General
Unless otherwise specified flanged fittings will be supplied in
accordance with ANSI/AWWA C110/A21.10. They may have the following
ratings:
Table 1.1
| Size | Working Pressure | Material | Flange Drilling |
| 3" - 12" | 250 psi | CI & DI | Class 125* |
| 14" - 48" | 150 psi | CI | Class 125* |
| 14" - 48" | 250 psi | CI | Class 125* |
| 14" - 48" | 250 psi | DI | Class 125* |
*Flange drilling is in accordance with ANSI B16.1 (Class 125). Fittings
may be specified with flanges modified to extra-heavy 250 lb (Class
250) drilling. Laying length and wall thickness of these fittings
conform with ANSI/AWWA C110/A21.10 with both drilling patterns in
accordance with ANSI B16.1. However, Class 250 flanged ends are larger,
thicker, possess different bolt circles and may have more bolt holes.
Class 125 flanged fittings cannot be joined to Class 250 fittings even
though both are rated at 250 psi water working pressure.
Note: Class 250 flanges have raised faces. If Class 250 flanges have raised faces, they should not be mated with flat faced Class 250 flanges.
