Effect of chemical heating process of 300t RH furnace on IF steel cleanliness

In order to study the influence of RH furnace chemical heating process on the cleanliness of IF steel.Forthe different stages of RH for chemical heatingup, a systematic analysis of the three indexes , including the total oxygen of slab , number density distribution of inclusions and inclusions size was made to have a quantitative evaluationof the impact of RH chemical heating node and temperature on steel cleanliness.The results showed that when theRH was chemical heating up , the cleanliness of the steel was worse, and the total oxygen of the billet was increasedby0.000 8% – 0.001 3%.Under the condition of different heating points at the same temperature , in the case of RHtemperature of 32 – 36℃ , the cluster inclusion size of 20 μ m for scheme 4 , was less than that of 30 μ m for scheme 5.Therefore , adopting the heating process of " pre – decarbonization and terminal decarbonization ", the inclusion sizewas less than that of " terminal decarburizing " heating process.In the production practice , if the molten steel enteredthe RH with low temperature , and the RH heating operation was unavoidable , the " pre – decarbonization and terminaldecarbonization " heating process should be adopted to reduce the influence of RH heating operation on the cleanliness of molten steel.