What are the types of non-destructive testing?
Short answer
| Method | Principle | Detects | Material Suitability | Key Limitation |
|---|---|---|---|---|
| VT | Visual observation | Surface defects, corrosion, profile | All | Surface only, access needed |
| RT | Ionising radiation | Internal flaws (porosity, cracks) | All | Radiation hazard, thickness limits |
| UT | Ultrasonic reflection | Internal/surface flaws, thickness | All | Needs coupling, skilled interpretation |
| MT | Magnetic flux leakage | Surface/near-surface cracks | Ferromagnetic only | Ferromagnetic materials only |
| PT | Capillary action | Surface-breaking defects | Non-porous | Surface only, clean surface required |
| ET | Electromagnetic induction | Surface/near-surface defects | Conductive only | Conductive materials only |
- Definition: Technical methods to examine materials/components without impairing future use
- Purpose: Detect, locate, measure, evaluate flaws and geometrical characteristics
- Ship use: Construction, surveys, repairs, maintenance for structural integrity and class compliance
- Core methods (UR W33): Visual Testing (VT), Radiographic Testing (RT), Ultrasonic Testing (UT), Magnetic Particle Testing (MT), Penetrant Testing (PT)
- Advanced methods (UR W35): Electromagnetic Testing (ET), Digital Radiography (RT-D), Phased Array Ultrasonic Testing (PAUT), Time-of-Flight Diffraction (TOFD), Automated Ultrasonic Testing (AUT)
- Timing and criteria: UR W33 §2.4 (timing), §7.1.1 (acceptance criteria)
- Personnel and suppliers: UR W35 qualification requirements
- Second Engineer duties: Verify plan compliance, check personnel qualifications, review reports, maintain records, escalate non-conformities
Full answer
The full answer explains each point step by step, with the regulations and figures behind it and the discussion from other candidates. It is in the MEO Class II section of the Marine One forum, open to members enrolled for the MEO Class II exam.