Radiographic Testing in LNG: What It Finds, What It Misses, and What Governs It
What RT is actually used for in lng
LNG construction is radiography-heavy: tank shell courses, cryogenic piping and module fabrication welds are examined to demanding acceptance criteria with records kept for the facility life.
How RT works
Radiography passes X-rays or gamma radiation through the component onto film or a digital detector. Density differences in the image reveal what the material contains — porosity, slag, lack of fusion, and the internal geometry of a weld — producing the one thing no other method gives: a permanent, reviewable image of the volume examined.
What RT will not do
What RT will not do reliably: find tight planar defects lying perpendicular to the beam, because a crack with no measurable width casts almost no shadow. It also requires access to both sides, controlled radiation areas that shut down surrounding work, and licensed sources — which is why RT is scheduled around the plant rather than the plant around RT.
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 Articles 2 and 22 for technique; ASME Section VIII and B31.3 for acceptance; API 1104 for pipeline girth welds; ISO 17636 in international scopes. 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 RT 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.
Radiographic Testing services · RT training and certification · LNG programme consulting · LNG NDT training · scope a RT examination.
RT in other sectors
Refining · Petrochemical · Offshore · Pipeline · Marine & Shipbuilding · Aviation & Aerospace.