Based on the thermal-mechanical coupling model, the distance from the critical position of the shrinkage cavity formation of the two bearing steel blooms to the meniscus is 22 and 19.78 m, respectively, and the critical center solid fraction is 0.7145 and 0.7033, respectively. Furthermore, the effects of superheat and casting speed on the critical value of shrinkage cavity formation are discussed. The results show that the two factors have a great influence on the critical position of shrinkage cavity formation in the former, but basically do not affect the critical solid fraction of shrinkage cavity formation. Finally, the industrial heavy reduction tests in different reduction intervals were carried out, and the results show that when the initial reduction position of the heavy reduction process is set before the critical solid fraction, it can not only eliminate the central shrinkage cavity of the bloom, but also improve the central segregation.
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