Research On The Lifetime Extension Of Large Blast Furnace Distributing Chute

For the bell less top of large size blast furnace,the daily charge volume of distributor is much larger than small & medium one.Therefore its distributing chute has a shorter service life under normal operation.The life time of the distributing chute is directly related to the reliability of whole bell less Top system.In case of distributing chute damage,it would inevitably lead to disruption of distribution rule in blast furnace with abnormal gas flow distribution,and then result in fluctuation of the blast furnace condition,which will affect the economic index of blast furnace production.Even blast furnace has to be shut down if damage badly.Therefore,it is very important to carry out force analysis for distributing chute to improve structure,material and technology according to different working conditions,which enhance working performance and prolong service life of distributing chute significantly.This thesis analyzed the common failure modes of distributing chute for large size blast furnace bell less top,and pointed out that impact wear is the universal damage for chute liners.In the thesis,distribution rule of chute was studied and it provided the data range of the chute as well as the vertical distance calculation formula from rotating center to chute bottom.The burden spatter in the chute was analyzed and it provided the basis of determination for baffle structure dimensions.It analyzed burden flow movement simulated by Discrete Element Software and figured out the positions of the second blanking point.Through above theory,it provided a basis for the structure improvement of the chute,researched on the technique development of the hard alloy liner.The anti-impact wearable liner was invented by using the technique of YG15 hard alloy brazing welding.Based on the above research results,it illustrated the design method to increase the service life of the distributing chute.Hereby a long life chute was developed.According to the feedback from actual application,it verified that the research results have significantly improved the life time of the distributing chute.