ASME B16.47 Series B Flanges are large-diameter steel flanges specifically designed for high-pressure, high-temperature piping systems. They are part of the ASME B16.47 standard, which covers butt-weld flanges and blind flanges in sizes ranging from NPS 26 to NPS 60. ASME B16.47 is a standard established by the American Society of Mechanical Engineers (ASME) specifically for defining the dimensions and pressure ratings of large-diameter steel flanges ranging from NPS 26“ to NPS 60”. This standard succeeded two separate standards: MSS SP-44 (Series A) and API 605 ( Series B).
ASME B16.47 Series B flanges, as the successor to API 605, are renowned for their unique structural design. Compared to Series A flanges, Series B flanges are typically thinner, lighter, and use more but smaller bolts. This design offers advantages in terms of installation and transportation, making them particularly suitable for projects with strict requirements for weight and cost. Contact us
ASME B16.47 Standard
Scope
This Standard covers pressure-temperature ratings, materials, dimensions, tolerances, marking, and testing for pipe flanges in sizes NPS 26 through NPS 60. Included here are flanges with rating class designations 75, 150, 300, 400, 600, and 900 with requirements given in both SI (metric) and U.S. Customary units, with diameter of bolts and flange bolt holes expressed in inch units. This Standard is limited to
(a) flanges made from cast or forged materials
(b) blind flanges made from cast, forged, or plate materials (see Tables 1 and 2)Also, included in this Standard are requirements and recommendations regarding flange bolting, flange gaskets, and flange joints.
Flange Series
This Standard provides two series of flange dimensions. Series A specifies flange dimensions for general use flanges. Series Bspecifies flange dimensions for com-pact flanges that, in most cases, have smaller bolt circle diameters than Series A flanges. These two series of flanges are, in general, not interchangeable. The user should recognize that some flanged valves, equipment bolted between flanges, and flanged equipment may be compatible with only one series of these flanges.
Material & Grades of ASME B16.47 Series A Flanges
Carbon Steel Flanges :
ASTM A105 / A105N,ASTM A350 LF2 / LF3, A694 F42 / 46 / 52 / 56 / 65 / 70
Alloy Steel Flanges :
ASTM / ASME A/SA 182 & A 387 F1, F5, F9, F11, F12, F22, F91
Stainless Steel Flanges :
ASTM A 182, A 240 F 304, 304L, 304H, 316, 316L, 316Ti, 310, 310S, 321, 321H, 317, 347, 347H, 904L
Duplex & Super Duplex Steel Flanges :
ASTM / ASME A/SA 182 F44, F45, F51, F53, F55, F60, F61
Copper Alloy Steel Flanges :
ASTM SB 61 , SB62 , SB151 , SB152 UNS No. C 70600 (Cu-Ni 90/10), C 71500 (Cu-Ni 70/30), UNS No. C 10100, 10200, 10300, 10800, 12000, 12200
Nickel Alloy Flanges :
ASTM SB564, SB160, SB472, SB162 Nickel 200 (UNS No. N02200), Nickel 201 (UNS No. N02201), Monel 400 (UNS No. N04400), Monel 500 (UNS No. N05500), Inconel 800 (UNS No. N08800), Inconel 825 (UNS No. N08825), Inconel 600 (UNS No. N06600), Inconel 625 (UNS No. N06625), Inconel 601 (UNS No. N06601), Hastelloy C 276 (UNS No.N10276), Alloy 20 (UNS No. N08020)
ASME B16.47 Series B Class 75 Dimensions
| Nominal Pipe S ize | A | C | D | E | F | G | H | I | J | R | |
| Overall Diameter | WNF Flange Thickness min | Blind Flange Thickness min | Overall Length WNF | Diameter at Weld Bevel | Hub Diameter | Face Diameter | Number of Holes | Bolt Hole Diameter | Diameter of Circle of Holes | Fillet | |
| mm | mm | mm | mm | mm | mm | mm | mm | mm | mm | ||
| 26 | 762 | 33.27 | 33.27 | 58.67 | 661.92 | 676.15 | 704.85 | 36 | 19.05 | 723.9 | 7.87 |
| 28 | 812.8 | 33.27 | 33.27 | 61.98 | 712.72 | 726.95 | 755.65 | 40 | 19.05 | 774.70 | 7.87 |
| 30 | 863.6 | 33.27 | 33.27 | 65.02 | 763.52 | 777.75 | 806.45 | 44 | 19.05 | 825.50 | 7.87 |
| 32 | 914.4 | 35.05 | 36.58 | 69.85 | 814.32 | 828.55 | 857.25 | 48 | 19.05 | 876.30 | 7.87 |
| 34 | 965.2 | 35.05 | 38.10 | 73.15 | 865.12 | 879.35 | 908.05 | 52 | 19.05 | 927.10 | 7.87 |
| 36 | 1033.5 | 36.58 | 42.42 | 85.85 | 915.92 | 934.97 | 965.20 | 40 | 22.35 | 992.12 | 9.65 |
| 38 | 1084.3 | 38.10 | 44.45 | 88.90 | 966.72 | 985.77 | 1016.0 | 40 | 22.35 | 1042.9 | 9.65 |
| 40 | 1135.1 | 38.10 | 44.45 | 91.95 | 1017.5 | 1036.57 | 1066.8 | 44 | 22.35 | 1093.7 | 9.65 |
| 42 | 1185.9 | 39.62 | 47.75 | 95.25 | 1068.3 | 1087.37 | 1117.6 | 48 | 22.35 | 1144.5 | 9.65 |
| 44 | 1251.0 | 42.93 | 49.28 | 104.65 | 1119.1 | 1139.95 | 1174.8 | 36 | 25.40 | 1203.5 | 9.65 |
| 46 | 1301.8 | 44.45 | 50.80 | 107.95 | 1169.9 | 1190.75 | 1225.6 | 40 | 25.40 | 1254.3 | 9.65 |
| 48 | 1352.6 | 45.97 | 53.85 | 111.25 | 1220.7 | 1241.55 | 1276.4 | 44 | 25.40 | 1305. 1 | 9.65 |
ASME B16.47 Series B Class 150 Dimensions
| Nominal Pipe S ize | A | C | D | E | F | G | H | I | J | R | |
| Overall Diameter | WNF Flange Thickness min | Blind Flange Thickness min | Overall Length WNF | Diameter at Weld Bevel | Hub Diameter | Face Diameter | Number of Holes | Bolt Hole Diameter | Diameter of Circle of Holes | Fillet | |
| mm | mm | mm | mm | mm | mm | mm | mm | mm | mm | ||
| 26 | 785.88 | 41.15 | 44.45 | 88.90 | 661.92 | 684.28 | 711.20 | 36 | 22.35 | 744.47 | 9.65 |
| 28 | 836.68 | 44.45 | 47.75 | 95.25 | 712.72 | 735.08 | 762.00 | 40 | 22.35 | 795.27 | 9.65 |
| 30 | 887.48 | 44.45 | 50.80 | 100.08 | 763.52 | 787.40 | 812.80 | 44 | 22.35 | 846.07 | 9.65 |
| 32 | 941.32 | 45.97 | 53.85 | 107.95 | 814.32 | 839.72 | 863.60 | 48 | 22.35 | 900.18 | 9.65 |
| 34 | 39.56 1004.8 | 49.28 | 57.15 | 110.24 | 865.12 | 892.05 | 920.75 | 40 | 25.40 | 957.33 | 9.65 |
| 36 | 1057.1 | 52.32 | 58.67 | 117.35 | 915.92 | 944.63 | 971.55 | 44 | 25.40 | 1009.7 | 9.65 |
| 38 | 1124.0 | 53.85 | 63.50 | 123.95 | 968.25 | 996.95 | 1022.4 | 40 | 28.45 | 1069.8 | 9.65 |
| 40 | 1174.8 | 55.63 | 66.55 | 128.52 | 1019.0 | 1049.3 | 1079.5 | 44 | 28.45 | 1120.6 | 9.65 |
| 42 | 1225.6 | 58.67 | 68.33 | 133.35 | 1069.8 | 1101.9 | 1130.3 | 48 | 28.45 | 1171.4 | 11.18 |
| 44 | 1276.4 | 60.45 | 71.37 | 136.65 | 1120.6 | 1152.7 | 1181.1 | 52 | 28.45 | 1222.2 | 11.18 |
| 46 | 1341.4 | 61.98 | 74.68 | 144.53 | 1171.4 | 1205.0 | 1234.9 | 40 | 31.75 | 1284.2 | 11.18 |
| 48 | 1392.2 | 65.02 | 77.72 | 149.35 | 1222.2 | 1257.3 | 1289.1 | 44 | 31.75 | 1335.0 | 11.18 |
ASME B16.47 Series B Class 300 Dimensions
| Nominal Pipe S ize | A | C | D | E | F | G | H | I | J | R | |
| Overall Diameter | WNF Flange Thickness min | Blind Flange Thickness min | Overall Length WNF | Diameter at Weld Bevel | Hub Diameter | Face Diameter | Number of Holes | Bolt Hole Diameter | Diameter of Circle of Holes | Fillet | |
| mm | mm | mm | mm | mm | mm | mm | mm | mm | mm | ||
| 26 | 866.65 | 88.90 | 88.90 | 144.53 | 665.23 | 701.55 | 736.60 | 32 | 35.05 | 803.15 | 14.22 |
| 28 | 920.75 | 88.90 | 88.90 | 149.35 | 716.03 | 755.65 | 787.40 | 36 | 35.05 | 857.25 | 14.22 |
| 30 | 990.60 | 93.73 | 93.73 | 157.99 | 768.35 | 812.80 | 844.55 | 36 | 38.10 | 920.75 | 14.22 |
| 32 | 1054.1 | 103.12 | 103.12 | 168. 15 | 819.15 | 863.60 | 901.70 | 32 | 41.15 | 977.90 | 15.75 |
| 34 | 1107.9 | 103.12 | 103.12 | 172.97 | 869.95 | 917.45 | 952.50 | 36 | 41.15 | 1031.7 | 15.75 |
| 36 | 1171.4 | 103.12 | 103.12 | 180.85 | 920.75 | 965.20 | 1009.7 | 32 | 44.45 | 1089.2 | 15.75 |
| 38 | 1222.2 | 111.25 | 111.25 | 192.02 | 971.55 | 1016.0 | 1060.5 | 36 | 44.45 | 1140.0 | 15.75 |
| 40 | 1273.0 | 115.82 | 115.82 | 198.37 | 1022.4 | 1066.8 | 1114.6 | 40 | 44.45 | 1190.8 | 15.75 |
| 42 | 1333.5 | 119.13 | 119.13 | 204.72 | 1074.7 | 1117.6 | 1168.4 | 36 | 47.75 | 1244.6 | 15.75 |
| 44 | 1384.3 | 127.00 | 127.00 | 214.38 | 1125.5 | 1173.2 | 1219.2 | 40 | 47.75 | 1295.4 | 15.75 |
| 46 | 1460.5 | 128.52 | 130.05 | 222.25 | 1176.3 | 1228.9 | 1270.0 | 36 | 50.80 | 1365.3 | 15.75 |
| 48 | 1511.3 | 128.52 | 134.87 | 223.77 | 1227.1 | 1277.9 | 1327.2 | 40 | 50.80 | 1416. 1 | 15.75 |
ASME B16.47 Series A Class 400 lb, 600 lb and 900 lb Dimensions
| Nominal Pipe S ize | A | C | D | E | F | G | H | I | J | R | |
| Overall Diameter | WNF Flange Thickness min | Blind Flange Thickness min | Overall Length WNF | Diameter at Weld Bevel | Hub Diameter | Face Diameter | Number of Holes | Bolt Hole Diameter | Diameter of Circle of Holes | Fillet | |
| mm | mm | mm | mm | mm | mm | mm | mm | mm | mm | ||
| Class 400 | |||||||||||
| 26 | 850.90 | 88.90 | 88.90 | 149.35 | 660.40 | 688.85 | 711.20 | 28 | 38.10 | 781.05 | 11.18 |
| 28 | 914.40 | 95.25 | 95.25 | 158.90 | 711.20 | 739.65 | 762.00 | 24 | 41.15 | 838.20 | 12.70 |
| 30 | 971.55 | 101.60 | 101.60 | 169.93 | 762.00 | 793.75 | 590.55 | 28 | 41.15 | 895.35 | 12.70 |
| 32 | 1035.1 | 107.95 | 107.95 | 179.32 | 812.80 | 844.55 | 873.25 | 28 | 44.45 | 952.50 | 12.70 |
| 34 | 1085.9 | 111.25 | 111.25 | 187.45 | 863.60 | 898.65 | 927.10 | 32 | 44.45 | 1003.3 | 14.22 |
| 36 | 1155.7 | 119.13 | 119.13 | 200. 15 | 914.40 | 952.50 | 980.95 | 28 | 47.75 | 1066.8 | 14.22 |
| Class 600 | |||||||||||
| 26 | 889.00 | 111.25 | 111.25 | 180.85 | 660.40 | 698.50 | 726.95 | 28 | 44.45 | 806.45 | 12.70 |
| 28 | 952.50 | 115.82 | 115.82 | 190.50 | 711.20 | 752.35 | 784.35 | 28 | 47.75 | 863.60 | 12.70 |
| 30 | 1022.4 | 125.48 | 127 | 204.72 | 762.00 | 806.45 | 841.25 | 28 | 50.80 | 927.10 | 12.70 |
| 32 | 1085.9 | 130.05 | 134.87 | 215.90 | 812.80 | 860.55 | 895.35 | 28 | 53.85 | 984.25 | 12.70 |
| 34 | 1162.1 | 141.22 | 144.27 | 233.43 | 863.60 | 914.40 | 952.50 | 24 | 60.45 | 1054.1 | 14.22 |
| 36 | 1212.9 | 146.05 | 150.88 | 242.82 | 914.40 | 968.25 | 1009.7 | 28 | 60.45 | 1104.9 | 14.22 |
| Class 900 | |||||||||||
| 26 | 1022.4 | 134.87 | 153.92 | 258.83 | 660.40 | 742.95 | 762.00 | 20 | 66.55 | 901.70 | 11.18 |
| 28 | 1104.9 | 147.57 | 166.62 | 276.35 | 711.20 | 797.05 | 819.15 | 20 | 73.15 | 971.55 | 12.70 |
| 30 | 1181.1 | 155.45 | 176.02 | 289.05 | 762.00 | 850.90 | 876.30 | 20 | 79.25 | 1035.1 | 12.70 |
| 32 | 1238.3 | 160.27 | 185.67 | 303.28 | 812.80 | 908.05 | 927.10 | 20 | 79.25 | 1092.2 | 12.70 |
| 34 | 1314.5 | 171.45 | 195.07 | 319.02 | 863.60 | 962. 15 | 990.60 | 20 | 85.85 | 1155.7 | 14.22 |
| 36 | 1346.2 | 172.97 | 201.68 | 325.37 | 914.40 | 1016.0 | 1028.7 | 24 | 79.25 | 1200.2 | 14.22 |
Differences between Series B and Series A Flanges
Thickness and Weight: Series B flanges are thinner and lighter.
Number and Size of Bolts: Series B flanges utilize a larger number of smaller-diameter bolts, while Series A flanges utilize a smaller number of larger-diameter bolts.
Strength and Load-Carrying Capacity: Series A flanges are thicker and heavier, capable of withstanding higher external loads, making them more popular in more demanding, high-pressure environments. Series B flanges are more suitable for general pipe connections.
Flange Types: ASME B16.47 Series B primarily includes weld neck flanges and blind flanges and is the only series in the standard to offer a Class 75 pressure rating.
Applications of ASME B16.47 Series B Flanges
Oil & Gas pipelines
Petrochemical plants
Water treatment and desalination projects
Power generation systems
Structural and general industrial piping
Advantages of Using Series B Flanges
Cost-effective for large diameter pipelines
Easy availability in multiple materials and sizes
Reliable sealing with fewer bolts
Reduced overall piping system weight
Why Choose ZIZI for ASME B16.47 Series B Flanges?
At ZIZI Engineering, we manufacture and supply a wide range of ASME B16.47 Series B weld neck and blind flanges. Our products are produced according to ASME, ASTM, and ANSI standards, ensuring durability and performance.
* Quality Assurance: 100% inspection before delivery
* Wide Material Range: Carbon steel, stainless steel, alloy steel, duplex
* Global Supply: Fast delivery with strong export packaging
* Customization: Available upon client request