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Ultra-High-Vacuum Hose with Flanges
Often found in semiconductor manufacturing and other demanding industrial applications, this hose handles nearly perfect vacuum. Sharp edges on the flanges dig into a copper gasket (sold separately) as you bolt the flanges together, creating a tighter seal than fittings with a rubber gasket. This allows the hose to maintain the ultra-high vacuum necessary for vacuum coating, heat treating, leak testing, and analyzing gases. The flanges are commonly referred to as ConFlat (CF) and UHV fittings. Thanks to its ribbed interior, this hose is flexible enough to connect misaligned components. That's why it's also called a bellows. The ribbing reduces vibration between components, such as vacuum pumps, valves, and chambers. Both the hose and flanges are made of stainless steel, so they resist rusting.
One of the flanges rotates, so you can easily match up the bolt holes with another flange. Make sure your mating flanges are the same size as these flanges.
Bolt kits are required to make a complete connection.
For technical drawings and 3-D models, click on a part number.


- Temperature Range: -200° to 900° F
- Maximum Vacuum: 10 -13 torr @ 72° F
- Material: 321 Stainless Steel
- Fitting Material: 304 Stainless Steel
Bolt Hole | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | ID | OD | Wall Thickness | Bend Radius | Bolt Circle Dia. | Dia. | No. of | Each | |
Fixed Flange × Rotating Flange | ||||||||||||
4" Lg. | ||||||||||||
3/4" | 1 21/64" | 16 | CF | 5/8" | 1 1/8" | 0.008" | 1 1/4" | 1 1/16" | 3/16" | 6 | 0000000 | 0000000 |
1 1/2" | 2 3/4" | 40 | CF | 1 1/2" | 2 3/16" | 0.008" | 2 1/4" | 2 5/16" | 17/64" | 6 | 00000000 | 000000 |
6" Lg. | ||||||||||||
2 1/2" | 4 1/2" | 63 | CF | 2 3/8" | 3 1/4" | 0.008" | 4 1/4" | 3 5/8" | 21/64" | 8 | 00000000 | 000000 |
4" | 6" | 100 | CF | 3 7/8" | 4 7/8" | 0.008" | 6" | 5 1/8" | 21/64" | 16 | 00000000 | 000000 |
12" Lg. | ||||||||||||
3/4" | 1 21/64" | 16 | CF | 5/8" | 1 1/8" | 0.008" | 1 1/4" | 1 1/16" | 3/16" | 6 | 00000000 | 000000 |
1 1/2" | 2 3/4" | 40 | CF | 1 1/2" | 2 3/16" | 0.008" | 2 1/4" | 2 5/16" | 17/64" | 6 | 00000000 | 000000 |
2 1/2" | 4 1/2" | 63 | CF | 2 3/8" | 3 1/4" | 0.008" | 4 1/4" | 3 5/8" | 21/64" | 8 | 00000000 | 000000 |
4" | 6" | 100 | CF | 3 7/8" | 4 7/8" | 0.008" | 6" | 5 1/8" | 21/64" | 16 | 00000000 | 000000 |
24" Lg. | ||||||||||||
3/4" | 1 21/64" | 16 | CF | 5/8" | 1 1/8" | 0.008" | 1 1/4" | 1 1/16" | 3/16" | 6 | 00000000 | 000000 |
1 1/2" | 2 3/4" | 40 | CF | 1 1/2" | 2 3/16" | 0.008" | 2 1/4" | 2 5/16" | 17/64" | 6 | 00000000 | 000000 |
2 1/2" | 4 1/2" | 63 | CF | 2 3/8" | 3 1/4" | 0.008" | 4 1/4" | 3 5/8" | 21/64" | 8 | 00000000 | 000000 |
4" | 6" | 100 | CF | 3 7/8" | 4 7/8" | 0.008" | 6" | 5 1/8" | 21/64" | 16 | 00000000 | 000000 |
36" Lg. | ||||||||||||
3/4" | 1 21/64" | 16 | CF | 5/8" | 1 1/8" | 0.008" | 1 1/4" | 1 1/16" | 3/16" | 6 | 00000000 | 000000 |
1 1/2" | 2 3/4" | 40 | CF | 1 1/2" | 2 3/16" | 0.008" | 2 1/4" | 2 5/16" | 17/64" | 6 | 00000000 | 000000 |
2 1/2" | 4 1/2" | 63 | CF | 2 3/8" | 3 1/4" | 0.008" | 4 1/4" | 3 5/8" | 21/64" | 8 | 00000000 | 000000 |
4" | 6" | 100 | CF | 3 7/8" | 4 7/8" | 0.008" | 6" | 5 1/8" | 21/64" | 16 | 00000000 | 000000 |

For Flange OD | For High-Vacuum Flange Size | Bolt Dia. | Thread Size | No. of Bolts Included | No. of Nuts Included | No. of Washers Included | Bolt Material | Each | |
1 21/64" | 16 | 0.164" | 8-32 | 6 | 6 | 12 | 18-8 Stainless Steel | 0000000 | 00000 |
2 3/4" | 40 | 1/4" | 1/4"-28 | 6 | 6 | 12 | 18-8 Stainless Steel | 0000000 | 00000 |
4 1/2" | 63 | 5/16" | 5/16"-24 | 8 | 8 | 16 | 18-8 Stainless Steel | 0000000 | 00000 |
6" | 100 | 5/16" | 5/16"-24 | 16 | 16 | 32 | 18-8 Stainless Steel | 0000000 | 00000 |