Weld neck flange
Typical Weld Neck Flange Profile (ASME B16.5)
Designed for high pressure and high temperature service. The tapered hub transitions stress to the pipe, reducing stress concentration at the base.
Available standards and facing
- Standards: ASME B16.5, B16.47 Series A/B; DIN, PN
- Facing options: RF, RTJ, FF
- Pressure classes: 150, 300, 600, 900, 1500, 2500
Dimensional Chart — ASME B16.5 Class 150 (mm)
All dimensions are in millimeters unless otherwise specified.
| NPS (Inch) | DN (mm) | Outside Dia (D) | Thick (C) | Hub Length (L) | Bolt Circle (W) | Holes (Qty) | Hole Dia |
|---|---|---|---|---|---|---|---|
| 1/2" | 15 | 90 | 10 | 48 | 60.3 | 4 | 16 |
| 3/4" | 20 | 100 | 11.2 | 52 | 69.9 | 4 | 16 |
| 1" | 25 | 110 | 12.7 | 56 | 79.4 | 4 | 16 |
| 1-1/2" | 40 | 125 | 15.9 | 62 | 98.4 | 4 | 16 |
| 2" | 50 | 150 | 17.5 | 64 | 120.7 | 4 | 19 |
| 3" | 80 | 190 | 22.3 | 70 | 152.4 | 4 | 19 |
| 4" | 100 | 230 | 22.3 | 76 | 190.5 | 8 | 19 |
| 6" | 150 | 280 | 23.9 | 89 | 241.3 | 8 | 22 |
| 8" | 200 | 345 | 27.0 | 102 | 298.5 | 8 | 22 |
| 10" | 250 | 405 | 28.6 | 102 | 362.0 | 12 | 25 |
| 12" | 300 | 485 | 30.2 | 114 | 431.8 | 12 | 25 |
| 14" | 350 | 535 | 33.4 | 127 | 476.3 | 12 | 29 |
| 16" | 400 | 595 | 35.0 | 127 | 539.8 | 16 | 29 |
| 18" | 450 | 635 | 38.1 | 140 | 577.9 | 16 | 32 |
| 20" | 500 | 700 | 41.3 | 144 | 635.0 | 20 | 32 |
| 24" | 600 | 815 | 46.1 | 159 | 749.3 | 20 | 35 |
Materials available
- Carbon steel: e.g., ASTM A105, A350 LF2
- Stainless steel: e.g., ASTM A182 F304/F316
- Alloy steel: e.g., ASTM A182 F5/F11/F22
- Duplex: e.g., ASTM A182 F51/F53
Provide your required NPS, class, material grade, facing, and drilling — we will confirm stock or lead time.