A Numerical Study of the Effect of Multiple Pouring on Macrosegregation in a 438-Ton Steel Ingot

Abstract

In present paper, a ladle-tundish-mold CFD model and a macrosegregation model were utilized to investigate the effects of the multiple pouring (MP) process on the macrosegregation in a 438-ton steel ingot. Firstly, the model was partially proved as compared to the measured carbon distributions along the transverse sections in the riser of ingot. Then, the comparison between the single pouring (SP) and MP process has been carried out to study their influences on the macrosegregation in ingot. Besides, the predicted macrosegregation results in MP process which introduced the improved riser fixed with an insulating sleeve were compared with that in traditional MP process. The traditional MP process leads to certain favorable initial carbon distribution in the mold, which has some favorable influence on suppressing the positive segregation in ingot. The holding time of the low carbon in the riser is the main factor to suppress the positive segregation in ingot. Improved insulating sleeve can prolong the holding time of the low carbon in the riser and release the positive segregation in the riser of ingot. Improvement of the insulating effect of the riser is an efficient method to control macrosegregation in large steel ingot.

Improving microstructure and segregation of steel ingot by inorganic heat absorption method

“…To solve the above problems, researchers have proposed a number of technical means to improve the solidification structure of large ingots. For example, Multilayer additive hot-compression bonding technology [16,17], Multi-Packing pouring technology [18][19][20], Electroslag [38] remelting technology [21], Hollow ingot technology [22]. These technologies have improved the defects of large ingots to a certain extent, but there are also some limitations.…”

Effect of Semisolid Metal Casting of Large Forging Ingots on Quality of Large-Sized Forgings Produced

“…Currently a number of procedures have been developed to improve the quality of cast metal. Methods of improving cast metal quality of large ingots through multi-ladle casting are discussed in the papers [5][6][7]. Secondary refining processes introduced at the "OMZ Spetstal" steel works are analyzed in [8].…”