DN75CF (4.625″ OD) 304L SS Standard ConFlat® (CF) UHV Flanges

TFM DN75CF (4.625″ OD) 304L SS Standard Flanges for UHV Applications

The TFM DN75CF flange, with an outer diameter of 4.625 inches, is a standard choice for high vacuum and ultra-high vacuum (UHV) applications. This flange system is well-supported by a variety of gauges, instruments, accessories, and feedthroughs, making it a versatile component in vacuum technology.

Overview of Blank (Blind) Flanges

A blank (or blind) flange serves as a solid, disc-shaped fitting used in vacuum systems to seal off unused sections of tubing or ports in vacuum chambers. These flanges can be precisely machined to create custom fittings tailored to specific requirements.

Sealing Mechanism of TFM Flanges

TFM flanges utilize a knife-edge sealing mechanism. The knife-edge is machined just below the flat surface of the flange. When the bolts of a flange pair are tightened, the knife-edges carve annular grooves into a soft metal gasket. This process allows the extruded metal to fill any surface imperfections and machining marks on the flange, resulting in a leak-tight seal. The TFM seal operates efficiently from 760 torr (103 mbar) down to < 1 x 10^-13 Torr (< 1.3 x 10^-13 mbar), maintaining performance within a temperature range of -196°C to 450°C, depending on the materials used.

Flange Size Nomenclature

In North America, TFM flange sizes, such as the DN75CF, are typically designated by their outer diameter (O.D.). Conversely, in Europe and much of Asia, the nominal internal diameter (I.D.) of the largest tube that can be welded to a bored flange is often used as the reference.

Versions of TFM Flanges

TFM flanges are available in several configurations to meet varying application needs:

Fixed Flange

The fixed flange is designed as a single piece where the bolt-hole orientation remains constant relative to the fitting. This design is optimal for setups requiring specific alignment.

Rotatable Flange

The rotatable flange consists of two components: an inner weld ring and an outer bolt ring. This arrangement allows the bolt ring to rotate around the inner weld ring, facilitating easier alignment of the bolt holes during installation.

Both fixed and rotatable TFM flanges can be customized with your choice of through (clearance) holes or tapped holes, offering flexibility for different applications.

Applications of TFM DN75CF Flanges

Due to their robust sealing capabilities and adaptability, TFM DN75CF flanges are widely utilized in industries that require high or ultra-high vacuum conditions. Their reliability is essential in sectors such as semiconductor manufacturing, materials research, and scientific instrumentation, where maintaining vacuum integrity is critical for optimal performance.

Ordering Table