ASME B16.47 Series B · ASTM A105 · stock and made to order
50″ Class 300 Blind Flange — ASME B16.47 Series B
50″ Class 300 blind flange to ASME B16.47 Series B, machined from ASTM A105. Outside diameter 1562 mm, thickness 138.1 mm, 44 bolt holes on a 1466.8 mm circle, approximate weight 2100 kg. Available with raised face, flat face or the facing specified on your drawing.
Size
50″ / DN1250
Standard
ASME B16.47 Series B (ASME B16.47-2025, Series B)
Pressure rating
Class 300
Outside diameter
1562 mm (61.5″)
Thickness
138.1 mm (5.44″)
Bolt circle
1466.8 mm (57.75″)
Approx. weight
2100 kg
Full dimensions — 50″ Class 300
| Size | DN | OD | Thickness | RF Ø | Bolt circle | Bolts | Weight | |
|---|---|---|---|---|---|---|---|---|
| 26″ | 650 | 867 mm (34.13″) | 87.3 mm (3.44″) | 737 mm (29.02″) | 803.1 mm (31.62″) | 32 × Ø34.9 mm (1.37″) | 411 kg | Details → |
| 28″ | 700 | 921 mm (36.26″) | 87.3 mm (3.44″) | 787 mm (30.98″) | 857.2 mm (33.75″) | 36 × Ø34.9 mm (1.37″) | 464 kg | Details → |
| 30″ | 750 | 991 mm (39.02″) | 92.1 mm (3.63″) | 845 mm (33.27″) | 920.8 mm (36.25″) | 36 × Ø38.1 mm (1.5″) | 567 kg | Details → |
| 32″ | 800 | 1054 mm (41.5″) | 101.6 mm (4″) | 902 mm (35.51″) | 977.9 mm (38.5″) | 32 × Ø41.3 mm (1.63″) | 706 kg | Details → |
| 34″ | 850 | 1108 mm (43.62″) | 101.6 mm (4″) | 952 mm (37.48″) | 1031.7 mm (40.62″) | 36 × Ø41.3 mm (1.63″) | 780 kg | Details → |
| 36″ | 900 | 1171 mm (46.1″) | 101.6 mm (4″) | 1010 mm (39.76″) | 1089.2 mm (42.88″) | 32 × Ø44.5 mm (1.75″) | 871 kg | Details → |
| 38″ | 950 | 1222 mm (48.11″) | 109.5 mm (4.31″) | 1060 mm (41.73″) | 1140 mm (44.88″) | 36 × Ø44.5 mm (1.75″) | 1024 kg | Details → |
| 40″ | 1000 | 1273 mm (50.12″) | 114.3 mm (4.5″) | 1115 mm (43.9″) | 1190.8 mm (46.88″) | 40 × Ø44.5 mm (1.75″) | 1157 kg | Details → |
| 42″ | 1050 | 1334 mm (52.52″) | 117.5 mm (4.63″) | 1168 mm (45.98″) | 1244.6 mm (49″) | 36 × Ø47.6 mm (1.87″) | 1304 kg | Details → |
| 44″ | 1100 | 1384 mm (54.49″) | 125.4 mm (4.94″) | 1219 mm (47.99″) | 1295.4 mm (51″) | 40 × Ø47.6 mm (1.87″) | 1499 kg | Details → |
| 46″ | 1150 | 1460 mm (57.48″) | 128.6 mm (5.06″) | 1270 mm (50″) | 1365.2 mm (53.75″) | 36 × Ø50.8 mm (2″) | 1708 kg | Details → |
| 48″ | 1200 | 1511 mm (59.49″) | 133.4 mm (5.25″) | 1327 mm (52.24″) | 1416 mm (55.75″) | 40 × Ø50.8 mm (2″) | 1897 kg | Details → |
| 50″ (this size) | 1250 | 1562 mm (61.5″) | 138.1 mm (5.44″) | 1378 mm (54.25″) | 1466.8 mm (57.75″) | 44 × Ø50.8 mm (2″) | 2100 kg | Details → |
| 52″ | 1300 | 1613 mm (63.5″) | 142.5 mm (5.61″) | 1429 mm (56.26″) | 1517.6 mm (59.75″) | 48 × Ø50.8 mm (2″) | 2312 kg | Details → |
| 54″ | 1350 | 1673 mm (65.87″) | 147.6 mm (5.81″) | 1480 mm (58.27″) | 1577.8 mm (62.12″) | 48 × Ø50.8 mm (2″) | 2576 kg | Details → |
| 56″ | 1400 | 1765 mm (69.49″) | 155.4 mm (6.12″) | 1537 mm (60.51″) | 1651 mm (65″) | 36 × Ø60.3 mm (2.37″) | 3013 kg | Details → |
| 58″ | 1450 | 1827 mm (71.93″) | 160.3 mm (6.31″) | 1594 mm (62.76″) | 1712.9 mm (67.44″) | 40 × Ø60.3 mm (2.37″) | 3333 kg | Details → |
| 60″ | 1500 | 1878 mm (73.94″) | 165.1 mm (6.5″) | 1651 mm (65″) | 1763.7 mm (69.44″) | 40 × Ø60.3 mm (2.37″) | 3620 kg | Details → |
Published ASME B16.47 Series B dimensions for every Class 300 size in this product family.
Dimensions in millimetres; the inch equivalent is shown in brackets. Bolt hole diameter applies to through-holes. For stud length, gasket and bolting selection, match the gasket and bolts to B16.47 B.
What Class 300 means in service
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.
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.
Facing and materials
Raised face (RF) is standard: 1.5 mm high for Classes 75, 150 and 300; 6.4 mm for Classes 400, 600 and 900. FF and RTJ faces are available to drawing.
- ASTM A105 / A105N
- ASTM A350 LF2
- ASTM A182 F304/F316L
- ASTM A694 F52/F60/F65
- ASTM A182 F51/F53
Other grades, impact-tested heats and NACE MR0175 requirements are quoted on request. Material certificates to EN 10204 3.1 are issued against the same heat number as the dimensional report.
Inspection and delivery
- Dimensional inspection against the B16.47 B table for 50″ Class 300
- Heat number stamped on the rim; EN 10204 3.1 certificate issued
- PMI on stainless and alloy heats; UT/RT on request
- Anti-rust oil, plywood case or pallet, with packing list and MTC
- Typical lead time 7–15 days for carbon steel stock sizes, 20–30 days for alloys
Other sizes in Class 300
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50″ Class 300 Blind Flange
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