Eddy Current Testing in Refining: What It Finds, What It Misses, and What Governs It
What ET is actually used for in refining
Refinery exchanger bundles are examined with eddy current at every major turnaround — bobbin screening for wall loss across thousands of non-ferrous tubes, with array or rotating probes on the indications that matter.
How ET works
Eddy current testing induces circulating currents in a conductive material and reads the impedance change a discontinuity causes. It needs no couplant and no contact, which makes it the fastest surface and near-surface method available — and, in tube form, the only practical way to screen thousands of heat-exchanger tubes inside a shutdown window.
What ET will not do
What ET will not do: examine non-conductive material, penetrate deeply (the effect is confined near the surface, more so as frequency rises), or produce results anyone can interpret without training — signal interpretation is the whole skill, and lift-off, edge effects and permeability variation all masquerade as indications.
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 8 for tubing; ASTM E243 and E571 for specific product forms; aerospace surface examination runs under NAS 410 with OEM technique requirements. 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 ET 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.
Eddy Current Testing services · ET training and certification · Refining programme consulting · Refining NDT training · scope a ET examination.
ET in other sectors
Petrochemical · LNG · Offshore · Pipeline · Marine & Shipbuilding · Aviation & Aerospace.