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With the large-scale development of marine equipment and the improvement of its performance, it is necessary to research and develop ultra-large sized titanium alloy ingots with high uniform composition. Based on the simulation results by MeltFlow, the 1st 12 tons ingot of Ti80 alloy is melted in Chinese and then was verified by two times. The chemical testing results show that the composition difference of the upper, middle and bottom of the ingot is less than 1000ppm, and the composition difference of the 17 positions of the riser is less than 3000ppm. Both of them are equivalent to that of the 5 tons ingot. Further, the macrosegregation at the riser was investigated and it is found that Al, Nb, Mo are enriched in the edge of the ingot and poor in the center of the ingot, whereas Zr has the opposite phenomenon. EDS was used to study the microsegregation between the grain boundary and interior. The results show that Nb and Mo are enriched within grain and poor at grain boundary. On the contrary, Al and Zr are enriched in grain boundary and poor within grain. The macro and micro segregation are consistent for Nb, Mo and Zr and opposite for Al. This is largely because the distribution of Nb, Mo and Zr is more largely depended on the solute redistribution at the solidification interface. By contrast, due to the highSsaturated vapor pressure at high temperature, Al is volatilized severe during the long time and high vacuum melting process and the solute redistribution at the solidification interface.