Jun 14, 2020
Cryogenic valves: Bellows valve 4K
WEKA check valves of the CCV type are typically used for liquefied gases such as He, Ne, H2, N2 or Ar. They are designed for a nominal pressure PN up to 25 bar and for a temperature range from 4 K to 323 K. Standard versions are the nominal diameters DN6 to DN200 and with weld-on ends, optionally with extensions or also with flanges.
In order to avoid undesired oscillations in the system, the check valves can also be designed with a small seat bypass borehole.
Housing, insert: Grade 316L stainless steel
Spring: Grade 316 stainless steel
Seat sealing: PE-UHMW, PTFE or PCTFE depending on the application
The opening pressure depends on the nominal diameter and on the installation position and is typically between 5 and 50 mbar.
Larger opening pressures are also possible if necessary.
Each valve is subjected to a pressure test at 1.5*PN and integrally tested for tightness to the outside using helium. Tightness to the inside and opening properly in the flow direction are also tested and documented.
The typical use of bellows valves is in helium or hydrogen condensers.