ArulmiguMeenakshi Amman College of Engineering
Vadamavandal-604410.
Impotant questions and answers
OML351-INTRODUCTION TO NON-DESTRUCTIVE TESTING
Prepared by
V.Umapathy,
Prof. /Mech.
S.No. Questions and answers
Unit-I
INTRODUCTION TO NDT & VISUAL TESTING
2 – marks question and answers
1. Write the concepts of non-destructive testing.
Non-destructive testing (NDT) is a set of techniques that evaluate the quality of a material, component, or system
without causing damage. NDT is used in many industries, including aerospace, oil and gas, nuclear, and
manufacturing.
NDT is important because it:
1 .Prevents costly failures: NDT can help prevent costly failures and accidents.
2. Saves time and money: NDT is often preferred to destructive tests because it saves time and money.
3. Maintains safety and reliability: NDT is key to maintaining safety, reliability, and efficiency in industries.
Some types of NDT include:
4. Ultrasonic testing: Uses high-frequency sound waves to detect internal faults
5. Radiographic testing: Uses X-rays or gamma rays to capture images of a structure's interior
6. Magnetic particle testing: Uses magnetic fields to find discontinuities at or near the surface of ferromagnetic
materials
, 7. Thermal/infrared testing: Uses thermal wave imaging to find disbonds in aluminum structures, corrosion
behind painted surfaces, and more
NDT is regulated by codes and standards according to the type of industry, country, and other criteria.
2. List relative merits and limitations of non-destructive testing.
Destructive testing has several advantages and disadvantages, including:
Advantages
1.Definitive results: Destructive testing can provide accurate information about a material's properties, such as its
strength, hardness, and durability.
2. Performance limits: Destructive testing can help determine a material's performance limits and failure
modes.
3. Quality control: Destructive testing can help improve the quality and safety of products.
4. Easier to interpret: Destructive testing is often easier to interpret than non-destructive testing.
Disadvantages
1. Destroys the material: The material or product being tested is destroyed in the process.
2. Expensive: Destructive testing can be expensive.
3. Time-consuming: Destructive testing can be time-consuming.
4. 4.Only provides information about the sample: Destructive testing only provides information about the sample
being tested, not the entire batch.
5. Unpredictable scope: The extent of failures and their effects can be unpredictable.
6. Incomplete testing: Destructive testing may not identify all vulnerabilities.
7. Costly fixes: Addressing issues found through destructive testing can be expensive.
Destructive testing is used in various industries, including automotive, to evaluate the quality and strength of
components.
3 What is the difference between NDT and mechanical testing?
, Mechanical testing, which is also known as destructive testing, is accomplished by forcing a part to fail by the
application of various load factors. In contrast, non-destructive testing does not affect the part's future usefulness
and leaves the part and its component materials in tact.
4 What is the principle of visual testing?
Visual testing includes all non-destructive testing techniques that use electromagnetic radiation in the field of
visible light, i.e. in the band of wavelengths between 400 and 700 nm approximately the geometry and power of
which can highlight the defects sought.
5. What are the materials used in visual testing?
Visual testing is used to find surface discontinuities, which is done with the naked eye. Some equipment you might
use with visual testing includes mirrors, magnifying glasses and boroscopes. If the component you're working with
can in fact be viewed, that is the first step in the NDT examination.
6. What are the environmental factors of visual impairment?
Some environmental factors can damage your eyes include: Pollution: Being exposed to air pollution constantly
can cause blurred vision, watery eyes, ocular burns, or dry eye. UV rays: Excessive exposure to UV radiation can
damage the retina or cornea of the eye.
7. What is visual perception?
Visual Perception is the ability to interpret, understand, and define incoming visual information. Form Constancy is
the ability to identify objects despite their variation of size, color, shape, position, or texture. Figure ground
Perception is the ability to distinguish foreground from background.
8. What is the borescope method of testing?
The borescope inspection (also known as a "remote visual inspection" or RVI) involves using a flexible or rigid
optical device that allow the inspector to examine areas that are otherwise difficult to access.
9. What equipment is used in visual inspection?
Non Destructive Testing (NDT) is concerned with all methods of detecting flaws in materials and can be performed
optically using non-specialised visual inspection equipment such as Microscopes, Endoscopes or Borescopes
10. What are the different types of light sources used in visual inspection?
The best lighting for visual inspection is most often LED, as it provides a bright light while remaining energy-
efficient. LED visual inspection lighting for microscopes also has better longevity compared to traditional halogen
bulbs meaning fewer lamp replacements over its lifetime.
, 13 and 15 marks question and answers
11. Describe the Non –Distractive Testing Methods in detail for material characterization.
Non-destructive testing (NDT) methods for material characterization include:
1. Radiographic testing
Uses X-rays or gamma rays to create an image of a material's internal structure, which can be analyzed for
Vadamavandal-604410.
Impotant questions and answers
OML351-INTRODUCTION TO NON-DESTRUCTIVE TESTING
Prepared by
V.Umapathy,
Prof. /Mech.
S.No. Questions and answers
Unit-I
INTRODUCTION TO NDT & VISUAL TESTING
2 – marks question and answers
1. Write the concepts of non-destructive testing.
Non-destructive testing (NDT) is a set of techniques that evaluate the quality of a material, component, or system
without causing damage. NDT is used in many industries, including aerospace, oil and gas, nuclear, and
manufacturing.
NDT is important because it:
1 .Prevents costly failures: NDT can help prevent costly failures and accidents.
2. Saves time and money: NDT is often preferred to destructive tests because it saves time and money.
3. Maintains safety and reliability: NDT is key to maintaining safety, reliability, and efficiency in industries.
Some types of NDT include:
4. Ultrasonic testing: Uses high-frequency sound waves to detect internal faults
5. Radiographic testing: Uses X-rays or gamma rays to capture images of a structure's interior
6. Magnetic particle testing: Uses magnetic fields to find discontinuities at or near the surface of ferromagnetic
materials
, 7. Thermal/infrared testing: Uses thermal wave imaging to find disbonds in aluminum structures, corrosion
behind painted surfaces, and more
NDT is regulated by codes and standards according to the type of industry, country, and other criteria.
2. List relative merits and limitations of non-destructive testing.
Destructive testing has several advantages and disadvantages, including:
Advantages
1.Definitive results: Destructive testing can provide accurate information about a material's properties, such as its
strength, hardness, and durability.
2. Performance limits: Destructive testing can help determine a material's performance limits and failure
modes.
3. Quality control: Destructive testing can help improve the quality and safety of products.
4. Easier to interpret: Destructive testing is often easier to interpret than non-destructive testing.
Disadvantages
1. Destroys the material: The material or product being tested is destroyed in the process.
2. Expensive: Destructive testing can be expensive.
3. Time-consuming: Destructive testing can be time-consuming.
4. 4.Only provides information about the sample: Destructive testing only provides information about the sample
being tested, not the entire batch.
5. Unpredictable scope: The extent of failures and their effects can be unpredictable.
6. Incomplete testing: Destructive testing may not identify all vulnerabilities.
7. Costly fixes: Addressing issues found through destructive testing can be expensive.
Destructive testing is used in various industries, including automotive, to evaluate the quality and strength of
components.
3 What is the difference between NDT and mechanical testing?
, Mechanical testing, which is also known as destructive testing, is accomplished by forcing a part to fail by the
application of various load factors. In contrast, non-destructive testing does not affect the part's future usefulness
and leaves the part and its component materials in tact.
4 What is the principle of visual testing?
Visual testing includes all non-destructive testing techniques that use electromagnetic radiation in the field of
visible light, i.e. in the band of wavelengths between 400 and 700 nm approximately the geometry and power of
which can highlight the defects sought.
5. What are the materials used in visual testing?
Visual testing is used to find surface discontinuities, which is done with the naked eye. Some equipment you might
use with visual testing includes mirrors, magnifying glasses and boroscopes. If the component you're working with
can in fact be viewed, that is the first step in the NDT examination.
6. What are the environmental factors of visual impairment?
Some environmental factors can damage your eyes include: Pollution: Being exposed to air pollution constantly
can cause blurred vision, watery eyes, ocular burns, or dry eye. UV rays: Excessive exposure to UV radiation can
damage the retina or cornea of the eye.
7. What is visual perception?
Visual Perception is the ability to interpret, understand, and define incoming visual information. Form Constancy is
the ability to identify objects despite their variation of size, color, shape, position, or texture. Figure ground
Perception is the ability to distinguish foreground from background.
8. What is the borescope method of testing?
The borescope inspection (also known as a "remote visual inspection" or RVI) involves using a flexible or rigid
optical device that allow the inspector to examine areas that are otherwise difficult to access.
9. What equipment is used in visual inspection?
Non Destructive Testing (NDT) is concerned with all methods of detecting flaws in materials and can be performed
optically using non-specialised visual inspection equipment such as Microscopes, Endoscopes or Borescopes
10. What are the different types of light sources used in visual inspection?
The best lighting for visual inspection is most often LED, as it provides a bright light while remaining energy-
efficient. LED visual inspection lighting for microscopes also has better longevity compared to traditional halogen
bulbs meaning fewer lamp replacements over its lifetime.
, 13 and 15 marks question and answers
11. Describe the Non –Distractive Testing Methods in detail for material characterization.
Non-destructive testing (NDT) methods for material characterization include:
1. Radiographic testing
Uses X-rays or gamma rays to create an image of a material's internal structure, which can be analyzed for
