NPS 1/4 Pipe Nipple, ASTM A733

Threaded 18 TPI NPT at each end, the NPS 1/4 pipe nipple (ASTM A733) is cut from 13.716 mm Schedule 40 pipe with a 2.2352 mm wall. Available in 17 lengths from 22.225 to 304.8 mm, each as simplified and threaded STEP.

How these parts are made, and what the levels mean: read the method

• Also searched as: NPS 1/4 pipe nipple, NPS 1/4 x 22.225 to NPS 1/4 x 304.8 pipe nipples
• Model id: astm-a733-nps1-4
• Standard: ASTM A733 · NPS 1/4, pitch 1.411 mm, NPT taper pipe thread (ASME B1.20.1), 60 degree profile, 1:16 taper, right hand

Lengths

Length (mm)	Part key	Simplified	Threaded
22.225	astm-a733-nps1-4x22-225	STEP	STEP
38.1	astm-a733-nps1-4x38-1	STEP	STEP
50.8	astm-a733-nps1-4x50-8	STEP	STEP
63.5	astm-a733-nps1-4x63-5	STEP	STEP
76.2	astm-a733-nps1-4x76-2	STEP	STEP
88.9	astm-a733-nps1-4x88-9	STEP	STEP
101.6	astm-a733-nps1-4x101-6	STEP	STEP
114.3	astm-a733-nps1-4x114-3	STEP	STEP
127	astm-a733-nps1-4x127	STEP	STEP
139.7	astm-a733-nps1-4x139-7	STEP	STEP
152.4	astm-a733-nps1-4x152-4	STEP	STEP
177.8	astm-a733-nps1-4x177-8	STEP	STEP
203.2	astm-a733-nps1-4x203-2	STEP	STEP
228.6	astm-a733-nps1-4x228-6	STEP	STEP
254	astm-a733-nps1-4x254	STEP	STEP
279.4	astm-a733-nps1-4x279-4	STEP	STEP
304.8	astm-a733-nps1-4x304-8	STEP	STEP

Dimensions

Symbol	Name	min	nom	max	Modeled	Rule	Level
l_close_in	Close nipple length, inches		0.875		0.875	nominal	L1
l_close	Close nipple length		22.225		22.225	nominal	L1
D	Outside diameter		13.716		13.716	nominal	L1
T	Wall thickness		2.2352		2.2352	nominal	L1
D_in	Outside diameter, inches		0.54		0.54	nominal	L1
T_in	Wall thickness, inches		0.088		0.088	nominal	L1
n	Threads per inch		18		18	nominal	L1
P	Pitch		0.05555555		0.05555555	nominal	L1
D	Outside diameter of pipe		0.54		0.54	nominal	L1
E0	Pitch diameter at the small end		0.47739		0.47739	nominal	L1
L1	Hand-tight engagement length		0.2278		0.2278	nominal	L1
E1	Pitch diameter at the hand-tight plane		0.49163		0.49163	nominal	L1
L2	Effective thread length		0.4018		0.4018	nominal	L1
E2	Pitch diameter at the end of the effective thread		0.5025		0.5025	nominal	L1
L4	Overall length of external thread		0.5946		0.5946	nominal	L1
h	Height of thread		0.04444		0.04444	nominal	L1
K0	Basic minor diameter at the small end		0.4329		0.4329	nominal	L1
alpha	Flank angle		60		60	nominal	L1
taper	Taper		16		16	nominal	L1

Drawing

As a PDF: CC-ASTMA733-SZ-1-4.pdf.

The NPS 1/4 pipe nipple beside the NPS 1/8 and the NPS 3/8

The NPS 1/4 is number 2 of the 9 ASTM A733 pipe nipples published here, listed from NPS 1/8 to NPS 2.

• Close nipple length, inches (l_close_in): 0.875 mm on the NPS 1/4 pipe nipple, against 0.75 mm on the NPS 1/8 and 1 mm on the NPS 3/8.
• Close nipple length (l_close): 22.225 mm on the NPS 1/4 pipe nipple, against 19.05 mm on the NPS 1/8 and 25.4 mm on the NPS 3/8.
• Outside diameter (D): 13.716 mm on the NPS 1/4 pipe nipple, against 10.287 mm on the NPS 1/8 and 17.145 mm on the NPS 3/8.
• Wall thickness (T): 2.2352 mm on the NPS 1/4 pipe nipple, against 1.7272 mm on the NPS 1/8 and 2.3114 mm on the NPS 3/8.
• Outside diameter, inches (D_in): 0.54 mm on the NPS 1/4 pipe nipple, against 0.405 mm on the NPS 1/8 and 0.675 mm on the NPS 3/8.
• Wall thickness, inches (T_in): 0.088 mm on the NPS 1/4 pipe nipple, against 0.068 mm on the NPS 1/8 and 0.091 mm on the NPS 3/8.
• Threads per inch (n): 18 mm on the NPS 1/4 pipe nipple, against 27 mm on the NPS 1/8 and 18 mm on the NPS 3/8.
• Pitch (P): 0.05555555 mm on the NPS 1/4 pipe nipple, against 0.03703704 mm on the NPS 1/8 and 0.05555555 mm on the NPS 3/8.

Other sizes

• One size smaller: NPS 1/8 Pipe Nipple, ASTM A733, 27 threads per inch, pipe OD 10.287 mm.
• One size larger: NPS 3/8 Pipe Nipple, ASTM A733, 18 threads per inch, pipe OD 17.145 mm.

Documents

• CC-ASTMA733-DS-NPS1-4.pdf: 1/4 datasheet: values with levels, lengths, sources
• CC-ASTMA733-SZ-1-4.pdf: 1/4 drawing: this size's values on the views
• parts.json: the part record of every length (the platform contract)

Sources

anvil-a733-nipples, engineersedge-npt, engineersedge-npt-basic, etb-b36-10, etb-npt, smithcooper-a733-nipples, steeltube-b36-10, ultimatewasher-npt, wikipedia-npt. Full citations: the method page and this size's datasheet.

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