
| DN | Mating dimensions | Flange thickness | Centre portion | ||||
| Outside diameter D | Diameter of bolt circle K | Diameter of bolt hole L | Bolting | ||||
| Number | Size | C4 | Gmax | ||||
| 10 | 125 | 85 | 18 | 4 | M16 | 24 | — |
| 15 | 130 | 90 | 18 | 4 | M16 | 26 | — |
| 25 | 160 | 115 | 22 | 4 | M20 | 34 | — |
| 40 | 195 | 145 | 26 | 4 | M24 | 38 | — |
| 50 | 210 | 160 | 26 | 8 | M24 | 42 | — |
| 65 | 255 | 200 | 30 | 8 | M27 | 51 | — |
| 80 | 275 | 220 | 30 | 8 | M27 | 55 | 43 |
| 100 | 335 | 265 | 36 | 8 | M33 | 65 | 58 |
| 125 | 380 | 310 | 36 | 12 | M33 | 75 | 78 |
| 150 | 425 | 350 | 39 | 12 | M36 | 84 | 94 |
| 200 | 525 | 440 | 42 | 16 | M39 | 103 | 140 |
| 250 | 640 | 540 | 52 | 16 | M48 | 125 | 190 |
| a For flanges type 21 the outside hub diameter approximately corresponds to the outside pipe diameter and the nominal value dimensions A, N3 and R1 and their tolerances are included for guidance only. | |||||||
EN 1092-1 PN 320 Flanges Dimension PDF:
https://www.zzflange.com/wp-content/uploads/2025/08/EN-1092-1-PN-320-Flanges-Dimension.pdf





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