Materials and manufacturing of Steel rail

Material composition

1.U71Mn: This is a steel grade with a high manganese content, which is widely used in heavy rails due to its good wear resistance and fatigue resistance.

2.900A/1100: This material has high strength and good weldability, and can handle higher axle loads, suitable for applications that require higher efficiency.

The manufacture of rails usually involves the following steps:

1. Smelting and casting: First, the raw materials (iron ore, scrap steel, etc.) are smelted into liquid steel in the steel mill and formed into billets by continuous casting or die casting.

2. Rolling: The billets are heated and sent to the rolling mill for hot rolling to form them into the desired cross-sectional shape. In this process, the microstructure and mechanical properties of the rails can be adjusted by controlling the rolling temperature and speed.

3. Heat treatment: In order to further improve the performance of the rails, they can be heat treated, such as normalizing, tempering or online heat treatment (OHT). In particular, online heat treatment technology can directly quench and temper the rails on the production line to obtain a uniform and excellent microstructure.

4. Finishing: After heat treatment, the rails also need to undergo a series of finishing processes such as straightening, grinding, and flaw detection to ensure that the dimensional accuracy and surface quality meet the standard requirements.

5. Inspection and packaging: Finally, each rail undergoes strict quality inspection, including chemical composition analysis, mechanical property testing, and non-destructive testing. Qualified products will be marked and properly packaged, ready for shipment.