Weld Neck Flange RF 16" Class 900 — ASME B16.5
Weld Neck Flange RF 16" Class 900 to ASME B16.5: outside diameter 705 mm, flange thickness, min 88.9 mm, raised face diameter 469.9 mm, raised face height 6.4 mm, bolt circle (pcd) 616 mm; approx. weight 222.3 kg.
Dimensions of Weld Neck Flange RF 16" Class 900
| Symbol | Dimension | Value |
|---|---|---|
| O | Outside diameter | 705 mm (27.756 in) |
| tf | Flange thickness, min | 88.9 mm (3.500 in) |
| R | Raised face diameter | 469.9 mm (18.500 in) |
| f | Raised face height | 6.4 mm (0.252 in) |
| W | Bolt circle (PCD) | 616 mm (24.252 in) |
| n | Number of bolt holes | 20 |
| h | Bolt hole diameter | 44.5 mm (1.752 in) |
| d | Stud bolt size | 1-5/8" |
| Y | Length through hub | 216 mm (8.504 in) |
| A | Hub diameter at weld (pipe OD) | 406.4 mm (16.000 in) |
| B | Bore (Sch 40) | 381 mm (15.000 in) |
| m | Approximate weight | 222.3 kg (490.09 lb) |
SKU TSH-FLANGE-WN-B165-900-16 · Standard ASME B16.5 · weight: Calculated from nominal dimensions, carbon steel (ρ 7850 kg/m³)
Purchase description
FLANGE, WELD NECK, RAISED FACE, 16" (DN 400), CLASS 900, BORE SCH 40, ASTM A105N, ASME B16.5
Available materials: ASTM A105N, ASTM A350 LF2 Cl 1, ASTM A182 F304/304L, ASTM A182 F316/316L, ASTM A182 F11 Cl 2, ASTM A182 F22 Cl 3, ASTM A182 F51 (Duplex), ASTM A182 F53 (Super Duplex), ASTM A694 F52 / F60, IS 2062 E250 (plate).
Bolting and gasket
20 stud bolts 1-5/8" UNC × 310 mm (12.25") with 40 heavy hex nuts — ASTM A193 B7 studs + A194 2H heavy hex nuts. Gasket: Spiral wound 16" Class 900, ASME B16.20, SS316 + graphite, CS outer ring, SS inner ring.
Additional data
| Facing | Raised face 6.4 mm, 3.2–6.3 µm Ra serrated |
Same size, other ratings
Other sizes — Weld Neck, Class 900
Frequently asked questions
What are the main types of pipe flanges?
Weld neck (WN), slip-on (SO), blind (BL), socket weld (SW), threaded (THD), lap joint (LJ) and plate flanges. Special types include orifice, long weld neck, reducing flanges and spectacle blinds.
When should I use a weld neck flange instead of a slip-on?
Use weld neck flanges for high pressure, high or cycling temperature, and lines with vibration or fatigue loading. The tapered hub and full-penetration butt weld spread stress smoothly. Slip-on flanges are cheaper and easier to align, but their fatigue life is roughly one third of a WN.
What does Class 150, 300 or 600 mean on a flange?
The ASME class is a pressure-rating designation, not a pressure in psi. The allowable pressure depends on the material group and temperature. A Class 150 A105 flange is rated 19.6 bar at 38 °C but 13.8 bar at 200 °C.
Is a 150# flange rated for 150 psi?
No. A Class 150 carbon-steel flange is rated about 285 psi (19.6 bar) at ambient temperature, and about 170 psi (11.7 bar) at 260 °C. The "150" is a class number.