Heavy rails bear the high-frequency rolling and impact of heavy-load trains, and their performance is related to railway transportation safety. Continuous casting technology has become the core driving force for improving the performance of heavy rails with its unique process advantages.
In the steel liquid purification stage, the continuous casting technology effectively removes inclusions in the steel liquid through the retaining wall and dam structure of the tundish. Combined with the vacuum degassing technology, the hydrogen content in the steel liquid can be reduced to below 2ppm, greatly improving the purity of the steel liquid. Pure steel liquid reduces defects such as cracks and pores inside the heavy rails, and improves the intrinsic strength and fatigue resistance of the material.
The precise control of the casting speed and cooling process by the continuous casting technology brings a uniform and dense organizational structure to the heavy rails. The heavy rail continuous casting speed is stable at 0.8-1.2m/min. Combined with the gradient cooling of the secondary cooling system, the casting is evenly solidified from the surface to the center, avoiding organizational defects caused by uneven cooling. This uniform structure gives the heavy rail good toughness, making it less likely to break when subjected to the huge pressure of heavy-loaded trains.
The application of electromagnetic stirring technology further optimizes the performance of heavy rails. The alternating magnetic field promotes the movement of molten steel, breaks up dendrites, refines the grain structure, and reduces center segregation and looseness. Data shows that the heavy rails produced using electromagnetic stirring technology have improved wear resistance by 15% - 20%, significantly enhanced compressive strength, and greatly extended service life.
Compared with traditional die casting, the quality of the billets produced by continuous casting billet technology is stable, providing a high-quality foundation for subsequent rolling. The stable billet size and uniform internal structure ensure that the heavy rails meet high standards in terms of dimensional accuracy, strength, wear resistance, etc., and meet the stringent requirements of heavy-load railways for high performance and long life of rails.