The production process of steelmarking bearing steel by 100 t converter is studied and analyzed with tlhermody namics. The co-operating control process of carbon preservation

dephosphorization

and temperature control (C-P-T) in converter steelmaking process is optimized and established and applied to produce bearing steel. The results show that the dephosphorization reaction in furnace does not stop immediately when the selective oxidation temperature of phosphorus and carbon comes but has a slow decay process. In order to meet the need of deep dephosphorization

the optimal time of first slagging out in early stage of the new process should be controlled between 350 s and 380 s

and the temperature range is 1 360-1 437 ℃. The decarburization rate model predicts that the decarburization rate of bearing steel in the late stage of smelting is (0. 21% -0. 28% )/min. In order to keep the requirement of carbon preservation and temperature control

the catch carbon and reblow can be adopted in the end phase of blowing to further accurately control the temperature of liquid steel. According to the production data statistics of a furnace service period

the heat ratio of end carbon

phosphorus and temperature hit the target at the same time accounts for 76.67%

and the purity of liquid steel is greatly improved.