The thin walled ring type flexible hose is extremely soft and flexible and it is the most suitable for the vacuum pipe system.
Nominal Diameter: 10mm-300mm
Length: 200mm-3000mm
Material: SUS304/SUS316/SUS21
Leakage of Helium: below 1*10-9Pa.m3/s.
These KF-40 Metal Hose Bellows Flex Coupling (10 inch, extra thin wall) vacuum fittings follow ISO-KF standards and have a flange size of NW-40. They are unsheathed and butt welded. Commonly used to build foreline vacuum plumbing and process systems. They are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of corrosive resistant stainless steel.