Regarding the models of ultra-low temperature valves
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Dear experts, I am currently creating a table of pipe grades for transporting liquid helium (with an operating temperature of -265°C). I know that at such a low temperature, aluminum pipes must be used. But what about valves? I only know that the valve for liquid nitrogen is DJ61F-40P, but according to the user manual provided by the manufacturer, the minimum operating temperature is -196°C; it shouldn’t be suitable for use with liquid helium, right?
For low temperatures, the coding method is based on the standard JB/T 308: the prefix D is used, and it is necessary to specify the medium being used as well as the operating temperature at the time of purchase.
Since the pipes are made of aluminum, can’t the valves also be made of aluminum? Or, after cryogenic treatment of stainless steel, it should be checked to see if it can be used; it’s best to consult the valve manufacturer for details
I am involved in the design of low-temperature and ultra-low-temperature valves. Since the pipes are made of aluminum, the valve bodies can also be made of aluminum or stainless steel. Given that the medium is liquid helium at -265°C, from a technical perspective, the valve disc seals, the gasket for the upper flange, and the packing seals should differ from those used in low-temperature valves operating at -196°C. The sealing materials are also different; if cold loss is a concern, you can ask the manufacturer to produce valves with vacuum jackets. For reference only; hope it is adopted!
The last edit to this post was made by City Boy on 2015-8-27 at 17:10; the value was adjusted by -265℃. In China, no one is capable of manufacturing valves for such low temperatures – it’s necessary to look abroad. I wonder whether aluminum pipes can withstand such low temperatures; after all, the pressure involved isn’t low either
It is best to use stainless steel for the valve body; 304L or 316L are the best choices