Ultrasonic Testing in Refining: What It Finds, What It Misses, and What Governs It
What UT is actually used for in refining
In refining, UT is the backbone of the corrosion programme — thickness monitoring at condition monitoring locations across crude, vacuum and coker circuits, shear-wave and phased array on repair welds, and high-temperature techniques where insulation cannot come off.
How UT works
Ultrasonic testing sends high-frequency sound into the material and times what comes back. Because sound reflects at any interface where acoustic impedance changes — a back wall, a lamination, the face of a crack — UT measures remaining wall thickness and finds planar defects that other methods cannot see, from one accessible surface.
What UT will not do
What UT will not do: it needs coupling to the surface, so paint, scale and severe roughness degrade it; it struggles with coarse-grained and austenitic material where the grain scatters the beam; and it is orientation-sensitive — a planar flaw lying parallel to the beam can be missed entirely, which is why technique and scan plan matter more than instrument quality.
The refining assets this applies to
Crude and vacuum units, cokers, reformers, hydrotreaters, the piping circuits between them, fired heaters, exchanger trains, and the tank farm at the end of it.
The damage mechanisms driving the examination
Corrosion is the governing story — sulphidic and naphthenic attack on hot circuits, aqueous corrosion in overheads, corrosion under insulation everywhere insulation exists — with wet H2S cracking, high-temperature hydrogen attack and creep in specific services.
What governs acceptance
API 510 (vessels), 570 (piping) and 653 (tanks) govern in-service inspection, with ASME Section V supplying method rules and Section VIII / B31.3 the acceptance criteria. Operator contractor-approval gates site access above the codes. On the method side: ASME Section V Article 4 supplies the method rules most referencing codes point at; AWS D1.1 governs structural weld acceptance; API 5xx in-service codes govern thickness evaluation and remaining-life calculation. An examination that is technically sound but performed outside the governing regime is not an examination anyone will accept, which is why the code family matters as much as the technique.
How Atlantis delivers UT in this sector
Atlantis mobilises examination teams to your site under Atlantis procedures with ASNT Level III oversight — we do not claim a depot or laboratory in every market, and say so plainly. What you receive is the examination performed to a qualified procedure, findings evaluated against the acceptance criteria your contract names, and records structured to survive a client audit years later.
Ultrasonic Testing services · UT training and certification · Refining programme consulting · Refining NDT training · scope a UT examination.
UT in other sectors
Petrochemical · LNG · Offshore · Pipeline · Marine & Shipbuilding · Aviation & Aerospace.