Couplings for Ammonia | McMaster-Carr

Commonly used in high-pressure welding applications, these nipples connect your tank to the inlet of a pressure regulator. One side has a threaded pipe end and the other side has a rounded end that sits inside a threaded nut (sold separately) so you can make a threaded connection.

316 stainless steel nipples have excellent corrosion resistance.

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

Nipples, Tank × Male Regulator

Maximum Pressure: See table
Maximum Temperature: 120° F

	Regulator Connection
For Number (Max. Pressure)	Pipe Size	Thread Type	Lg.	For Use With		Each
316 Stainless Steel—Tighten With Wrench
CGA 705 (3,000 psi @ 72° F)	1/4	NPT	2 1/2"	Ammonia	000000000	000000

Nuts

Maximum Pressure: See table
Maximum Temperature: 120° F

316 Stainless Steel
Number	Gender	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
CGA 705	Female	1.125"-14	UNS	Right Hand	3,000 psi @ 72° F	Ammonia	000000000	000000

Nuts for High-Pressure Nipples for Compressed Gas

Slide a high-pressure hose nipple for compressed gas into one of these nuts to connect a pipe to the inlet of a pressure regulator. They are also known as CGA (Compressed Gas Association) nuts and inlet nuts.

316 stainless steel nuts have excellent corrosion resistance.

Note: Nuts have a CGA, BS, or DIN number that corresponds to a specific type of gas. Choose a nut with the same number as your tank and other system components.

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

Female

Maximum Pressure: See table
Maximum Temperature: 120° F, except DIN 477 No. 9: 250° F

316 Stainless Steel
Number	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
CGA 705	1.125"-14	UNS	Right Hand	3,000 psi @ 72° F	Ammonia	000000000	000000

Compression Fittings for Plastic Tubing—Chemicals

For Use With: PFA Plastic: Hydrochloric Acid, Sulfuric Acid
PTFE Plastic: Alcohol, Ammonia, Benzoic Acid, Bleach, Bromine, Coolant, Fluoboric Acid, Hydrochloric Acid, Hydrofluoric Acid, Nitric Acid, Organic Solvents, Sodium Carbonate, Sulfuric Acid
Temperature Range: PFA Plastic: 0° to 350° F
PTFE Plastic: -40° to 185° F
Tubing: PFA Plastic: Use with hard (Durometer 50D-65D) PFA or PTFE plastic
PTFE Plastic: Use with hard (Durometer 60D) PFA or PTFE plastic

A single sleeve (ferrule) compresses the tubing as you tighten the nut, creating a strong seal. The nut and sleeve are included. Fittings are also known as flareless fittings.

PTFE fittings are highly resistant to most acids, alcohols, detergents, and solvents. They’re made by machining. Their nut is made of PVDF, which is resistant to halogens such as chlorine and bromine, strong acids such as hydrofluoric and nitric acids, and organic solvents.

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

Straight Adapters, Tube × Male Threaded Pipe

NPT Threads
For Tube OD	Pipe Size	Material	Color	Max. Pressure		Each
4mm	1/8	PTFE Plastic	White	100 psi @ 72° F	000000000	000000
6mm	1/8	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
6mm	1/4	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
8mm	1/4	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	1/4	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	3/8	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
12mm	3/8	PTFE Plastic	White	80 psi @ 72° F	000000000	00000
12mm	1/2	PTFE Plastic	White	80 psi @ 72° F	000000000	00000

Straight Adapters, Tube × Female Threaded Pipe

NPT Threads
For Tube OD	Pipe Size	Material	Color	Max. Pressure		Each
4mm	1/8	PTFE Plastic	White	100 psi @ 72° F	000000000	000000
6mm	1/8	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
6mm	1/4	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
8mm	1/4	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	1/4	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	3/8	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
12mm	1/2	PTFE Plastic	White	80 psi @ 72° F	000000000	00000

Through-Wall Straight Adapters, Tube × Male Threaded Pipe

Through-wall fittings are also known as bulkhead couplings and panel-mount couplings; they mount through your wall or panel to create an inlet or outlet.

NPT Threads
For Tube OD	Pipe Size	Material	Color	Max. Pressure	For Hole Dia.	For Max. Wall Thick.		Each
4mm	1/8	PTFE Plastic	White	100 psi @ 72° F	25/64"	1/4"	000000000	000000
6mm	1/8	PTFE Plastic	White	100 psi @ 72° F	29/64"	1/4"	000000000	00000
6mm	1/4	PTFE Plastic	White	100 psi @ 72° F	29/64"	1/4"	000000000	00000
8mm	1/4	PTFE Plastic	White	100 psi @ 72° F	37/64"	1/4"	000000000	00000
10mm	1/4	PTFE Plastic	White	100 psi @ 72° F	45/64"	1/4"	000000000	00000
10mm	3/8	PTFE Plastic	White	100 psi @ 72° F	45/64"	1/4"	000000000	00000

Through-Wall Straight Adapters, Tube × Female Threaded Pipe

Through-wall fittings are also known as bulkhead couplings and panel-mount couplings; they mount through your wall or panel to create an inlet or outlet.

NPT Threads
For Tube OD, mm	Pipe Size	Material	Color	Max. Pressure	For Hole Dia.	For Max. Wall Thick.		Each
4	1/8	PTFE Plastic	White	100 psi @ 72° F	25/64"	1/4"	000000000	000000
6	1/8	PTFE Plastic	White	100 psi @ 72° F	29/64"	1/4"	000000000	00000
6	1/4	PTFE Plastic	White	100 psi @ 72° F	29/64"	1/4"	000000000	00000
8	1/4	PTFE Plastic	White	100 psi @ 72° F	37/64"	1/4"	000000000	00000
10	1/4	PTFE Plastic	White	100 psi @ 72° F	45/64"	1/4"	000000000	00000
10	3/8	PTFE Plastic	White	100 psi @ 72° F	45/64"	1/4"	000000000	00000

Straight Connectors, Tube

For Tube OD	Material	Color	Max. Pressure		Each
4mm	PTFE Plastic	White	100 psi @ 72° F	000000000	000000
6mm	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
8mm	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
12mm	PTFE Plastic	White	80 psi @ 72° F	000000000	00000

Through-Wall Straight Connectors, Tube

Through-wall fittings are also known as bulkhead couplings and panel-mount couplings; they mount through your wall or panel to create an inlet or outlet.

For Tube OD	Material	Color	Max. Pressure	For Hole Dia.	For Max. Wall Thick.		Each
4mm	PTFE Plastic	White	100 psi @ 72° F	25/64"	1/4"	000000000	000000
6mm	PTFE Plastic	White	100 psi @ 72° F	29/64"	1/4"	000000000	00000
8mm	PTFE Plastic	White	100 psi @ 72° F	37/64"	1/4"	000000000	00000
10mm	PTFE Plastic	White	100 psi @ 72° F	45/64"	1/4"	000000000	00000
12mm	PTFE Plastic	White	80 psi @ 72° F	57/64"	1/4"	000000000	00000

Straight Reducers, Tube

For Tube OD (A)	For Tube OD (B)	Material	Color	Max. Pressure		Each
6mm	4mm	PTFE Plastic	White	100 psi @ 72° F	000000000	000000
8mm	6mm	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	6mm	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
10mm	8mm	PTFE Plastic	White	100 psi @ 72° F	000000000	00000
12mm	8mm	PTFE Plastic	White	80 psi @ 72° F	000000000	00000
12mm	10mm	PTFE Plastic	White	80 psi @ 72° F	000000000	00000
16mm	12mm	PTFE Plastic	White	80 psi @ 72° F	000000000	00000
19mm	15mm	PTFE Plastic	White	80 psi @ 72° F	000000000	000000
20mm	12mm	PTFE Plastic	White	65 psi @ 72° F	000000000	000000
26mm	12mm	PTFE Plastic	White	65 psi @ 72° F	000000000	000000

Quick-Disconnect Couplings for Plastic
and Rubber Tubing—Chemicals

For Use With: Ammonia, Ethanol, Phosphoric Acid (70%), Sodium Carbonate
Temperature Range: 32° to 160° F

Couplings consist of a plug and a socket (sold separately) that join with a latch, so you can frequently connect and disconnect your line. To connect, insert the plug into the socket; to disconnect, press the latch on the socket and remove the plug. Plugs and sockets are polypropylene, which has excellent chemical, impact, and abrasion resistance.

Plugs and sockets with shut-off have a valve to stop the flow when the coupling is separated so fluid won’t spill from your line.

Note: For a complete coupling, order a plug and a socket with the same coupling size.

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

Straight Plugs, Barbed Tube

Barbed plugs insert into tubing and secure with a clamp.

Open Flow
Coupling Size	Plug OD	For Tube ID	Material	Color	Max. Pressure		Each
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	0000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	0000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	0000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	0000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	0000
With Shut-Off
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000

Straight Plugs, Male Threaded Pipe

Open Flow
Coupling Size	Plug OD	Pipe Size	Material	Color	Max. Pressure		Each
NPT Threads
1/8	5/16"	1/8	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	0000
3/8	3/4"	3/8	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	0000
3/8	3/4"	1/2	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	0000
With Shut-Off
NPT Threads
1/8	5/16"	1/8	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000

90° Elbow Plugs, Barbed Tube

Barbed plugs insert into tubing and secure with a clamp.

Open Flow
Coupling Size	Plug OD	For Tube ID	Material	Color	Max. Pressure		Each
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
With Shut-Off
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000

Straight Sockets, Barbed Tube

Barbed sockets insert into tubing and secure with a clamp.

Open Flow
Coupling Size	For Plug OD	For Tube ID	Material	Color	Max. Pressure		Each
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	000000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
With Shut-Off
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000

Through-Wall Straight Sockets, Barbed Tube

Barbed sockets insert into tubing and secure with a clamp.

Through-wall sockets are also known as bulkhead sockets and panel-mount sockets; they mount through your wall or panel to create an inlet or outlet.

Open Flow
Coupling Size	For Plug OD	For Tube ID	Material	Color	Max. Pressure	For Hole Dia.	For Max. Wall Thick.		Each
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	1/2"	1/2"	00000000	000000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	1/2"	1/2"	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	11/16"	1/2"	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	11/16"	1/2"	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	1 13/16"	1/4"	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	1 13/16"	1/4"	00000000	00000
With Shut-Off
1/8	5/16"	1/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	1/2"	1/2"	00000000	00000
1/8	5/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	1/2"	1/2"	00000000	00000
1/4	7/16"	1/4"	Polypropylene Plastic	Beige	120 psi @ 72° F	11/16"	1/2"	00000000	00000
1/4	7/16"	3/8"	Polypropylene Plastic	Beige	120 psi @ 72° F	11/16"	1/2"	00000000	00000
3/8	3/4"	3/8"	Polypropylene Plastic	Gray	60 psi @ 72° F	1 13/16"	1/4"	00000000	00000
3/8	3/4"	1/2"	Polypropylene Plastic	Gray	60 psi @ 72° F	1 13/16"	1/4"	00000000	00000

Straight Sockets, Male Threaded Pipe

Open Flow
Coupling Size	For Plug OD	Pipe Size	Material	Color	Max. Pressure		Each
NPT Threads
1/8	5/16"	1/8	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	000000
1/4	7/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
BSPT Threads
1/8	5/16"	1/8	Polypropylene Plastic	Beige	120 psi @ 72° F	000000000	00000
1/8	5/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	000000000	00000
With Shut-Off
NPT Threads
1/8	5/16"	1/8	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/8	5/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
1/4	7/16"	3/8	Polypropylene Plastic	Beige	120 psi @ 72° F	00000000	00000
3/8	3/4"	3/8	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
3/8	3/4"	1/2	Polypropylene Plastic	Gray	60 psi @ 72° F	00000000	00000
BSPT Threads
1/8	5/16"	1/8	Polypropylene Plastic	Beige	120 psi @ 72° F	000000000	00000
1/8	5/16"	1/4	Polypropylene Plastic	Beige	120 psi @ 72° F	000000000	00000

How to Identify and Measure Fittings

High-Pressure Nipples for Compressed Gas

Nuts for High-Pressure Nipples for Compressed Gas

Compression Fittings for Plastic Tubing—Chemicals

Quick-Disconnect Couplings for Plasticand Rubber Tubing—Chemicals

Quick-Disconnect Couplings for Plastic
and Rubber Tubing—Chemicals