The Structural Optimum And Application Of Refractory Material For 300t Ladle Lining

The ladle is usually not only a container for holding molten steel,but also a reactor for refining molten steel.It plays an important role in steelmaking process.The normal operation of the ladle affects not only the operation of the whole steel plant,but the safety.With the continuous development of metallurgical technology,the variety of smelting,the improvement of quality and the increase of CC ratio,the steel water stayed much more time in ladle.Especially,after refining the second time by using ladle outside the furnace as long as the use of LF furnace and other furnace,the operating requirement is becoming more and more severe,which led to the falling of the time of lining refractory.So,whether the ladle could take effect safely or not,is related with the performance and field construction technology of lining refractory.Based on a brief summary of the evolution of refractory materials for ladle lining in Baosteel,this paper focused on the analysis of the performance and application of the current ladle refractory.The inner lining of the steel ladle was divided into the permanent layer and the working layer,and each part was subdivided into the wall and the bottom of the ladle.The working layer of the wall is made up of the slag line and the molten pool,and it analyzed the use performance and repair mode of the steel according to the use environment of each part.It was found that the 300 t steel ladle used the high strength lightweight insulating brick and high aluminum refractory castable,which could have better insulation and resistance to steel water penetration.The micro cracks and damage caused by the whole casting process would be repaired with chrome fire mud and repair material,which prolonged the length of the permanent layer of ladle.The use of dry lining in steel ladle slag line brick could effectively improve the qualification rate of masonry brick seam,and the opening of void filling castable by opening the hole was useful to reduce the occurrence of cold steel between the working layer and the permanent layer.The performance of aluminum and magnesium refractory castables which were used in the overall pouring was good.The disadvantage was that the casting thickness was greatly influenced by the deformation of the shell.Castable could be made into precast blocks in order to achieve uniform thickness of work layer.In order to prolonging the service age of the overhaul of the ladle,the repair material could be used after which the cold steel was removed and then subsidized by the high alumina brick,and when the precast block of the wall of the wall was partially abnormal.In order to reduce the damage and the difficulty of the demolition caused by the frequent operation of the bottom air brick and the water mouth block,the magnesia carbon ceous surrounding brick could be built around the air permeable brick and the water mouth block.The overall service life of the permeable bricks could be prolonged because of the two ventilate bricks rotating and blowing.According to a series of research results of the specific conditions of the ladle,the safety performance of the ladle,the thermal insulation performance,and the longevity of the ladle,the carbon free cleaning and the low environmental pollution would be enlightened,with the selection of the lining refractory and the lining structure were provided.At the same time,combined with the current state policies of energy conservation and emission reduction,the future development direction of refractory materials for ladle lining in steel would work well.