Magnetic Particle Testing in LNG: What It Finds, What It Misses, and What Governs It
What MT is actually used for in lng
Carbon steel structures around LNG trains — pipe racks, module steel, tank bases — take MT on their welds, while the cryogenic alloys themselves fall to penetrant instead.
How MT works
MT magnetises a ferromagnetic component and applies iron particles, which gather at the flux leakage a surface-breaking or near-surface discontinuity creates. It is fast, inexpensive per square metre, and unusually good at what it does: finding cracks in steel that a visual examination would miss.
What MT will not do
What MT will not do: work on non-magnetic material at all — no stainless austenitics, no aluminium, no nickel alloys — and it finds nothing meaningfully below the surface. Coatings degrade sensitivity, and flaws parallel to the flux direction are invisible, which is why examination in two directions is standard practice rather than diligence.
The lng assets this applies to
Liquefaction trains, cryogenic storage tanks, loading lines and jetties, boil-off handling, and the marine interface.
The damage mechanisms driving the examination
Cryogenic service changes the question: brittle fracture risk drives material and toughness concerns, thermal cycling fatigues connections, and external corrosion under cryogenic insulation is difficult to detect precisely because access is difficult.
What governs acceptance
API 625 and 620 for cryogenic tanks, ASME for pressure equipment, plus jurisdictional and marine-terminal requirements at the interface. On the method side: ASME Section V Article 7; AWS D1.1 for structural work; ASTM E1444 in aerospace and general industry; ASTM E709 as the practice reference. 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 MT 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.
Magnetic Particle Testing services · MT training and certification · LNG programme consulting · LNG NDT training · scope a MT examination.
MT in other sectors
Refining · Petrochemical · Offshore · Pipeline · Marine & Shipbuilding · Aviation & Aerospace.