STANDARD · ASME-B16-47-B

ASME B16.47 Series B Flange Dimensions

ASME B16.47-2025 · ASME B16.47 Series B

ASME B16.47-2025North America, Middle Eastpressure class

ASME B16.47 Series B is the former API 605 large-diameter flange standard, covering NPS 26 to NPS 60 in classes 150 to 900. Its outside diameters are smaller than Series A for the same size and class, which makes it attractive where space or weight is constrained.

Series B is dimensionally different from Series A and from B16.5. Always quote the series explicitly, and check the mating flange before ordering — a Series B flange will not bolt to a Series A flange of the same nominal size. B16.47 covers weld-neck and blind flanges only, and Class 900 is published up to NPS 48.

Base materialASTM A105
Size notationNPS (inch)
Material options5 groups
Reference data5 topics

DIMENSIONS

Dimension tables

One row per specification. Open a size for the drawing, pressure ratings and printable A4 sheet.

Blind: A solid disc bolted over a line end or vessel opening for isolation, testing and future tie-ins. 84 specifications.

84 specifications
SizeRatingOutside Ø DThickness CRaised face D2Bolt circle KBoltingHub ALength HWeight
60″DN1500 Class 150 172695.316001662.1 52 × Ø34.9—— 1775 kg Spec sheet
60″DN1500 Class 300 1878165.116511763.7 40 × Ø60.3—— 3620 kg Spec sheet
60″DN1500 Class 400 1886188.916351752.6 32 × Ø73—— — Spec sheet
60″DN1500 Class 600 1994242.916571822.4 28 × Ø92.1—— — Spec sheet

How to read the pressure class

Series B follows the former API 605 dimensions, with a smaller outside diameter and a different bolt pattern from Series A. Ratings are ASME classes 150, 300, 400, 600 and 900, with allowable pressure from the B16.47 tables.

Edition and verification

Dimension values on this page have been checked against ASME B16.47-2025 (SI tables, cross-checked against the U.S. Customary tables). The 2025 edition prints exact metric equivalents of the inch dimensions rather than the old 5 mm-rounded values (for example 36.50 in is printed as 927 mm, not 925 mm), and defines flange thickness as excluding the raised face. Both corrections are reflected here; Series B NPS 38 and above follows Series A per the standard’s General Note (h).

Data imported 2026-11-05 08:05.