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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 claw-clamp end are often used to connect high-vacuum components with large-diameter connections, such as coating or heat-treating equipment, to components with smaller connections such as gauges, filters, or pumps. Also known as ISO-K fittings, they connect with four claw clamps and a ring (sold separately).
Quick-Clamp Tube Connection | Claw-Clamp Tube Connection | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 | Max. Vacuum | Max. Pressure | Each | |
| 1" | 1.57" | 25 | ISO-KF | 2 1/2" | 3.74" | 63 | ISO-K | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 0000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 2 1/2" | 3.74" | 63 | ISO-K | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 3" | 4.33" | 80 | ISO-K | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 1 1/2" | 2.16" | 40 | ISO-KF | 4" | 5.12" | 100 | ISO-K | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 2 1/2" | 3.74" | 63 | ISO-K | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 3" | 4.33" | 80 | ISO-K | 1 × 10 -9 torr @ 72° F | 5 psi @ 72° F | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 4" | 5.12" | 100 | ISO-K | 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" | 1.57" | 25 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 000000 |
| 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" | 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 | ||||||||
| 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 | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 0000000 | 000000 |
| 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 | ||||||||
| 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 | ||||||||
| 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 | |
4 3/16" Lg. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1" | 1.57" | 25 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Rigid | 0000000 | 000000 |
| 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. | |||||||||
| 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. | |||||||||
| 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. | |||||||||
| 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 |
Rings for Claw-Clamp and Bolt-Together
High-Vacuum Fittings for Stainless Steel Tubing
- For Use With: Air
- Max. Temperature: 400° F
- Tubing: Use with 304/304L Stainless Steel or 316/316L Stainless Steel
Create airtight seals in high-vacuum systems by placing these rings between two claw-clamp (ISO-K) or bolt-together (ISO-F) fittings. They contain a Viton® fluoroelastomer O-ring—when you clamp or bolt your fittings together, the O-ring compresses to establish the seal.
For technical drawings and 3-D models, click on a part number.
Claw-Clamp Connection | Flanged Connection | Material | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | O-Ring | Inner Ring | Max. Vacuum | Each | |
| 2 1/2" | 3.74" | 63 | ISO-K | 2 1/2" | 5.12" | __ | ISO-F | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
| 3" | 4.33" | 80 | ISO-K | 3" | 5.71" | 80 | ISO-F | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 000000 | 00000 |
| 4" | 5.12" | 100 | ISO-K | 4" | 6.5" | 100 | ISO-F | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 00000 |
| 6" | 7.09" | 160 | ISO-K | 6" | 8.86" | 160 | ISO-F | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 00000 |
Clamps for Claw-Clamp High-Vacuum Fittings for Stainless Steel Tubing
Connect claw-clamp high-vacuum fittings for an airtight seal. For a complete connection, you'll need four clamps and a ring (sold separately).
Double-claw clamps attach to the grooves on the fittings.
Single-claw clamps have a clamp on one end and an exposed bolt on the other. Thread the bolt-end directly into the body of pumps, valves, or other high-vacuum components.
For technical drawings and 3-D models, click on a part number.
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Material | Bolt Material | Max. Vacuum | Each | |
Double Claw | ||||||||
|---|---|---|---|---|---|---|---|---|
| 2 1/2", 3", 4" | 3.74", 4.33", 5.12" | 63, 80, 100 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 00000 |
| 6" | 7.09" | 160 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 0000 |
Single Claw | ||||||||
| 2 1/2", 3", 4" | 3.74", 4.33", 5.12" | 63, 80, 100 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 0000 |
| 6" | 7.09" | 160 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 0000 |
Material | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | O-Ring | Inner Ring | Max. Vacuum | Max. Temp., °F | Each | |
| 2 1/2" | 3.74" | 63 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 0000000 | 000000 |
| 3" | 4.33" | 80 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 000000 | 00000 |
| 4" | 5.12" | 100 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 0000000 | 00000 |
| 6" | 7.09" | 160 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 0000000 | 00000 |
Claw-Clamp High-Vacuum Fittings for Stainless Steel Tubing
An alternative to bolt-together fittings, these handle larger tube OD sizes and have higher vacuum ratings than quick-clamp fittings. Also known as ISO-K high-vacuum fittings, the clamps have claws that grab hold of fittings with flanged ends. To complete a connection, use a ring and four clamps (sold separately). Not for use in pressure applications.
Double-claw clamps attach to the grooves on the fittings.
Single-claw clamps have a clamp on one end and an exposed bolt on the other. Thread the bolt-end directly into the body of pumps, valves, or other high-vacuum components.
For technical drawings and 3-D models, click on a part number.
Adapter, Tube ×
Socket-Connect Tube
| For Tube OD | Flange OD | High-Vacuum Flange Size | Socket Depth | High Vacuum Connection Type | No. of Claw Clamps Required | Material | Max. Vacuum | Each | |
| 2 1/2" | 3.74" | 63 | 7/32" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
| 3" | 4.33" | 80 | 7/32" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 00000 |
| 4" | 5.12" | 100 | 7/32" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 00000 |
| 6" | 7.09" | 160 | 7/32" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
| For Tube OD | Flange OD | High-Vacuum Flange Size | Wall Thick. | High Vacuum Connection Type | No. of Claw Clamps Required | Material | Max. Vacuum | Each | |
| 2 1/2" | 3.74" | 63 | 0.065" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
| 3" | 4.33" | 80 | 0.065" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
| 4" | 5.12" | 100 | 0.083" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
| 6" | 7.09" | 160 | 0.083" | ISO-K | 4 | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 000000 |
Material | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | O-Ring | Inner Ring | Max. Vacuum | Max. Temp., °F | Each | |
| 2 1/2" | 3.74" | 63 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 0000000 | 000000 |
| 3" | 4.33" | 80 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 000000 | 00000 |
| 4" | 5.12" | 100 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 0000000 | 00000 |
| 6" | 7.09" | 160 | ISO-K | Viton® Fluoroelastomer Rubber | 304 Stainless Steel | 1 × 10 -9 torr @ 72° F | 400° | 0000000 | 00000 |
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Material | Bolt Material | Max. Vacuum | Each | |
Double Claw | ||||||||
|---|---|---|---|---|---|---|---|---|
| 2 1/2", 3", 4" | 3.74", 4.33", 5.12" | 63, 80, 100 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 00000 |
| 6" | 7.09" | 160 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 0000 |
Single Claw | ||||||||
| 2 1/2", 3", 4" | 3.74", 4.33", 5.12" | 63, 80, 100 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 0000 |
| 6" | 7.09" | 160 | ISO-K | Aluminum | 18-8 Stainless Steel | 1 × 10 -9 torr @ 72° F | 0000000 | 0000 |