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Quick-Clamp High-Vacuum Fittings for Stainless Steel Tubing
- For Use With:
Fittings with Gasket End: Air, Argon, Helium, Nitrogen
All Other Fittings: Air - Temperature Range: 0° to 300° F
- Tubing: Use with 304/304L or 316/316L stainless steel
- Specifications Met: ISO 2861
Instead of a gasket, these fittings have a special ring that is designed for high-vacuum applications, such as vacuum coating and heat treating, leak testing, and analyzing gases. Also known as KF, QF, and NW fittings, they are the most common type of connection in high-vacuum systems. Connect with a clamp and another quick-clamp fitting for fast, easy access to your line. To use fittings in pressure applications, use a pressure-rated ring (sold separately).
304 stainless steel fittings have very good corrosion resistance.
Note: To complete a connection, you’ll need two quick-clamp fittings, a ring, and a clamp (all sold separately).
For technical drawings and 3-D models, click on a part number.
Fittings with flanged end connect to pumps, valves or gauges that have flanged connections. Also known as conflat, CF, or UHV fittings, they have a higher vacuum rating than quick-clamp fittings, so these adapters allow you to connect between different levels of vacuum within a system. A copper gasket (sold separately) creates a tight seal between the two flanges.
Quick-Clamp Tube Connection | Flanged Tube Connection | Bolt Hole | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | For Bolt Dia. | Bolts Included | Max. Vacuum | Max. Pressure | Each | |
| 3/4" | 1.18" | 16 | ISO-KF | 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | 1/4" | No | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 0000000 |
| 1" | 1.57" | 25 | ISO-KF | 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | 5/32" | No | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | 1/4" | No | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | 5/16" | No | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | 5/16" | No | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
Clamps tighten by hand. Spring-loaded clamps are also known as toggle clamps.
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Material | Max. Vacuum | Lanyard Length | Each | |
with Wing Nut | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1/2", 3/4" | 1.18" | 10, 16 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 00000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
Spring Loaded | ||||||||
| 1/2", 3/4" | 1.18" | 10, 16 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
Spring Loaded with Lanyard | ||||||||
| 3/4" | 1.18" | 16 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
Use these rings with quick-clamp high-vacuum fittings. They consist of a stainless steel inner ring covered by a fluoroelastomer O-ring.
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Inner Ring Material | Max. Vacuum | Max. Pressure | Each | |
Rings | ||||||||
|---|---|---|---|---|---|---|---|---|
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 0000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 0000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 0000000 | 00000 |
Rings with Stainless Steel Screen | ||||||||
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
Rings with Aluminum Outer Ring | ||||||||
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 100 psi @ 72° F | 0000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 75 psi @ 72° F | 0000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 50 psi @ 72° F | 0000000 | 00000 |
Hose absorbs moderate vibration
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Material | Max. Vacuum | Bend Radius | Flexibility | Each | |
3 3/16" Lg. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Rigid | 0000000 | 000000 |
4 3/16" Lg. | |||||||||
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Rigid | 0000000 | 00000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Rigid | 0000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Rigid | 0000000 | 000000 |
12" Lg. | |||||||||
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 1 5/8" | Flexible | 00000000 | 000000 |
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 1 3/8" | Flexible | 00000000 | 000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 2 1/2" | Flexible | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
24" Lg. | |||||||||
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 1 5/8" | Flexible | 00000000 | 000000 |
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 1 3/8" | Flexible | 00000000 | 000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 2 1/2" | Flexible | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
39" Lg. | |||||||||
| 3/4" | 1.18" | 16 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 1 5/8" | Flexible | 00000000 | 000000 |
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 1 3/8" | Flexible | 00000000 | 000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 2 1/2" | Flexible | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
Ultra-High-Vacuum Flanges and Fittings for Stainless Steel Tubing
- For Use With: Air
- Temperature Range:
Flanges: -300° to 800° F
Gaskets: Not Rated - Tubing: Use with 304/304L and 316/316L stainless steel
- Specifications Met:
Flanges: ASTM A240, ASTM E45, ASTM E12
Gaskets: ASTM B152-179, ASTM F68
Create access points in ultra-high-vacuum lines or chambers by bolting two same-size flanges together with a copper gasket (sold separately) between them. The flanges’ sharp edges dig into the copper gasket and form an extremely tight seal, which means they handle higher vacuum pressures than other high-vacuum fittings with rubber gaskets. Also known as CF, Conflat, and UHV fittings, use them in vacuum coating, heat treating, and drying applications, as well as for leak testing and analyzing gases. They’re stainless steel so they resist rusting.
Fittings with a rotating flange turn so you can easily match up the bolt holes with another flange that may be misaligned.
Butt-weld flanges provide a flush connection for smooth flow through your line.
Socket-connect flanges are easier to weld than butt-weld flanges because they don’t need to align perfectly to tubing; insert the tubing into the socket end and weld together.
Caps are also known as blind flanges.
Bolt kits are required to make a complete connection.
For technical drawings and 3-D models, click on a part number.
Bolt Hole | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | Bolts Included | No. of Bolt Kits Required | Lg. | Max. Vacuum | Material | Appearance | Each | |
Fixed × Rotating | ||||||||||||||
| 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 2 | 3" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 2 | 4 15/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 2 | 6 11/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 4 | 8 5/8" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
Bolt Hole | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | Bolts Included | No. of Bolt Kits Required | Max. Vacuum | Material | Appearance | Each | |
Rotating | |||||||||||||
| 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 2 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 0000000 |
| 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 2 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 2 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 4 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
Butt-Weld Tube Connection | Flanged Tube Connection | Bolt Hole | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Wall Thick. | For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | Bolts Included | No. of Bolt Kits Required | Lg. | Max. Vacuum | Material | Appearance | Each | |
Fixed | ||||||||||||||||
| 3/4" | 0.049" | 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 1 | 1 1/2" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 3/4" | 0.06" | 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 1 | 9/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 1 1/2" | 0.065" | 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 1 | 2 15/32" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 2 1/2" | 0.065" | 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 1 | 3 3/8" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 4" | 0.083" | 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 4 | 4 5/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
Rotating | ||||||||||||||||
| 3/4" | 0.06" | 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 1 | 9/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
Socket-Connect Tube Connection | Flanged Tube Connection | Bolt Hole | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Socket Dp. | For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | Bolts Included | No. of Bolt Kits Required | Lg. | Max. Vacuum | Material | Appearance | Each | |
Fixed | ||||||||||||||||
| 3/4" | 7/64" | 3/4" | 1 21/64" | 16 | CF | 11/16" | 3/16" | 6 | No | 1 | 5/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 1 1/2" | 13/64" | 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 1 | 1/2" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 2 1/2" | 3/8" | 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 1 | 11/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 4" | 7/16" | 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 2 | 25/32" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
Rotating | ||||||||||||||||
| 3/4" | 1/8" | 3/4" | 1 21/64" | 16 | CF | 11/16" | 3/16" | 6 | No | 1 | 5/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 1 1/2" | 13/64" | 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 1 | 1/2" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 2 1/2" | 3/8" | 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 1 | 11/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 4" | 7/16" | 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 2 | 25/32" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
Bolt Hole | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | Bolts Included | No. of Bolt Kits Required | Max. Vacuum | Material | Appearance | Each | |
Fixed × Rotating × Rotating | |||||||||||||
| 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 3 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 0000000 |
| 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 3 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 3 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 6 | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
Bolt Hole | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Bolt Circle Dia. | Dia. | No. of | Bolts Included | No. of Bolt Kits Required | Lg. | Max. Vacuum | Material | Appearance | Each | |
Fixed | ||||||||||||||
| 3/4" | 1 21/64" | 16 | CF | 1 1/16" | 11/64" | 6 | No | 1 | 5/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 000000 |
| 1 1/2" | 2 3/4" | 40 | CF | 2 5/16" | 17/64" | 6 | No | 1 | 1/2" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 2 1/2" | 4 1/2" | 63 | CF | 3 5/8" | 21/64" | 8 | No | 1 | 11/16" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 00000 |
| 4" | 6" | 100 | CF | 5 1/8" | 21/64" | 16 | No | 2 | 25/32" | 1 × 10 -13 torr @72° F | 304 Stainless Steel | Polished | 0000000 | 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 |