Description
These blank non-rotatable flanges are for sealing off ports, for drilling custom interfaces, feedthrus, or other accessories, and for modifications of vacuum equipment. These reliable, knife-edge flanges are the vacuum industry standard for ultra-high vacuum applications. They utilize flat OFHC copper gaskets for vacuum sealing below 10-13 torr at temperature ranges from -196 degrees C to 500 degrees C. Manufactured from Type 304 stainless steel, all flanges will perfectly mate to other Conflat flanges of the same O.D.
Other flange types and sizes are available on request. Custom drilling, modifications, welding and fabrication are also available from our machine shop. Call SIS with your requirements or send drawings for a quotation.
Blank Non-Tapped Flanges | |||||||||||
Part No. | OD (in) | Thickness (in) | # Bolts | Bolt Diameter (in) | Bolt Cir Diameter (in) | Cu Gask | Quantity In Stock |
Price EA |
Order | ||
---|---|---|---|---|---|---|---|---|---|---|---|
133X000 | Blank Non-Tapped Flange | ||||||||||
1.33 | 0.28 | 6 | 0.172 | 0.060 | CG-300 | DISCONTINUED | --- | --- | |||
212X000 | Blank Non-Tapped Flange | ||||||||||
2.12 | 0.470 | 4 | 0.265 | 1.625 | CG-400 | DISCONTINUED | --- | --- | |||
275X000 | Blank Non-Tapped Flange | ||||||||||
2.73 | 0.500 | 6 | 0.265 | 2.132 | CG-500 | DISCONTINUED | --- | --- | |||
450X000 | Blank Non-Tapped Flange | ||||||||||
4.47 | 0.680 | 8 | 0.332 | 3.628 | CG-1000 | DISCONTINUED | --- | --- | |||
600X000 | Blank Non-Tapped Flange | ||||||||||
5.97 | 0.780 | 16 | 0.332 | 5.128 | CG-1500 | DISCONTINUED | --- | --- | |||
675X000 | Blank Non-Tapped Flange | ||||||||||
6.75 | 0.840 | 18 | 0.332 | 5.969 | CG-1800 | DISCONTINUED | --- | --- | |||
Blank Tapped Flanges | |||||||||||
Part No. | OD (in) | Thickness (in) | # Bolts | Bolt Diameter (in) | Bolt Cir Diameter (in) | Cu Gask | Bolts | Quantity In Stock |
Price EA |
Order | |
275X000T | Blank Tapped Flanges | ||||||||||
2.73 | 0.500 | 6 | 0.265 | 2.312 | CG-500 | 1/4-28 | DISCONTINUED | --- | --- | ||
* Call for availability. | |||||||||||
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Socket Head Cap Screws - Flange Hardware
Screws, Nuts, WashersCopper Gaskets for Vacuum Flanges
The below listed vacuum flange copper gaskets are made from OFHC copper.

The below listed vacuum flange copper gaskets are made from OFHC copper.

Copper used.

All gaskets are .080" thick.

The following copper and gold plated copper gaskets are available
for the vacuum flanges on Thermo/Finnigan mass spectrometers.

QF to QF Reducers, Aluminum fittings

Screws, Nuts, Washers

Stainless union for connection NW flanges to Varian type conflat flanges.

S.I.S. carries copper and gold plated copper gaskets for the Varian Saturn.