Butt-weld 3D (3R) elbows, 90° and 45° (ASME B16.9), NPS 3/4 to 12: centre-to-end 3 × NPS — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/butt-weld-elbows-3d/ (sheet CC BY 4.0) Basis: Centre-to-end A (90°) and B (45°) in mm from Wermac's ASME B16.9 3D table; the 90° value cross-checked against Texas Flange's 3R inch table; OD and Sch 40 wall per ASME B36.10 Catalog version: 2026-10-20 Sizes: see table below - A 3D elbow (also called 3R) turns on a centreline radius of 3 × the nominal pipe size: for a 90° elbow centre-to-end A equals the bend radius, 3.00 in at NPS 1 (76 mm) and 6.00 in at NPS 2 (152 mm). Texas Flange: 'A 3R elbow turns on a centreline radius of three times the nominal pipe diameter'. Wermac's mm column and Texas Flange's inch column agree for every size from NPS 3/4 to 12. - The 45° centre-to-end B is Wermac's mm table only; no second source for the 45° 3D value was read. Wermac prints no NPS 1/2 row for 3D. B is close to, but not exactly, R × tan 22.5° (NPS 1: 31 printed vs 31.6 from the radius), so no 45° file is drawn: the table value and a pure circular arc would disagree. - Files: the 90° 3D elbow at NPS 1, 2 and 4, Schedule 40, hollow: a torus section with bend radius equal to the published centre-to-end (3 × NPS), so the faces sit exactly A from the intersection of the pipe axes. - Long radius (1.5 × NPS) is butt-weld-elbows-long-radius, short radius (1 × NPS) is butt-weld-elbows-short-radius. - 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. NPS OD, mm 90° 3D centre-to-end A, mm (Wermac) 90° 3D centre-to-end, in (Texas Flange) 45° 3D centre-to-end B, mm (Wermac) Sch 40 wall 3/4 26.7 (1.05 in) 57 2.25 24 0.113 in (2.87 mm) 1 33.4 (1.32 in) 76 3.00 31 0.133 in (3.38 mm) 1-1/4 42.2 (1.66 in) 95 3.75 39 0.140 in (3.56 mm) 1-1/2 48.3 (1.90 in) 114 4.50 47 0.145 in (3.68 mm) 2 60.3 (2.38 in) 152 6.00 63 0.154 in (3.91 mm) 2-1/2 73.0 (2.88 in) 190 7.50 79 0.203 in (5.16 mm) 3 88.9 (3.50 in) 229 9.00 95 0.216 in (5.49 mm) 3-1/2 101.6 (4.00 in) 267 10.50 111 0.226 in (5.74 mm) 4 114.3 (4.50 in) 305 12.00 127 0.237 in (6.02 mm) 5 141.3 (5.56 in) 381 15.00 157 0.258 in (6.55 mm) 6 168.3 (6.62 in) 457 18.00 189 0.280 in (7.11 mm) 8 219.1 (8.62 in) 610 24.00 252 0.322 in (8.18 mm) 10 273.0 (10.75 in) 762 30.00 316 0.365 in (9.27 mm) 12 323.8 (12.75 in) 914 36.00 378 0.406 in (10.31 mm) Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Wermac: ASME B16.9 long radius, 3D and 45 deg elbow dimensions (mm) — web — Publisher's page; dimensions are facts — https://wermac.org/fittings/dim_elbows_a.html - Texas Flange (manufacturer / distributor): Butt-weld 90 deg 3R elbows: OD and centre-to-end by NPS — web — Publisher's page; dimensions are facts — https://texasflange.com/butt-weld-fittings/elbow-90-3r/ - 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 license at link] — https://www.mcmaster.com/products/metal-pipe-fittings/ Free files (CC BY 4.0, Xem Studio; STEP + STL, 3 parts): https://xemstudio.com/files/hardware/butt-weld-elbows-3d/index.json API: https://xemstudio.com/api/geometry?object=butt-weld-elbows-3d