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BSI

PD 5500

Specification for unfired fusion welded pressure vessels

Issuing body
BSI
Latest edition
2021
Region
UK, Europe
Equipment items
1

Scope

British pressure vessel code (formerly BS 5500); often used in Commonwealth countries.

Key requirements (7)

  • British Standard for unfired fusion-welded pressure vessels (Cat 1 / Cat 2 / Cat 3).
  • Cat 1 = full RT, Cat 2 = partial RT, Cat 3 = visual + limited NDT.
  • Design factor f = lower of UTS/2.35 and Yield/1.5 at design temperature.
  • Hydrotest: 1.25 × design pressure (Cat 1) or 1.5 × design pressure (Cat 2/3).
  • Annex D: design by analysis (FEA) — alternative to formula-based design.
  • Annex G: vessel-on-saddle stress analysis (Zick analysis).
  • Used widely in UK, Middle East, India for non-nuclear vessels.

Related standards (2)

Applied to 1 equipment item

Pressure Vessels & Reactors