Bellows Hose Metal KF-25, 4 Inch, Flex Coupling, ISO-KF Flange Size NW-25, Stainless Steel
These KF-25 Bellows Flex Coupling vacuum fittings follow ISO-KF standards and have a flange size of NW-25. They are 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.
KF-25 Bellows Hose Flex Coupling
ISO-KF Flange Size: NW-25
Spring Rate: 44 lb/in
Common Dimensions: A = 4" (100mm)