Instant per-flange weight
Dimensions and weights
Dimensional tolerances
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Select a series and pressure class to view the ANSI/ASME B16.47 bolt and stud dimensions, including number of bolts, bolt diameter, and stud length.
| Nominal Pipe Size (in) | No. Bolts | Bolt Diameter (in) | Stud Length—RF (in) |
|---|---|---|---|
| 26 | 24 | 1.250 | 8.75 |
| 28 | 28 | 1.250 | 9.00 |
| 30 | 28 | 1.250 | 9.25 |
| 32 | 28 | 1.500 | 10.50 |
| 34 | 32 | 1.500 | 10.50 |
| 36 | 32 | 1.500 | 11.25 |
| 38 | 32 | 1.500 | 11.00 |
| 40 | 36 | 1.500 | 11.25 |
| 42 | 36 | 1.500 | 11.75 |
| 44 | 40 | 1.500 | 12.00 |
| 46 | 40 | 1.500 | 12.25 |
| 48 | 44 | 1.500 | 12.50 |
| 50 | 44 | 1.750 | 13.50 |
| 52 | 44 | 1.750 | 13.75 |
| 54 | 44 | 1.750 | 14.00 |
| 56 | 48 | 1.750 | 14.50 |
| 58 | 48 | 1.750 | 14.75 |
| 60 | 52 | 1.750 | 15.00 |
We manufacture to your specifications and stock domestic AIS/Buy America and imported materials, with galvanized, epoxy, and additional coatings available. Rubber expansion joints and gaskets are also supplied on request.
ANSI/ASME B16.5 covers “standard” pipe flanges and flange fittings through NPS 24 (and includes the higher classes up to 2500, depending on size and material). ANSI/ASME B16.47 covers large-diameter blind and weld neck steel flanges from NPS 26 through NPS 60, in two dimensional series, Series A and Series B, which have different dimensions, weights, and bolting, and are not interchangeable.
Series A and Series B are two different drilling patterns for the same large-diameter flange sizes. Series B typically uses more, smaller-diameter bolts on a tighter bolt circle, while Series A uses fewer, larger bolts. The two are not interchangeable, always confirm which series your mating flange uses before ordering.
No. Bolt count, bolt diameter, and stud length are set by the standard, series, and pressure class, and stay the same whether the flange is slip-on, weld neck, or blind, and whether it’s carbon steel or stainless. Material and flange type affect the flange itself, not the bolting.
ANSI/ASME B16.47 covers large-diameter flanges from NPS 26 inch through 60 inch, in both Series A and Series B, across several pressure classes. For recommended torque, see the Series A Class 150 Torque Chart.
API International stocks the flanges you need for your project, and our machine shop can modify stock products for special requirements. Contact API International’s experienced sales team, and we will help you select the right flange for your application.
