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In order to obtain distribution characteristics of liquid nitrogen boiling sections in freezing pipe, an in-situ liquid nitrogen freezing experiment was carried out in this study. There are opened holes on the liquid nitrogen supplying tube. The temperature and distribution of liquid nitrogen boiling sections can be obtained through the temperature measuring tube installed inside the freezing pipe. The study shows that firstly, the export temperature of the freezing pipe with opening-holes on supplying tube is lower than that of traditional pipe when liquid nitrogen boiling sections appear in the freezing pipe. Secondly, with the increase of liquid nitrogen perfusion, liquid nitrogen boiling sections appear initially on the top of opening-holes supply pipe, and gradually extend down the pipe. It is difficult to obtain the boiling situation on the sections with no opened-holes in the upper freezing pipe. Thirdly, the frozen wall is non-uniform because of the amount difference of liquid nitrogen gasification in different positions. The test results show that the adjustment on the open-holes sections of the supply pipe and the amount of liquid nitrogen supply can effectively determine the distribution characteristics of the liquid nitrogen boiling sections. The adjustment of liquid nitrogen boiling sections, which may improve the efficiency in liquid nitrogen usage, can enhance the rapid freezing. [ABSTRACT FROM AUTHOR]