Ping Steel 45 # Steel Production Process Optimization

This article based on the actual production equipment situation in the second station of the PG. steel corp., the produce of the special steel: 45# steel has been researched. Using big drags quantity and single slag practice by the BOF dephosphorization technology, coordinating with the desulphurization process of the molten iron to pre-treat by single blow grain magnesium as well as optimizing the de-aeration alloy technology or the LF fining desulphurization process, we set the two process about the 45# steel production and contrast analyses from the BOF dephosphorization, the BOF end point situation, the inclusion control, castes aspects and semifinished product quality as well as different desulphurization effect, meanwhile the cost control has carried on the brief analysis to two crafts in.Through the research discovery, under two process implementation condition, the BOF using big dregs quantity and single slag practice, the dephosphorization all to be satisfy the 45# steel ingredient design request which the phosphorus is smaller than 0.025%, in which the lower molten iron Si, the more advantageous to the end product phosphorus control, namely the dephosphorization rate is higher; meanwhile the low end point carbon (tapping carbon) situation in two process, namely under the molten steel high oxygen condition, the steel the inclusion can achieve the quality requirement, but the LF fining process surpasses the inclusion the control as well as the end product sulfur change in the control. In the practice, under the molten iron pretreatment desulphurization smelts process, the end product sulfur number is higher than the LF fining end product sulfur number distribution slightly, but in the steel ingredient design level. Under the matching water mechanism of the continuous casting in same conditions, casts semifinished product quality satisfy the rolling request, the inclusion rank undulates in the between 0.5～1.0, also has the very great cost superiority, the ton steel cost drops 36 Yuan /t compared to the LF fining cost.The research also discover that the more specific water amount of the continuous casting can create the semifinished product drop in quality. Under the specific water amount control in 0.8～1.0L/kg and the tundish temperature control under 1525±10℃the condition, can realize casts the semifinished product quality optimization,...