Abstract: Based on the basic principles of heat transfer, this paper carries out mathematical modeling and computational analysis on the temperature at the end of the suction valve pipeline at the top of a cryogenic ethylene storage tank in northern China in winter. By combining with the local atmospheric conditions, this paper analyzes whether the suction valve pipeline will freeze in extreme conditions, which may affect the reliability of suction valve. The calculation results indicate that even the heat input factors such as sunshine and heat conduction are fully ignored, the suction valve pipeline can still ensure that there will be no icing, and the reliability of the suction valve can be guaranteed with the designed appropriate extended length.

Key words: ethylene cryogenic storage tank, suction valve, heat transfer, freezing, reliability