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KF Flange

KF Union

In the 1950s, the Klein Flange company developed the KF Flange, or Quick Flange (QF) couplings, and ever since, it has been commonly used in vacuum and ultra-high vacuum applications. The easiest way to identify the union is its O-ring seal that is supported by a centering ring, and they come in sizes from 10mm to 50mm.

The union contains a KF Clamp, Two KF Flanges, and a KF Centering Ring with Seal. They can be mated with KF Bored Flanges, KF Blanks, and other KF Components. When the flanges are connected, the centering ring provides a seal that prevents air from leaking into the vacuum system, even in conditions with temperature and pressure.

KF flanges are easy to use because they do not require special tools to assemble or disassemble. 

Size Range

From KF10 to KF50

Internal Surface Finish

< 1μm

KF Flange

KF Flange

The KF Flanges will be welded to tubes, fittings and valves. It comes in different lengths but the most common are 12.7mm and 30mm. Available in SS 304 and SS 316L.

KF O Ring

The KF O ring sits in the middle of two KF Flanges to act as a seal to prevent leakages. Material is usually Viton.

KF Clamp

The KF Clamp is used to fasten two KF Flanges together. The clamp ring comes with a wing nut so no tools are required. Available in aluminium and SS 304.

KF Blank Flange

The KF Blank Flange is just a KF Flange without an opening, it can replace the KF flange to act as a cover to block flow. Available in SS 304 and SS 316L.

KF Centering Ring

The KF Centering Ring acts as a frame for the O Ring. An outer centering ring is also available if the KF Flange is to handle pressure as well as vacuum. Available in SS 304 and SS 316L.

KF Flange Dimensions | SS304 / SS316L | KF / NW / QF Series | High Vacuum Rated

Size
Welding Neck OD (mm)
Flange OD (mm)
Length (mm)
KF10
12.7 / 14
30
12.7 / 30
KF16
19.06 / 20
30
12.7 / 30
KF25
25.4 / 28
40
12.7 / 30
KF40
38.1 / 44.5
55
12.7 / 30
KF50
50.8 / 54
75
12.7 / 30
Have a Question?
 
contact us at nkeflow2020@gmail.com

or call  03-3323 5027

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