KF-40 (NW40) is used where a vacuum line needs more flow than KF-25 allows: inlets and forelines on larger pumps, roughing lines to chambers and process equipment, and main lines on bigger lab and industrial systems. KF fittings are also called QC (quick connect) or QF (quick flange) fittings.
Which KF-40 part do I need?
- Connect two KF-40 parts: Connecting two KF-40 flanges requires one KF-40 clamp and centering ring set.
- Connect to a threaded port: Use a KF-40 to NPT adapter, available in male or female threads from 1/8" to 2".
- Connect to hose: Use a KF-40 hose barb adapter (3/8" to 1") or a PVC smooth hose adapter (3/4", 1", 1.25" or 1.5"). Our silicone vacuum tubing fits our hose barbs.
- Add flexibility or absorb vibration: Use a KF-40 stainless bellows, available from 100 mm to 2500 mm.
- Change direction or split a line: Use a KF-40 elbow, tee or cross.
- Change flange size: Use a straight reducer to KF-16, KF-25 or KF-50, or a reduced tee to KF-16 or KF-25.
- Close off a port: Use a KF-40 end blank.
Frequently asked questions
What are LoCo's KF-40 fittings made of?
All LoCo Science fittings come standard in heavy-duty 304 stainless steel. Our vacuum clamps are offered in both stainless and aluminum to fit your application.
Are LoCo's KF-40 fittings welded or milled?
Our NPT adapters, hose adapters, and flange reducers are turned from solid 304 stainless steel bar, without welds. Our elbows, tees, and crosses are welded parts.
Is KF40 the same as NW40?
Yes. KF40 and NW40 are two names for the same ISO-KF flange size. KF is the most common name; you may also see DN40 or QF40. Parts sold under any of these names connect to each other.
Can I connect KF-40 to other flange sizes?
Yes. We stock KF-40 to KF-16, KF-40 to KF-25 and KF-50 to KF-40 straight reducers, and reduced tees from KF-40 to KF-16 and KF-25.
