Thermal Stress Of Converter Waster Heat Flue

The converter is one of the main equipments in steel-making factories, during the working, there is generating numerous CO, a little CO2and other gas, containing Fe2O3, Fe and other fine kernel solid soot. The airflow rushes out the converter and enters the flue. The temperature is so high that it must be cooled for protecting equipments and increasing the purify efficiency. The equipments of collecting and leading the gas contain the removable hood and the fixed hood; they also have an action of cooling the gas. The heat surface of the flue contacts high temperature gas and is cooled by cooling water, so it forms very high temperature gradient and heat load, and the periodic thermal stress is the main reason for damage occurred. Through analysis the temperature and thermal stress of the flue under the workplace, it can guide the flue design, manufacture, use, improve its life, and it further significance is on the converter working for a long time steadily.The main aim of the thesis is researching the questions about the temperature field and the thermal stress of one180t LD converter waster heat flue of one steel factory. The thesis first establishes the flue model and solves the steady temperature field, then basing on elastic mechanical theory calculates the flue theory stress. The result is the thermal stress of the whole flue is very large; some position has been exceeded yield stress of the flue material. So basing on both elastic and plastic mechanical theory, using submodel technology calculates the theory stress again and finds part of the flue has been arisen plastic distortion. The life of the flue is very short.Considering the effects of physical properties by temperature, the paper compiles parametric modeling procedures based on structure features of the flue using APDL language, and calculates the influence of the gas temperature at the entrance, velocity of the water, clapboard thickness and cooling pipe thickness on temperature field and thermal stress of the flue, also compares the cooling efficiency at different parameter. The paper also calculates the flue temperature field and the thermal stress under vapor-cooling of the whole flue, compares the vapor-cooling capacity with water-cooling. The model and calculation procedure of the paper can be conveniently used for parameters design of flue and structural optimization design.