Remotely operated valve for cryogenic material - has sealing bellows to keep liq. gas separate from working mechanism

摘要

The valve incorporates an insulating cover for the cryogenic fluid e.g. liquid hydrogen or helium. Operation of the valve does not lead to the fluid being heated up. The valve housing surrounds a pressure chamber and the operating piston has an end face that operates the valve plate. A bellows seals off the fluid from the centre of the housing. the pressure chamber has a pneumatic connection through the insulating cover to a pressure source. When there is no pressure in the chamber, the valve plate is held by a return spring.