ASA HV Flanges–Fixed Flat

ASA HV Flanges – Fixed Flat: Mating Interfaces for Secure O-Ring Sealing in ASA High-Vacuum Systems

ASA HV Flanges – Fixed Flat, manufactured by TFM, are key components in high-vacuum (HV) systems that use ASA-standard sexed vacuum seals. These flanges feature a smooth sealing face and are designed to mate with grooved ASA flanges that hold elastomeric o-rings. Together, they form a dependable vacuum seal via mechanical compression, ensuring leak-tight performance at pressures down to ~10⁻⁷ torr.

Each fixed flat flange is fabricated from 304L stainless steel, offering excellent corrosion resistance, high mechanical strength, and compatibility with vacuum welding or brazing processes. The non-rotatable (fixed) design provides permanent alignment, making it well-suited for applications that require stability and repeatable bolt positioning.

Key Features of ASA HV Flanges – Fixed Flat:

• Smooth Sealing Surface
  Designed to compress against a grooved ASA flange with an o-ring, forming a reliable sexed seal common to ASA systems.

• Fixed Configuration for Permanent Installations
  The flange is welded or brazed in place, eliminating the need for rotational adjustment and providing robust mechanical rigidity.

• 304L Stainless Steel Build
  Suitable for vacuum environments with exposure to corrosive agents or temperature variation; ideal for research and industrial HV systems.

• Nominal Pipe-Based Sizing
  Flanges are sized by the nominal inner diameter (I.D.) of the pipe in inches. Common sizes include:
  1″, 1.5″, 2″, 3″, 4″, 6″, 8″, and 10″

• Large Outer Diameter and Bolt Circle
  ASA flanges have generously spaced bolt holes around the perimeter, allowing for secure and uniform clamping.

• Application Range (based on o-ring material)
  – Temperature: ~0°C to 120–180°C
  – Pressure: Atmosphere to ~10⁻⁷ torr

Typical Applications:

• Vacuum chamber ports with fixed hardware

• Pump and component connections requiring flat sealing faces

• Modular systems using ASA-standard interfaces

• Retrofitted systems requiring grooved-to-flat sealing

• Process vacuum systems in semiconductor, aerospace, and energy industries

TFM also provides grooved ASA flanges, rotatable versions, FKM and Buna-N o-rings, as well as bolt kits and blank-off flanges, enabling full customization of your ASA HV assembly.

In summary, ASA HV Flanges – Fixed Flat offer a stable and durable solution for o-ring-based high-vacuum sealing. Their permanent mounting design, smooth sealing face, and stainless steel construction make them an essential component in any ASA-configured vacuum infrastructure.