MDC’s Large-Flange™ ISO LF components are an economical system of reusable and interfacing stainless steel vacuum fittings for tube sizes ranging from 2-1/2″ through 20″ diameters. Large-Flange™ ISO LF flanges pick up where the Kwik-Flange™ ISO KF system leaves off. These flanges can operate in high vacuum environments to pressures in the 1×10-8 Torr range. The Large-Flange™ ISO LF flange system is ideally suited for applications requiring rapid and frequent assembly and disassembly. MDC ISO LF flanges comply with all ISO specifications for vacuum mounting hardware and are compatible with most third party ISO LF flanges and components.

The MDC Large-Flange™ ISO LF family of modular building-block components includes all of the commonly used standard hardware and fittings. Virtually all standard MDC feedthroughs and accessories are available for use with Large-Flange™ ISO LF flanges. Reducer flanges are available to connect different size ISO components. This section includes ISO KF and ISO LF reducer flanges for KF to KF, KF to LF and LF to LF flange Large-Flange™ ISO LF flange combinations. Hybrid adapters are available to connect ISO LF components to non ISO vacuum fittings and mounts. Some of these include Del-Seal™ CF metal seal flanges, ANSI ASA flanges, Swagelok? compression tube fittings and VCR? metal gasket tube fittings and national pipe thread fittings. For more details and information on hybrid adapters please reference Section 1.5 in this catalog.

MDC Large-Flange™ ISO LF flanges are available in nine standard maximum tube sizes including 2-1/2″, 3″, 4″, 6″, 8″, 10″, 12-3/4″, 16″ and 20″ diameters. Each of these basic flanges are also offered in blanked formats which are suitable for custom modification or to blank-off unused chamber ports. Typically, U.S. tube sizes are specified in inches and identified by their outside diameters. MDC standard ISO LF flange size designations are as follows…
L250 for 2.50″, L300 for 3.00″, L400 for 4.00″, L600 for 6.00″, L800 for 8.00″, L1000 for 10.0″, L1200 for 12.75″, L1600 for 16.0″ and L2000 for 20.0″ tube diameters.

In general, MDC components compare with international components using an inch-to millimeter ratio. U.S. sizes refer to a tube’s outside diameter, whereas international sizes refer to a tube’s inside diameter. The chart on the right side gives a quick comparison between inch and metric ISO flange sizes.