KF Flanges
ANCORP’s KF (QF) flanges are available in a variety of designs and materials for easy integration into high vacuum systems and components. Available flange types include bored weld flanges, blank flanges, and unbored stub flanges. All KF flanges are manufactured to ISO specifications to ensure 100% compatibility with other vacuum flange manufacturers’ components. ANCORP offers KF flanges in 304 stainless steel and 316 stainless steel.
KF Flanges (ISO-QF Quick Flanges)
KF flanges, also called QF or NW flanges, are used to form high vacuum connections in 1/2″ (QF10) to 2″ (QF50) diameter vacuum system tubing. KF flanges are sexless, infinitely rotatable, and fastened with quick clamps that compress an elastomer O-Ring held in a centering ring between two flange faces to create a high vacuum seal.
ISO KF flange sizes reference the inner diameter in millimeters of vacuum tubing. A KF flange size chart can be found below.
KF Flange Size Chart
| ISO Size | Tubing I.D. (mm) | Flange Reference | Tubing O.D. (in.) |
|---|---|---|---|
| NW10 | 10 | QF10 | 0.50 |
| NW16 | 16 | QF16 | 0.75 |
| NW25 | 25 | QF25 | 1.00 |
| NW40 | 40 | QF40 | 1.50 |
| NW50 | 50 | QF50 | 2.00 |
KF Flange Types
Blank flanges are manufactured with no weld prep and no tubing bore. They are commonly used to close unused ports or they are altered by customers with their own machining capability for special use.
Weld flanges are manufactured with a weld prep and tubing bore for immediate installation on your vacuum system with no additional alteration. We offer weld flanges in four different designs to meet your specific requirements:
- QF Bored Weld Flanges – have a standard weld prep. QF bored weld flanges
- QF Socket Weld Flanges – designed with a tube counterbore for internal welds.
- QF Weld Ring Flanges – similar to socket weld flanges but have a thinner cross-sectional profile
- Stub Weld Flanges – designed for butt welds. QF stub weld flanges are available.
QF Unbored stub flanges are manufactured with no weld prep and no tubing bore. They are commonly altered by customers with their own custom machining capability for special use.