The empirical formula showing the relation of the B_S temperature to the chemical composition of steels was obtained from published isothermal transformation diagrams. The bainite transformation temperatures on the continuous cooling at the critical cooling rates corresponding to the beginning of the pearlite region and to the appearance of the fully pearlitic stage transformation were obtained from published CCT diagrams, and these temperatures (B₁ and B₂) were correlated to the chemical composition of steels for the wide range of the steel composition.