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SKU KF40RING
USA Lab
Aluminum KF40 Vacuum Pump Flange Centering Ring
$5.00
In stockAluminum centering ring fitted with a rubber O-ring, sized for KF40 (NW40) quick-flange vacuum joints. It sits between two mating KF40 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 KF40 centering ring with a rubber O-ring, for KF40 (NW40) 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. KF40 is the larger of the three common bench sizes and is normally chosen where conductance, not convenience, sets the line size.
Specifications
Flange size: KF40 (NW40)
Ring material: Aluminum
Seal: Rubber O-ring
SKU: KF40RING
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?+
KF40, also written NW40. 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 KF40RING.
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 KF40 joint?+
Two KF40 flanges, this centering ring, and one KF40 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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