2.95" OD Flanges | McMaster-Carr

Clear All

	Type Type


Adapter	Cap

Connector	Reducer

	Connection Style Connection Style

	System of Measurement System of Measurement

Inch

	For Tube OD For Tube OD

3/4"

1 1/2"

2 1/2"

	Shape Shape


Straight	Cap/Plug

90° Elbow	Tee

45° Elbow	Cross

	High-Vacuum Flange Size High-Vacuum Flange Size

100

	Material Material

Aluminum

Stainless Steel

	Flange OD Flange OD	Show

2.95"

	Flange OD Flange OD	Hide

	For Tube Material For Tube Material

Stainless Steel

Glass

	High Vacuum Connection Type High Vacuum Connection Type

ISO-KF

ISO-K

	Connection Type Connection Type


Pipe	Tube

Hose

	Length Length

	Quick-Clamp Connection Type Quick-Clamp Connection Type

Standard

	Maximum Temperature Maximum Temperature

250° to 499° F

	Minimum Temperature Minimum Temperature

-99° to 0° F

	Maximum Vacuum Maximum Vacuum

1 × 10^-9 torr @
72° F

1 × 10^-8 torr @
72° F

1 × 10^-7 torr @
72° F

	Sterilize With Sterilize With

Steam (Autoclaving)

Not Recommended

	REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)

REACH Compliant

	RoHS (Restriction of Hazardous Substances) RoHS (Restriction of Hazardous Substances)

RoHS Compliant

	DFARS (Defense Acquisition Regulations Supplement) DFARS (Defense Acquisition Regulations Supplement)

DFARS Specialty Metals
COTS-Exempt

	Specifications Met Specifications Met

ISO

	Vacuum Rating Vacuum Rating

High

	Pipe Size Pipe Size

76 Products

How to Identify and Measure Fittings

Pipe size is an industry designation, not the actual size. View information about how to measure threaded and unthreaded pipe and pipe fittings.

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).

Aluminum fittings have good corrosion resistance and are lighter than stainless steel fittings. 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.

Straight Adapters, Tube × Male Threaded Pipe

Fittings with threaded pipe end require PTFE tape for sealing the threads.

NPT Threads
For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Pipe Size	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	1/4	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	0000000
2"	2.95"	50	ISO-KF	1/2	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000
2"	2.95"	50	ISO-KF	1	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000
2"	2.95"	50	ISO-KF	2	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000

Straight Adapters, Tube × Female Threaded Pipe

Fittings with threaded pipe end require PTFE tape for sealing the threads.

NPT Threads
For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Pipe Size	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	1/4	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	000000

Straight Adapters, Tube × Barbed Hose

Fittings with barbed hose end connect flexible hose or tubing to your system. Secure with a hose clamp (sold separately).

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	For Hose ID	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	1 5/8"	Aluminum	1 × 10 ^-7 torr @ 72° F	0000000	000000
2"	2.95"	50	ISO-KF	2"	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	00000

Straight Adapters, Tube × Butt-Weld Tube

Fittings with butt-weld end weld to tubing for a permanent connection. Fittings with butt-weld end are also known as ferrules.

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Wall Thick.	Material	Max. Vacuum	Lg.		Each
2"	2.95"	50	ISO-KF	0.065"	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	3/4"	0000000	000000
2"	2.95"	50	ISO-KF	0.065"	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	1 9/16"	0000000	00000

Straight Adapters, Tube × Socket-Connect Tube

Fittings with socket-connect end weld to tubing for a permanent connection.

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000

Straight Adapters, Tube × Flanged Tube

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
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	0000000

Copper Gasket for 4" Tube OD (Flanged End)

0000000

Each

000000

Straight Adapters, Tube × Claw-Clamp Tube

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
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	0000000
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

Ring for 4" Tube OD (Claw-Clamp End)	0000000	Each	000000
Double-Claw Clamp	0000000	Each	0000
Ring for 3" Tube OD (Claw-Clamp End)	000000	Each	00000
Ring for 2 1/2" Tube OD (Claw-Clamp End)	0000000	Each	00000

Straight Connectors, Tube

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Lg.	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	5 1/2"	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	0000000
2"	2.95"	50	ISO-KF	12 1/2"	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000

Straight Reducers, Tube

Tube Connection (A)				Tube Connection (B)
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	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	3/4"	1.18"	16	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000
2"	2.95"	50	ISO-KF	1"	1.57"	25	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	00000
2"	2.95"	50	ISO-KF	1 1/2"	2.16"	40	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	00000

90° Elbow Connectors, Tube

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	0000000

45° Elbow Connectors, Tube

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	0000000

Tee Connectors, Tube

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	0000000

Inline Tee Reducers, Tube

Inline tees are also known as branch tees.

Tube Connection (A)				Tube Connection (B)
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	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	1"	1.57"	25	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	0000000
2"	2.95"	50	ISO-KF	1 1/2"	2.16"	40	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	000000

Cross Connectors, Tube

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	0000000

Caps

For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum		Each
2"	2.95"	50	ISO-KF	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	000000

Clamps

Clamp with Wing Nut

Spring-Loaded Clamp

Clamps tighten by hand. Spring-loaded clamps are also known as toggle clamps.

with Wing Nut
For Tube OD	For Flange OD	For High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum	Lanyard Length		Each
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

Rings

Ring

Ring with Stainless Steel Screen

Ring with Aluminum Outer Ring

Use these rings with quick-clamp high-vacuum fittings. They consist of a stainless steel inner ring covered by a fluoroelastomer O-ring.

Rings
For Tube OD	For Flange OD	For High-Vacuum Flange Size	High Vacuum Connection Type	Inner Ring Material	Max. Vacuum	Max. Pressure		Each
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	0000
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
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

Rigid Hose

Flexible Hose

Hose absorbs moderate vibration

3 3/16" Lg.
For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Material	Max. Vacuum	Bend Radius	Flexibility		Each
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

Valves with Shut-Off

Valves are also known as vacuum isolation valves. They connect to a vacuum system so you can install gauges, release gases, and remove air. They operate manually and have a compact body that fits easily into tight spaces.

Actuation	For Tube OD	Flange OD	High-Vacuum Flange Size	Max. Vacuum	Body Material	Overall Ht.	Overall Lg.		Each
Manual	3/4"	1 3/16"	16	10 ^-7 torr @ 72° F	304 Stainless Steel	4 1/8"	2 1/4"	00000000	0000000
Manual	1"	1 9/16"	25	10 ^-7 torr @ 72° F	304 Stainless Steel	5 5/8"	3"	00000000	000000
Manual	1 1/2"	2 1/8"	40	10 ^-7 torr @ 72° F	304 Stainless Steel	6 3/8"	3 7/8"	00000000	000000
Manual	2"	2 15/16"	50	10 ^-7 torr @ 72° F	304 Stainless Steel	8"	4 1/2"	00000000	00000000

Quick-Connect High-Vacuum Fittings for Stainless Steel Tubing

Twist these fittings onto high-vacuum tubing to quickly make sealed, high-vacuum connections without the need for clamping, welding, or tools. To connect, insert your tubing into the fitting and twist the collar on the end of the fitting; an O-ring on the inside of the fitting compresses to form the seal. Also known as quick-disconnects, they're as easy to twist off as they are to twist on. Not for use in pressure applications.

Adapters have a quick-connect fitting on one side and a quick-clamp fitting on the other. Use them to attach and remove components for one-off uses or to adapt your quick-clamp system to connect to glass tubing. Quick-clamp fittings are also known as KF, QF, and NW fittings; they require a clamp and ring (sold separately) to complete the connection.

For technical drawings and 3-D models, click on a part number.

Straight Adapters, Quick Connect × Quick Clamp

Straight Adapter, Quick Connect × Quick Clamp

Adapters
	Quick Clamp Tube Connection											Replacement O-Rings
For Tube OD (Quick Connect)	For Tube OD	Flange OD	High-Vacuum Flange Size	High Vacuum Connection Type	Wall Thick.	Max. Vacuum	Material	O-Ring Material	Temp. Range, °F		Each		Each
2"	2"	2.95"	50	ISO-KF	0.118"	1 × 10 ^-8 torr @ 72° F	304 Stainless Steel	Buna-N Rubber	-40° to 250°	0000000	0000000	0000000	00000