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Whatever your level of vacuum we can offer an extensive range of components to connect your system.

From rough to ultra-high. Covering all main standards of connection, you can truly get your complete vacuum system from us!

Advantages at a glance:

Availability of all components at short notice

Environment-friendly and secure packaging

Compatible to your existing flanges of the same system

Highly leak-tight down to leak rates of 1 x 10-9 mbar x l/s; all components are subjected to a helium leak test

Low outgassing rates of the materials through: - choice of the right material quality, especially for vacuum apparatus - excellent cleaning methods

Documentation available for all components


The ISO-KF connection was developed by Leybold and is now the main flange type used for small fittings (up to 50 mm inner diameter) across the world in any vacuum application.

It permits rapid fitting and replacement of components in vacuum systems via its quick release clamps, hence its alternate name, the QF, Quick Flange.

Every connection consists of two symmetrical ISO-KF flanges, a cantering ring with O-ring gasket, and a clamping ring. High vacuum tight ISO-KF connections can be made without the use of tools simply by turning the wing nut of the clamping ring.

It is typically suitable for pressures down to 10-7 mbar/torr, able to withstand pressures of up to 5 bar, and can be baked up to 200 °C when metal seals are used, or 150 °C when FPM gaskets are used.

The main feature though is the speed of assembly, with no tools needed to provide a vacuum tight seal.


For larger diameters, you will typically find ISO-K and ISO-F fittings.

  • ISO-K fittings are often preferred as the clamps can be positioned at any point around the flange, rather than at fixed bolting points.
  • ISO-F flanges would be found when the flange is also being used as a structural element given their increased strength.

These flange types range from inner diameters of in sizes from DN 63 up to DN 630 (so tube diameters of 70 to 650mm). Since the centering ring can be firmly inserted into the centering groove of the flange, even horizontal connections are quickly and easily fitted.

With this type of connection, pressures down to 10-9 mbar can be achieved when using metal gaskets. Again, bakeouts of up to 200 °C can be achieved when using metal flanges, and 150 °C when using FPM.


The CF flange connection consists of two geometrically identical flanges with a flat gasket made of OFHC copper, bolts and nuts and washers.

CF components are made of selected, corrosion resistant types of stainless steel. This type of sealing is very strong, and is why CF flanges are used when needing to reach UHV pressures, which also require baking (suitable with all metal sealing).

All components are welded inside to prevent right from the beginning any cracks or pocket holes which might constitute a so-called virtual leak.

Available in sizes from DN 16 CF to DN 250 CF (ID 16 mm to 250 mm) these are often found on gauges, ion pumps and turbomolecular pumps used to reach ultra-high vacuum pressures.


The need to control inside and transfer power to vacuum is handled via feedthroughs.

We have a range of standard and high current feedthroughs. We then have a range of rotary, liquid, rotary/linear to transfer force/objects into the vacuum system.

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