Study On High-carbon Process Of GCr15 Bearing Steel In Converter Smelting

With the change of user demand and upstream industry,continuous improvement of steel product quality and reduction of production cost are the continuous requirements for steel production.The converter plays a role of connecting the preceding and the following in the production process,and is an important link in the actual production.Based on a domestic enterprise of 80 t converter GCr15 bearing steel as the research object,in the past has not been importance to improve the finish with the carbon content of molten steel in the converting method,combining the reality of enterprises and related at home and abroad on the basis of consulting literature materials,carry out the "high carbon" refining the high carbon technology research,for enterprises to open up a new way,efficient and low cost of steelmaking.By using the method of big data statistics,the advantages of "high-carbon" technology are demonstrated by comparing the process parameters before and after "high-carbon".Based on the "high carbon" process of converter production test data,respectively investigates the high phosphorus content in hot metal(0.131% ? 0.160%),temperature,dephosphorization period(early)converting oxygen blowing,dephosphorization final a fall(using "double slag" pour slag)for the first time,such as temperature,dephosphorization and decarburization quantity,to the early stage of the converter dephosphorization and decarburization rate effect.The results showed that: at the end of dephosphorization period,the first pour temperature was controlled between 1350? and 1380?,the Si content of molten iron was controlled below0.45%,and the dephosphorization rate reached more than 45.0% when the oxygen content was higher than 1200m3.The average dephosphorization rate and decarburization rate were 43.0% and 24.7% respectively at the dephosphorization stage of 50 groups of furnaces.The end temperature of converter,the content of iron oxide in slag,basicity and the carbon and oxygen accumulation of the end point in the data of one-time high carbon drawing process were investigated.The results show that when the end point temperature is controlled at 1620 ? ? 1650 ? and the phosphorus content is below0.012%,the ratio of the end point carbon content at 0.15% ? 0.25% is 40.0%,and the content of Fe O in the end point slag is 16.0% ? 20.0%.When the basicity of slag is controlled at 3.81,the highest value of dephosphorization rate is about 95.4%.The results show that when the oxygen content is controlled below 0.0136%,the carbon content is 0.18%.The process of one-time supplementary blowing for the phosphorus or temperature in the end-point molten steel with high carbon content not meeting the tapping requirements was investigated,the results show that the average phosphorus content is 0.008%,the average temperature can be controlled at 1652 ?,and the carbon content is 0.16% ? 0.23%.