Abstract: The main cause of deformation of a converter shell is temperature rising of the converter shell, a economical and effective method to reduce the temperature and creep deformation is adopting a heat insulation layer of asbestos board. The temperature field and thermal stress of shells with different thicknesses of asbestos board at different temperatures were obtained for an 80 t converter at Chongsteel in China by heat transfer mathematical modeling. The calculated temperatures were in conformity with the measured data. When the thickness of asbestos board reaches 30 mm, the shell temperature could be controlled below 360℃, which is lower than the creep temperature of the shell material, and the thermal expansion stress of the shell is only 50 96 of that without asbestos board.