Pipe Elbows
NUMET ALLOYS engineers and manufactures high-performance pipe elbows designed to alter the direction of fluid flow with minimal pressure drop and turbulence. Available in precise 45°, 90°, and 180° configurations, our elbows are precision-beveled for flawless welding and forged to withstand severe mechanical and thermal stress in critical piping systems.
Detailed Technical Specifications
Bend Radius: Long Radius (LR = 1.5D), Short Radius (SR = 1.0D), 3D, 5D, Custom Sweep Bends
Stainless Steel: ASTM A403 WP304/304L, WP316/316L, WP321, WP347
Alloy Steel: ASTM A234 WP1, WP5, WP9, WP11, WP22, WP91
Welded (ERW/SAW): 24" NB to 48" NB (100% X-Ray Tested)
Dimensions (ASME B16.9 & B16.28)
Long radius elbows have a centreline radius of 1.5 times the nominal pipe size and are the default choice for most piping; short radius elbows use a 1.0D radius for tight routing. Centre-to-end dimensions below are nominal values from the standards. Note that the 45° dimension is not half the 90° dimension — it is set by the tangent of half the bend angle.
90° and 45° Long Radius Elbows (Radius = 1.5D)
ASME B16.9| SizeNPS | Outside Dia.mm | Outside Dia.inch | 90° Centre-to-End Amm | 90° Ainch | 45° Centre-to-End Bmm | 45° Binch |
|---|---|---|---|---|---|---|
| 1/2 | 21.3 | 0.840 | 38 | 1.50 | 16 | 0.62 |
| 3/4 | 26.7 | 1.050 | 38 | 1.50 | 19 | 0.75 |
| 1 | 33.4 | 1.315 | 38 | 1.50 | 22 | 0.88 |
| 1-1/4 | 42.2 | 1.660 | 48 | 1.88 | 25 | 1.00 |
| 1-1/2 | 48.3 | 1.900 | 57 | 2.25 | 29 | 1.12 |
| 2 | 60.3 | 2.375 | 76 | 3.00 | 35 | 1.38 |
| 2-1/2 | 73.0 | 2.875 | 95 | 3.75 | 44 | 1.75 |
| 3 | 88.9 | 3.500 | 114 | 4.50 | 51 | 2.00 |
| 3-1/2 | 101.6 | 4.000 | 133 | 5.25 | 57 | 2.25 |
| 4 | 114.3 | 4.500 | 152 | 6.00 | 64 | 2.50 |
| 5 | 141.3 | 5.563 | 190 | 7.50 | 79 | 3.12 |
| 6 | 168.3 | 6.625 | 229 | 9.00 | 95 | 3.75 |
| 8 | 219.1 | 8.625 | 305 | 12.00 | 127 | 5.00 |
| 10 | 273.1 | 10.750 | 381 | 15.00 | 159 | 6.25 |
| 12 | 323.9 | 12.750 | 457 | 18.00 | 190 | 7.50 |
| 14 | 355.6 | 14.000 | 533 | 21.00 | 222 | 8.75 |
| 16 | 406.4 | 16.000 | 610 | 24.00 | 254 | 10.00 |
| 18 | 457.2 | 18.000 | 686 | 27.00 | 286 | 11.25 |
| 20 | 508.0 | 20.000 | 762 | 30.00 | 318 | 12.50 |
| 22 | 558.8 | 22.000 | 838 | 33.00 | 343 | 13.50 |
| 24 | 609.6 | 24.000 | 914 | 36.00 | 381 | 15.00 |
Long radius elbows are tabulated in ASME B16.9 from NPS 1/2 up to NPS 48; sizes above NPS 24 are made to order.
90° Short Radius Elbows (Radius = 1.0D)
ASME B16.28| SizeNPS | Outside Dia.mm | Centre-to-End Amm | Centre-to-End Ainch |
|---|---|---|---|
| 1/2 | 21.3 | — | — |
| 3/4 | 26.7 | — | — |
| 1 | 33.4 | 25 | 1.00 |
| 1-1/4 | 42.2 | 32 | 1.25 |
| 1-1/2 | 48.3 | 38 | 1.50 |
| 2 | 60.3 | 51 | 2.00 |
| 2-1/2 | 73.0 | 64 | 2.50 |
| 3 | 88.9 | 76 | 3.00 |
| 3-1/2 | 101.6 | 89 | 3.50 |
| 4 | 114.3 | 102 | 4.00 |
| 5 | 141.3 | 127 | 5.00 |
| 6 | 168.3 | 152 | 6.00 |
| 8 | 219.1 | 203 | 8.00 |
| 10 | 273.1 | 254 | 10.00 |
| 12 | 323.9 | 305 | 12.00 |
| 14 | 355.6 | 356 | 14.00 |
| 16 | 406.4 | 406 | 16.00 |
| 18 | 457.2 | 457 | 18.00 |
| 20 | 508.0 | 508 | 20.00 |
| 22 | 558.8 | 559 | 22.00 |
| 24 | 609.6 | 610 | 24.00 |
Short radius centre-to-end equals the nominal size in inches. ASME B16.28 dimension tables begin at NPS 1 — NPS 1/2 and 3/4 short radius elbows are supplied by agreement.
180° Returns — Long and Short Radius
ASME B16.9 / B16.28| SizeNPS | LR Centre-to-Centre Omm | LR Oinch | LR Back-to-Face Kmm | LR Kinch | SR Centre-to-Centre Omm | SR Back-to-Face Kmm |
|---|---|---|---|---|---|---|
| 1/2 | 76 | 3.00 | 48 | 1.88 | — | — |
| 3/4 | 76 | 3.00 | 51 | 2.00 | — | — |
| 1 | 76 | 3.00 | 56 | 2.19 | 51 | 41 |
| 1-1/4 | 95 | 3.75 | 70 | 2.75 | 64 | 52 |
| 1-1/2 | 114 | 4.50 | 83 | 3.25 | 76 | 62 |
| 2 | 152 | 6.00 | 106 | 4.19 | 102 | 81 |
| 2-1/2 | 190 | 7.50 | 132 | 5.19 | 127 | 100 |
| 3 | 229 | 9.00 | 159 | 6.25 | 152 | 121 |
| 3-1/2 | 267 | 10.50 | 184 | 7.25 | 178 | 140 |
| 4 | 305 | 12.00 | 210 | 8.25 | 203 | 159 |
| 5 | 381 | 15.00 | 262 | 10.31 | 254 | 197 |
| 6 | 457 | 18.00 | 313 | 12.31 | 305 | 237 |
| 8 | 610 | 24.00 | 414 | 16.31 | 406 | 313 |
| 10 | 762 | 30.00 | 518 | 20.38 | 508 | 391 |
| 12 | 914 | 36.00 | 619 | 24.38 | 610 | 467 |
| 14 | 1067 | 42.00 | 711 | 28.00 | 711 | 533 |
| 16 | 1219 | 48.00 | 813 | 32.00 | 813 | 610 |
| 18 | 1372 | 54.00 | 914 | 36.00 | 914 | 686 |
| 20 | 1524 | 60.00 | 1016 | 40.00 | 1016 | 762 |
| 22 | 1676 | 66.00 | 1118 | 44.00 | 1118 | 838 |
| 24 | 1829 | 72.00 | 1219 | 48.00 | 1219 | 914 |
180° returns are tabulated only up to NPS 24. For NPS 1/2 to 1 the long radius centre-to-centre holds at the standard minimum of 76 mm (3.00") rather than following 3D. Short radius returns begin at NPS 1.
Dimensions are nominal values from the referenced standard and are shown for reference only; tolerances apply as specified in the standard. Sizes above 24" NB and non-standard combinations are manufactured to order. For certified drawings against your line list, contact our technical team.
Core Advantages
Optimized Flow Dynamics
Engineered with perfectly smooth inner radii to minimize turbulence, reduce pressure drops, and maintain efficient fluid velocity.
Uniform Wall Thickness
Advanced mandrel forming processes ensure zero material thinning at the extrados (outer curve), guaranteeing structural integrity.
Superior Weldability
Precision machine-beveled ends (conforming to ASME B16.25) provide flawless joint preparation for high-strength butt welding.