KF to NPT adapters connect a threaded pipe port to a KF flange. They bring gauges, valves, pumps and other threaded components into a KF vacuum system. LoCo Science carries male (MNPT) and female (FNPT) adapters in KF-16 (1/8" to 3/4"), KF-25 (1/8" to 1"), KF-40 (1/8" to 2") and KF-50 (1.25" to 2"), all turned from solid 304 stainless steel bar with no welds.
Which KF to NPT adapter do I need?
- Find your flange size: Measure the outside diameter of your flange and compare it to our KF flange size chart, or check the size marked on your equipment.
- Screw into a threaded port: Use a male (MNPT) adapter.
- Accept a threaded fitting or pipe: Use a female (FNPT) adapter.
- Match the thread size: Choose the NPT size of your port or fitting.
- Connect the flange side: One clamp and centering ring set of the same flange size.
Frequently asked questions
How do I seal the threads on a KF to NPT adapter?
Wrap the male threads with PTFE thread tape, or use an anaerobic pipe-thread sealant for a permanent joint. For threads 1" and larger, a liquid pipe-thread sealant is the better choice. Avoid plumber's pipe dope in vacuum lines.
Are LoCo's KF to NPT adapters welded?
No. They are turned from solid 304 stainless steel bar, without welds.
What NPT sizes are available?
KF-16: 1/8" to 3/4". KF-25: 1/8" to 1". KF-40: 1/8" to 2". KF-50: 1.25" to 2". All in male and female.
