Thermal Stress Analysis Of Blast Furnace Wall

The long life of blast furnace has been the important sign and component part of the progress of modern pudding technology. For the improving of productivity and reducing of the cost of pudding production, the problem of improving the life of blast furnace has been prominent. According as the survey of the life of BF in our country, breakage of fireproofs inner lining flake and craze of the furnace casing is one of the important factors that impacts the longevity BF.The heat structure of blast furnace hearth is composed of refractory bricks and filling material and cooling stave and furnace shell. The heat surface of the blast furnace wall contacts high temperature furnace gas and is cooled by cooling water, so it forms very high temperature gradient and heat load. And both structure swelling stress and temperature head stress is the main reason for damage occurred. So analyses of blast furnace hearth's temperature distortion and thermal stress are the indispensable instrument to realize the microbial of the blast furnace. Through analysis the temperature and thermal stress of the blast furnace hearth under the workplace, it can guide the cooling stave design, manufacture and use and improves the life of blast furnace hearth, and it further extends the life of blast furnace.Furnace wall is simplied to be axisymmetric cylinder model.Though equivalent replacement of convective heat transfer boundary of water pipe surface in furnace hearth cooling stave and blast furnace shell, two simplified and equivalent method of calculating for one-dimension heat Conduction is established according to flat and plane axisymmetric cylinder heat conduct theory. It is based on the structure characteristics of the composite heat transfer of the cooling wall and the furnace shell. Method used to calculate furnace wall erosion line and temperature field of furnace wall is built. Arithmetic and example are given. It is calculated using FEM. Convective heat transfer boundary equivalent replacement and one-dimension thermal model simplification of furnace hearth cooling stave is precise.For the thermal expansion mechanics character of blast furnace hearth wall, according to linear theory of thermal elasticity, the formula of stress and deformation are deduced while bearing axisymmetric temperature and equal pressure. And it is applied for the stress and deformation analysis of un-cracked and reinforced shell of BF hearth. ANSYS is used to be calculated. Filling material and cooling stave is thermal expansion. The stresses of shell and linings born thermal expansion and deformation of elasticity are computed, and the calculation method of shell reinforcement is given. Inner lining erosion is inevitable while the BF is in service, which results in furnace wall temperature gradient filling out as well as thermal stress. Blast furnace shell will get into plastic stress and temperature distortion, and then thermal elasticity is inapplicability. According to theory of thermal plasticity, the formula of stress and deformation are deduced while bearing axisymmetric temperature and equal pressure. Different press inside are considered to calculate the thermal stress of blast furnace shell.These research is valuable for the design of blast furnace wall as well as disrepair of blast furnace shell.