Abstract: In this paper, the design and analysis of a new process technology which is lifting the vacuum tank to the work position with a original temperature 1 300 ℃ by off-line heating was performed using the thermal simulation module of SolidWorks Simulation. The finite element model of the vacuum tank including the shell and refractory lining was established. Three types of boundary conditions, in which the vacuum tank were preheated to 1 300 ℃ for 96 hours transiently，for 20 hours transiently and preheated to the steady state, were considered in the performed simulations. Then, the vacuum tank was left to cool naturally in 30 minutes. Finally, the temperature drop characteristics of the vacuum tank was analyzed. Results showed that the heat storage of the factory lining in the vacuum tank was obvious insufficient with the temperature condition in which the tank was preheated to 1 300 ℃ in 20 hours transiently. And the temperature of the top area was less than 800 ℃ after the cooling process. So it could not meet with the production requirements. For the other two temperature boundary conditions for the preheating, all parts of the vacuum tank exhibited a higher temperature than 800 ℃ after the cooling process, which could meet with the production requirements. Also, a good correlation was obtained between the temperature distribution of vacuum tank after preheating in 96 hours and cooling naturally in 30 minutes with the actual temperature distribution. From the economic point of view, the preheating solution in which the tank was preheated in 96 hours should be used in practical production. Computational results provided some theoretical guidance for the engineering application of RH vacuum furnace.

Key words: design analysis, thermal simulation, RH, vacuum tank