Flange drilling 20" Class D — AWWA C207
Flange drilling 20" Class D to AWWA C207: flange od 27.5 in, bolt circle 25 in, no. of bolts 20, bolt hole dia 1.25 in, thickness 1.125 in.
Dimensions of Flange drilling 20" Class D
| Symbol | Dimension | Value |
|---|---|---|
| · | Flange OD | 27.5 in |
| · | Bolt circle | 25 in |
| · | No. of bolts | 20 |
| · | Bolt hole dia | 1.25 in |
| · | Thickness | 1.125 in |
SKU TSH-FLANGE-AWWA-C207-CLASS-D-20 · Standard AWWA C207
Purchase description
FLANGE DRILLING, 20", CLASS D, ASTM A105N, AWWA C207
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
- Class D: 175 psi for 4-12", 150 psi for 14" and larger.
Other sizes — Flange drilling, Class D
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.