Start with the inspection question
Define what decision the result must support. Are you looking for a surface crack, a near-surface indication, an internal reflector, wall loss, or visible workmanship and dimensional conditions? A precise objective prevents unnecessary testing.
Visual testing (VT)
Use VT to assess accessible surface condition, weld fit-up, profile, dimensions and visible discontinuities. It is often the first examination and may identify areas that need another method.
Magnetic particle testing (MT)
Use MT for surface and near-surface discontinuities in ferromagnetic materials. It is a strong choice for many carbon-steel welds, forgings, castings and structural components, but not for aluminum or other non-ferromagnetic materials.
Liquid penetrant testing (PT)
Use PT for discontinuities open to the surface on suitable non-porous materials. It works on many ferrous and non-ferrous materials, including aluminum and stainless steel, but cannot reveal a fully internal flaw.
Ultrasonic testing (UT)
Use conventional UT when the objective involves suitable internal examination or thickness measurement. Material structure, geometry, surface condition, thickness and flaw orientation influence whether UT can answer the question.
Sometimes the answer is more than one method
Methods often complement one another. VT may establish surface condition, MT or PT may increase sensitivity to surface-breaking flaws, and UT may address suitable internal conditions. Applicable project requirements remain authoritative.
Discuss your inspection requirement
This guide is general information, not a substitute for applicable project requirements or a qualified review of the actual component. Contact VeriTech with the material, geometry, access and inspection objective to discuss an appropriate scope.