Download NAV MT Naval Shipbuilders NDT III Specific Magnetic Particle Testing Exam and more Exams Technology in PDF only on Docsity!
Specific Magnetic Particle Testing
Exam
Question 1. What is the primary standard document used for Magnetic Particle Testing (MT) procedures on naval components according to NAVSEA requirements? A) ASTM E B) T9074-AS-GIB-010/ C) ASME Section V D) MIL-STD- 2132 Answer: B Explanation: T9074-AS-GIB-010/271 is the NAVSEA-specific document that provides detailed requirements for Magnetic Particle Testing on naval components, including procedures, acceptance criteria, and reporting.
Specific Magnetic Particle Testing
Exam
Question 2. Which of the following best describes the role of a Level III NDT personnel in naval shipbuilding? A) Perform all testing without supervision B) Develop, approve, and oversee NDT procedures and personnel qualifications C) Only operate testing equipment under supervision D) Conduct only visual inspections Answer: B Explanation: Level III NDT personnel are responsible for developing, qualifying, and approving inspection procedures, as well as overseeing personnel certification and ensuring compliance with standards.
Specific Magnetic Particle Testing
Exam
A) 10-20 A/m B) 50-100 A/m C) 200-400 A/m D) 1000-2000 A/m Answer: C Explanation: A magnetic field strength of approximately 200-400 A/m is generally recommended for high-strength steel welds to ensure adequate sensitivity for discontinuity detection. Question 5. When inspecting a dissimilar metal weld, what must be considered regarding magnetic field direction? A) It should be parallel to the weld axis only
Specific Magnetic Particle Testing
Exam
B) It should be perpendicular to the weld surface only C) It must be optimized to cover all possible discontinuity orientations D) It is not important for dissimilar welds Answer: C Explanation: Proper magnetic field orientation is critical, especially in dissimilar welds, to detect discontinuities in all possible orientations, requiring multiple magnetization techniques or directions. Question 6. Which of the following is a common discontinuity that can be identified through magnetic particle testing? A) Crater cracks B) Void porosity
Specific Magnetic Particle Testing
Exam
D) Painting over the inspection area Answer: C Explanation: Proper surface preparation involves cleaning to remove contaminants that could mask indications or interfere with magnetic particle adherence and detection. Question 8. Which magnetization method is best suited for inspecting large, complex-shaped castings like valves or turbine components? A) Head shot magnetization B) Coil magnetization C) Prods (yoke) magnetization D) Multidirectional magnetization
Specific Magnetic Particle Testing
Exam
Answer: D Explanation: Multidirectional magnetization is most effective for large and complex geometries to ensure all discontinuities are detectable regardless of orientation. Question 9. During in-service inspections, which technique is often used for inspecting welded joints in confined spaces on ships? A) Visual inspection only B) Remote or portable MT equipment with suitable magnetization methods C) Ultrasonic testing exclusively D) Radiography only Answer: B
Specific Magnetic Particle Testing
Exam
Explanation: Demagnetization reduces residual magnetic fields to prevent magnetic interference with sensitive equipment and to avoid magnetically induced issues during operation. Question 11. Which of the following is a requirement for an approved magnetic particle inspection procedure according to NAVSEA standards? A) Use of any magnetic particles available B) Clear description of magnetic field application, equipment, and sensitivity criteria C) No documentation or qualification necessary D) Use of only dry magnetic particles Answer: B
Specific Magnetic Particle Testing
Exam
Explanation: An approved procedure must specify the magnetic field application method, equipment, particle type, sensitivity level, and be qualified through demonstration. Question 12. Which specification governs the certification of magnetic particle materials used in naval shipbuilding? A) ASTM E B) MIL-STD- 2132 C) NAVSEA Standard Items D) Military and federal standards, with certification of particle batch and suspension medium Answer: D
Specific Magnetic Particle Testing
Exam
Explanation: Lack of fusion indicates an incomplete weld where the weld metal has not properly fused with the base metal, which can be critical and detectable via MT. Question 14. When inspecting a socket weld with magnetic particle testing, what is an important consideration regarding the magnetic field? A) It must be directed parallel to the weld axis B) It must be oriented to detect surface cracks at the weld toe C) It is not applicable to socket welds D) It should be minimized for better indications Answer: B
Specific Magnetic Particle Testing
Exam
Explanation: Proper orientation of the magnetic field is critical in socket welds to detect surface cracks or discontinuities at the weld toe, often requiring multiple directions. Question 15. Which equipment is commonly used for applying magnetic fields in magnetic particle testing? A) Ultrasonic probes B) Magnetic yokes, coils, and prods C) Radiographic sources D) Eddy current devices Answer: B Explanation: Magnetic yokes, coils, and prods are standard equipment used to generate magnetic fields for MT inspections.
Specific Magnetic Particle Testing
Exam
Question 17. What is the typical purpose of a "demagnetization" process in magnetic particle testing? A) To magnetize the component further B) To remove residual magnetic fields after inspection C) To increase the magnetic flux D) To sterilize the component surface Answer: B Explanation: Demagnetization removes residual magnetic fields that could interfere with equipment operation or cause magnetic attraction issues. Question 18. Which type of magnetic particle is most suitable for detecting very fine surface discontinuities?
Specific Magnetic Particle Testing
Exam
A) Dry particles B) Wet suspension particles with small particle size C) Large, coarse particles D) Powdered ferrous filings only Answer: B Explanation: Fine, wet suspension particles are most effective for detecting small, surface-breaking discontinuities due to their ability to form sharp indications. Question 19. In the context of procedural development, what is a "technique sheet"? A) A detailed drawing of the component
Specific Magnetic Particle Testing
Exam
B) It ensures the accuracy of magnetic field strength and equipment functionality C) It only applies to ultrasonic equipment D) It is only necessary during initial setup and not regularly Answer: B Explanation: Calibration ensures that the equipment produces the correct magnetic field strength and functions properly, which is essential for reliable and valid inspection results. Question 21. What is the primary purpose of an inspection report in naval NDT? A) To record personnel attendance
Specific Magnetic Particle Testing
Exam
B) To document inspection results, indications, equipment calibration data, and personnel qualifications for traceability C) To serve as a safety hazard report D) To provide a general overview of the component design Answer: B Explanation: Inspection reports serve as official documentation of the findings, including indications, equipment calibration, personnel certifications, and traceability for quality assurance. Question 22. Which of the following is a typical minimum qualification requirement for Level I MT personnel in a naval shipyard? A) No formal training required
