Standard flanges are plain-faced without projection or raised faced
and are furnished smooth or with shallow serrations (re: Table A and
Table B).
Either ductile-iron or gray-iron flanges may be used unless otherwise specified by the owner. (re: ANSI/AWWA C115/A21.15).
Flanges shall have a taper pipe thread (NPT) in accordance with ANSI
BI.20.1 adapted to ductile iron pipe outside diameters. (re: Table C.)
Pressure Ratings
Ductile Iron and Gray Iron Flanges,3"-54", shall be rated at 250 psi
working pressure. Bolt circle and bolt holes can be joined with class
125 ANSI B16.1 or class 150 ANSI B16.5 flanges. However these flanges
cannot be joined with class 250 ANSI B16.1 flanges.
General Requirements
All flanges shall be capable of withstanding a hydrostatic test of
1.5 times the rated water working pressure, without fracture.
Axial beam loads shall be sufficient for their intended use. For all
flanges, load values shall be no less than those of cast iron flanges.
Flanges shall conform to the dimensions shown in tables A and B,
unless otherwise agreed upon at the time of purchase. Flanges of other
variations shall be allowed provided they meet the performance
requirements of this standard and other applicable standard.
