Products Home / Optomechanical Components / Vacuum Components / KF16-Flanged Components and AccessoriesKF16-Flanged Components and Accessories
- Quickly Connect to KF16 Vacuum Systems
- Adapters for Tubing Diameters from 6 mm to 3/4"
- Wing Nut Clamps and O-Ring Carriers
KF16CR-F
KF16 Fluorocarbon O-Ring Carrier
KF16CP
KF16 Blank Flange
KF16PC25
KF16 Flange to Ø1/4"
Double Ferrule
Compression Adapter
KF16G25E
KF16 Flange to G1/4" Straight Thread Adapter
Application Idea
Replace the double ferrule fitting on Thorlabs' Herriott Cells with the KF16G25E Vacuum Flange Adapter to enable connections to KF16 vacuum systems.
KF16C025
KF16 Flange to Ø1/4"
Compression Adapter
Please Wait
Features
- Compatible with ISO 2861 Clamped-Type Quick-Release Couplings
- Vacuum-Facing Parts Cleaned Ultrasonically
- All Parts Double-Vacuum Bagged
- To Request Other KF Flange Nominal Diameters, Please Contact Tech Support
KF flanges are ISO-standardized vacuum fittings that provide a vacuum seal by compressing a rubber O-ring between two mating surfaces. Also referred to as NW, QF, or DN flanges, KF flanges are ideal for quickly assembling vacuum systems thanks to their ease of use, maintenance, and reusability. The parts featured below have KF16 flanges. We also offer components with KF25 and KF40 flanges. Key dimensions of these KF flanges can be found by visiting the KF Flange Sizes tab. Our in-house machine shop allows us to modify or customize components with any standard KF flange. To submit a request, please contact Tech Support.
The adapters below can be used to mate British Standard Pipe Parallel (BSPP), glass or metal pipe compression fittings, or double ferrule compression fittings to KF16 vacuum components. These adapters are constructed from 304 stainless steel for high durability and low outgassing. Wing nut clamps, O-ring carriers, and blank caps are also available.
An approach for working with KF flanges is demonstrated, and tips are shared for minimizing leak rates, extending lifetimes, and recognizing when to replace O-rings.
For best performance, a very thin coating of vacuum grease should be applied to any O-ring used in a KF system. This should be done by hand while wearing gloves, leaving just enough grease to cause the O-ring to shine. The O-ring and its mating surfaces should be visually inspected before installation to ensure there is no debris which may prevent proper contact and cause a leak. O-rings should be regularly inspected to spot dry rot, cracking, tearing, or accumulation of debris from normal operation. Replace any O-ring suspected of causing a leak.
| Quick Links | |||||
|---|---|---|---|---|---|
| Flange | Description | Flange | Description | Flange | Description |
| KF16 | G1/4" Thread Adapter | KF25 | Compression Fitting Adapters | KF40 | 200 - 1200 nm Fiber Feedthrough |
| Compression Fitting Adapters | Straight, Elbow, and Tee Fittings | 0.3 - 5.5 µm Fiber Feedthrough |
|||
| Double Ferrule Compression Fitting Adapter |
O-Ring Carrier & Wing Nut Clamps |
400 - 2400 nm Fiber Feedthrough |
|||
| O-Ring Carrier & Wing Nut Clamps |
Blank Flanged Caps | O-Ring Carrier & Wing Nut Clamps |
|||
| Blank Flanged Caps | - | Blank Flanged Caps | |||
KF Flange Sizes
KF flanges are defined by ISO 2861 Clamped-Type Quick-Release Couplings. This specification details the dimensions and tolerances for the five standard KF flange sizes: 10 mm, 16 mm, 25 mm, 40 mm, and 50 mm. These sizes are the nominal bore size of the flanged pipe. The name "KF" derives from the German phrase "Klein Flansche," literally translating to "small flange"; this name was used around the time of the flange's adoption by ISO and DIN, as flanges for pipes larger than 50 mm are more appropriately handled by flanges that deform metal gaskets to create a seal, like CF flanges.
Thorlabs offers from stock 16 mm, 25 mm, and 40 mm KF components and accessories. The general dimensions of our flanges can be seen by referencing the diagram and table below. Our in-house machine shop allows us to modify or customize components with any standard KF flange. To submit a request, please contact Tech Support.
Click to Enlarge
For Thorlabs' KF Flange Measurements please see the corresponding table to the left.
| Equivalent Sizes | Thorlabs' KF Flange Measurements | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute Maximum Inner Diametera |
KF Size | DN Size | NW Size | A | B | C | |||||
| 16 mm | KF16 | DN16 | NW16 | 1.18" (30.0 mm) | 0.12" (3.0 mm) | 0.10" - 0.11" (2.5 mm - 2.8 mm) |
|||||
| 25 mm | KF25 | DN25 | NW25 | 1.58" (40.0 mm) | 0.12" (3.0 mm) | 0.10" - 0.11" (2.5 mm - 2.8 mm) |
|||||
| 40 mm | KF40 | DN40 | NW40 | 2.17" (55.0 mm) | 0.12" (3.0 mm) | 0.11" (2.7 mm) | |||||
| Posted Comments: | |
Lee Weller
(posted 2024-08-07 10:24:18.453) Is it possible to find out whether the KF16C025 fits around the TGC500C -Customer Inspired! Empty Glass Cell with Threaded Ends, 500 mm Long, Two Parallel Fill Tubes. The KF16CO25 says for pipes with OD 1/4" (0.38") and then the empty glass cell says Fill Tube Outer Diameter 0.31" (8.0 mm) is that 0.07 difference too much to fit correctly?? cdolbashian
(posted 2024-08-14 11:42:33.0) Thank you for reaching out to us with this inquiry.
It seems like you may have some dimensions confused between inner and outer diameters. The inner diameter of the KF16 connector is designed for ¼" elements while the outer diameter of TGC500C is >¼". I have contacted you directly to expound a bit more about this, inquire about your application, and make alternative product suggestions. |
Zoom
Click to Enlarge
The double ferrule fitting on Thorlabs' Herriott Cells (left) can be replaced with the KF16G25E vacuum flange adapter (right). Note that the leakage rate of the Herriott Cell is not guaranteed if the gas fitting is replaced or adjusted by the user.
- Connect KF16-Compatible Vacuum Systems to BSPP Components
- 304 Stainless Steel Construction for High Durability and Low Outgassing
- External Flats Accept 14 mm (9/16") Wrench
The KF16 Flange to G1/4" External Threading Adapter allows vacuum systems to be connected to British Standard Pipe Parallel (BSPP) components. The interior diameter of our adapter is Ø9.0 mm (Ø0.35"). The included rubber gasket is pre-installed onto the part; removing the gasket is not recommended, as it may become damaged. The exterior flats for tightening accept a 14 mm (9/16") wrench. Each flange is shipped with a protective plastic cover.
Zoom| Item # | Compatible Pipe OD |
Included O-Ring Dimensions | |||
|---|---|---|---|---|---|
| OD | ID | Thickness | Dash #a | ||
| KF16C025 | 1/4" | 0.38" | 0.24" | 0.07" | 010 |
| KF16C050 | 1/2" | 0.63" | 0.49" | 0.07" | 014 |
| KF16C075 | 3/4" | 0.88" | 0.74" | 0.07" | 018 |
- Quickly Connect Glass and Metal Pipes to KF16-Compatible Vacuum Systems
- Options for Pipe Outer Diameters (OD) of 1/4", 1/2", or 3/4"
- 304 Stainless Steel Construction for High Durability and Low Outgassing
- Internal Viton®* Fluoroelastomer O-Ring Included
KF16 flanges with compression fittings mount smooth-surfaced pipes to vacuum systems, including metal tubes, such as those used for gas lines, or glass tubes like those found on our empty glass cells or fused silica optical ports. Each fitting contains an internal Viton fluoroelastomer O-ring. When the knurled cap of the fitting is hand tightened, the O-ring compresses and forms a seal around the inserted pipe. For best results, a thin layer of vacuum grease should be applied to the internal O-ring; along with helping to create a vacuum seal, this grease allows an inserted pipe to slide along the O-ring without catching and causing damage. The knurled cap should not be overtightened, as excessive force could cause O-ring buckling, leading to leaks. The sizes of the internal O-rings are given in the table above. Each flange is shipped with a protective plastic cover.
*Viton is a registered trademark of The Chemours Company.
Zoom
Click to Enlarge
KF16PC25 adapter shown with double ferrule compression fittings. The ferrules and compressing nut are not included with the KF16PC25 or KF16PC6/M.
| Item # | Compatible Pipe OD | Thread Type |
|---|---|---|
| KF16PC25 | 1/4" | 7/16"-20 |
| KF16PC6/M | 6 mm |
- Quickly Connect KF16-Compatible Vacuum Systems to Double Ferrule Compression Fittings
- 304 Stainless Steel Construction for High Durability and Low Outgassing
- Hex Accepts 9/16" (14 mm) Wrench
This adapter allows KF16 vacuum systems to be connected to double ferrule compression fittings, making them compatible with Swagelok®-brand fittings. The image to the right shows how the KF16PC25 adapter interfaces with compression fittings; note the front ferrule, back ferrule, and nut are not included in the purchase of a double ferrule compression adapter. The KF16PC25 (KF16PC6/M) adapter accepts Ø1/4" (Ø6 mm) metal tubes and the hex on the adapter accepts 9/16" (14 mm) wrenches. Each flange is shipped with a protective plastic cover.
Zoom| Item # | Included O-Ring Dimensions | |||
|---|---|---|---|---|
| OD | ID | Thickness | Dash #a | |
| KF16CR-F | 1.15" | 0.73" | 0.21" | 314 |
- KF16CR-F Centering O-Ring Carrier for KF16 Flanges
- Holds O-Ring in Place Between KF Flanges
- Creates Vacuum Seal When Compressed Against KF Mating Surfaces
- Includes Fluorocarbon O-Ring
- KF16WNC Wing Nut Clamp for KF16 Flanges
- Secures Two KF16 Flanges Separated by an O-Ring
- Fast Hand Tightening; No Tools Required
Thorlabs offers a centering O-ring and a wing nut fastening clamp for mating KF16 flanges to a vacuum system. The angled sides of the wing nut clamp compress the O-ring between the flanges, quickly creating a vacuum seal. The wing nut clamp, which has M5 x 0.8 threads, requires only hand tightening, allowing parts to be quickly swapped in and out of a KF-flanged system.
For best performance, a very thin coating of vacuum grease should be applied to the O-ring before installation. This should be done by hand while wearing gloves, leaving just enough grease to cause the O-ring to shine. The O-ring and its mating surfaces should be visually inspected before installation to ensure there is no debris which may impede proper contact and cause a leak. O-rings should be regularly inspected to spot dry rot, cracking, tearing, or accumulation of debris from normal operation. Replace any O-ring that is suspected of causing a leak. Additionally, be aware that under vacuum pressure, the KF connection may undergo additional compression, causing the wing nut clamp to loosen. Some additional tightening may be performed, but be careful not to overtighten the clamp, as the wing nut may become difficult to remove or jammed when the system returns to atmospheric pressure. Do not remove a wing nut clamp while a system is under vacuum.
We also offer KF25 wing nut clamps and O-rings, as well as KF40 wing nut clamps and O-rings.
Zoom- 304 Stainless Steel Construction for High Durability and Low Outgassing
- Blocks Unused Vacuum Ports
Stainless steel KF flange blank caps can be used to protect a vacuum assembly that is not attached to a vacuum system, to block a port during leak testing, or to cap off a port that is not being used on a vacuum chamber body. Each cap is shipped with a protective plastic cover.
We also offer KF25 blank flange caps and KF40 blank flange caps.
KF16 Components and Accessories