12 Interview Question related to Non- destructive Testing

1.What is NDT?
Answer :- NDT stands for non-destructive testing. NDT is a type of testing that is used to evaluate the properties of a material, component, or system without causing damage.
NDT is important because it allows for the evaluation of materials, components, and systems without causing any damage. This type of testing is used in a variety of industries, including the aerospace, automotive, and construction industries. NDT is also used in the inspection of critical components, such as turbine blades and pressure vessels.
Example: “NDT is a branch of engineering that deals with the assessment and testing of materials and components without causing damage. It is used in a variety of industries, including aerospace, automotive, construction and manufacturing. NDT methods include visual inspection, ultrasonic testing, X-ray testing and magnetic particle inspection.”

2. Describe different types of destructive and non-destructive tests?
Answer: -
DESTRUCTIVE TEST: Bend test, Tensile test, Impact test, and Hardness test.
NON-DESTRUCTIVE TEST: DPT, MPT, Radiography and ultrasonic test.

3. What are the benefits of NDT?
Answer :- “NDT provides many benefits to various industries, including the aerospace, automotive, and manufacturing sectors. NDT helps to ensure the safety and quality of products and components by allowing for the detection of defects and flaws that could otherwise lead to failure or malfunction. In addition, NDT can be used to assess the strength and integrity of materials and structures, as well as to monitor the progress of manufacturing processes. By providing accurate and reliable information about the condition of products and components, NDT can help to improve efficiency and reduce costs.”
 

4. What is the relation between Brinell Hardness No. and Rockwell Hardness No.?
Answer: -

22 HRC (Rockwell Hardness) = 238 BHN (Brinell Hardness No) Harder.

5.What is the principal of ultrasonic testing?
Answer :- Ultrasonic testing uses high frequency sound waves to detect flaws or measure thickness in materials.

• Ultrasonic waves are sent into the material being tested
• The waves bounce back differently depending on the material's thickness or any flaws present
• The reflected waves are analyzed to determine the material's properties
• Commonly used in non-destructive testing of metals, plastics, and composites.

6. What is the meaning of ultrasonic testing and why we do ultrasonic testing and describe the procedure of ultrasonic testing.
Answer :- Ultrasonic testing is a non-destructive testing method that uses high-frequency sound waves to detect flaws or defects in materials.

• Ultrasonic testing is used to detect internal flaws or defects in materials such as cracks, voids, and inclusions.
• The procedure involves sending high-frequency sound waves through the material and measuring the time it takes for the waves to bounce back.
• The reflected waves are then analyzed to determine the location and size of any defects.
• Ultrasonic testing is commonly used in industries such as aerospace, automotive, and manufacturing.
• It is also used in medical imaging to visualize internal organs and tissues.

7.What is the role of an NDT Technician?
Answer :- “An NDT Technician is responsible for the inspection of materials and components using nondestructive testing methods. They work with a variety of equipment and techniques to detect surface and subsurface defects in metals, composites, plastics, and other materials. NDT Technicians typically work in manufacturing or repair facilities, but may also be employed in the oil and gas industry, aerospace industry, or other industries where safety and quality are critical concerns.”

8. What skills are necessary to be an effective NDT Technician?
Answer :- “The skills necessary to be an effective NDT Technician include:

• The ability to read and interpret engineering drawings and specifications
• A working knowledge of physics and mathematics
• The ability to use a variety of NDT methods and equipment
• The ability to write clear and concise reports
• The ability to work independently or as part of a team”.

9. what is the procedure of LPT and principal of Dp?
Answer :- LPT is Liquid Penetrant Testing used to detect surface defects. DP is Differential Pressure used to measure flow rate.

• LPT involves applying a liquid penetrant to the surface of a material and then removing the excess to reveal any surface defects.
• DP measures the difference in pressure between two points in a system to determine the flow rate.
• DP can be used in various applications such as measuring the flow rate of fluids in pipes or detecting leaks in a system.
• Both LPT and DP are non-destructive testing methods used in industries such as aerospace, automotive, and manufacturing.

10. What is the acceptance cateria of UT ?
Answer :- Acceptance criteria of UT refers to the minimum standards that a material or component must meet to be considered acceptable for use.

• The acceptance criteria of UT is based on the size, shape, and location of the defects found in the material or component being inspected.
• The criteria may vary depending on the industry and application of the material or component.
• The acceptance criteria may be specified in codes, standards, or customer requirements.
• Examples of acceptance criteria include maximum allowable defect size, minimum detectable defect size, and maximum allowable defect density.

11. what Do you know about DAC?
Answer :- DAC stands for Digital Acquisition System, used in NDT to convert analog signals to digital signals for analysis.

• DAC is used in NDT to convert analog signals to digital signals for analysis
• It is an important component of the inspection system
• DAC is used to improve the accuracy of flaw detection and sizing
• It can be used in ultrasonic, eddy current, and other NDT methods
• DAC curves are used to calibrate the inspection system.

12. What are the different types of hardness tests carried out?
Answer: -

• Brinell Hardness Test.
• Rockwell Hardness Test.
• Vicker Hardness Test.