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SKU KF25RING
USA Lab
Aluminum KF25 Vacuum Pump Flange Centering Ring
$5.00
In stockAluminum centering ring fitted with a rubber O-ring, sized for KF25 (NW25) quick-flange vacuum joints. It sits between two mating KF25 flanges and carries the O-ring on the joint centreline so a wing-nut clamp can pull the pair into a repeatable seal. Supplied as the ring only; KF clamps are a separate listing.
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Description
Aluminum KF25 centering ring with a rubber O-ring, for KF25 (NW25) quick-flange vacuum connections.
A KF joint is made from three parts: two matching flanges, one centering ring and one clamp. The centering ring locates the O-ring concentrically between the flange faces so that tightening the clamp compresses the elastomer evenly rather than pinching it to one side. KF25 is the most common size on bench rotary vane pumps and short vacuum lines, so this is usually the ring that gets replaced most often.
Specifications
Flange size: KF25 (NW25)
Ring material: Aluminum
Seal: Rubber O-ring
SKU: KF25RING
KF16, KF25 and KF40 rings are not interchangeable; order the size that matches your flange. Wing-nut clamps in KF16, KF25 and KF40 are listed separately.
Frequently asked questions
What flange size does this fit?+
KF25, also written NW25. KF16, KF25 and KF40 rings are dimensionally different and are not interchangeable, so match the ring to the flange size stamped on your fitting.
What is it made from?+
An aluminum ring carrying a rubber O-ring. Part number KF25RING.
Is a clamp included?+
No. This listing is the centering ring alone. KF wing-nut clamps are sold separately in KF16, KF25 and KF40.
What else do I need to make up a KF25 joint?+
Two KF25 flanges, this centering ring, and one KF25 clamp. The ring and clamp are the two consumable parts of the joint.
Is the O-ring material specified?+
The manufacturer's description states a rubber O-ring but does not name the specific elastomer compound. If your process requires a defined elastomer for chemical or temperature compatibility, confirm the compound before ordering.
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