5/8"-18 Nipples | McMaster-Carr

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	System of Measurement System of Measurement

Inch

	Thread Size Thread Size	Show

5/8"-18

	Thread Size Thread Size	Hide

	Thread Type Thread Type

	Pipe Size Pipe Size

	Type Type


Adapter	Nut

	For Use With For Use With

	Gender Gender

Male

Female

	Shape Shape

	Straight

	Connection Style Connection Style

Threaded

Barbed

Flared

	Connection Type Connection Type


Pipe	Hose

Tube

	Material Material

Brass

	For Tube OD For Tube OD

3/8"

	CGA Number CGA Number

022

032

180

	Thread Direction Thread Direction

Right Hand

	Flared Angle Flared Angle

45°

	For Hose ID For Hose ID

1/4"

3/8"

	For Tube Material For Tube Material

Copper

Brass

	Maximum Pressure Maximum Pressure

	Length Length

	Maximum Temperature Maximum Temperature

Less than 200° F

250° to 499° F

	Minimum Temperature Minimum Temperature

-99° to -50° F

-49° to 0° F

Not Rated

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

RoHS Compliant with
Exemptions

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

REACH Compliant

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22 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.

Metal Barbed Hose Fittings for Air and Water

Slide the barbed end into rubber hose and secure with the appropriate clamp or crimp-on hose ferrule.

Brass fittings are softer than other metal fittings, so they’re easier to thread together. Plain brass fittings have good corrosion resistance. Fittings with a threaded end are also known as hose nipples.

Fittings with a 45° flared end are also known as refrigeration and SAE fittings.

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

Straight Adapters, Hose × UN/UNF (SAE 45°) Male Flared Tube

Maximum Pressure: 250 psi @ 72° F
Temperature Range: -40° to 160° F
Attachment Type: Use Crimp-On Hose Ferrules, except For 1/2" Hose ID: Use Band-and-Buckle Clamps
Specifications Met: SAE J476

Brass
For Hose ID	For Tube OD	Thread Size	Pkg. Qty.		Pkg.
1/4"	3/8"	5/8"-18	5	0000000	000000
3/8"	3/8"	5/8"-18	5	0000000	00000

Metal Push-On Barbed Hose Fittings for Air and Water

Fittings have sharper barbs than standard barbed hose fittings to grip rubber push-on hose with no clamps or ferrules required. The more you pull on the fittings, the tighter the hose will grip.

Brass fittings are softer than other metal fittings, so they’re easier to thread together. They have good corrosion resistance.

Fittings with a flared end meet JIC or SAE standards for dimensions. Fittings with a 45° flared end are also known as refrigeration and SAE fittings.The optional installation tool (sold separately) allows you to connect large quantities of barbed fittings to push-on hose. Use the built-in cutter to squarely cut the hose without fraying. Next, lubricate either the push-on hose, fitting or both. Then, clamp the hose into the tool’s vise and apply light pressure on the handle to drive into the fitting.

Note: To ensure proper connection, the barbed end has to be pushed in all the way, with the hose end concealed by the ring.

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

Straight Adapters, Hose × UN/UNF (Tube End) Male 45° Flared Tube

Maximum Pressure: 300 psi @ 72° F
Temperature Range: -20° to 150° F
Specifications Met: SAE J512

Adapters
			Ring Stop					Replacement Ring Stops
For Hose ID	For Tube OD	Thread Size	Material	Color	Pkg. Qty.		Pkg.	Pkg. Qty.		Pkg.
Brass
3/8"	3/8"	5/8"-18	Plastic	Yellow	1	00000000	00000	25	000000000	00000

Installation Tool

				Mounting Hole
For Hose ID Range	Lg.	Ht.	Dp.	Dia.	No. of	Mounting Fasteners Included		Each
1/4" to 3/4"	13 1/2"	7"	2 3/8"	7/16"	4	No	00000000	0000000

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. Aluminum-plated brass nuts have better corrosion and wear resistance than unplated brass.

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

Female Nut

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

Aluminum-Plated Brass
Number	Thread Size	Thread Type	Thread Direction	Max. Pressure	For Use With		Each
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	000000

Threaded Hose Fittings for Compressed Gas

Use these fittings to connect welding hose to pressure regulators and torches. They are also known as CGA (Compressed Gas Association) fittings. Fittings are brass for good corrosion resistance.

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.

Straight Adapters, Male Hose

Maximum Pressure: 200 psi @ 72° F
Maximum Temperature: 120° F

Brass
CGA Number	Gas Fitting Size	Thread Size	Thread Type	Thread Direction	For Use With		Each
032 x 022	B	5/8"-18 x 9/16"-18	UN/UNF (CGA)	Right Hand	Argon, Helium, Krypton, Neon, Nitrogen, Oxygen, Xenon	0000000	000000

Straight Adapters, Male Hose × Male Pipe

Maximum Pressure: 200 psi @ 72° F
Maximum Temperature: 120° F

Male Hose Connection					Male Pipe Connection
CGA Number	Gas Fitting Size	Thread Size	Thread Type	Thread Direction	Pipe Size	Thread Type	Thread Direction	For Use With		Each
Brass
032	B	5/8"-18	UN/UNF (CGA)	Right Hand	1/4	NPT	Right Hand	Argon, Helium, Krypton, Neon, Nitrogen, Xenon	0000000	000000

45° Flared Fittings for Copper and Brass Tubing

Temperature Range: -65° to 250° F
Tubing: Use with seamless brass and copper that meets ASTM B280

No sleeve is required to assemble these fittings, which makes for a faster, more convenient installation compared to 37° flared fittings. They require a nut (sold separately) for each tube end. Fittings are also known as refrigeration and SAE fittings. They are brass for good corrosion resistance.

NPTF (Dryseal) threads are compatible with NPT threads.

Copper tube size is the accepted designation of the copper tubing industry, not the actual tube OD.

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

Straight Adapters, Tube × Male Threaded Pipe

For Use With:
NPTF Threads: Air, Cutting Oil, Diesel Fuel, Fuel Oil, Mineral Oil, Refrigerant, Water; except adapters for 1/8" and 1" tube OD are not for use with fuel oil
BSPT Threads: Air, Cutting Oil, Diesel Fuel, Mineral Oil, Refrigerant, Water
Specifications Met: See table

For Tube
OD	Wall Thick.	Pipe Size	Material	Max. Pressure	Specifications Met		Each
NPTF Threads
3/8"	0.032"	1/8	Brass	1,000 psi @ 72° F	SAE J512, SAE J513, UL Listed	000000000	00000
3/8"	0.032"	1/4	Brass	1,000 psi @ 72° F	SAE J512, SAE J513, UL Listed	000000000	0000
3/8"	0.032"	3/8	Brass	1,000 psi @ 72° F	SAE J512, SAE J513, UL Listed	000000000	0000
3/8"	0.032"	1/2	Brass	1,000 psi @ 72° F	SAE J512, SAE J513, UL Listed	000000000	0000
3/8"	0.032"	3/4	Brass	1,000 psi @ 72° F	SAE J512, SAE J513, UL Listed	000000000	00000
BSPT Threads
3/8"	0.032"	1/8	Brass	1,000 psi @ 72° F	SAE J512, SAE J513	00000000	0000
3/8"	0.032"	1/4	Brass	1,000 psi @ 72° F	SAE J512, SAE J513	000000000	0000
3/8"	0.032"	3/8	Brass	1,000 psi @ 72° F	SAE J512, SAE J513	000000000	0000
3/8"	0.032"	1/2	Brass	1,000 psi @ 72° F	SAE J512, SAE J513	000000000	0000

Nuts

(A) Short Nut

(B) Short Nut

(A) Long Nut

(B) Long Nut

For Use With: Air, Cutting Oil, Diesel Fuel, Fuel Oil, Mineral Oil, Refrigerant, Water; except nuts for 1" tube OD are not for use with fuel oil
Specifications Met: SAE J512, SAE J513, UL Listed; except nuts for 1" tube OD meet SAE J512 and SAE J513 only

	For Tube
	OD	Wall Thick.	Nut Material	Max. Pressure	Lg.		Each
Short Nuts
A	3/8"	0.032"	Brass	1,000 psi @ 72° F	29/32"	000000000	00000
A	3/8"	0.065"	Brass	1,000 psi @ 72° F	1"	000000000	0000
B	3/8"	0.032"	Brass	1,000 psi @ 72° F	27/32"	000000000	00000
Long Nuts
A	3/8"	0.065"	Brass	1,000 psi @ 72° F	1 5/16"	000000000	0000
B	3/8"	0.032"	Brass	1,000 psi @ 72° F	1 1/16"	000000000	00000