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Butt-weld short-radius 90° elbows (ASME B16.9 / B16.28), NPS 1 to 12: centre-to-end = 1 × NPS

Name: Butt-weld short-radius 90° elbows (ASME B16.9 / B16.28), NPS 1 to 12: centre-to-end = 1 × NPS dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

What is the centre-to-end of a short-radius (SR) 90° butt-weld elbow, and how does it differ from long radius? · Standard part · basis: Centre-to-end A (mm) from Wermac's ASME B16.9 short-radius table, cross-checked with Texas Flange's inch table; OD and Schedule 40 wall per ASME B36.10 (Texas Flange)

Also called: short radius elbow dimensions, sr elbow center to end, 90 degree short radius elbow, butt weld short radius elbow, b16.28 elbow, 1d elbow dimensions, sr 90 elbow step file, short radius elbow vs long radius, weld elbow 1d radius, short radius elbow cad, 2 inch sr elbow dimensions, sch 40 short radius elbow

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

sizes: 13 in table

Notes

A short-radius (SR) elbow turns on a bend radius of 1 × NPS, so centre-to-end A equals the nominal size in inches (NPS 2 = 2.00 in = 51 mm). A long-radius (LR) elbow turns on 1.5 × NPS (see butt-weld-elbows-long-radius) and a 3D elbow on 3 × NPS (butt-weld-elbows-3d). Short radius starts at NPS 1 in the tables read; there is no NPS 1/2 or 3/4 short-radius row.
Both sources agree: the inch value (Texas Flange) times 25.4 matches Wermac's mm value within rounding for every size (for example NPS 4: 4.00 in = 101.6 mm, printed 102 mm). The mm column is the standard's rounded metric figure; the inch column is the exact bend radius. Texas Flange notes that OD and A are the same for every schedule: only the wall changes.
Wermac prints the manufacturing tolerance on A as ±2 mm for NPS 1/2 to 24 and on OD at the bevel as +1.6 / −0.8 mm for NPS 1/2 to 2-1/2, ±1.6 mm for NPS 3 to 4, +2.4 / −1.6 mm for NPS 5 to 8 and +4 / −3.2 mm for NPS 10 to 18. Wall: not less than 87.5% of the nominal wall.
Files at NPS 1, 2 and 4, Schedule 40, hollow: a torus section of the pipe's OD and wall, bend radius equal to the published centre-to-end (inch value × 25.4), so the end faces sit exactly A from the intersection of the two pipe axes. This is the full shape: a circular bend is defined by A, OD and wall.
OD and Schedule 40 wall: the tables print OD rounded (1.32, 2.38, 4.50 in); the files use the exact ASME B36.10 OD (1.315, 2.375, 4.500 in) with the Sch 40 wall (.133, .154, .237 in) that Texas Flange prints for each size. Fittings are made to match the pipe's OD and wall.
Ends are drawn square. Real fittings are bevelled for welding to ASME B16.25; no public, citable statement of the bevel was found, so it is not drawn.
Heavier schedules change only the wall: use the OD from the table and a wall from the pipe schedule (Sch 80 NPS 2 is 0.218 in, Sch 80 NPS 4 0.337 in).

Butt-weld short-radius 90° elbows (ASME B16.9 / B16.28), NPS 1 to… size chart

NPS	OD, mm	centre-to-end A, mm (Wermac)	centre-to-end A, in (Texas Flange)	Sch 40 wall
1	33.4 (1.32 in)	25	1.00	0.133 in (3.38 mm)
1-1/4	42.2 (1.66 in)	32	1.25	0.140 in (3.56 mm)
1-1/2	48.3 (1.90 in)	38	1.50	0.145 in (3.68 mm)
2	60.3 (2.38 in)	51	2.00	0.154 in (3.91 mm)
2-1/2	73.0 (2.88 in)	64	2.50	0.203 in (5.16 mm)
3	88.9 (3.50 in)	76	3.00	0.216 in (5.49 mm)
3-1/2	101.6 (4.00 in)	89	3.50	0.226 in (5.74 mm)
4	114.3 (4.50 in)	102	4.00	0.237 in (6.02 mm)
5	141.3 (5.56 in)	127	5.00	0.258 in (6.55 mm)
6	168.3 (6.62 in)	152	6.00	0.280 in (7.11 mm)
8	219.1 (8.62 in)	203	8.00	0.322 in (8.18 mm)
10	273.0 (10.75 in)	254	10.00	0.365 in (9.27 mm)
12	323.8 (12.75 in)	305	12.00	0.406 in (10.31 mm)

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
weld ends	OD = pipe OD (Ø33.40 / Ø60.33 / Ø114.30 at NPS 1 / 2 / 4), wall = Sch 40 (3.38 / 3.91 / 6.02)	Schedule 40 pipe of the same NPS, butt-welded (schedule-40-pipe)	designed	bw-elbow-90-sr*
centre-to-end A	25.4 / 50.8 / 101.6 (= 1 × NPS in)	pipe run set-back: face-to-axis distance of the next fitting or flange	designed	bw-elbow-90-sr*

Where the files are

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

Wermac	ASME B16.9 90 deg short-radius elbow dimensions and tolerances (mm)	web	Publisher's page; dimensions are facts
Texas Flange (manufacturer / distributor)	Butt-weld 90 deg short-radius elbows (ASME B16.28): OD and centre-to-end by NPS, all schedules	web	Publisher's page; dimensions are facts
McMaster-Carr	Metal pipe fittings (butt-weld elbows, tees, reducers, caps) (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 3 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

bw-elbow-90-sr-nps1-sch40	NPS 1 Sch 40 short-radius 90° elbow: OD 33.40 × 3.38 wall, bend radius = centre-to-end 25.4 mm; ends square	STEP · STL
bw-elbow-90-sr-nps2-sch40	NPS 2 Sch 40 short-radius 90° elbow: OD 60.32 × 3.91 wall, bend radius = centre-to-end 50.8 mm; ends square	STEP · STL
bw-elbow-90-sr-nps4-sch40	NPS 4 Sch 40 short-radius 90° elbow: OD 114.30 × 6.02 wall, bend radius = centre-to-end 101.6 mm; ends square	STEP · STL

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Plain text: sheet.txt · JSON: /api/geometry?object=butt-weld-elbows-short-radius