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ASME B16.47 Series B · ASTM A105 · stock and made to order

34″ Class 400 Blind Flange — ASME B16.47 Series B

34″ Class 400 blind flange to ASME B16.47 Series B, machined from ASTM A105. Outside diameter 1086 mm, thickness 111.3 mm, 32 bolt holes on a 1003.3 mm circle, approximate weight 807 kg. Available with raised face, flat face or the facing specified on your drawing.

Technical drawing of a 34″ Class 400 blind flange, ASME B16.47 Series B
Dimensioned drawing supplied with the quotation and the inspection report.

Size

34″ / DN850

Standard

ASME B16.47 Series B (ASME B16.47-2025, Series B)

Pressure rating

Class 400

Outside diameter

1086 mm (42.76″)

Thickness

111.3 mm (4.38″)

Bolt circle

1003.3 mm (39.5″)

Approx. weight

807 kg

Full dimensions — 34″ Class 400

Size DN OD Thickness RF Ø Bolt circle Bolts Weight
26″ 650 851 mm (33.5″) 88.9 mm (3.5″) 711 mm (27.99″) 781 mm (30.75″) 28 × Ø38.1 mm (1.5″) 397 kg Details →
28″ 700 914 mm (35.98″) 95.3 mm (3.75″) 762 mm (30″) 838.2 mm (33″) 24 × Ø41.3 mm (1.63″) 490 kg Details →
30″ 750 972 mm (38.27″) 101.6 mm (4″) 819 mm (32.24″) 895.4 mm (35.25″) 28 × Ø41.3 mm (1.63″) 591 kg Details →
32″ 800 1035 mm (40.75″) 108 mm (4.25″) 873 mm (34.37″) 952.5 mm (37.5″) 28 × Ø44.5 mm (1.75″) 712 kg Details →
34″ (this size) 850 1086 mm (42.76″) 111.3 mm (4.38″) 927 mm (36.5″) 1003.3 mm (39.5″) 32 × Ø44.5 mm (1.75″) 807 kg Details →
36″ 900 1156 mm (45.51″) 119.1 mm (4.69″) 981 mm (38.62″) 1066.8 mm (42″) 28 × Ø47.6 mm (1.87″) 980 kg Details →
38″ 950 1206 mm (47.48″) 124 mm (4.88″) 1035 mm (40.75″) 1117.6 mm (44″) 32 × Ø47.6 mm (1.87″) — Details →
40″ 1000 1270 mm (50″) 130 mm (5.12″) 1092 mm (42.99″) 1174.8 mm (46.25″) 32 × Ø50.8 mm (2″) — Details →
42″ 1050 1321 mm (52.01″) 133.4 mm (5.25″) 1143 mm (45″) 1225.6 mm (48.25″) 32 × Ø50.8 mm (2″) — Details →
44″ 1100 1384 mm (54.49″) 139.7 mm (5.5″) 1200 mm (47.24″) 1282.7 mm (50.5″) 32 × Ø54 mm (2.13″) — Details →
46″ 1150 1441 mm (56.73″) 146.1 mm (5.75″) 1257 mm (49.49″) 1339.8 mm (52.75″) 36 × Ø54 mm (2.13″) — Details →
48″ 1200 1511 mm (59.49″) 152.4 mm (6″) 1308 mm (51.5″) 1403.4 mm (55.25″) 28 × Ø60.3 mm (2.37″) — Details →
50″ 1250 1568 mm (61.73″) 158.8 mm (6.25″) 1362 mm (53.62″) 1460.5 mm (57.5″) 32 × Ø60.3 mm (2.37″) — Details →
52″ 1300 1619 mm (63.74″) 163.5 mm (6.44″) 1413 mm (55.63″) 1511.3 mm (59.5″) 32 × Ø60.3 mm (2.37″) — Details →
54″ 1350 1702 mm (67.01″) 171.5 mm (6.75″) 1470 mm (57.87″) 1581.2 mm (62.25″) 28 × Ø66.7 mm (2.63″) — Details →
56″ 1400 1753 mm (69.02″) 176.2 mm (6.94″) 1527 mm (60.12″) 1632 mm (64.25″) 32 × Ø66.7 mm (2.63″) — Details →
58″ 1450 1803 mm (70.98″) 180.8 mm (7.12″) 1578 mm (62.13″) 1682.8 mm (66.25″) 32 × Ø66.7 mm (2.63″) — Details →
60″ 1500 1886 mm (74.25″) 188.9 mm (7.44″) 1635 mm (64.37″) 1752.6 mm (69″) 32 × Ø73 mm (2.87″) — Details →

Published ASME B16.47 Series B dimensions for every Class 400 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 400 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 34″ Class 400
  • 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 400

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34″ Class 400 Blind Flange

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