ASA ANSI flanges were originally used for steam pipes but have now been adapted to vacuum. Diffusion pumps, roots blowers, cryopumps and large rotary piston pumps are some examples of the ASA flange uses. Using O-Rings with Viton, Buna or Red Silicone they are capable of achieving pressures as low as 1x10-8 Torr. We have a complete line of ASA flanges, adapters, O-rings and bolt kits to fit your most demanding needs. For related products see below. 

Straight Tube Reducer, ASA 3" to ASA 1" Vacuum Fittings, ASA Flange Sizes 3" to 1", Stainless Steel 

ASA Flange Size: 3" to 1"

Common Dimensions:

A = Tube OD 2.5 in.

B = Reducer Flange OD 5 in.

C = Main Flange OD 6 in. 

D = Length 5 in.