BS 4504 PN16
The BS 4504 PN16 flange specification is a widely recognized standard for pipe flanges used in various industries, including oil and gas, petrochemical, water treatment, and general engineering applications. BS 4504 refers to the British Standard for circular steel flanges, and “PN16” indicates a pressure rating of 16 bar, suitable for medium-pressure systems.
DN = Nominal size, D = Outside Diameter, A = Outside Dia of Neck , B1 = Bore of Type 101 & 112 Flange, C1 = Thickness of Plate Flange,
C2 = Thickness of Weld_Neck and Boss Flange , N1 = Dia of Weld Neck , N2 = Dia of Boss ,R = corner Radius, H1 = Length of Boss Flange,
H2 = Length of Weld Neck Flange, H3 = Length of Neck :
Note: The flanges shown are only a small part of the range covered in BS 4504.
The Facings shown are type B (Raised Face). Other Facings include:
Type A..Flat: Type C..Tongue: Type D..Groove Type E..Spigot: :Type F..Recess: Type G..O-ring Recess: Type H.,0-ring Groove:
BS 4504 PN16 Flange Dimensions
| DN | D | C1 | C2 | H1 | H2 | H3 | R | A | N1 | N2 | B1 | d1 | f1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 90 | 14 | 14 | 20 | 35 | 6 | 3 | 17,2 | 28 | 30 | 18 | 40 | 2 |
| 15 | 95 | 14 | 14 | 20 | 35 | 6 | 3 | 21,3 | 32 | 35 | 22 | 45 | 2 |
| 20 | 105 | 14 | 14 | 24 | 38 | 6 | 4 | 26,9 | 39 | 45 | 27,5 | 58 | 2 |
| 25 | 115 | 16 | 16 | 24 | 38 | 6 | 4 | 33,7 | 46 | 52 | 34,5 | 68 | 2 |
| 32 | 140 | 18 | 16 | 26 | 40 | 6 | 5 | 42,4 | 56 | 60 | 43,5 | 78 | 2 |
| 40 | 150 | 18 | 16 | 26 | 42 | 7 | 5 | 48,3 | 64 | 70 | 49,5 | 88 | 3 |
| 50 | 165 | 20 | 18 | 28 | 45 | 8 | 5 | 60,3 | 74 | 84 | 61,5 | 102 | 3 |
| 65 | 185 | 20 | 18 | 32 | 45 | 10 | 6 | 76,1 | 92 | 104 | 77,5 | 122 | 3 |
| 80 | 200 | 20 | 20 | 34 | 50 | 10 | 6 | 88,9 | 110 | 118 | 90,5 | 138 | 3 |
| 100 | 220 | 22 | 20 | 40 | 52 | 12 | 6 | 114,3 | 130 | 140 | 116 | 162 | 3 |
| 125 | 250 | 22 | 22 | 44 | 55 | 12 | 6 | 139,7 | 158 | 168 | 141,5 | 188 | 3 |
| 150 | 285 | 24 | 22 | 44 | 55 | 12 | 8 | 168,3 | 184 | 195 | 170,5 | 212 | 3 |
| 200 | 340 | 26 | 24 | 44 | 62 | 16 | 8 | 219,1 | 234 | 246 | 221,5 | 268 | 3 |
| 250 | 405 | 29 | 26 | 46 | 70 | 16 | 10 | 273 | 288 | 298 | 276,5 | 320 | 3 |
| 300 | 460 | 32 | 28 | 46 | 78 | 16 | 10 | 323,9 | 342 | 350 | 327,5 | 378 | 4 |
| 350 | 520 | 35 | 30 | 57 | 82 | 16 | 10 | 355,6 | 390 | 400 | 359 | 438 | 4 |
| 400 | 580 | 38 | 32 | 63 | 85 | 16 | 10 | 406,4 | 444 | 456 | 411,0 | 490 | 4 |
| 450 | 640 | 42 | 34 | 68 | 87 | 16 | 12 | 457,0 | 490 | 502 | 462,0 | 550 | 4 |
| 500 | 715 | 46 | 34 | 73 | 90 | 16 | 12 | 508,0 | 546 | 559 | 513,5 | 610 | 4 |
| 600 | 840 | 52 | 36 | 83 | 95 | 18 | 12 | 610,0 | 650 | 658 | 616,5 | 725 | 5 |
| 700 | 910 | 60 | 36 | 83 | 100 | 18 | 12 | 711,0 | 750 | 760 | – | 795 | 5 |
| 800 | 1025 | 68 | 38 | 90 | 105 | 20 | 12 | 813,0 | 848 | 864 | – | 900 | 5 |
| 900 | 1125 | 76 | 40 | 94 | 110 | 20 | 12 | 914,0 | 948 | 968 | – | 1000 | 5 |
| 1000 | 1255 | 84 | 42 | 100 | 120 | 22 | 12 | 1016,0 | 1056 | 1072 | – | 1115 | 5 |
| 1200 | 1485 | 98 | 48 | – | 130 | 30 | 12 | 1220,0 | 1260 | – | – | 1330 | 5 |
| 1400 | 1685 | – | 52 | – | 145 | 30 | 12 | 1420,0 | 1465 | – | – | 1530 | 5 |
| 1600 | 1930 | – | 58 | – | 160 | 35 | 12 | 1620,0 | 1668 | – | – | 1750 | 5 |
| DN | D | C1 | C2 | H1 | H2 | H3 | R | A | N1 | N2 | B1 | d1 | f1 |