Bolt Kit for ASA 4.5 / ANSI 1 and ASA 5.0 / ANSI 1.5 Smooth or Grooved Flanges, Includes Four Stainless Steel 9/16-12 x 2 in. Long Bolts & Washers.

These bolt kits are designed to bolt together ASA 4.5 or ASA 5.0 (ANSI 1 or ANSI 1.5) flanges. The kits consist of four 9/16-12 x 2" long bolts and nuts, flat and lock washers, all made of stainless steel.

These kits work with both grooved or non-grooved flanges. Grooved flanges require an additional elastomer rubber O-Ring. We recommend using thread anti-seize lubricant on all vacuum fitting bolts.

Bolt Kit Includes:

4 Bolts, 9/16-12 Thread x 2 inch Long
4 Nuts, 9/16-12
4 Lock Washers
8 Flat Washers

ASA flanges are available with a smooth or grooved face, rotatable or non-rotatable, bored or non-bored, and are named for the outer diameter of the flange, from 4.25 to 19 inches. The ANSI name for the same flange size corresponds to the nominal tubing size that can be welded to it, and ranges from 1 to 12 inches in diameter.

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 vacuum pumps where these flanges are used. When sealed together with O-rings made of Viton, Buna or Silicone, they are capable of achieving vacuum pressures as low as 1x10^-8 Torr. We have a complete line of ASA flanges, O-rings, and bolt sets to fit your most demanding needs.