Types and Applications of National Standard Rails
1. What are the common types of national standard steel rails?
Common types of national standard steel rails can be divided into crane rails, heavy rails and light rails according to the approximate weight in kilograms per meter. Crane rails, such as QU120, QU100, QU80, QU70, etc., are mostly made of manganese steel and are used for crane guide rails. Heavy rails commonly include 38kg/m, 43kg/m, 50kg/m, 60kg/m, 75kg/m, etc., with materials such as ordinary manganese - containing steel rails and copper - containing plain carbon steel rails. Light rails are used in mining, forestry, etc., such as 5kg/m, 8kg/m, 11kg/m, 15kg/m, 18kg/m, 24kg/m, etc., and are mostly made of carbon steel.
2. What are the differences in application scenarios of different types of national standard steel rails?
Crane rails are used for the running tracks of various cranes. Due to the need to bear large pressure and frequent lifting operations, they have high requirements for strength and wear resistance. For example, the QU series can meet such requirements. Heavy rails are widely used in railway main lines. For example, 60kg/m steel rails are often used in China's railway main lines. Because of their high strength, they can withstand the huge pressure generated by the high - speed and heavy - load operation of trains. Light rails are mainly used in lines with relatively small traffic volume such as mines and forest areas. Because of their light weight and low cost, they can meet the transportation needs of these areas, and the laying and maintenance are relatively simple.
3. What impact does the material of national standard steel rails have on their performance?
The materials of national standard steel rails are diverse, and different materials have different performances. Crane rails made of manganese steel have high strength and wear resistance and can withstand the long - term and frequent impact of crane operations. Among heavy rails, ordinary manganese - containing steel rails have certain strength and toughness; copper - containing plain carbon steel rails have good corrosion resistance and can extend the service life in some harsh environments. Among light rails, carbon steel materials have a low cost, but their strength and wear resistance are relatively weak, which is suitable for lines with small traffic volume and low frequency of use.
4. What are the standard lengths of national standard steel rails and how to choose?
The standard lengths of national standard steel rails are 12.5m and 25m. 25.0m standard - length steel rails are used for extra - heavy and heavy rails. Because there are few joints when laying, the bumps during train operation can be reduced, and the track smoothness can be improved, which is suitable for large - traffic - volume lines such as railway main lines. For other types of tracks, such as some branch railway lines or lines with relatively low requirements for tracks, 12.5m standard - length steel rails can be used. While meeting the transportation needs, the laying cost can be reduced, and the construction and maintenance are convenient.
5. How to judge whether the quality of national standard steel rails is qualified?
To judge the quality of national standard steel rails, first look at the appearance. The surface should be smooth without defects such as cracks, bubbles, and scabs, and the dimensional deviation should meet the standard. Hardness testing can be carried out to judge whether its strength meets the standard, and different types of steel rails have corresponding hardness requirements. Flaw detection can also be carried out. Technologies such as ultrasonic waves are used to detect whether there are hidden dangers such as cracks inside. In addition, check the chemical composition of the steel rail to ensure that the content of each element meets the standard of the corresponding material. These detection methods are comprehensively used to judge whether the quality is qualified.