Abstract: Abstract: In order to study the performance changes of fireproof mud of typical elastic fireproof sealing material before and after fire, the influence on the combustion quality, backfire surface temperature and physicochemical properties of fireproof mud was studied according to the possible standard, electric and hydrocarbon fire situations in converter station. The physical and chemical properties focus on density, corrosion, water resistance, acid resistance, alkali resistance, oil resistance, heat resistance and resistance to freeze-thaw cycles. The results show that the maximum weight loss rate of fireproof mud is 20~35 min under the three fire heating conditions, and the mass loss of fireproof mud is nearly 50% when heated by the fire for 60 min. Fireproof mud has good heat insulation, can effectively prevent the transmission of flame and heat, after three kinds of fire heating,back fire surface temperature is far below the threshold value of 180 ℃. The temperature change of the backfire surface was monitored by the secondary heating of the fireproof mud after the fire, and the result was still far below the threshold value of 180℃, that is, the fire can still maintain good insulation without replacing the fireproof mud after the fire. The temperature rise of fire has an influence on the density, acid resistance and freeze-thaw cycling resistance of fireproof mud, but has little influence on the corrosion, water resistance, alkali resistance, oil resistance and heat resistance.

Key words: Key words: fireproof mud, fire heating mode, burning, mass loss, physical and chemical properties