FLANGE STANDARD LIBRARYAX FORGE · SPEC SHEET
SPEC SHEETNo. 457
ASME B16.5 · ASME B16.5-2025

B16.5 Class 1500 20″ Weld Neck

DN500Weld NeckDimensions mmWeight kg
ASME B16.5 · 20″ (DN500) · Class 1500 · Weld Neck FlangeASME B16.5 · 20″ (DN500) · Class 1500 · Weld Neck Flange O.D. D 984.3 Bolt circle K 831.9 16ר79.4 Raised face Ø 584.2 Thickness C 177.8 RF height f 6.4 Length H 355.6 Hub Ø A 641.4 Weld end Ø 508.0 Both views share one scale (1:24); schematic only Unit: mm

Schematic — drawn from the table, not to scale for inspection.

SymbolItemValue
DOutside diameter984.3mm
CFlange thickness / blind thickness177.8mm
D2Raised face diameter584.2mm
fRaised face height6.4mm
KBolt circle diameter831.9mm
nNumber of bolt holes16pcs
dBolt hole diameter79.4mm
AHub diameter641.4mm
HHub length / overall length355.6mm
BWelding-end diameter508mm
—Approximate weight930kg

Pressure–temperature ratings · Class 1500 · Group 1.1

≤ 38 °C255.1 bar50 °C248.9 bar100 °C233.5 bar150 °C225.3 bar200 °C219.1 bar250 °C209.8 bar300 °C199.5 bar325 °C193.4 bar350 °C188.2 bar375 °C182.1 bar400 °C173.1 bar425 °C143.7 bar450 °C114.9 bar475 °C87.4 bar500 °C57.6 bar538 °C29.0 bar

Source: Table 2-1.1 (printed p. 25) — pressure–temperature ratings for Group 1.1 materials, SI units; Group 1.1.

Material and notes

Base material: ASTM A105 (North America, Middle East, South-East Asia)

Rating: ASME classes are not fixed pressures. For ASTM A105 (material group 1.1) the ASME B16.5-2025 ambient rating is 285 psi (19.6 bar) at Class 150, 740 psi (51.0 bar) at Class 300, 985 psi (68.0 bar) at Class 400, 1,480 psi (102.0 bar) at Class 600, 2,2…

Tolerances / marking: Tolerances, facing finish, material and marking requirements: ASME B16.5-2025 Sections 6 and 7.

Notes / special requirements

Work order Inspector Date Travels with the part; file after inspection