Flanges (Flat, Groove and Choke)

The wide variety of flanges detailed here are available as standard on the majority of GIW products. The flanges are based on the major international flange interface specifications, and GIW also have many of the more obscure standards and customer specific flanges on record. Standard flanges are available in Brass or Aluminium and other materials on request. Certain designs are available from stock to provide a minimum delivery lead-time.

GIW offer technical support at the design stage to ensure the most suitable flange is chosen for every application.

All flanges are manufactured to the highest quality standards

Global Invacom Waveguide (GIW) is an ISO9001:2008.approved company

Please download the GIW Flange Brochure from the products main menu.

Flange Finder

To find a particular flange, start by clicking the waveguide size below, and refine the seach on the following page. These are the more common flanges - GIW has a large library of flange standards on record.

More information on waveguide sizes
More information on flange types


The flange and waveguide materials should match i.e. aluminium flanges for aluminium waveguide or brass flanges for copper or brass waveguide.

Choke flanges
A choke flange must be used together with a plain flange - it is usually used for very high powers to improve the apparent contact of the joint, but as the choke is frequency sensitive, the match seen at the top and bottom of the band is generally worse than a plain / plain combination. .An alternative to a choke / plain joint for high powers is a plain / plain joint together with a high power shim. The shims are generally crushable (single use) or have sprung fingers to ensure good contact. Choke flanges are more sensitive to misalignment so the correct bolts should be used - fixing kits can be supplied to suit.