ASME B16.47 Series A Flanges
Series A is the heavier of the two large-flange series, which the standard describes as the one for general use. It has a larger outside diameter, a thicker flange and fewer, larger bolts than Series B at the same size and class. Class 900 is published through NPS 48 only.
- Standard
- ASME B16.47
- Series
- Series A
- Derived from
- MSS SP-44
- Sizes
- NPS 26 through NPS 60, Class 900 through NPS 48
- Classes
- 150, 300, 400, 600 and 900
Dimension tables
Not interchangeable with Series B. The two series differ in outside diameter, bolt circle and bolt count in Classes 75, 150 and 300, and in NPS 36 and smaller in the higher classes. At NPS 38 and larger in Classes 400, 600 and 900 the two series have the same dimensions. Never mix them in a joint without checking.
Common questions
What is ASME B16.47 Series A?
Series A is the heavier of the two large-flange series, which the standard describes as the one for general use. It has a larger outside diameter, a thicker flange and fewer, larger bolts than Series B at the same size and class. Class 900 is published through NPS 48 only.
What classes does Series A come in?
Class 150, Class 300, Class 400, Class 600 and Class 900, in sizes nps 26 through nps 60, class 900 through nps 48. Series B carries Class 75, Class 150, Class 300, Class 400, Class 600 and Class 900 instead, which is one reason the two are easy to confuse on a requisition.