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NPT pipe plugs: square head, hex head, round head and hex socket (ASME B16.11; Dryseal NPTF, flush PTF) 1/16 to 6 in — head size, length, socket + envelope models

Name: NPT pipe plugs: square head, hex head, round head and hex socket (ASME B16.11; Dryseal NPTF, flush PTF) 1/16 to 6 in — head size, length, socket + envelope models dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

What are the head and socket sizes of a 1/4 or 1/2 NPT pipe plug? · Standard part · basis: Penn Machine's forged square head plug catalog (inches), wermac.org's ASME B16.11 plug tables (mm), and Alma Bolt's and American Fastener's hex socket plug sheets (inches); 18 hex-socket plug envelopes as files

Also called: npt plug dimensions, 1/4 npt hex socket plug allen key size, 1/8 npt plug hex size, 1/2 npt square head plug dimensions, 3/8 npt socket plug key size, npt pipe plug head size, 1/4 npt plug length, asme b16.11 square head plug, 3/4 npt plug allen key size, npt plug stl step, 1/8 npt plug tap drill, hex socket pipe plug torque

Exact dimensions. Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part. Mating features

length: 7.9 mm
width: 7.9 mm
height: 8.2 mm

Notes

Square head plugs (forged steel, ASME B16.11 family), Penn Machine, inches, 1/8 to 6: A, B, C and the thread length L, with weights. The text read does not define the letters. They were matched to wermac.org's mm table: Penn A tracks wermac's B (width across flats: 1/2 → 0.563 in = 14.3 mm against 14; 1 → 0.813 in = 20.6 mm against 21; 2 → 1.313 in = 33.3 mm against 32), Penn B tracks wermac's E (length: 3/4 → 0.625 in = 15.9 against 16; 2 → 0.880 in = 22.4 against 22) and Penn C tracks wermac's C (square height: 1/2 → 0.380 in = 9.7 mm against 10). That matching is the Xem reading, not a statement of either source. At 4 in Penn's A is 2.500 in (63.5 mm) against wermac's 65 mm. The mm tables are minimum values (wermac: 'min'), so small differences are expected.
wermac.org tables are third-party transcriptions of ASME B16.11 plugs, mm, NPS 1/2 to 4, with the page's own letters; there is no hex-socket table on that page (hex-socket plugs are not an ASME B16.11 product in the sources read). In the round head table the 2-1/2 length E is 37 where hex and square give 27; probably a typo, shown as printed. A hex-head table from a cast stainless catalog (150# CSS) was read but its columns could not be assigned, so it is not used.
Hex socket plugs: Alma Bolt prints two series with the same columns, Dryseal NPTF (1/16 to 2) and flush PTF (1/16 to 1-1/4): OD D, threads per inch, hex socket J (across flats), key engagement T (min), wall G (min), overall length L (max / min), tightening torque, tap drill. American Fastener's flush-seal sheet has the same numbers as Alma's PTF rows. Alma does not define L or G; American Fastener's headers are compressed, so L as overall length and G as wall thickness follow the order of its columns. Alma heads the NPTF table 'tapered 3/4 in diameter per foot' and the flush PTF table 'tapered 7/8 in diameter per foot'. See npt-thread-dimensions-asme-b1-20-1 for the thread numbers.
Files: straight cylinders at the OD D with the L max overall length and a flat-bottomed hex socket of J across flats and T min depth, 10 Dryseal NPTF sizes and 8 flush PTF sizes. The real thread is tapered; here the printed OD D is carried as a plain cylinder at that diameter (taper not drawn). Square-head and hex-head plugs have no file: their head edges, chamfers and thread dimensions are not given as numbers that define the shape. Countersunk hex head plugs are not tabulated (no source read).
McMaster-Carr sells pipe plugs (square, hex head, socket, SAE J531 etc.) with per-part STEP; its SAE J531 and steel socket plug categories are linked, not copied.

NPT pipe plugs: square head, hex head, round head and hex socket… size chart

table (source)	NPS	TPI	across flats / OD	head height	length / thread length	key engagement T	wall G	torque	tap drill	note
square head plug, Penn Machine (in)	1/8	—	A 0.281	C 0.250	B 0.380; thread L 0.273	—	—	—	—	letters as printed; weight (carbon steel) 0.02 lb
square head plug, Penn Machine (in)	1/4	—	A 0.380	C 0.250	B 0.440; thread L 0.395	—	—	—	—	letters as printed; weight (carbon steel) 0.03 lb
square head plug, Penn Machine (in)	3/8	—	A 0.440	C 0.313	B 0.500; thread L 0.407	—	—	—	—	letters as printed; weight (carbon steel) 0.06 lb
square head plug, Penn Machine (in)	1/2	—	A 0.563	C 0.380	B 0.563; thread L 0.534	—	—	—	—	letters as printed; weight (carbon steel) 0.11 lb
square head plug, Penn Machine (in)	3/4	—	A 0.625	C 0.440	B 0.625; thread L 0.553	—	—	—	—	letters as printed; weight (carbon steel) 0.18 lb
square head plug, Penn Machine (in)	1	—	A 0.813	C 0.500	B 0.750; thread L 0.661	—	—	—	—	letters as printed; weight (carbon steel) 0.35 lb
square head plug, Penn Machine (in)	1-1/4	—	A 0.940	C 0.563	B 0.813; thread L 0.681	—	—	—	—	letters as printed; weight (carbon steel) 0.6 lb
square head plug, Penn Machine (in)	1-1/2	—	A 1.125	C 0.625	B 0.813; thread L 0.681	—	—	—	—	letters as printed; weight (carbon steel) 0.82 lb
square head plug, Penn Machine (in)	2	—	A 1.313	C 0.690	B 0.880; thread L 0.697	—	—	—	—	letters as printed; weight (carbon steel) 1.36 lb
square head plug, Penn Machine (in)	2-1/2	—	A 1.500	C 0.750	B 1.063; thread L 0.933	—	—	—	—	letters as printed; weight (carbon steel) 2.21 lb
square head plug, Penn Machine (in)	3	—	A 1.690	C 0.813	B 1.125; thread L 1.016	—	—	—	—	letters as printed; weight (carbon steel) 3.47 lb
square head plug, Penn Machine (in)	3-1/2	—	A 1.875	C 0.875	B 1.187; thread L 1.071	—	—	—	—	letters as printed; weight (carbon steel) 4.73 lb
square head plug, Penn Machine (in)	4	—	A 2.500	C 1.000	B 1.250; thread L 1.094	—	—	—	—	letters as printed; weight (carbon steel) 8.64 lb
square head plug, Penn Machine (in)	5	—	A 3.250	C 1.625	B 1.875; thread L 1.187	—	—	—	—	letters as printed; weight (carbon steel) 17.12 lb
square head plug, Penn Machine (in)	6	—	A 4.250	C 1.875	B 2.000; thread L 1.208	—	—	—	—	letters as printed; weight (carbon steel) 28.41 lb
square head plug, ASME B16.11 (wermac, mm)	1/2	—	B min 14	C min 10	E min length 14	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	3/4	—	B min 16	C min 11	E min length 16	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	1	—	B min 21	C min 13	E min length 19	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	1-1/4	—	B min 24	C min 14	E min length 21	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	1-1/2	—	B min 28	C min 16	E min length 21	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	2	—	B min 32	C min 18	E min length 22	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	2-1/2	—	B min 36	C min 19	E min length 27	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	3	—	B min 41	C min 21	E min length 28	—	—	—	—	wermac letters: B across flats, C square height, E length
square head plug, ASME B16.11 (wermac, mm)	4	—	B min 65	C min 25	E min length 32	—	—	—	—	wermac letters: B across flats, C square height, E length
hex head plug, ASME B16.11 (wermac, mm)	1/2	—	F nominal 22	J min 8	E min length 14	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	3/4	—	F nominal 27	J min 10	E min length 16	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	1	—	F nominal 35	J min 10	E min length 19	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	1-1/4	—	F nominal 44.5	J min 14	E min length 21	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	1-1/2	—	F nominal 51	J min 16	E min length 21	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	2	—	F nominal 63.5	J min 18	E min length 22	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	2-1/2	—	F nominal 76	J min 19	E min length 27	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	3	—	F nominal 89	J min 21	E min length 28	—	—	—	—	wermac letters; F read as the hex width
hex head plug, ASME B16.11 (wermac, mm)	4	—	F nominal 117.5	J min 25	E min length 32	—	—	—	—	wermac letters; F read as the hex width
round head plug, ASME B16.11 (wermac, mm)	1/2	—	D head dia 21	—	E min length 14; A min length 44	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	3/4	—	D head dia 27	—	E min length 16; A min length 44	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	1	—	D head dia 33	—	E min length 19; A min length 51	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	1-1/4	—	D head dia 43	—	E min length 21; A min length 51	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	1-1/2	—	D head dia 48	—	E min length 21; A min length 51	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	2	—	D head dia 60	—	E min length 22; A min length 64	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	2-1/2	—	D head dia 73	—	E min length 37; A min length 70	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	3	—	D head dia 89	—	E min length 28; A min length 70	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
round head plug, ASME B16.11 (wermac, mm)	4	—	D head dia 114	—	E min length 32; A min length 76	—	—	—	—	wermac prints E = 37 at 2-1/2, against 27 for hex / square: probably a typo
hex socket plug, Dryseal NPTF (Alma, in)	1/16	27	OD D 0.312	J 5/32	L 0.300 – 0.324	T min 0.140	G min 0.062	150 in-lb	15/64	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	1/8	27	OD D 0.405	J 3/16	L 0.300 – 0.324	T min 0.140	G min 0.062	250 in-lb	21/64	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	1/4	18	OD D 0.540	J 1/4	L 0.417 – 0.457	T min 0.218	G min 0.073	600 in-lb	27/64	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	3/8	18	OD D 0.675	J 5/16	L 0.480 – 0.520	T min 0.250	G min 0.084	1200 in-lb	7/16	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	1/2	14	OD D 0.840	J 3/8	L 0.542 – 0.582	T min 0.312	G min 0.095	1800 in-lb	9/16	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	3/4	14	OD D 1.050	J 9/16	L 0.605 – 0.645	T min 0.312	G min 0.125	3000 in-lb	57/64	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	1	11-1/2	OD D 1.315	J 5/8	L 0.730 – 0.770	T min 0.375	G min 0.125	4200 in-lb	1-1/8	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	1-1/4	11-1/2	OD D 1.660	J 3/4	L 0.792 – 0.832	T min 0.437	G min 0.156	5400 in-lb	37.5 mm	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	1-1/2	11-1/2	OD D 1.900	J 1	L 0.780 – 0.843	T min 0.437	G min 0.156	6900 in-lb	43.5 mm	letters as printed by Alma (L, G not defined)
hex socket plug, Dryseal NPTF (Alma, in)	2	11-1/2	OD D 2.375	J 1	L 0.844 – 0.906	T min 0.437	G min 0.156	8500 in-lb	2-3/16	letters as printed by Alma (L, G not defined)
hex socket plug, flush PTF (Alma, American Fastener, in)	1/16	27	OD D 0.307	J 5/32	L 0.235 – 0.250	T min 0.140	G min 0.052	150 in-lb	15/64	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	1/8	27	OD D 0.401	J 3/16	L 0.235 – 0.250	T min 0.140	G min 0.049	250 in-lb	21/64	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	1/4	18	OD D 0.529	J 1/4	L 0.391 – 0.406	T min 0.218	G min 0.045	600 in-lb	27/64	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	3/8	18	OD D 0.667	J 5/16	L 0.391 – 0.406	T min 0.250	G min 0.040	1200 in-lb	9/16	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	1/2	14	OD D 0.830	J 3/8	L 0.516 – 0.531	T min 0.312	G min 0.067	1800 in-lb	9/16	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	3/4	14	OD D 1.041	J 9/16	L 0.516 – 0.531	T min 0.312	G min 0.054	3000 in-lb	57/64	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	1	11-1/2	OD D 1.302	J 5/8	L 0.641 – 0.656	T min 0.375	G min 0.112	4200 in-lb	1-1/8	same numbers on both sheets
hex socket plug, flush PTF (Alma, American Fastener, in)	1-1/4	11-1/2	OD D 1.647	J 3/4	L 0.641 – 0.656	T min 0.437	G min 0.102	5400 in-lb	37.5 mm	same numbers on both sheets

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits as drawn.

feature	exact	mates with	fit	files
hex socket	J across flats: 1/16 5/32, 1/8 3/16, 1/4 1/4, 3/8 5/16, 1/2 3/8, 3/4 9/16, 1 5/8, 1-1/4 3/4, 1-1/2 and 2 in 1 in; depth T min 0.140 to 0.437 in	hex key (Allen key) of the same size	socket	hex-socket-plug-*
thread (tapered; OD as plain cylinder)	OD D: Dryseal NPTF 1/16 0.312 … 2 in 2.375 in; flush PTF 1/16 0.307 … 1-1/4 1.647 in	tapped hole: tap drill per Alma 1/16 15/64, 1/8 21/64, 1/4 27/64, 3/8 7/16 (Dryseal) or 9/16 (flush), 1/2 9/16, 3/4 57/64, 1 1-1/8 in	designed	hex-socket-plug-*

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Pennsylvania Machine Works (Penn Machine)	Forged steel square head plug: pipe size 1/8 to 6, dimensions A, B, C, weight and thread length L, inches	web	Maker catalog; numbers only. Letters A / B / C are not defined in the text read
wermac.org	Threaded plugs (ASME B16.11): hex head, square head and round head plug dimensions in mm, NPS 1/2 to 4	web	Third-party reference; numbers only. No hex-socket table on the page
Alma Bolt	Hex socket pressure plugs: Dryseal NPTF (1/16 to 2) and flush PTF (1/16 to 1-1/4): D, TPI, J hex socket, T key engagement, G wall, L max / min, torque, tap drill	web	Distributor catalog; numbers only. The page does not define the L and G letters
American Fastener	Socket pipe plug, flush seal: nominal size, OD, TPI, hex socket size, key engagement, wall, overall length max / min, tightening torque, 1/16 to 1-1/4	web	Maker data sheet; numbers only. No standard cited
McMaster-Carr	SAE J531 pipe plugs (free STEP/IGES per part, for your own design use; no redistribution)	STEP, IGES, PDF	McMaster-Carr site terms: personal design use, no redistribution verify
McMaster-Carr	Steel socket pipe fitting plugs (free STEP/IGES per part, for your own design use; no redistribution)	STEP, IGES, PDF	McMaster-Carr site terms: personal design use, no redistribution verify

Free files

★ Free files 18 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

hex-socket-plug-nptf-1-16-envelope	1/16 Dryseal NPTF hex socket plug envelope: straight cylinder Ø7.92 mm (OD D 0.312 in) × 8.23 mm (L max 0.324 in), 5/32 in (3.97 mm) hex socket 3.56 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-1-8-envelope	1/8 Dryseal NPTF hex socket plug envelope: straight cylinder Ø10.29 mm (OD D 0.405 in) × 8.23 mm (L max 0.324 in), 3/16 in (4.76 mm) hex socket 3.56 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-1-4-envelope	1/4 Dryseal NPTF hex socket plug envelope: straight cylinder Ø13.72 mm (OD D 0.540 in) × 11.61 mm (L max 0.457 in), 1/4 in (6.35 mm) hex socket 5.54 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-3-8-envelope	3/8 Dryseal NPTF hex socket plug envelope: straight cylinder Ø17.14 mm (OD D 0.675 in) × 13.21 mm (L max 0.520 in), 5/16 in (7.94 mm) hex socket 6.35 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-1-2-envelope	1/2 Dryseal NPTF hex socket plug envelope: straight cylinder Ø21.34 mm (OD D 0.840 in) × 14.78 mm (L max 0.582 in), 3/8 in (9.52 mm) hex socket 7.92 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-3-4-envelope	3/4 Dryseal NPTF hex socket plug envelope: straight cylinder Ø26.67 mm (OD D 1.050 in) × 16.38 mm (L max 0.645 in), 9/16 in (14.29 mm) hex socket 7.92 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-1-envelope	1 Dryseal NPTF hex socket plug envelope: straight cylinder Ø33.40 mm (OD D 1.315 in) × 19.56 mm (L max 0.770 in), 5/8 in (15.88 mm) hex socket 9.52 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-1-1-4-envelope	1-1/4 Dryseal NPTF hex socket plug envelope: straight cylinder Ø42.16 mm (OD D 1.660 in) × 21.13 mm (L max 0.832 in), 3/4 in (19.05 mm) hex socket 11.10 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-1-1-2-envelope	1-1/2 Dryseal NPTF hex socket plug envelope: straight cylinder Ø48.26 mm (OD D 1.900 in) × 21.41 mm (L max 0.843 in), 1 in (25.40 mm) hex socket 11.10 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-nptf-2-envelope	2 Dryseal NPTF hex socket plug envelope: straight cylinder Ø60.32 mm (OD D 2.375 in) × 23.01 mm (L max 0.906 in), 1 in (25.40 mm) hex socket 11.10 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-1-16-envelope	1/16 flush-seal PTF hex socket plug envelope: straight cylinder Ø7.80 mm (OD D 0.307 in) × 6.35 mm (L max 0.250 in), 5/32 in (3.97 mm) hex socket 3.56 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-1-8-envelope	1/8 flush-seal PTF hex socket plug envelope: straight cylinder Ø10.19 mm (OD D 0.401 in) × 6.35 mm (L max 0.250 in), 3/16 in (4.76 mm) hex socket 3.56 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-1-4-envelope	1/4 flush-seal PTF hex socket plug envelope: straight cylinder Ø13.44 mm (OD D 0.529 in) × 10.31 mm (L max 0.406 in), 1/4 in (6.35 mm) hex socket 5.54 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-3-8-envelope	3/8 flush-seal PTF hex socket plug envelope: straight cylinder Ø16.94 mm (OD D 0.667 in) × 10.31 mm (L max 0.406 in), 5/16 in (7.94 mm) hex socket 6.35 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-1-2-envelope	1/2 flush-seal PTF hex socket plug envelope: straight cylinder Ø21.08 mm (OD D 0.830 in) × 13.49 mm (L max 0.531 in), 3/8 in (9.52 mm) hex socket 7.92 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-3-4-envelope	3/4 flush-seal PTF hex socket plug envelope: straight cylinder Ø26.44 mm (OD D 1.041 in) × 13.49 mm (L max 0.531 in), 9/16 in (14.29 mm) hex socket 7.92 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-1-envelope	1 flush-seal PTF hex socket plug envelope: straight cylinder Ø33.07 mm (OD D 1.302 in) × 16.66 mm (L max 0.656 in), 5/8 in (15.88 mm) hex socket 9.52 mm deep (T min); taper thread not drawn	STEP · STL
hex-socket-plug-flush-ptf-1-1-4-envelope	1-1/4 flush-seal PTF hex socket plug envelope: straight cylinder Ø41.83 mm (OD D 1.647 in) × 16.66 mm (L max 0.656 in), 3/4 in (19.05 mm) hex socket 11.10 mm deep (T min); taper thread not drawn	STEP · STL

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Plain text: sheet.txt · JSON: /api/geometry?object=pipe-plugs-npt-square-hex-socket

NPT pipe plugs: square head, hex head, round head and hex socket (ASME B16.11; Dryseal NPTF, flush PTF) 1/16 to 6 in — head size, length, socket + envelope models, isometric render of a generated part — Render of hex-socket-plug-nptf-2-envelope from the free STEP; not to scale.

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NPT male thread envelopes 1/8 to 1 in (ASME B1.20.1)6 sizes★ 6 files Free

Forged threaded fittings (ASME B16.11), Class 2000 / 3000 / 6000: elbows, tees, caps — centre-to-end, band OD, thread length, isometric render of a generated part

Forged threaded fittings (ASME B16.11), Class 2000 / 3000 / 6000: elbows, tees, caps — centre-to-end, band OD, thread length59 sizes★ 13 files Free

Forged socket-weld fittings (ASME B16.11), Class 3000 and 6000: elbows, tees, couplings — socket bore, depth, centre-to-bottom, isometric render of a generated part

Forged socket-weld fittings (ASME B16.11), Class 3000 and 6000: elbows, tees, couplings — socket bore, depth, centre-to-bottom15 sizes★ 14 files Free

Malleable iron threaded fittings, Class 150 (ASME B16.3): elbow, tee, coupling and union dimensions, NPS 1/8 to 6, isometric render of a generated part

Malleable iron threaded fittings, Class 150 (ASME B16.3): elbow, tee, coupling and union dimensions, NPS 1/8 to 616 sizes★ 8 files Free

Hex keys (Allen keys): ISO 2936 metric 0.7–36 mm and ASME B18.3 inch .050–7/8 in: across flats, across corners, long and short arm + 31 key models, isometric render of a generated part

Hex keys (Allen keys): ISO 2936 metric 0.7–36 mm and ASME B18.3 inch .050–7/8 in: across flats, across corners, long and short arm + 31 key models184.1×54.0×21.8 mm★ 31 files Free

Schedule 40 pipe and PVC fittings, 1/2 to 2 inch, isometric render of a generated part

Schedule 40 pipe and PVC fittings, 1/2 to 2 inch6 sizes★ 6 files Free

Tri-clamp × male NPT adapters (21MP style): ½ to 4 in, isometric render of a generated part

Tri-clamp × male NPT adapters (21MP style): ½ to 4 in10 sizes★ 10 files

Questions

What Allen key fits a 1/4 NPT socket plug?

1/4 in across flats (J), key engagement 0.218 in min, in both Alma's Dryseal and flush-PTF tables; 1/8 NPT takes a 3/16 in key and 3/8 NPT a 5/16 in key.

What is the tap drill for a 1/8 NPT plug?

21/64 in in Alma's tables for both the Dryseal and flush series; the OD of the plug is 0.405 in (Dryseal) or 0.401 in (flush).

How big is a 1/2 NPT square head plug?

About 9/16 in (0.563) across flats and 0.380 in high in Penn's catalog, 14 mm across flats and 10 mm high in wermac's B16.11 table, 0.534 in of thread (Penn L).