Compare Model Drawings, CAD & Specs Flange Size Availability Price
Rotatable Bolt Ring, ISO-MF Size NW63 Vacuum Flange, Aluminum
Rotatable Bolt Ring, ISO-MF Size NW80 Vacuum Flange, Aluminum
4 Weeks
4 Weeks
Rotatable Bolt Ring, ISO-MF Size NW100 Vacuum Flange, Aluminum
Rotatable Bolt Ring, ISO-MF Size NW160 Vacuum Flange, Aluminum
4 Weeks
4 Weeks
Rotatable Bolt Ring, ISO-MF Size NW200 Vacuum Flange, Aluminum
Rotatable Bolt Ring, ISO-MF Size NW250 Vacuum Flange, Aluminum
5 Weeks
5 Weeks
Rotatable Bolt Ring, ISO-MF Size NW320 Vacuum Flange, Aluminum
Rotatable Bolt Ring, ISO-MF Size NW400 Vacuum Flange, Aluminum
Rotatable Bolt Ring, ISO-MF Size NW500 Vacuum Flange, Aluminum


  • Component Type
    Rotatable Bolt Ring
  • Series
    Series 76
  • Flange Type
  • Material
  • Retaining Ring
    Stainless Steel


ISO Universal Vacuum Flange System

Series 76 ISO flange components are a vacuum flanging system for 63 mm to 1000 mm fittings. The dimension criteria are based on requirements established by the International Standards Organization (ISO). There are two flange styles in the ISO-Universal system: ISO-MF (multi-fastener flange) and ISO-BF (bolted flange). These flanges are also referred to as ISO-LF (large flange), ISO-K, ISO Universal, or as plain "ISO" flanges.

There are several advantages in the use of ISO components. One advantage is that the flange is “sexless.” The seal is on a symmetrical centering ring that interfaces with two identical flanges. In addition, ISO Universal flanges are more compact than ASA flanges, which were designed for pressure and are unnecessarily massive for vacuum use. Since these flanges are an ISO standard, they can be used with components from other manufacturers.

Series 76 flanges and components are made of type 304 stainless steel. Centering ring and seal assemblies are offered with an aluminum centering ring and spacer ring, or with a stainless centering ring and an aluminum spacer ring. Rotatable bolt rings and clamps are made of aluminum alloy. Retaining rings are made of steel. Flange seal surfaces are carefully machined and inspected for defects. They are cleaned and packaged to remain clean and protected in shipping. The Series 76 ISO-Universal flange components can be connected in various ways.

Rotatable Bolt Rings

You can join an ISO-BF bolted flange to an ISO-MF an ISO-MF Multi-fastener flange by using a rotatable bolt ring on the ISO-MF flange. In attaching a rotatable bolt ring to an MF flange, the ring is first passed over the flange with the larger bore of the ring facing outward from the open port. The split retaining ring is then snapped into the groove on the periphery of the ISO-MF flange. Then the bolt ring is pulled forward into position. The vacuum flanges are then joined using nuts and bolts.

ISO-MF Vacuum Flange Applications

The Series 76 ISO-MF vacuum flange component system is used in a variety of industries from process manufacturing to semiconductor fabrication to thin film deposition. Some uses in vacuum systems are:

  1. Roughing and foreline plumbing for large vacuum systems
  2. High vacuum, high conductance, interconnections
  3. Modular systems which will be modified frequently
  4. Experimental systems in research laboratories

ISO-Universal flange components using elastomer seals are primarily designed for use at subatmospheric pressure. When elastomer seals are used without baking, typical limiting pressures may be around 10-6 Torr. Baked systems using Viton can be used to 10-8 Torr.

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