The MDC Large-Flange™ ISO LF system provides a cost-effective, reusable solution for high vacuum applications involving large-diameter tubing ranging from 2.5" to 20" (63.5 mm to 508 mm). These Type 304 stainless steel vacuum fittings are engineered for high vacuum performance, operating reliably at pressures as low as 1x10⁻⁸ Torr (1.33x10⁻⁶ Pa) and bakeable to 150°C.

The ISO LF flange system builds upon the Kwik-Flange™ KF line, offering greater size compatibility while maintaining compliance with ISO standards and third-party component compatibility. The primary sealing mechanism uses double-claw clamps to compress an elastomer gasket mounted on an aluminum centering ring between mating flanges—ensuring a uniform seal when bolts are tightened in a crisscross pattern.

Additional mounting options include single claw clamps, bolted rotatable or nonrotatable rings, and MDC’s proprietary band-clamp system, which brings the ease of hinged clamps to ISO LF systems for tube sizes from 2.5" to 8" (63.5 mm to 203.2 mm). The Large-Flange™ family includes all standard hardware and can be configured with MDC’s extensive selection of feedthroughs, blank-offs, and accessories.

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.

Industry Applications

Large-Flange™ ISO LF components are ideal for vacuum chambers, beamlines, large-scale analytical instruments, and industrial vacuum processing. Their large diameter, modular format, and reliable sealing make them suitable for applications in semiconductor fabrication, fusion research, space simulation, cryogenics, and thin-film deposition. With multiple fastening styles and reusable construction, they enable fast setup and flexible integration—meeting the evolving needs of high-throughput and high-performance vacuum systems.