Optimization Of Tundish Lining Refractory

With the rapid development of metallurgical industry,the thermal insulation effect of tundish is difficult to meet the needs of actual production,resulting in many defects and unstable quality of billets.In order to improve the thermal insulation effect of the tundish in a steel plant,numerical calculation research method is used to simulate and analyze the thermal insulation effect of the lining materials of the tundish in several different configuration schemes,and then simulation and experimental comparative research are carried out according to the optimized scheme and the original scheme of the steel plant.Finally,the nano thermal insulation plate after the field test is detected and analyzed,and the following conclusions are drawn:1.Keep the total thickness of the tundish unchanged.When the thickness of the nano thermal insulation plate increases by 1 mm,the outer wall temperature of the steel shell decreases by about 3.5 K,the permanent layer temperature increases by about 23K,and the working layer temperature increases by about 5 K.Both with the two schemes with the best insulation effect,there is only a 2 K difference in the temperature of the outer steel shell and a 104.6 W/m~2 difference in the heat flux of the tundish lining material.Meanwhile,the permanent layer and working layer will bear greater thermal stress and reduce the service life of the tundish.At the same time,considering the masonry cost of the tundish,The four-layer structure configuration scheme of 35 mm working layer+150 mm permanent layer+10 mm nano-insulated plate+35 mm steel shell is the most suitable for this steel plant,which can reduce the temperature of the outer steel shell 28 K and reduce the heat flux of the tundish lining material about1000.5 W/m~2;2.Keeping the total thickness of the tundish unchanged,the scheme of using nano thermal insulation plate as the thermal insulation layer can effectively reduce the temperature of the outer steel shell,and increase the temperature of all lining materials of the tundish except the steel shell,but the heating rate is lower than that of the original configuration scheme,and the heat flow density of the lining materials of the tundish is also lower than that of the original scheme.By comparing the field test and simulation results,it is found that the simulation calculation results and measurement results are basically consistent when the casting time of the tundish is less than 15000 s(the first five heats),and the error is less than 3%.When the casting time of the tundish exceeds15000 s,due to the problems such as the reduction of the working layer thickness and the rise of the thermal conductivity of the nano thermal insulation plate in the actual use,the simulation results and the actual results have an error of nearly 7%;3.Although there is no chemical reaction in the interior of the nano thermal insulation plate after use,there is a certain degree of thinning,volume density rise,porosity increase and other physical changes,resulting in the increase of thermal conductivity of the nano adiabatic plate,heat insulation capacity decreased.