Atmospheric Storage Tank — EN 14015 — Applicable Engineering Standards & Codes

Description

European equivalent of API 650 — vertical, cylindrical, flat-bottomed atmospheric tank.

API 650 Welded Tanks for Oil Storage

Edition: 13th Edition (2020, A1 2021, A2 2023) Region: USA, Global

Atmospheric, vertical, cylindrical above-ground welded steel tanks for liquid storage.

Key requirements (11)

Atmospheric tanks — design pressure –0.25 in WC to 2.5 psig (≈17 mbar) max.
Design temperature: ambient up to 93 °C (200 °F); higher → API 620 Annex M.
Bottom plate min thickness: 6 mm (1/4") nominal.
Shell design: 1-foot method (Section 5.6.3) or variable design point (5.6.4).
Joint efficiency: 0.85 (lap-welded) or 1.0 (butt-welded with full RT).
Hydrotest: filled with water to design liquid level; 24-hour holding test.
Wind girders / top angle stiffeners: Section 5.9.6.
Annex E: seismic; Annex C: external floating roof; Annex H: internal floating roof.
Annex F: internal pressure up to 18 in WC; Annex M: elevated temperature; Annex S: stainless.
Default allowable stress: 2/3 yield or 2/5 UTS (whichever lower) at design temp.
Foundation: Annex B guidance (ringwall, slab, piled).

Note: Default global standard for atmospheric oil/petroleum storage tanks.

API 653 Tank Inspection, Repair, Alteration, and Reconstruction

Edition: 5th Edition (2014, A3 2020) Region: USA, Global

In-service inspection and repair of API 650 and 12C tanks.

Key requirements (7)

Applies to API 650 / API 12C atmospheric storage tanks in service.
External inspection ≤ 5 years; internal ≤ 10 years (extendable via RBI to 15–20 yr).
Bottom MFL/UT scanning during internal inspection — quantifies underside corrosion.
Settlement survey at intervals (cosine-curve fit, edge settlement criteria).
Reconstruction: hydrotest required after major shell replacement.
Authorized Tank Inspector (API 653 ICP) required.
Repairs categorized as 'Major Alteration', 'Repair' or 'Routine Maintenance' with different documentation.

EN 14015 Site built, vertical, cylindrical, flat-bottomed, above ground welded steel tanks for storage of liquids at ambient temperature and above

Edition: 2004 (under revision) Region: Europe

European equivalent of API 650.