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 shall be checked after the pipeline connection and during the cold test, and the valve shall be regarded as qualified if it is not stuck.
5.Before the installation of remote control valve, it is necessary to strictly check whether the command signal is synchronized with the action of the valve actuator: "fully open" and "fully closed" positions are correct, and record the relationship between the opening command and the actual opening of the valve.
6.For cold angle valve with sleeve, special tools shall be used to fasten flange bolts during cold test.
7.During the cold test of the low temperature pneumatic diaphragm control valve, special tools should be used to fasten the flange bolts.
8.After the valve is installed, mark the process tag number nearby (both inside and outside the cold box) and check the mark.
