Couplings for Methane | McMaster-Carr

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.

Brass nuts have good corrosion resistance and are softer than 316 stainless steel nuts, so they're easier to thread together. Aluminum-plated brass nuts have better corrosion and wear resistance than unplated brass. Chrome-plated brass nuts have comparable corrosion and wear resistance to aluminum-plated brass nuts, and have a bright, shiny appearance.

Nuts with a plastic grip can be tightened by hand instead of with a wrench.

Nuts with left-hand threads are identified with a notch.

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

Brass
Number	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
CGA 350	0.830"-14	NGO	Left Hand	3,000 psi @ 72° F	Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas	000000000	00000
Aluminum-Plated Brass
CGA 170	9/16"-18	UN/UNF (CGA)	Right Hand	3,000 psi @ 72° F	Air, Argon, Butane, Carbon Dioxide, Helium, Krypton, Methane, Natural Gas, Neon, Nitrogen, Oxygen, Propane, Propylene	000000000	0000
CGA 180	5/8"-18	UN/UNF (CGA)	Right Hand	3,000 psi @ 72° F	Air, Argon, Butane, Carbon Dioxide, Helium, Krypton, Methane, Natural Gas, Neon, Nitrogen, Oxygen, Propane, Propylene	000000000	00000
Chrome-Plated Brass
CGA 350	0.830"-14	NGO	Left Hand	3,000 psi @ 72° F	Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas	000000000	00000

Male

Maximum Pressure: See table
Maximum Temperature: 120° F, except DIN 477 No. 12: 250° F

Brass
Number	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
CGA 510	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	000000000	00000
Brass with Plastic Grip
CGA 510	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	000000000	00000
Chrome-Plated Brass
CGA 510	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	000000000	00000

High-Pressure Threaded Fittings for Compressed Gas

Designed to handle high-pressure welding applications, these fittings are commonly used to connect pressure regulators to compressed gas tanks or cylinders. Fittings are also known as CGA (Compressed Gas Association) fittings. They are brass for good corrosion resistance.

Fittings with left-hand threads are identified with a notch in the nut.

Note: Fittings have a CGA number that corresponds to a specific type of gas. Choose a fitting with the same CGA number as your tank and other system components.

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

Female Tank × Female Regulator

Maximum Pressure: See table
Maximum Temperature: 120° F

CGA Number		Tank Connection			Regulator Connection
Tank	Regulator	Thread Size	Thread Type	Thread Direction	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
Brass
200	510	0.628"-14	NGO	Right Hand	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	000000
300	510	0.830"-14	NGO	Right Hand	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethyl Chloride, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	0000
350	580	0.830"-14	NGO	Left Hand	0.960"-14	NGO	Right Hand	3,000 psi @ 72° F	Argon, Carbon Monoxide, Ethane, Ethylene, Helium, Hydrogen, Krypton, Methane, Methyl Fluoride, Natural Gas, Neon, Nitrogen, Xenon	0000000	00000
410	510	0.855"-14	NGO	Left Hand	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	00000
520	510	0.899"-14	NGO	Right Hand	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	00000
555	510	0.908"-14	NGO	Left Hand	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, LP Gas, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	00000

Male Tank × Male Regulator

Maximum Pressure: See table
Maximum Temperature: 120° F

CGA Number		Tank Connection			Regulator Connection
Tank	Regulator	Thread Size	Thread Type	Thread Direction	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
Brass
510	200	0.880"-14	NGO	Left Hand	0.628"-14	NGO	Right Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	000000
510	300	0.880"-14	NGO	Left Hand	0.830"-14	NGO	Right Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethyl Chloride, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	0000
510	410	0.880"-14	NGO	Left Hand	0.855"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	00000
510	520	0.880"-14	NGO	Left Hand	0.899"-14	NGO	Right Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	0000000	00000
580	350	0.960"-14	NGO	Right Hand	0.830"-14	NGO	Left Hand	3,000 psi @ 72° F	Argon, Carbon Monoxide, Ethane, Ethylene, Helium, Hydrogen, Krypton, Methane, Methyl Fluoride, Natural Gas, Neon, Nitrogen, Xenon	0000000	00000

High-Pressure Nipples for Compressed Gas

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.

Brass nipples have good corrosion resistance and are softer than 316 stainless steel nipples, so they're easier to thread together. Chrome-plated brass nipples have better corrosion and wear resistance than unplated brass nipples and have a bright, shiny appearance.

Nipples with filter help keep the line clean by preventing small particles and other impurities from entering your pressure regulator.

Nipples that tighten by hand should be paired with a nut with a plastic grip.

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	Features		Each
Brass—Tighten With Wrench
CGA 170 (3,000 psi @ 72° F)	1/8	NPT	1 1/4"	Air, Argon, Butane, Carbon Dioxide, Helium, Krypton, Methane, Natural Gas, Neon, Nitrogen, Oxygen, Propane, Propylene	__	000000000	000000
CGA 180 (3,000 psi @ 72° F)	1/8	NPT	2"	Air, Argon, Butane, Carbon Dioxide, Helium, Krypton, Methane, Natural Gas, Neon, Nitrogen, Oxygen, Propane, Propylene	__	000000000	00000
CGA 350 (3,000 psi @ 72° F)	1/4	NPT	2 1/2"	Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas	__	000000000	0000
CGA 500, 580, 590 (3,000 psi @ 72° F); CGA 510 (500 psi @ 72° F)	1/4	NPT	2 1/2"	Acetylene, Argon, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Helium, Isobutane, Krypton, Medical Gas Mixtures, Methane, Methyl Chloride, Natural Gas, Neon, Nitrogen, Propane, Propylene, Sulfur Hexafluoride, Vinyl Chloride, Vinyl Bromide, Xenon	__	000000000	0000
CGA 500, 580, 590 (3,000 psi @ 72° F); CGA 510 (500 psi @ 72° F)	1/4	NPT	3"	Acetylene, Argon, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Helium, Isobutane, Krypton, Medical Gas Mixtures, Methane, Methyl Chloride, Natural Gas, Neon, Nitrogen, Propane, Propylene, Sulfur Hexafluoride, Vinyl Chloride, Vinyl Bromide, Xenon	__	000000000	0000
CGA 500, 580, 590 (3,000 psi @ 72° F); CGA 510 (500 psi @ 72° F)	1/4	NPT	3 1/2"	Acetylene, Argon, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Helium, Isobutane, Krypton, Medical Gas Mixtures, Methane, Methyl Chloride, Natural Gas, Neon, Nitrogen, Propane, Propylene, Sulfur Hexafluoride, Vinyl Chloride, Vinyl Bromide, Xenon	__	000000000	0000
CGA 680, 695 (3,000 psi @ 72° F); CGA 702, 703 (5,500 psi @ 72° F)	1/4	NPT	3 1/64"	Air, Argon, Flammable Gases, Helium, Hydrogen, Krypton, Methane, Natural Gas, Neon, Nitrogen, Xenon	Filter	000000000	00000
Brass—Tighten By Hand
CGA 510 (500 psi @ 72° F); CGA 580, 590 (3,000 psi @ 72° F)	1/4	NPT	3 33/64"	Acetylene, Argon, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Helium, Isobutane, Krypton, Methane, Methyl Chloride, Natural Gas, Neon, Nitrogen, Propane, Propylene, Sulfur Hexafluoride, Vinyl Chloride, Vinyl Bromide, Xenon	__	000000000	00000
Chrome-Plated Brass—Tighten With Wrench
CGA 350 (3,000 psi @ 72° F)	1/4	NPT	3"	Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas	__	000000000	00000
CGA 510 (500 psi @ 72° F); CGA 580, 590 (3,000 psi @ 72° F)	1/4	NPT	3 1/2"	Acetylene, Argon, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Helium, Isobutane, Krypton, Methane, Methyl Chloride, Natural Gas, Neon, Nitrogen, Propane, Propylene, Sulfur Hexafluoride, Vinyl Chloride, Vinyl Bromide, Xenon	__	000000000	00000

Nuts

Maximum Pressure: See table
Maximum Temperature: 120° F

Brass
Number	Gender	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
CGA 350	Female	0.830"-14	NGO	Left Hand	3,000 psi @ 72° F	Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas	000000000	00000
CGA 500	Male	0.880"-14	NGO	Right Hand	3,000 psi @ 72° F	Medical Gas Mixtures	000000000	0000
CGA 510	Male	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	000000000	0000
CGA 580	Male	0.960"-14	NGO	Right Hand	3,000 psi @ 72° F	Argon, Helium, Krypton, Neon, Nitrogen, Xenon	000000000	0000
CGA 590	Male	0.960"-14	NGO	Left Hand	3,000 psi @ 72° F	Sulfur Hexafluoride	000000000	0000
CGA 702	Male	1.120"-14	NGO	Right Hand	4,700 psi @ 72° F	Air	000000000	00000
Brass with Plastic Grip
CGA 510	Male	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	000000000	00000
CGA 580	Male	0.960"-14	NGO	Right Hand	3,000 psi @ 72° F	Argon, Helium, Krypton, Neon, Nitrogen, Xenon	000000000	00000
Aluminum-Plated Brass
CGA 170	Female	9/16"-18	UN/UNF (CGA)	Right Hand	3,000 psi @ 72° F	Air, Argon, Butane, Carbon Dioxide, Helium, Krypton, Methane, Natural Gas, Neon, Nitrogen, Oxygen, Propane, Propylene	000000000	0000
CGA 180	Female	5/8"-18	UN/UNF (CGA)	Right Hand	3,000 psi @ 72° F	Air, Argon, Butane, Carbon Dioxide, Helium, Krypton, Methane, Natural Gas, Neon, Nitrogen, Oxygen, Propane, Propylene	000000000	00000
Chrome-Plated Brass
CGA 350	Female	0.830"-14	NGO	Left Hand	3,000 psi @ 72° F	Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas	000000000	00000
CGA 510	Male	0.880"-14	NGO	Left Hand	500 psi @ 72° F	Acetylene, Butane, Cyclopropane, Dimethyl Ether, Ethylene Oxide, Isobutane, Methane, Methyl Chloride, Natural Gas, Propane, Propylene, Vinyl Bromide, Vinyl Chloride	000000000	00000
CGA 580	Male	0.960"-14	NGO	Right Hand	3,000 psi @ 72° F	Argon, Helium, Krypton, Neon, Nitrogen, Xenon	000000000	00000
CGA 590	Male	0.960"-14	NGO	Left Hand	3,000 psi @ 72° F	Sulfur Hexafluoride	000000000	00000

Through-Wall Fittings for High-Vacuum Chambers

For Use With: See table
Environment Temperature Range: 32° to 300° F
Process Temperature Range: -325° to 995° F
Tubing: Use with 304/304L or 316/316L stainless steel
Specifications Met: See table

Also known as feedthroughs, these fittings transfer liquids, cryogenic liquids, or gasses into high-vacuum chambers for coating, cooling, and leak-testing applications without losing vacuum pressure. Consisting of high-vacuum fittings, metal tubing, and Yor-lok tube fittings, these complete assemblies come ready to install. The quick-clamp (KF) or flanged (CF) high-vacuum fittings form a tight seal on chamber walls. On each end, the Yor-lok fittings include a nut and two sleeves that grip your system’s stainless steel tubing for a leak- and gas-tight connection. The entire assembly is stainless steel so it resists rusting. Not for use in pressure applications.

Quick-clamp fittings meet ISO (International Standards Organization) 2861, which specifies the dimensions of quick-clamp high-vacuum fittings, clamps, and rings to ensure vacuum tightness. These fittings require a clamp and ring (each sold separately) to complete the connection.

Flanged fittings require a gasket and bolt kit (each sold separately) to complete the connection.

Quick-Clamp (ISO-KF) Chamber Connection with Yor-Lok Fittings

Quick Clamp Shown Installed

Quick Clamp

		For Tube
Flange OD	Trade Number	OD	Wall Thick.	Lg.	Max. Vacuum	Material	Specifications Met		Each
For Use With Acetone, Air, Ammonium Hydroxide, Helium, Methane, Nitrogen, Oil, Water
1.18"	16	1/4"	0.028"-0.095"	8"	1 × 10 ^-8 torr @ 72° F	304 Stainless Steel	ISO 2861	0000000	0000000
1.57"	25	1/4"	0.028"-0.095"	8"	1 × 10 ^-8 torr @ 72° F	304 Stainless Steel	ISO 2861	0000000	000000
2.16"	40	1/4"	0.028"-0.095"	8"	1 × 10 ^-8 torr @ 72° F	304 Stainless Steel	ISO 2861	0000000	000000
2.95"	50	1/4"	0.028"-0.095"	8"	1 × 10 ^-8 torr @ 72° F	304 Stainless Steel	ISO 2861	0000000	000000

Flanged (CF) Chamber Connection with Yor-Lok Fittings

Flanged Shown Installed

Flanged

			Bolt Hole		For Tube
Flange OD	Trade Number	Bolt Circle Dia.	Dia.	No. of	OD	Wall Thick.	Lg.	Max. Vacuum	Material		Each
For Use With Acetone, Air, Ammonium Hydroxide, Helium, Methane, Nitrogen, Oil, Water
1 21/64"	16	1 1/16"	11/64"	6	1/4"	0.028"-0.095"	8"	1 × 10 ^-13 torr @ 72° F	304 Stainless Steel	0000000	0000000
2 3/4"	40	2 5/16"	17/64"	6	1/4"	0.028"-0.095"	8"	1 × 10 ^-13 torr @ 72° F	304 Stainless Steel	0000000	000000

Clamps for Quick-Clamp (ISO-KF) Chamber Connection

Clamp with Wing Nut

With Wing Nut
For Flange OD	Trade Number	Material	Max. Vacuum		Each
1.18"	10	Aluminum	1 × 10 ^-7 torr @ 72° F	00000000	00000
1.18"	10, 16	Aluminum	1 × 10 ^-7 torr @ 72° F	00000000	0000
1.18"	16	Aluminum	1 × 10 ^-7 torr @ 72° F	00000000	0000
1.57"	25	Aluminum	1 × 10 ^-7 torr @ 72° F	0000000	00000
2.16"	40	Aluminum	1 × 10 ^-7 torr @ 72° F	0000000	00000
2.95"	50	Aluminum	1 × 10 ^-7 torr @ 72° F	0000000	00000

Rings for Quick-Clamp (ISO-KF) Chamber Connection

Ring

		Material
For Flange OD	Trade Number	O-Ring	Inner Ring	Max. Vacuum		Each
1.18"	16	Fluoroelastomer Rubber	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	00000000	00000
1.57"	25	Fluoroelastomer Rubber	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	0000
2.16"	40	Fluoroelastomer Rubber	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	00000
2.95"	50	Fluoroelastomer Rubber	304 Stainless Steel	1 × 10 ^-7 torr @ 72° F	0000000	00000

Gaskets for Flanged (CF) Chamber Connection

Gasket

For Flange OD	Gasket Material	Specifications Met		Each
1 21/64"	Copper	ASTM F68	0000000	00000
2 3/4"	Copper	ASTM F68	0000000	0000

Bolt Kits for Flanged (CF) Chamber Connection

Bolt Kit

For Flange OD	For Trade Number	Bolt Dia.	Thread Size	No. of Bolts Included	No. of Nuts Included	No. of Washers Included	Bolt Material		Each
1 21/64"	16	0.167"	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