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.
More
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.
Brass nuts have good corrosion resistance and are softer than 316 stainless steel nuts, so they're easier to thread together. Chrome-plated brass nuts have comparable corrosion and wear resistance to aluminum-plated brass nuts, and have a bright, shiny appearance.
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.
- Maximum Pressure: See table
- Maximum Temperature: 120° F, except DIN 477 No. 9: 250° F
Number | Thread Size | Thread Type | Thread Direction | Max. Pressure | For Use With | Each | |
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 |
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 |
- Maximum Pressure: See table
- Maximum Temperature: 120° F, except DIN 477 No. 12: 250° F
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.
- 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 | |||||||||||
| 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 | 000000 |
- 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 | |||||||||||
| 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 | 000000 |
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.
- 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 350 (3,000 psi @ 72° F) | 1/4 | NPT | 2 1/2" | Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas | __ | 000000000 | 00000 |
| CGA 350 (3,000 psi @ 72° F) | 1/4 | NPT | 3" | Carbon Monoxide, Ethane, Ethylene, Hydrogen, Methane, Methyl Fluoride, Natural Gas | __ | 0000000 | 0000 |
| CGA 680, 695 (3,000 psi @ 72° F); CGA 702, 703 (4,700 psi @ 72° F) | 1/4 | NPT | 3" | Air, Argon, Flammable Gases, Helium, Hydrogen, Krypton, Methane, Natural Gas, Neon, Nitrogen, Xenon | __ | 000000000 | 00000 |
| 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 680, 695 (3,000 psi @ 72° F); CGA 702, 703 (4,700 psi @ 72° F) | 1/4 | NPT | 3 1/64" | Air, Argon, Flammable Gases, Helium, Hydrogen, Krypton, Methane, Natural Gas, Neon, Nitrogen, Xenon | __ | 0000000 | 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 680, 695 (3,000 psi @ 72° F); CGA 702, 703 (4,700 psi @ 72° F) | 1/4 | __ | 3 1/64" | Air, Argon, Flammable Gases, Helium, Hydrogen, Krypton, Methane, Natural Gas, Neon, Nitrogen, Xenon | __ | 0000000 | 00000 |
- Maximum Pressure: See table
- Maximum Temperature: 120° F
| Number | Gender | Thread Size | Thread Type | Thread Direction | Max. Pressure | For Use With | Each | |
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 680 | Male | 1.040"-14 | NGO | Right Hand | 4,700 psi @ 72° F | Argon, Helium, Krypton, Neon, Nitrogen, Xenon | 000000000 | 00000 |
| CGA 702 | Male | 1.120"-14 | NGO | Right Hand | 6,400 psi @ 72° F | Air | 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 |