In general, WEKA Q valves have the same characteristics as the bellow valves. However, they are not sealed metallically to the outside, but with a soft seal. Typically, they are used for liquid nitrogen applications at temperatures up to 80K.
Their design is optimised for the ingress of heat.
Housing and parts in contact with the medium: 304/304L, 316/316L stainless steel
Seat sealing: PTFE, other sealings for special requirements
Control cone: Aluminium bronze
Each valve is subjected to a pressure test at 1.5*PN and integrally tested for tightness to the outside using helium. The tightness below the seat is also tested for the nominal pressure or for an operating pressure defined by the customer.
Liquid nitrogen, LNG