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ConsumablesFlange, elbow and pipe size charts.
The dimensions fitters and buyers look up most, on one page: DN–inch equivalents, outside diameters, long-radius elbow dimensions and flange drilling.
DN – inch – pipe outside diameter
Nominal size (DN), inch equivalent and pipe outside diameter. A few sizes differ between the European (EN) and American (ASME) series.
| DN | Inch | OD EN | OD ASME |
|---|---|---|---|
| DN15 | 1/2" | 21.3 | 21.3 |
| DN20 | 3/4" | 26.9 | 26.7 |
| DN25 | 1" | 33.7 | 33.4 |
| DN32 | 1 1/4" | 42.4 | 42.2 |
| DN40 | 1 1/2" | 48.3 | 48.3 |
| DN50 | 2" | 60.3 | 60.3 |
| DN65 | 2 1/2" | 76.1 | 73 |
| DN80 | 3" | 88.9 | 88.9 |
| DN100 | 4" | 114.3 | 114.3 |
| DN125 | 5" | 139.7 | 141.3 |
| DN150 | 6" | 168.3 | 168.3 |
| DN200 | 8" | 219.1 | 219.1 |
| DN250 | 10" | 273 | 273 |
| DN300 | 12" | 323.9 | 323.8 |
| DN350 | 14" | 355.6 | 355.6 |
| DN400 | 16" | 406.4 | 406.4 |
Elbow dimensions (ASME B16.9, long radius)
Centre-to-end dimension of butt-weld long-radius elbows: A for 90°, B for 45°.
| DN | Inch | 90° (A) | 45° (B) |
|---|---|---|---|
| DN15 | 1/2" | 38 | 16 |
| DN20 | 3/4" | 29 | 11 |
| DN25 | 1" | 38 | 22 |
| DN32 | 1 1/4" | 48 | 25 |
| DN40 | 1 1/2" | 57 | 29 |
| DN50 | 2" | 76 | 35 |
| DN65 | 2 1/2" | 95 | 44 |
| DN80 | 3" | 114 | 51 |
| DN100 | 4" | 152 | 64 |
| DN125 | 5" | 190 | 79 |
| DN150 | 6" | 229 | 95 |
| DN200 | 8" | 305 | 127 |
| DN250 | 10" | 381 | 159 |
| DN300 | 12" | 457 | 190 |
| DN350 | 14" | 533 | 222 |
| DN400 | 16" | 610 | 254 |
Flange dimensions – EN 1092-1 PN16
Flange outside diameter (D), bolt circle diameter (K), number and size of bolts, bolt hole diameter.
| DN | OD D | Bolt circle K | Bolts | Hole Ø |
|---|---|---|---|---|
| DN15 | 95 | 65 | 4 × M12 | 14 |
| DN20 | 105 | 75 | 4 × M12 | 14 |
| DN25 | 115 | 85 | 4 × M12 | 14 |
| DN32 | 140 | 100 | 4 × M16 | 18 |
| DN40 | 150 | 110 | 4 × M16 | 18 |
| DN50 | 165 | 125 | 4 × M16 | 18 |
| DN65 | 185 | 145 | 8 × M16 | 18 |
| DN80 | 200 | 160 | 8 × M16 | 18 |
| DN100 | 220 | 180 | 8 × M16 | 18 |
| DN125 | 250 | 210 | 8 × M16 | 18 |
| DN150 | 285 | 240 | 8 × M20 | 22 |
| DN200 | 340 | 295 | 12 × M20 | 22 |
| DN250 | 405 | 355 | 12 × M24 | 26 |
| DN300 | 460 | 410 | 12 × M24 | 26 |
| DN350 | 520 | 470 | 16 × M24 | 26 |
| DN400 | 580 | 525 | 16 × M27 | 30 |
Flange dimensions – ASME B16.5 Class 150
Flange outside diameter, bolt circle diameter, number of holes and hole diameter.
| Inch | OD D | Bolt circle K | Bolts | Hole Ø |
|---|---|---|---|---|
| 1/2" | 90 | 60.3 | 4 | 15.7 |
| 3/4" | 100 | 69.9 | 4 | 15.7 |
| 1" | 110 | 79.4 | 4 | 15.7 |
| 1 1/4" | 115 | 88.9 | 4 | 15.7 |
| 1 1/2" | 125 | 98.4 | 4 | 15.7 |
| 2" | 150 | 120.7 | 4 | 19.1 |
| 2 1/2" | 180 | 139.7 | 4 | 19.1 |
| 3" | 190 | 152.4 | 4 | 19.1 |
| 4" | 230 | 190.5 | 8 | 19.1 |
| 5" | 255 | 215.9 | 8 | 22.4 |
| 6" | 280 | 241.3 | 8 | 22.4 |
| 8" | 345 | 298.5 | 8 | 22.4 |
| 10" | 405 | 362 | 12 | 25.4 |
| 12" | 485 | 431.8 | 12 | 25.4 |
| 14" | 535 | 476.3 | 12 | 28.4 |
| 16" | 595 | 539.8 | 16 | 28.4 |
Values in millimetres, for information only. Confirm dimensions against the manufacturer’s catalogue and your project specification before ordering.
Request a quote for the sizes you needTechnical data
What are the dimensions of a DN50 PN16 flange?
To EN 1092-1, a DN50 PN16 flange has an outside diameter of 165 mm and a bolt circle of 125 mm, with 4 × M16 bolts in 18 mm holes.
What are the dimensions of a DN100 PN16 flange?
To EN 1092-1, a DN100 PN16 flange has an outside diameter of 220 mm and a bolt circle of 180 mm, with 8 × M16 bolts in 18 mm holes.
What are the dimensions of a DN150 PN16 flange?
To EN 1092-1, a DN150 PN16 flange has an outside diameter of 285 mm and a bolt circle of 240 mm, with 8 × M20 bolts in 22 mm holes.
What are the dimensions of a DN200 PN16 flange?
To EN 1092-1, a DN200 PN16 flange has an outside diameter of 340 mm and a bolt circle of 295 mm, with 12 × M20 bolts in 22 mm holes.
What are the dimensions of a 2 inch (DN50) elbow?
For ASME B16.9 long-radius 2" (DN50) elbows the centre-to-end dimension is 76 mm for 90° and 35 mm for 45°.
What are the dimensions of a 4 inch (DN100) elbow?
For ASME B16.9 long-radius 4" (DN100) elbows the centre-to-end dimension is 152 mm for 90° and 64 mm for 45°.
What are the dimensions of a 6 inch (DN150) elbow?
For ASME B16.9 long-radius 6" (DN150) elbows the centre-to-end dimension is 229 mm for 90° and 95 mm for 45°.
What is the outside diameter of a DN25 pipe?
A DN25 (1") pipe has an outside diameter of 33.7 mm in the European (EN) series and 33.4 mm in the American (ASME) series.
What is the outside diameter of a DN50 pipe?
A DN50 (2") pipe has an outside diameter of 60.3 mm in the European (EN) series and 60.3 mm in the American (ASME) series.
What is the outside diameter of a DN100 pipe?
A DN100 (4") pipe has an outside diameter of 114.3 mm in the European (EN) series and 114.3 mm in the American (ASME) series.