DN 350 PN 10 flange: dimensions, bolt circle and drilling (EN 1092-1)
The DN 350 PN 10 flange to EN 1092-1 is 505 mm (19.88 in) across, with 16 holes of 22 mm (0.87 in) on a 460 mm (18.11 in) bolt circle, for M20 bolts; the pipe is 355.6 mm (14 in) outside. The holes straddle the centre lines, the first one 11.25° off, and the chord between neighbouring holes, which is the divider setting for stepping the drilling out, is 89.7 mm (3.53 in).
Dimensions
| Outside diameter | 505 mm (19.88 in) |
|---|---|
| Bolt circle (PCD) | 460 mm (18.11 in) |
| Number of holes | 16 |
| Hole diameter | 22 mm (0.87 in) |
| Bolts | M20 |
| Pipe outside diameter | 355.6 mm (14 in) |
| Angle between holes | 22.5° |
| First hole from the centre line | 11.25° |
| Chord between neighbouring holes | 89.7 mm (3.53 in) |
Draw this flange: 1:1 template and DXF
Hole coordinates
From the centre of the flange, in mm, with the first hole 11.25° off the horizontal axis and the others counter-clockwise, as the standards lay the drilling out.
| Hole | Angle | x (mm) | y (mm) |
|---|---|---|---|
| 1 | 11.25° | 225.6 | 44.9 |
| 2 | 33.75° | 191.2 | 127.8 |
| 3 | 56.25° | 127.8 | 191.2 |
| 4 | 78.75° | 44.9 | 225.6 |
| 5 | 101.25° | -44.9 | 225.6 |
| 6 | 123.75° | -127.8 | 191.2 |
| 7 | 146.25° | -191.2 | 127.8 |
| 8 | 168.75° | -225.6 | 44.9 |
| 9 | 191.25° | -225.6 | -44.9 |
| 10 | 213.75° | -191.2 | -127.8 |
| 11 | 236.25° | -127.8 | -191.2 |
| 12 | 258.75° | -44.9 | -225.6 |
| 13 | 281.25° | 44.9 | -225.6 |
| 14 | 303.75° | 127.8 | -191.2 |
| 15 | 326.25° | 191.2 | -127.8 |
| 16 | 348.75° | 225.6 | -44.9 |
Questions
- How many bolts does a %{size} %{class} flange have?
- %{holes}, of %{bolt}, through holes of %{hole} on a %{circle} bolt circle.
- What is the bolt circle of a %{size} %{class} flange?
- %{circle}. The holes are %{angle}° apart, and the first one sits %{half}° off the centre line, so that two flanges mate in any symmetric position. The chord between neighbouring holes is %{chord}.
- Can a %{size} %{class} flange be cut from plate?
- As a plate flange, for low pressure: ducts, tanks, water lines. The outline and the drilling above are what the flange calculator draws, with the 1:1 template and the DXF for plasma or laser. A pressure flange to %{standard} is forged, with a hub and a raised face, and its thickness and facing come from the standard.