ASME B16.47 Series B Flange Dimensions
ASME B16.47 Series B (formerly API 605) covers large-diameter weld neck and blind flanges from NPS 26" to 60". This chart gives the dimensions in millimetres for Class 150 and 300.
Series B flanges are more compact and lighter, with more, smaller bolts; they are common on refinery and equipment connections where space and weight matter. Series A and Series B flanges of the same size and class are not interchangeable. Teshi Group manufactures both series as an OEM.
Key to dimensions
- O
- Outside diameter of flange
- tf
- Minimum thickness of weld neck and of blind flange, excluding the raised face
- X
- Hub diameter at base
- A
- Hub diameter at the welding end
- Y
- Length through hub, excluding the raised face
- R
- Diameter of raised face
- W
- Bolt circle diameter
- Holes
- Number and diameter of bolt holes
ASME B16.47 Series B Flange dimensions — tables
Series B Class 150 (mm)
| NPSin | DN | OOutside dia | tfWeld neck | tfBlind | XHub dia | AHub at weld | YLength thru hub | RRaised face dia | WBolt circle | HolesNo. | Hole diamm | Boltin |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 26" | 650 | 785 | 39.8 | 43.0 | 684 | 661.9 | 87 | 711 | 744.5 | 36 | 22.2 | ¾" |
| 28" | 700 | 835 | 43.0 | 46.2 | 735 | 712.7 | 94 | 762 | 795.3 | 40 | 22.2 | ¾" |
| 30" | 750 | 885 | 43.0 | 49.3 | 787 | 763.5 | 98 | 813 | 846.1 | 44 | 22.2 | ¾" |
| 32" | 800 | 940 | 44.6 | 52.5 | 840 | 814.3 | 106 | 864 | 900.1 | 48 | 22.2 | ¾" |
| 34" | 850 | 1005 | 47.7 | 55.7 | 892 | 865.1 | 109 | 921 | 957.3 | 40 | 25.4 | ⅞" |
| 36" | 900 | 1055 | 50.9 | 57.3 | 945 | 915.9 | 116 | 972 | 1009.6 | 44 | 25.4 | ⅞" |
| 38" | 950 | 1125 | 52.5 | 62.0 | 997 | 968.2 | 122 | 1022 | 1070.0 | 40 | 28.6 | 1" |
| 40" | 1000 | 1175 | 54.1 | 65.2 | 1049 | 1019.0 | 127 | 1080 | 1120.8 | 44 | 28.6 | 1" |
| 42" | 1050 | 1225 | 57.3 | 66.8 | 1102 | 1069.8 | 132 | 1130 | 1171.6 | 48 | 28.6 | 1" |
| 44" | 1100 | 1275 | 58.9 | 70.0 | 1153 | 1120.6 | 135 | 1181 | 1222.4 | 52 | 28.6 | 1" |
| 46" | 1150 | 1340 | 60.4 | 73.1 | 1205 | 1171.4 | 143 | 1235 | 1284.3 | 40 | 31.8 | 1⅛" |
| 48" | 1200 | 1390 | 63.6 | 76.3 | 1257 | 1222.2 | 148 | 1289 | 1335.1 | 44 | 31.8 | 1⅛" |
| 50" | 1250 | 1445 | 66.8 | 79.5 | 1308 | 1273.0 | 152 | 1340 | 1385.9 | 48 | 31.8 | 1⅛" |
| 52" | 1300 | 1495 | 68.4 | 82.7 | 1360 | 1323.8 | 156 | 1391 | 1436.7 | 52 | 31.8 | 1⅛" |
| 54" | 1350 | 1550 | 70.0 | 85.8 | 1413 | 1374.6 | 160 | 1441 | 1492.2 | 56 | 31.8 | 1⅛" |
| 56" | 1400 | 1600 | 71.6 | 89.0 | 1465 | 1425.4 | 165 | 1492 | 1543.0 | 60 | 31.8 | 1⅛" |
| 58" | 1450 | 1675 | 73.1 | 91.9 | 1516 | 1476.2 | 173 | 1543 | 1611.3 | 48 | 34.9 | 1¼" |
| 60" | 1500 | 1725 | 74.7 | 95.4 | 1570 | 1527.0 | 178 | 1600 | 1662.1 | 52 | 34.9 | 1¼" |
Series B Class 300 (mm)
| NPSin | DN | OOutside dia | tfWeld neck | tfBlind | XHub dia | AHub at weld | YLength thru hub | RRaised face dia | WBolt circle | HolesNo. | Hole diamm | Boltin |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 26" | 650 | 865 | 87.4 | 87.4 | 702 | 665.2 | 143 | 737 | 803.3 | 32 | 34.9 | 1¼" |
| 28" | 700 | 920 | 87.4 | 87.4 | 756 | 716.0 | 148 | 787 | 857.2 | 36 | 34.9 | 1¼" |
| 30" | 750 | 990 | 92.1 | 92.1 | 813 | 768.4 | 156 | 845 | 920.8 | 36 | 38.1 | 1⅜" |
| 32" | 800 | 1055 | 101.6 | 101.6 | 864 | 819.2 | 167 | 902 | 977.9 | 32 | 41.3 | 1½" |
| 34" | 850 | 1110 | 101.6 | 101.6 | 918 | 870.0 | 171 | 953 | 1031.9 | 36 | 41.3 | 1½" |
| 36" | 900 | 1170 | 101.6 | 101.6 | 965 | 920.8 | 179 | 1010 | 1089.0 | 32 | 44.5 | 1⅝" |
| 38" | 950 | 1220 | 109.6 | 109.6 | 1016 | 971.6 | 190 | 1060 | 1139.8 | 36 | 44.5 | 1⅝" |
| 40" | 1000 | 1275 | 114.3 | 114.3 | 1067 | 1022.4 | 197 | 1114 | 1190.6 | 40 | 44.5 | 1⅝" |
| 42" | 1050 | 1335 | 117.5 | 117.5 | 1118 | 1074.7 | 203 | 1168 | 1244.6 | 36 | 47.6 | 1¾" |
| 44" | 1100 | 1385 | 125.5 | 125.5 | 1173 | 1125.5 | 213 | 1219 | 1295.4 | 40 | 47.6 | 1¾" |
| 46" | 1150 | 1460 | 127.0 | 128.6 | 1229 | 1176.3 | 221 | 1270 | 1365.2 | 36 | 50.8 | 1⅞" |
| 48" | 1200 | 1510 | 127.0 | 133.4 | 1278 | 1227.1 | 222 | 1327 | 1416.0 | 40 | 50.8 | 1⅞" |
| 50" | 1250 | 1560 | 136.6 | 138.2 | 1330 | 1277.9 | 233 | 1378 | 1466.8 | 44 | 50.8 | 1⅞" |
| 52" | 1300 | 1615 | 141.3 | 142.6 | 1383 | 1328.7 | 241 | 1429 | 1517.6 | 48 | 50.8 | 1⅞" |
| 54" | 1350 | 1675 | 135.0 | 147.7 | 1435 | 1379.5 | 238 | 1480 | 1578.0 | 48 | 50.8 | 1⅞" |
| 56" | 1400 | 1765 | 152.4 | 155.4 | 1494 | 1430.3 | 267 | 1537 | 1651.0 | 36 | 60.3 | 2¼" |
| 58" | 1450 | 1825 | 152.4 | 160.4 | 1548 | 1481.1 | 273 | 1594 | 1712.9 | 40 | 60.3 | 2¼" |
| 60" | 1500 | 1880 | 149.3 | 165.1 | 1599 | 1531.9 | 270 | 1651 | 1763.7 | 40 | 60.3 | 2¼" |
Notes
- Dimensions are in millimetres unless stated otherwise.
- Thickness and hub length exclude the raised face: 2 mm for Class 150 and 300.
- Bolt holes are tabulated in inches in the standard; millimetre values are direct conversions.
- Some dimensions do not increase uniformly with size (for example Class 300 thickness at NPS 54" and 60"). This follows the standard.
Reference information compiled from the published standard for convenience. It does not replace the current edition of the governing standard, which takes precedence. Verify critical dimensions and properties before design, purchase or fabrication. Teshi Engineers & Sales Promoters (P) Ltd accepts no liability for errors or omissions.
Equivalent and related standards to ASME B16.47 Series B Flange Dimensions
All equivalents| Region | Standard | Relationship |
|---|---|---|
| USA | API 605 (withdrawn) | Source standard of Series B dimensions |
| China | HG/T 20623 Series B | Large-diameter Class flanges — ASME B16.47 dimensions |
| China | GB/T 9124.2 (large diameter, Series B) | National standard large-diameter Class flanges |
| China | SH/T 3406 (NPS 26 and above) | Petrochemical large-diameter flanges |
| Europe | EN 1759-1 (NPS 26 and above) | Class-rated flanges based on ASME dimensions |
Teshi Group manufactures flanges and fittings to all of these standards on request, including Chinese GB / HG / SH and European EN dimensions for export projects. Always confirm bolting, facing and thickness when substituting one standard for another.
Dimension finder
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ASME B16.47 Series B Flange Dimensions — size by size
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FAQ
ASME B16.47 Series B flange dimensions: common questions
What is the difference between ASME B16.47 Series A and Series B?
Series A (formerly MSS SP-44) is heavier and thicker with fewer, larger bolts. Series B (formerly API 605) is more compact with more, smaller bolts. They do not mate with each other.
Which flange types does ASME B16.47 cover?
Weld neck and blind flanges only, from NPS 26" to 60". Slip-on and other types in these sizes are made to other standards or to drawing.
Related products, data sheets and standards
Large Diameter Flange (ASME B16.47)
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Large-diameter Series A (MSS SP-44) flanges, Class 150, 300 and 600, NPS 26–60.
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