Spectacle blind (figure-8), RF 2" Class 150 — ASME B16.48
Spectacle blind (figure-8), RF 2" Class 150 to ASME B16.48: outside dia. a 102 mm, inside dia. b 61 mm, centre line c 120 mm, thickness t 6.4 mm, web width w 51 mm.
Dimensions of Spectacle blind (figure-8), RF 2" Class 150
| Symbol | Dimension | Value |
|---|---|---|
| · | Outside dia. A | 102 mm (4.016 in) |
| · | Inside dia. B | 61 mm (2.402 in) |
| · | Centre line C | 120 mm (4.724 in) |
| · | Thickness t | 6.4 mm (0.252 in) |
| · | Web width W | 51 mm (2.008 in) |
SKU TSH-BLANK-ASME-B16-48-CLASS-150-2 · Standard ASME B16.48 · verified by 2+ sources
Purchase description
SPECTACLE BLIND (FIGURE-8), RF, 2", CLASS 150, ASTM A105N, ASME B16.48
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).
Notes
- Project Materials full table; Tesco Flanges matches all rows incl. 14–24; Wermac matches 1/2–6; Dynamic Forge consistent.
- NPS 16 centre line 460 mm is less than NPS 14 (475 mm) in every source; Emirerri Steel lists 540 mm. Confirm against B16.48 before ordering.
- Web (tie bar) thickness: 6 mm minimum, or equal to t if t < 6 mm (Wermac).
- Adco Forge chart values differ for small sizes; rejected.
Same size, other ratings
Other sizes — Spectacle blind (figure-8), RF, Class 150
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.