ASME B16.5 · B16.47 · JIS B2220 · EN 1092-1
Blind Flange Manufacturer — ASME B16.5, B16.47, JIS B2220, EN 1092-1
Blind flanges close a pipe, valve or vessel opening and are designed to carry the full pressure load across an unsupported disc — the thickest and most highly stressed flange in any line class.
Standard
ASME B16.5 / B16.47 / JIS B2220 / EN 1092-1
Size range
1/2″–60″ (ASME) · 10A–600A (JIS) · DN10–DN600 (EN)
Pressure class
Class 150–2500 · 5K–30K · PN6–PN40
Materials
A105, A350 LF2, 304/316L, F11/F22, 2205
Faces
RF, FF, RTJ
Options
Tapped centre port, custom bolt pattern
A blind flange (BL) is a solid disc with a bolt circle that mates to a standard flange. Because there is no bore, the plate must resist the full internal pressure in bending, so B16.5 specifies a thicker section than for a weld neck or slip-on flange of the same size and class. Blind flanges are used for line ends, vessel manways, test points, future tie-ins and temporary isolation during commissioning and turnaround.
We machine blind flanges to B16.5 in A105, A350 LF2, 304/304L, 316/316L, F11/F22 and duplex, with RF, FF or RTJ faces. Each disc is checked for thickness, flatness, bolt-hole spacing and face finish, and can be supplied drilled to a non-standard bolt pattern or with a tapped centre port for pressure testing. For large-diameter closures we also produce B16.47 Series A and B blinds up to 60″.
Dimensions by standard — ASME, JIS and EN
Each table is the published dimension record for one standard and rating. ASME values are shown in millimetres with the inch equivalent; JIS B2220 and EN 1092-1 values are metric as published. Flange thickness excludes the raised-face height (1.5 mm for ASME B16.5 Classes 150/300, 6.4 mm for Classes 400–2500, 1.5 mm for B16.47 Classes 75/150/300 and 6.4 mm for Classes 400–900, 2 mm for JIS/EN). A size link opens the full specification page for that size and rating.
ASME B16.5
ASME B16.5-2025 · North America, Middle East, South-East Asia
blind flange · Class 150
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| 1/2″ | 15 | 88.9 mm (3.5″) | 11.2 mm (0.44″) | 35.1 mm (1.38″) | 60.5 mm (2.38″) | 4 × Ø15.9 mm (0.63″) | 0.5 kg | Details → |
| 3/4″ | 20 | 98.6 mm (3.88″) | 12.7 mm (0.5″) | 42.9 mm (1.69″) | 69.9 mm (2.75″) | 4 × Ø15.9 mm (0.63″) | 0.9 kg | Details → |
| 1″ | 25 | 108 mm (4.25″) | 14.2 mm (0.56″) | 50.8 mm (2″) | 79.2 mm (3.12″) | 4 × Ø15.9 mm (0.63″) | 0.9 kg | Details → |
| 1¼″ | 32 | 117.3 mm (4.62″) | 15.7 mm (0.62″) | 63.5 mm (2.5″) | 88.9 mm (3.5″) | 4 × Ø15.9 mm (0.63″) | 1.4 kg | Details → |
| 1½″ | 40 | 127 mm (5″) | 17.5 mm (0.69″) | 73.2 mm (2.88″) | 98.6 mm (3.88″) | 4 × Ø15.9 mm (0.63″) | 1.8 kg | Details → |
| 2″ | 50 | 152.4 mm (6″) | 19.1 mm (0.75″) | 91.9 mm (3.62″) | 120.7 mm (4.75″) | 4 × Ø19.1 mm (0.75″) | 2.3 kg | Details → |
| 2½″ | 65 | 177.8 mm (7″) | 22.4 mm (0.88″) | 104.6 mm (4.12″) | 139.7 mm (5.5″) | 4 × Ø19.1 mm (0.75″) | 3.2 kg | Details → |
| 3″ | 80 | 190.5 mm (7.5″) | 23.9 mm (0.94″) | 127 mm (5″) | 152.4 mm (6″) | 4 × Ø19.1 mm (0.75″) | 4.1 kg | Details → |
| 3½″ | 90 | 215.9 mm (8.5″) | 23.9 mm (0.94″) | 139.7 mm (5.5″) | 177.8 mm (7″) | 8 × Ø19.1 mm (0.75″) | 5.9 kg | Details → |
| 4″ | 100 | 228.6 mm (9″) | 23.9 mm (0.94″) | 157.2 mm (6.19″) | 190.5 mm (7.5″) | 8 × Ø19.1 mm (0.75″) | 7.7 kg | Details → |
| 5″ | 125 | 254 mm (10″) | 23.9 mm (0.94″) | 185.7 mm (7.31″) | 215.9 mm (8.5″) | 8 × Ø22.2 mm (0.87″) | 9.1 kg | Details → |
| 6″ | 150 | 279.4 mm (11″) | 25.4 mm (1″) | 215.9 mm (8.5″) | 241.3 mm (9.5″) | 8 × Ø22.2 mm (0.87″) | 11.8 kg | Details → |
| 8″ | 200 | 342.9 mm (13.5″) | 28.4 mm (1.12″) | 269.7 mm (10.62″) | 298.5 mm (11.75″) | 8 × Ø22.2 mm (0.87″) | 20.4 kg | Details → |
| 10″ | 250 | 406.4 mm (16″) | 30.2 mm (1.19″) | 323.9 mm (12.75″) | 362 mm (14.25″) | 12 × Ø25.4 mm (1″) | 31.8 kg | Details → |
| 12″ | 300 | 482.6 mm (19″) | 31.8 mm (1.25″) | 381 mm (15″) | 431.8 mm (17″) | 12 × Ø25.4 mm (1″) | 49.9 kg | Details → |
| 14″ | 350 | 533.4 mm (21″) | 35.1 mm (1.38″) | 412.8 mm (16.25″) | 476.3 mm (18.75″) | 12 × Ø28.6 mm (1.13″) | 63.5 kg | Details → |
| 16″ | 400 | 596.9 mm (23.5″) | 36.6 mm (1.44″) | 469.9 mm (18.5″) | 539.8 mm (21.25″) | 16 × Ø28.6 mm (1.13″) | 81.6 kg | Details → |
| 18″ | 450 | 635 mm (25″) | 39.6 mm (1.56″) | 533.4 mm (21″) | 577.9 mm (22.75″) | 16 × Ø31.8 mm (1.25″) | 99.8 kg | Details → |
| 20″ | 500 | 698.5 mm (27.5″) | 42.9 mm (1.69″) | 584.2 mm (23″) | 635 mm (25″) | 20 × Ø31.8 mm (1.25″) | 129 kg | Details → |
| 22″ | 550 | 749.3 mm (29.5″) | 46 mm (1.81″) | 641.4 mm (25.25″) | 692.2 mm (27.25″) | 20 × Ø28.6 mm (1.13″) | — | Details → |
| 24″ | 600 | 812.8 mm (32″) | 47.8 mm (1.88″) | 692.2 mm (27.25″) | 749.3 mm (29.5″) | 20 × Ø34.9 mm (1.37″) | 195 kg | Details → |
blind flange · Class 300
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| 1/2″ | 15 | 95.3 mm (3.75″) | 14.2 mm (0.56″) | 35.1 mm (1.38″) | 66.5 mm (2.62″) | 4 × Ø15.9 mm (0.63″) | 0.9 kg | Details → |
| 3/4″ | 20 | 117.3 mm (4.62″) | 15.7 mm (0.62″) | 42.9 mm (1.69″) | 82.6 mm (3.25″) | 4 × Ø19.1 mm (0.75″) | 1.4 kg | Details → |
| 1″ | 25 | 124 mm (4.88″) | 17.5 mm (0.69″) | 50.8 mm (2″) | 88.9 mm (3.5″) | 4 × Ø19.1 mm (0.75″) | 1.4 kg | Details → |
| 1¼″ | 32 | 133.4 mm (5.25″) | 19.1 mm (0.75″) | 63.5 mm (2.5″) | 98.6 mm (3.88″) | 4 × Ø19.1 mm (0.75″) | 1.8 kg | Details → |
| 1½″ | 40 | 155.4 mm (6.12″) | 20.6 mm (0.81″) | 73.2 mm (2.88″) | 114.3 mm (4.5″) | 4 × Ø22.2 mm (0.87″) | 2.7 kg | Details → |
| 2″ | 50 | 165.1 mm (6.5″) | 22.4 mm (0.88″) | 91.9 mm (3.62″) | 127 mm (5″) | 8 × Ø19.1 mm (0.75″) | 3.6 kg | Details → |
| 2½″ | 65 | 190.5 mm (7.5″) | 25.4 mm (1″) | 104.6 mm (4.12″) | 149.4 mm (5.88″) | 8 × Ø22.2 mm (0.87″) | 5.4 kg | Details → |
| 3″ | 80 | 209.6 mm (8.25″) | 28.4 mm (1.12″) | 127 mm (5″) | 168.1 mm (6.62″) | 8 × Ø22.2 mm (0.87″) | 7.3 kg | Details → |
| 3½″ | 90 | 228.6 mm (9″) | 30.2 mm (1.19″) | 139.7 mm (5.5″) | 184.2 mm (7.25″) | 8 × Ø22.2 mm (0.87″) | 9.5 kg | Details → |
| 4″ | 100 | 254 mm (10″) | 31.8 mm (1.25″) | 157.2 mm (6.19″) | 200.2 mm (7.88″) | 8 × Ø22.2 mm (0.87″) | 12.2 kg | Details → |
| 5″ | 125 | 279.4 mm (11″) | 35.1 mm (1.38″) | 185.7 mm (7.31″) | 235 mm (9.25″) | 8 × Ø22.2 mm (0.87″) | 15.9 kg | Details → |
| 6″ | 150 | 317.5 mm (12.5″) | 36.6 mm (1.44″) | 215.9 mm (8.5″) | 269.7 mm (10.62″) | 12 × Ø22.2 mm (0.87″) | 22.7 kg | Details → |
| 8″ | 200 | 381 mm (15″) | 41.1 mm (1.62″) | 269.7 mm (10.62″) | 330.2 mm (13″) | 12 × Ø25.4 mm (1″) | 36.7 kg | Details → |
| 10″ | 250 | 444.5 mm (17.5″) | 47.8 mm (1.88″) | 323.9 mm (12.75″) | 387.4 mm (15.25″) | 16 × Ø28.6 mm (1.13″) | 56.2 kg | Details → |
| 12″ | 300 | 520.7 mm (20.5″) | 50.8 mm (2″) | 381 mm (15″) | 450.9 mm (17.75″) | 16 × Ø31.8 mm (1.25″) | 83.9 kg | Details → |
| 14″ | 350 | 584.2 mm (23″) | 53.8 mm (2.12″) | 412.8 mm (16.25″) | 514.4 mm (20.25″) | 20 × Ø31.8 mm (1.25″) | 113 kg | Details → |
| 16″ | 400 | 647.7 mm (25.5″) | 57.2 mm (2.25″) | 469.9 mm (18.5″) | 571.5 mm (22.5″) | 20 × Ø34.9 mm (1.37″) | 134 kg | Details → |
| 18″ | 450 | 711.2 mm (28″) | 60.5 mm (2.38″) | 533.4 mm (21″) | 628.7 mm (24.75″) | 24 × Ø34.9 mm (1.37″) | 179 kg | Details → |
| 20″ | 500 | 774.7 mm (30.5″) | 63.5 mm (2.5″) | 584.2 mm (23″) | 685.8 mm (27″) | 24 × Ø34.9 mm (1.37″) | 229 kg | Details → |
| 22″ | 550 | 838.2 mm (33″) | 66.5 mm (2.62″) | 641.4 mm (25.25″) | 743 mm (29.25″) | 24 × Ø41.3 mm (1.63″) | — | Details → |
| 24″ | 600 | 914.4 mm (36″) | 69.9 mm (2.75″) | 692.2 mm (27.25″) | 812.8 mm (32″) | 24 × Ø41.3 mm (1.63″) | 358 kg | Details → |
ASME B16.47 Series A
ASME B16.47-2025, Series A · North America, Middle East
blind flange · Class 150
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| 26″ | 650 | 870 mm (34.25″) | 66.8 mm (2.63″) | 749 mm (29.49″) | 806.4 mm (31.75″) | 24 × Ø34.9 mm (1.37″) | 318 kg | Details → |
| 28″ | 700 | 927 mm (36.5″) | 69.8 mm (2.75″) | 800 mm (31.5″) | 863.6 mm (34″) | 28 × Ø34.9 mm (1.37″) | 378 kg | Details → |
| 30″ | 750 | 984 mm (38.74″) | 73.2 mm (2.88″) | 857 mm (33.74″) | 914.4 mm (36″) | 28 × Ø34.9 mm (1.37″) | 445 kg | Details → |
| 32″ | 800 | 1060 mm (41.73″) | 79.5 mm (3.13″) | 914 mm (35.98″) | 977.9 mm (38.5″) | 28 × Ø41.3 mm (1.63″) | 562 kg | Details → |
| 34″ | 850 | 1111 mm (43.74″) | 81 mm (3.19″) | 965 mm (37.99″) | 1028.7 mm (40.5″) | 32 × Ø41.3 mm (1.63″) | 628 kg | Details → |
| 36″ | 900 | 1168 mm (45.98″) | 88.9 mm (3.5″) | 1022 mm (40.24″) | 1085.8 mm (42.75″) | 32 × Ø41.3 mm (1.63″) | 760 kg | Details → |
| 38″ | 950 | 1238 mm (48.74″) | 85.9 mm (3.38″) | 1073 mm (42.24″) | 1149.4 mm (45.25″) | 32 × Ø41.3 mm (1.63″) | 825 kg | Details → |
| 40″ | 1000 | 1289 mm (50.75″) | 88.9 mm (3.5″) | 1124 mm (44.25″) | 1200.2 mm (47.25″) | 36 × Ø41.3 mm (1.63″) | 925 kg | Details → |
| 42″ | 1050 | 1346 mm (52.99″) | 95.2 mm (3.75″) | 1194 mm (47.01″) | 1257.3 mm (49.5″) | 36 × Ø41.3 mm (1.63″) | 1080 kg | Details → |
| 44″ | 1100 | 1403 mm (55.24″) | 100.1 mm (3.94″) | 1245 mm (49.02″) | 1314.4 mm (51.75″) | 40 × Ø41.3 mm (1.63″) | 1232 kg | Details → |
| 46″ | 1150 | 1454 mm (57.24″) | 101.6 mm (4″) | 1295 mm (50.98″) | 1365.2 mm (53.75″) | 40 × Ø41.3 mm (1.63″) | 1343 kg | Details → |
| 48″ | 1200 | 1511 mm (59.49″) | 106.4 mm (4.19″) | 1359 mm (53.5″) | 1422.4 mm (56″) | 44 × Ø41.3 mm (1.63″) | 1520 kg | Details → |
| 50″ | 1250 | 1568 mm (61.73″) | 109.7 mm (4.32″) | 1410 mm (55.51″) | 1479.6 mm (58.25″) | 44 × Ø47.6 mm (1.87″) | 1686 kg | Details → |
| 52″ | 1300 | 1626 mm (64.02″) | 114.3 mm (4.5″) | 1461 mm (57.52″) | 1536.7 mm (60.5″) | 44 × Ø47.6 mm (1.87″) | 1885 kg | Details → |
| 54″ | 1350 | 1683 mm (66.26″) | 119.1 mm (4.69″) | 1511 mm (59.49″) | 1593.8 mm (62.75″) | 44 × Ø47.6 mm (1.87″) | 2103 kg | Details → |
| 56″ | 1400 | 1746 mm (68.74″) | 122.4 mm (4.82″) | 1575 mm (62.01″) | 1651 mm (65″) | 48 × Ø47.6 mm (1.87″) | 2327 kg | Details → |
| 58″ | 1450 | 1803 mm (70.98″) | 127 mm (5″) | 1626 mm (64.02″) | 1708.2 mm (67.25″) | 48 × Ø47.6 mm (1.87″) | 2574 kg | Details → |
| 60″ | 1500 | 1854 mm (72.99″) | 130.3 mm (5.13″) | 1676 mm (65.98″) | 1759 mm (69.25″) | 52 × Ø47.6 mm (1.87″) | 2792 kg | Details → |
ASME B16.47 Series B
ASME B16.47-2025, Series B · North America, Middle East
blind flange · Class 150
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| 26″ | 650 | 786 mm (30.94″) | 42.9 mm (1.69″) | 711 mm (27.99″) | 744.5 mm (29.31″) | 36 × Ø22.2 mm (0.87″) | 170 kg | Details → |
| 28″ | 700 | 837 mm (32.95″) | 46.2 mm (1.82″) | 762 mm (30″) | 795.3 mm (31.31″) | 40 × Ø22.2 mm (0.87″) | 206 kg | Details → |
| 30″ | 750 | 887 mm (34.92″) | 49.2 mm (1.94″) | 813 mm (32.01″) | 846.1 mm (33.31″) | 44 × Ø22.2 mm (0.87″) | 247 kg | Details → |
| 32″ | 800 | 941 mm (37.05″) | 52.6 mm (2.07″) | 864 mm (34.02″) | 900.1 mm (35.44″) | 48 × Ø22.2 mm (0.87″) | 294 kg | Details → |
| 34″ | 850 | 1005 mm (39.57″) | 55.6 mm (2.19″) | 921 mm (36.26″) | 957.3 mm (37.69″) | 40 × Ø25.4 mm (1″) | 355 kg | Details → |
| 36″ | 900 | 1057 mm (41.61″) | 57.2 mm (2.25″) | 972 mm (38.27″) | 1009.6 mm (39.75″) | 44 × Ø25.4 mm (1″) | 404 kg | Details → |
| 38″ | 950 | 1124 mm (44.25″) | 61.9 mm (2.44″) | 1022 mm (40.24″) | 1069.8 mm (42.12″) | 40 × Ø28.6 mm (1.13″) | 494 kg | Details → |
| 40″ | 1000 | 1175 mm (46.26″) | 65.3 mm (2.57″) | 1080 mm (42.52″) | 1120.6 mm (44.12″) | 44 × Ø28.6 mm (1.13″) | 566 kg | Details → |
| 42″ | 1050 | 1226 mm (48.27″) | 66.7 mm (2.63″) | 1130 mm (44.49″) | 1171.4 mm (46.12″) | 48 × Ø28.6 mm (1.13″) | 632 kg | Details → |
| 44″ | 1100 | 1276 mm (50.24″) | 69.9 mm (2.75″) | 1181 mm (46.5″) | 1222.2 mm (48.12″) | 52 × Ø28.6 mm (1.13″) | 716 kg | Details → |
| 46″ | 1150 | 1341 mm (52.8″) | 73.2 mm (2.88″) | 1235 mm (48.62″) | 1284.3 mm (50.56″) | 40 × Ø31.8 mm (1.25″) | 828 kg | Details → |
| 48″ | 1200 | 1392 mm (54.8″) | 76.2 mm (3″) | 1289 mm (50.75″) | 1335.1 mm (52.56″) | 44 × Ø31.8 mm (1.25″) | 928 kg | Details → |
| 50″ | 1250 | 1443 mm (56.81″) | 79.4 mm (3.13″) | 1340 mm (52.76″) | 1385.9 mm (54.56″) | 48 × Ø31.8 mm (1.25″) | 1036 kg | Details → |
| 52″ | 1300 | 1494 mm (58.82″) | 82.6 mm (3.25″) | 1391 mm (54.76″) | 1436.7 mm (56.56″) | 52 × Ø31.8 mm (1.25″) | 1155 kg | Details → |
| 54″ | 1350 | 1549 mm (60.98″) | 85.9 mm (3.38″) | 1441 mm (56.73″) | 1492.2 mm (58.75″) | 56 × Ø31.8 mm (1.25″) | 1292 kg | Details → |
| 56″ | 1400 | 1600 mm (62.99″) | 88.9 mm (3.5″) | 1492 mm (58.74″) | 1543 mm (60.75″) | 60 × Ø31.8 mm (1.25″) | 1427 kg | Details → |
| 58″ | 1450 | 1675 mm (65.94″) | 91.9 mm (3.62″) | 1543 mm (60.75″) | 1611.3 mm (63.44″) | 48 × Ø34.9 mm (1.37″) | 1615 kg | Details → |
| 60″ | 1500 | 1726 mm (67.95″) | 95.3 mm (3.75″) | 1600 mm (62.99″) | 1662.1 mm (65.44″) | 52 × Ø34.9 mm (1.37″) | 1775 kg | Details → |
JIS B2220
JIS B2220:2012 · Japan, Korea, South-East Asia, marine and shipbuilding
blind flange · 10K
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| 10A | 10 | 90 mm | 12 mm | 46 mm | 65 mm | 4 × Ø15 mm | 0.53 kg | Details → |
| 15A | 15 | 95 mm | 12 mm | 51 mm | 70 mm | 4 × Ø15 mm | 0.6 kg | Details → |
| 20A | 20 | 100 mm | 14 mm | 56 mm | 75 mm | 4 × Ø15 mm | 0.79 kg | Details → |
| 25A | 25 | 125 mm | 14 mm | 67 mm | 90 mm | 4 × Ø19 mm | 1.22 kg | Details → |
| 32A | 32 | 135 mm | 16 mm | 76 mm | 100 mm | 4 × Ø19 mm | 1.66 kg | Details → |
| 40A | 40 | 140 mm | 16 mm | 81 mm | 105 mm | 4 × Ø19 mm | 1.79 kg | Details → |
| 50A | 50 | 155 mm | 16 mm | 96 mm | 120 mm | 4 × Ø19 mm | 2.23 kg | Details → |
| 65A | 65 | 175 mm | 18 mm | 116 mm | 140 mm | 4 × Ø19 mm | 3.24 kg | Details → |
| 80A | 80 | 185 mm | 18 mm | 126 mm | 150 mm | 8 × Ø19 mm | 3.48 kg | Details → |
| 90A | 90 | 195 mm | 18 mm | 136 mm | 160 mm | 8 × Ø19 mm | 3.9 kg | Details → |
| 100A | 100 | 210 mm | 18 mm | 151 mm | 175 mm | 8 × Ø19 mm | 4.57 kg | Details → |
| 125A | 125 | 250 mm | 20 mm | 182 mm | 210 mm | 8 × Ø23 mm | 7.18 kg | Details → |
| 150A | 150 | 280 mm | 22 mm | 212 mm | 240 mm | 8 × Ø23 mm | 10.1 kg | Details → |
| 175A | 175 | 305 mm | 22 mm | 237 mm | 265 mm | 12 × Ø23 mm | 11.8 kg | Details → |
| 200A | 200 | 330 mm | 22 mm | 262 mm | 290 mm | 12 × Ø23 mm | 13.9 kg | Details → |
| 225A | 225 | 350 mm | 22 mm | 282 mm | 310 mm | 12 × Ø23 mm | 15.8 kg | Details → |
| 250A | 250 | 400 mm | 24 mm | 324 mm | 355 mm | 12 × Ø25 mm | 22.6 kg | Details → |
| 300A | 300 | 445 mm | 24 mm | 368 mm | 400 mm | 16 × Ø25 mm | 27.8 kg | Details → |
| 350A | 350 | 490 mm | 26 mm | 413 mm | 445 mm | 16 × Ø25 mm | 36.9 kg | Details → |
| 400A | 400 | 560 mm | 28 mm | 475 mm | 510 mm | 16 × Ø27 mm | 52.1 kg | Details → |
| 450A | 450 | 620 mm | 30 mm | 530 mm | 565 mm | 20 × Ø27 mm | 68.4 kg | Details → |
| 500A | 500 | 675 mm | 30 mm | 585 mm | 620 mm | 20 × Ø27 mm | 81.6 kg | Details → |
| 550A | 550 | 745 mm | 34 mm | 640 mm | 680 mm | 20 × Ø33 mm | 112 kg | Details → |
| 600A | 600 | 795 mm | 36 mm | 690 mm | 730 mm | 24 × Ø33 mm | 134 kg | Details → |
EN 1092-1
EN 1092-1:2018 · Europe, UK, Middle East, Africa, CIS projects
blind flange · PN16
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| DN10 | 10 | 90 mm | 16 mm | 40 mm | 60 mm | 4 × Ø14 mm | — | Details → |
| DN15 | 15 | 95 mm | 16 mm | 45 mm | 65 mm | 4 × Ø14 mm | 0.8 kg | Details → |
| DN20 | 20 | 105 mm | 18 mm | 58 mm | 75 mm | 4 × Ø14 mm | 1.1 kg | Details → |
| DN25 | 25 | 115 mm | 18 mm | 68 mm | 85 mm | 4 × Ø14 mm | 1.4 kg | Details → |
| DN32 | 32 | 140 mm | 18 mm | 78 mm | 100 mm | 4 × Ø18 mm | 2 kg | Details → |
| DN40 | 40 | 150 mm | 18 mm | 88 mm | 110 mm | 4 × Ø18 mm | 2.4 kg | Details → |
| DN50 | 50 | 165 mm | 18 mm | 102 mm | 125 mm | 4 × Ø18 mm | 2.9 kg | Details → |
| DN65 | 65 | 185 mm | 18 mm | 122 mm | 145 mm | 8 × Ø18 mm | 3.5 kg | Details → |
| DN80 | 80 | 200 mm | 20 mm | 138 mm | 160 mm | 8 × Ø18 mm | 4.6 kg | Details → |
| DN100 | 100 | 220 mm | 20 mm | 158 mm | 180 mm | 8 × Ø18 mm | 5.7 kg | Details → |
| DN125 | 125 | 250 mm | 22 mm | 188 mm | 210 mm | 8 × Ø18 mm | 8.1 kg | Details → |
| DN150 | 150 | 285 mm | 22 mm | 212 mm | 240 mm | 8 × Ø22 mm | 10.5 kg | Details → |
| DN200 | 200 | 340 mm | 24 mm | 268 mm | 295 mm | 12 × Ø22 mm | 16.2 kg | Details → |
| DN250 | 250 | 405 mm | 26 mm | 320 mm | 355 mm | 12 × Ø26 mm | 25 kg | Details → |
| DN300 | 300 | 460 mm | 28 mm | 378 mm | 410 mm | 12 × Ø26 mm | 35.1 kg | Details → |
| DN350 | 350 | 520 mm | 30 mm | 438 mm | 470 mm | 16 × Ø26 mm | 48 kg | Details → |
| DN400 | 400 | 580 mm | 32 mm | 490 mm | 525 mm | 16 × Ø30 mm | 63.5 kg | Details → |
| DN450 | 450 | 640 mm | 40 mm | 550 mm | 585 mm | 20 × Ø30 mm | — | Details → |
| DN500 | 500 | 715 mm | 44 mm | 610 mm | 650 mm | 20 × Ø33 mm | 133 kg | Details → |
| DN600 | 600 | 840 mm | 54 mm | 725 mm | 770 mm | 20 × Ø36 mm | 226 kg | Details → |
Full rating sets are published on the standard pages: B16.5 · B16.47 A · B16.47 B · JIS B2220 · EN 1092-1 . Tables are compiled from published ASME B16.5-2025, ASME B16.47-2025, Series A, ASME B16.47-2025, Series B, JIS B2220:2012, EN 1092-1:2018 data — verify against the edition named in your purchase specification before quoting a critical part.
Key features
Full pressure rating
Thickness is selected from the B16.5 blind-flange table for the class and size, so the disc carries the rated pressure without a support.
Leak-tight isolation
Face finish and flatness are controlled to seat a spiral-wound or RTJ gasket, giving reliable isolation during maintenance and testing.
Test-point and tie-in options
Centre ports can be drilled and tapped (NPT or BSP) for pressure gauges, venting or hydrostatic testing, with the port size marked on the rim.
Large-diameter capability
B16.47 Series A and B blinds up to 60″ are machined on vertical lathes with dimensional reports for each part.
Typical applications
- Pipeline ends and future tie-in points
- Vessel manways and inspection openings
- Valve and pump isolation during maintenance
- Hydrostatic test closures
- Tank and separator openings
- Temporary blinding during turnaround
Quality control & documentation
- Thickness and flatness measured on every disc
- Bolt-hole pitch and diameter checked against the mating flange
- Face finish verified for the specified gasket type
- MTC 3.1 and heat-number stamping as standard
Material certificates to EN 10204 3.1 are issued with every shipment; third-party inspection (SGS, BV, TÜV) can be arranged on request.
Frequently asked questions
Why is a blind flange thicker than a weld neck flange?
A blind flange has no bore to relieve the pressure load, so the full pressure acts on an unsupported disc in bending. ASME B16.5 therefore specifies a thicker section for blinds than for flanges of the same size and class.
Can a blind flange be drilled and tapped?
Yes. We routinely machine a tapped centre port (NPT or BSP) for pressure testing, venting or gauge connection, and can add a blind boss or weld nipple if required.
What gasket should be used with an RTJ blind?
An RTJ blind needs a matching ring-type joint gasket (soft iron, 316L or other alloy) and a ring groove machined to the correct B16.5 profile. We machine the groove to the class and size and supply the matching gasket on request.
Request a quotation
Send your blind flange specification
Include the standard, size, pressure class, material, face type and quantity. Drawings are welcome — we will confirm feasibility, lead time and price within one business day.
- ★ Reply within 24 hours on business days
- ★ MTC 3.1 and dimensional report with every order
- ★ FOB, CIF and DDP terms available
Send an Inquiry
Send drawings, dimensions or a standard reference. Our sales engineers reply within 24 hours on business days.