Air separator

1. Valves in cold box shall be installed after all vessels are in place and before pipeline installation. 2. The cold valve in the cold box shall be installed together with its corresponding support. The valve stem of cryogenic liquid valve should be inclined upward by 10°to 15°. When the pipe is welded with the valve body, the valve should be closed first. Take cooling measures to make the temperature of the valve body not higher than 200℃ during welding, so as to avoid the deformation of the valve seal and affect the normal use of the valve. 3. When installing the valve, pay attention to the arrow direction on the valve body, which should be consistent with the medium flow direction. On special occasions, some cold Angle Globe Valves and straight through heating valves outside the cold box make their directions opposite (according to the marks on the process flow chart). 4. The valve shall be opened and closed flexibly after installation. The valve opening and closing state

Such failures include "cooling leakage" and freezing of valve packing, leakage of valve seat and pipe connecting flange, and leakage of valve screw sleeve at both ends of tinned thread. The stem packing is usually located in the packing groove of the stem close to the cold box wall. When the packing is not uniform or tight, and the valve stem is not straight or round, cryogenic liquid or gas will leak along the packing gap. As a result of cold transfer to the outside, the water in the air will freeze on the packing, thus freezing the valve stem. In this case, the valve can only be opened and closed by heating the filling with steam or hot water. However, after opening and closing the valve, the water accumulated in the packing will freeze again. The valve stem is usually twisted and the handwheel is broken due to the hard work of valve opening and closing. Therefore, after the maintenance of the valve, the packing should be evenly and tightly packed, and the compression nut should b