NDT inspection services
Conventional NDT services
Conventional NDT is the backbone of construction quality control and routine in-service inspection. These methods are fast to mobilise, written into every major code and, applied with the right procedure and coverage, answer most of the questions an inspection programme asks.
Conventional NDT methods
| Method | What it is used for | Key codes |
|---|---|---|
| Visual testing (VT) | Direct and remote visual examination of welds, internals and external condition: the first method on every scope. | ASME V Art. 9, AWS D1.1, API 510/570/653 |
| Liquid penetrant testing (PT) | Surface-breaking flaw detection on non-porous materials, including austenitic stainless and non-ferrous alloys. | ASME V Art. 6, ASTM E165, ISO 3452-1 |
| Magnetic particle testing (MT) | Surface and near-surface flaw detection on ferromagnetic welds and components, including wet fluorescent methods. | ASME V Art. 7, ASTM E709, ISO 9934-1 |
| Ultrasonic testing (UT): thickness and flaw detection | Thickness gauging at CMLs and manual shear-wave weld examination. | ASME V Art. 4/5, ASTM E797, AWS D1.1 |
| Radiographic testing (RT) | Film and digital radiography of welds and components for volumetric flaws. | ASME V Art. 2, ASTM E94, ISO 17636-1 |
| Portable hardness testing | Leeb, UCI and portable Brinell hardness of welds, HAZ and base metal. | ASTM A956, A1038, NACE MR0175/ISO 15156 |
| Positive material identification (PMI) | XRF and OES alloy verification for material verification programmes. | API RP 578, ASTM E1476 |
| Ferrite content testing | Ferrite number measurement of duplex and austenitic stainless welds. | AWS A4.2, ISO 8249 |
| Coating holiday testing | Wet-sponge and high-voltage spark testing of linings and pipeline coatings. | NACE (AMPP) SP0188, SP0274, ASTM D5162 |
| Leak testing | Vacuum box, bubble, pressure-change and helium leak testing. | ASME V Art. 10, API 650/653 |
Surface methods first, then volumetric
Visual testing comes first on every scope and decides where the other methods are needed. Penetrant and magnetic particle testing find surface-breaking flaws; ultrasonic and radiographic testing look through the wall. Material checks (PMI, hardness and ferrite) confirm the steel is what the design assumed, and holiday and leak testing confirm that coatings and joints are tight.
Acceptance criteria are set before the work
Each method is applied to a procedure that names the code and edition, the technique and the acceptance criteria. Indications are reported against those criteria, with photographs or sketches where they help the engineer reading the report.
Frequently asked questions
Is PT or MT better for weld inspection?
MT is preferred on ferromagnetic steels because it also finds some near-surface flaws and needs less surface preparation. PT is used on non-magnetic materials such as austenitic stainless steel and aluminium.
Talk to an inspection engineer
Send the equipment list or drawings, the inspection you need and your timing. Quotes are prepared for each scope and region.
Request a QuoteRequest an inspection quote (RFQ)
Tell us the asset, the method, where it is, the governing code, your dates, the size of the job and the report you need. We reply with questions or a quote. Affordable, accessible, fully customizable — no published pricing.
Or email the same details to info@atlantisndt.com. Mobilisation: North America; confirm your location in your RFQ.
Speak to an ASNT NDT Level III
Atlantis NDT provides ASNT Level III consulting, NDT training to ASNT SNT-TC-1A, inspection management software and independent report validation. Request a free consultation and we will return a tailored quote — affordable, accessible and fully customizable to your programme.