Butt-weld elbow dimensions: ASME B16.9 and EN 10253-1
Centre-to-end dimensions of our 90° and 45° elbows, in both standards we make, with wall and weight. The chart to keep at hand for a drawing or a take-off.
Reading an elbow’s dimensions
An elbow’s take-off is the distance from the bend centre to the plane of each end. ASME B16.9 calls it A for a 90° and B for a 45°; our EN 10253-1 sheets call it F. To place an elbow on a drawing, measure this dimension from the pipe axis.
ASME B16.9 long radius (1.5D) elbows
The bend radius is one and a half times the nominal size. These elbows are made in A234 WPB, seamless or welded depending on the size, and delivered painted.
| NPS | OD D (mm) | 90° elbow, A (mm) | 45° elbow, B (mm) |
|---|---|---|---|
| ½" | 21.3 | 38 | 16 |
| ¾" | 26.7 | 38 | 19 |
| 1" | 33.4 | 38 | 22 |
| 1¼" | 42.2 | 48 | 25 |
| 1½" | 48.3 | 57 | 29 |
| 2" | 60.3 | 76 | 35 |
| 2½" | 73.0 | 95 | 44 |
| 3" | 88.9 | 114 | 51 |
| 4" | 114.3 | 152 | 64 |
| 5" | 141.3 | 190 | 79 |
| 6" | 168.3 | 229 | 95 |
| 8" | 219.1 | 305 | 127 |
| 10" | 273.0 | 381 | 159 |
| 12" | 323.8 | 457 | 190 |
Long radius (1.5D) elbows to ASME B16.9: A and B are centre-to-end. Tolerance ± 2 mm.
EN 10253-1 type 3D 90° elbows
European elbows are specified by outside diameter and wall, in S235, black or galvanized. The chart follows our plant sheet, with the usual wall and its weight.
| NPS | OD D (mm) | F (mm) | Wall T (mm) | Weight (kg) |
|---|---|---|---|---|
| ½" | 21.3 | 29 | 2.0 | 0.04 |
| ¾" | 26.9 | 29 | 2.3 | 0.06 |
| 1" | 33.7 | 38 | 2.6 | 0.12 |
| 1¼" | 42.4 | 48 | 2.6 | 0.19 |
| 1½" | 48.3 | 57 | 2.6 | 0.26 |
| 2" | 60.3 | 76 | 2.9 | 0.49 |
| 2½" | 76.1 | 95 | 2.9 | 0.78 |
| 3" | 88.9 | 114 | 3.2 | 1.22 |
| 4" | 114.3 | 152 | 3.6 | 2.35 |
| 5" | 139.7 | 190 | 4.0 | 4.01 |
| 6" | 168.3 | 229 | 4.5 | 6.53 |
| 8" | 219.1 | 305 | 6.3 | 15.96 |
| 10" | 273.0 | 381 | 6.3 | 24.80 |
| 12" | 323.9 | 457 | 7.1 | 39.82 |
90° type 3D elbows to EN 10253-1, in S235: F is centre-to-face. Indicative weights for wall T.
The EN 10253 "3D" does not mean three times the outside diameter: at 114.3, the type 3D elbow measures 152 mm, like the 4" ASME long radius elbow.
Comparing the two standards
From 1" up, the 90° dimension is the same in both standards: 38, 48, 57, 76, 95, 114, 152 mm and so on up to 457 mm at 12". The two smallest sizes differ: at ½" and ¾", the EN 10253-1 elbow measures 29 mm and the ASME one 38 mm. Outside diameters also differ for several sizes (26.9 versus 26.7, 33.7 versus 33.4, 76.1 versus 73.0…): an elbow is ordered in the diameter series of the pipe.
ASME B16.9 tolerances
| NPS | OD at bevel | ID at end | Centre-to-end LR elbows, tees | Centre-to-end 3D elbows | Cap length |
|---|---|---|---|---|---|
| ½ – 2½ | +1.6 / −0.8 | ± 0.8 | ± 2 | ± 3 | ± 3 |
| 3 – 3½ | ± 1.6 | ± 1.6 | ± 2 | ± 3 | ± 3 |
| 4 | ± 1.6 | ± 1.6 | ± 2 | ± 3 | ± 3 |
| 5 – 8 | +2.4 / −1.6 | ± 1.6 | ± 2 | ± 3 | ± 6 |
| 10 – 18 | +4.0 / −3.2 | ± 3.2 | ± 2 | ± 3 | ± 6 |
Tolerances in mm to ASME B16.9. Wall: at least 87.5% of nominal at any point.
Dimensions by size
90° elbows
45° elbows
Standards
- ASME B16.9: factory-made wrought buttwelding fittings.
- EN 10253-1: butt-welding pipe fittings, wrought carbon steel for general use.
Frequently asked questions
What is an elbow’s centre-to-end?
The distance from the bend centre to the plane of an end (A for a 90°, B for a 45° in ASME B16.9, F in EN 10253-1).
What is the difference between a 1.5D and a 3D elbow?
The 1.5D is the ASME B16.9 long radius elbow; type 3D is its EN 10253-1 name. From 1" up, their 90° dimensions are identical.
What is the centre-to-end of a 4" 90° elbow?
152 mm, to ASME B16.9 (114.3 mm) as to EN 10253-1 (114.3 mm).
Do you have the EN 10253-1 45° elbow dimensions?
Yes, we send them on request with your quote.
Other charts
Butt-weld equal tee dimensions: ASME B16.9 and EN 10253-1On an equal tee, the centre-to-end is the same on all three outlets.
Butt-weld reducer dimensions: ASME B16.9 and EN 10253-1Under ASME B16.9, length H depends on the large end only: 102 mm for any 4" reducer.
Butt-weld cap and dished end dimensions: ASME B16.9 and EN 10253-1ASME B16.9 caps measure 25 mm (½") to 102 mm (8"); above a limiting wall the length becomes E1.