ASME B16.5 — Class 150 flange (mm)
ASME B16.5 Class 150 flange (mm) — 20 sizes.
| NPS | DN | O — Outside dia (mm) | tf — Min thickness (mm) | R — Raised face dia (mm) | X — Hub dia (mm) | A — Hub at weld (mm) | Y — Weld neck (mm) | Y — Slip-on / Thr / SW (mm) | Y — Lap joint (mm) | W — Bolt circle (mm) | Holes — No. | Hole dia — mm (mm) | Bolt — in (in) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ½" | 15 | 90 | 9.6 | 34.9 | 30 | 21.3 | 46 | 14 | 16 | 60.3 | 4 | 15.9 | ½" |
| ¾" | 20 | 100 | 11.2 | 42.9 | 38 | 26.7 | 51 | 14 | 16 | 69.9 | 4 | 15.9 | ½" |
| 1" | 25 | 110 | 12.7 | 50.8 | 49 | 33.4 | 54 | 16 | 17 | 79.4 | 4 | 15.9 | ½" |
| 1¼" | 32 | 115 | 14.3 | 63.5 | 59 | 42.2 | 56 | 19 | 21 | 88.9 | 4 | 15.9 | ½" |
| 1½" | 40 | 125 | 15.9 | 73 | 65 | 48.3 | 60 | 21 | 22 | 98.4 | 4 | 15.9 | ½" |
| 2" | 50 | 150 | 17.5 | 92.1 | 78 | 60.3 | 62 | 24 | 25 | 120.7 | 4 | 19.1 | ⅝" |
| 2½" | 65 | 180 | 20.7 | 104.8 | 90 | 73 | 68 | 27 | 29 | 139.7 | 4 | 19.1 | ⅝" |
| 3" | 80 | 190 | 22.3 | 127 | 108 | 88.9 | 68 | 29 | 30 | 152.4 | 4 | 19.1 | ⅝" |
| 3½" | 90 | 215 | 22.3 | 139.7 | 122 | 101.6 | 70 | 30 | 32 | 177.8 | 8 | 19.1 | ⅝" |
| 4" | 100 | 230 | 22.3 | 157.2 | 135 | 114.3 | 75 | 32 | 33 | 190.5 | 8 | 19.1 | ⅝" |
| 5" | 125 | 255 | 22.3 | 185.7 | 164 | 141.3 | 87 | 35 | 36 | 215.9 | 8 | 22.2 | ¾" |
| 6" | 150 | 280 | 23.9 | 215.9 | 192 | 168.3 | 87 | 38 | 40 | 241.3 | 8 | 22.2 | ¾" |
| 8" | 200 | 345 | 27 | 269.9 | 246 | 219.1 | 100 | 43 | 44 | 298.5 | 8 | 22.2 | ¾" |
| 10" | 250 | 405 | 28.6 | 323.8 | 305 | 273 | 100 | 48 | 49 | 362 | 12 | 25.4 | ⅞" |
| 12" | 300 | 485 | 30.2 | 381 | 365 | 323.8 | 113 | 54 | 56 | 431.8 | 12 | 25.4 | ⅞" |
| 14" | 350 | 535 | 33.4 | 412.8 | 400 | 355.6 | 125 | 56 | 79 | 476.3 | 12 | 28.6 | 1" |
| 16" | 400 | 595 | 35 | 469.9 | 457 | 406.4 | 125 | 62 | 87 | 539.8 | 16 | 28.6 | 1" |
| 18" | 450 | 635 | 38.1 | 533.4 | 505 | 457 | 138 | 67 | 97 | 577.9 | 16 | 31.8 | 1⅛" |
| 20" | 500 | 700 | 41.3 | 584.2 | 559 | 508 | 143 | 71 | 103 | 635 | 20 | 31.8 | 1⅛" |
| 24" | 600 | 815 | 46.1 | 692.2 | 663 | 610 | 151 | 81 | 111 | 749.3 | 20 | 34.9 | 1¼" |
- Dimensions are in millimetres unless stated otherwise.
- Flange thickness tf and length through hub Y do not include the 2 mm raised face.
- Blind flanges have the same outside diameter, thickness tf and drilling as the other flange types of the same size and class.
- The bore of a weld neck or socket weld flange is machined to match the inside diameter of the pipe schedule stated in the order.
- Bolt holes are tabulated in inches in ASME B16.5; the millimetre values shown are direct conversions (bolt diameter plus ⅛").
- Stud bolt lengths do not include the height of the points. Weights are approximate catalogue values and vary with bore and manufacturer.