Research On Performance Of Rolls For Baosteel 2050 Mm Hot Strip Rolling Mill

Rolls are one of the important parts of rolling mill.Its performance is directly related to the surface quality and production efficiency of the strip steel product.At present,competition in steel market is fierce,the steel rolling production is gradually developing to more varieties,high quality,low consumption,high efficiency,and so on.These development trends are bound to bring higher demand on the use performance,service environment and grinding maintenance of the roll.Therefore,how to improve the full life cycle of the roll has become an urgent technical problem for many steel mills and roll manufacturing factory to be resolved.The present works mainly focus on the experimental investigation of mill roll material composition,metallographic microstructure,roll surface hardness,et al.of baosteel 2050 hot rough rolling and finish rolling.We summed up typical cases of the roll consumption,maintenance technology of grinding,and defects and failure of roll during use.On this basis,we proposed the optimized material selection of each mill stands and application and maintenance plan of rolls,which reduce the rolls consumption and improve using efficiency effectively to make them meet the demand for the production of strip steel with high surface quality.The main content and major findings include:(1)In rough rolling area,by comparing the components of different roll materials,metallographic microstructure,surface hardness,grinding process,and roll consumption,etc.of each roll frame,we concluded that:rolls of hot tool steel material is suitable for the R1 frame and completely replace the rolls of graphite steel.The performances of semi high speed steel rolls and high speed steel rolls are roughly equal.They can both meet the requirement of R2 frame.High chromium cast iron rolls meet the demands of R34 frame and are used continuously.(2)In finish rolling area,by comparing the components of different roll materials,metallographic microstructure,surface hardness,grinding process,and roll consumption,etc.of front frames and back frames of finish rolling,we concluded that:high speed steel rolls are fully applicable in the front frames of finish rolls and can replace the high chromium cast iron roll.Improved infinitely chilled roll works fine with the back frames of finish rolls and can replace conventional infinite chilled roll.(3)We concluded the typical cases of surface defects and failure of rolls during use over the years,then do qualitative analysis on surface defects and failure properties of rolls,and eventually form maintenance project and solution program to solve kinds of surface defect and failure of the rolls.