all trains when the air temperature is above 30°C or 86°F. “My preliminary research indicates that the direction of the rail is an important factor in determining whether it will reach the critical rail temperature. The temperature difference between rails in different directions can often be as high as 15°F. This will result in certain sections of the rails reaching temperatures at which bending deformation can occur on some days, while at the same time, the rails in other directions are completely unable to absorb the energy required for bending deformation. Once this phenomenon is fully understood, it becomes possible to improve the safety of railway tracks and enhance the overall efficiency of rail operations. Bertrand has been working on this project since June 2004, and to date, although he has learned a lot, most of the empirical data has been collected from a facility in a suburb of Calgary. The Canadian Environment Department has installed numerous on-site rail track temperature measurement stations at the Atmospheric Research Centre located in southern Regina and northern Toronto, as well as at the Reference Climate Centres in Lethbridge, Alberta, and Fredericton, New Brunswick. Furthermore, the U.S. **National Oceanic and Atmospheric Administration (NOAA)** and the **National Centers for Environmental Information (NCDC)** (EC’s U.S. counterpart) have agreed to install on-site railway rail temperature monitoring stations in the United States, in order to quantify the climate heating mechanisms in high-temperature/dry climate conditions (Yuma, Arizona) as well as in high-temperature/humid climate conditions (Memphis, Tennessee). To distinguish the heat emitted from the rail surface, Bertrand needs more than just a simple measuring device. “The Fluke 568-2 spot thermometer has been able to assist me in my research primarily due to its high quality and reliability as a measuring instrument, as well as its 55:1 distance-to-spot ratio. Additionally, it allows the use of the 80PR-60RTD temperature probe in combination with the infrared measurement function of the Fluke 568-2 spot thermometer, which helps to determine the emissivity of exposed surface rails under various surface conditions. “Bertrand said. Last January, in the testing laboratory of Natural Resources Canada (NRCan) in Ottawa, Bertran measured the absorption properties of rails for visible and near-infrared short-wavelength (wavelength 300–2500 nm) radiation under various rail surface conditions. However, this experimental equipment cannot be used to measure the lower radiation energy with wavelengths in the 8-15um range coming from surfaces. Understanding the absorption and emission properties of rail steel is very important for developing energy balance equations that fully account for the heating required of exposed rails. In future research, Bertrand is investigating the possibility of using more precise Fluke point thermometers to determine differences in heating between the two sides of a rail, to identify differences in rail heating depending on the terrain on which they are installed, and to assess differences in the overall heating conditions of rails resulting from various combinations of ballast, rail sizes, as well as wooden and concrete sleepers. http://bbs.dqccc.com/upload/2017/5/25/94890f0b-4e6f-4254-b1dd-883df84d8040.png Testing was carried out using a spot temperature gun. http://bbs.dqccc.com/upload/2017/5/25/0ce770ae-bf4b-4fbc-823e-4e4bf1fc56e3.png Jim’s small rail testing device is combined with a weather station to measure rail temperatures, and the measured values are compared based on factors such as the angle of sunlight, ambient temperature, wind speed, and relative humidity. http://bbs.dqccc.com/upload/2017/5/25/caf71dd4-fb31-4ef3-bcff-f1256a82fcbf.png Check the temperature reading of the infrared thermometer after testing the rails.