Study On Improving Bottom Blowing Service Life Of 120t Converter

With the development of steelmaking technology,combined blowing technology has become the main technical means of converter steelmaking in the world,the top and bottom blowing converter is increasingly perfect today,the effect of bottom blown and components life is not synchronized with the life of converter,the major steel enterprises have different perspectives on this aspect,research in different degree,but the effect is not obvious.In this paper,the technology of bottom blowing system of 2#120 t converter in No.1 Steelmaking Plant of Guofeng County,Tangshan Province,has been reformed.The distribution of bottom blowing gas supply and bottom blowing element has been reformed.The bottom blowing component uses double ring seam gas supply element,the gas supply element uses two layers of metal ring seam to supply gas to the steel,the air supply area increases,and the air supply resistance decreases;the bottom of the furnace is provided with 6 bottom blowing devices,respectively,on time,at 6,8,10,12,14 and 16 points,and 0.45 times the diameter of the center,the arrangement method of the bottom blowing gas supply element has better metallurgical effect,and the local slag layer of the bottom blowing element is avoided to grow too thick,and the slag discharge maintenance is convenient when the local melting loss is larger.Based on the principle of fluid mechanics,the critical air supply parameters of bottom blowing lance at Guofeng converter are calculated under the assumption that the flow of gas in a uniform spray gun is adiabatic and frictional flow.By calculation,in Guofeng loading conditions,Guofeng bottom lance flow entrance pressure is 1.2MPa the lowest(gauge).In order to ensure the long-term existence of slag metal mushroom head,the minimum flow rate of bottom blowing gas stabilized under different mushroom head size and bottom blowing mode was calculated.The new development of the double seam bottom blowing elements formed of metal slag(mushroom)can prolong the service life of bottom blowing,is the key to realize synchronization of life and life of bottom blowing.Finally,this paper makes a detailed comparison and analysis of the improvement of the structure and distribution of bottom blowing elements and the metallurgical effects of the improved bottom blowing.