Magnetic Particle Testing in Marine & Shipbuilding: What It Finds, What It Misses, and What Governs It
What MT is actually used for in marine & shipbuilding
Class surveys call MT on hatch corners, crane pedestals, rudder horns and other fatigue-prone details, where the finding decides steel renewal scope.
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 marine & shipbuilding assets this applies to
Hull structure and plating, ballast and cargo tanks, propulsion and shafting, deck machinery, and the yard's own new-construction welding.
The damage mechanisms driving the examination
Fatigue at structural details, corrosion in ballast spaces and at the waterline, coating breakdown, and construction defects that surface as in-service cracking.
What governs acceptance
Classification societies (ABS above all in US work) for commercial survey and acceptance; NAVSEA technical publications on naval work, with qualification layered over SNT-TC-1A. 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 · Marine & Shipbuilding programme consulting · Marine & Shipbuilding NDT training · scope a MT examination.
MT in other sectors
Refining · Petrochemical · LNG · Offshore · Pipeline · Aviation & Aerospace.