Railway Engineering Questions and Answers – Rail Flaw Detection


This set of Railway Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Rail Flaw Detection”.

1. How can rail flaws be detected?
a) By visual examination
b) By rail flaw detection equipment
c) By visual examination or equipment
d) By using chemicals
View Answer

Answer: c
Explanation: Flaws are the defects which can lead to fracture of rails. Thus their detection is important and can be done visually or with the help of equipment.

2. What is another name of Ultrasonic rail flaw detection technique?
a) Non-destructive method of testing
b) Destructive method of testing
c) Method of visual examination
d) Metallurgical flaw detection
View Answer

Answer: a
Explanation: The rails/joints are not opened in USFD method. This method is also called Non-destructive method of testing of rails.

3. What is the minimum frequency of ultrasonic waves?
a) 20,000 cycles per second
b) 25,000 cycles per second
c) 31,400 cycles per second
d) 25,000 cycles per minute
View Answer

Answer: a
Explanation: Ultrasonic waves are the waves having frequency more than 20,000 cycles per second. They follow principles of reflection, refraction and transmission.

4. How defects are identified using ultrasonic waves?
a) They pass through the flaw
b) They reflect back from the flaw
c) They give sound when encountered a flaw
d) They release heat at location of flaw
View Answer

Answer: b
Explanation: When the ultrasonic waves detect a flaw they have a property of reflecting back. This is used for detection of defects in the rail.

5. Crystal transducers are used for ________
a) Production of ultrasonic frequency
b) Measuring the cracks in rails
c) Shaping the wheels
d) Production of sound
View Answer

Answer: a
Explanation: Crystal transducers are made of Barium or Quartz and are the simplest method used for production of ultrasonic frequency. This is then used for detection of flaws.

6. Which probe is suitable for detecting horizontal and inclined flaws?
a) Normal probe
b) Angle probe
c) Semi normal probe
d) Crystal probe
View Answer

Answer: a
Explanation: Normal probes transmit the ultrasonic waves in downward direction. They can be used to detect horizontal, inclined flaws and bolt hole cracks.

7. Which of the following techniques is used by Indian railways for ultrasonic testing?
a) Transmission
b) Resonance
c) Frequency modulation
d) Acoustic range
View Answer

Answer: c
Explanation: Different techniques are adopted depending on the type of equipment involved. Indian railway uses pulse echo as well as frequency modulation methods.

8. How is the echo arising due to fault determined using pulse echo system?
a) By its relative position
b) By its amplitude
c) By its range
d) By its relative position and amplitude
View Answer

Answer: d
Explanation: When ultrasonic waves are sent they may have more than one reflection. But the one corresponding to a fault is easily recognized by its relative position and amplitude.

9. What does IMR stand for in the classification of Rail flaws?
a) Immediate removal
b) Intentional removal
c) Intermediate repetition
d) Incremental repetition
View Answer

Answer: a
Explanation: IMR stands for immediate removal. These flaws are serious in nature and can lead to accidents. Rails having such flaws should be replaced quickly.

10. What type of defect is OBS defect?
a) Not so serious
b) Immediate removal
c) Warning of early removal
d) Safe rail
View Answer

Answer: a
Explanation: OBS stands for observe. These defects are not so serious and rail has to be kept under observation.

11. An OBS(E) designation represents a defect ______
a) On major bridges
b) Within the fish plate
c) Anywhere on the track
d) At joints
View Answer

Answer: b
Explanation: A defect around 100m from approach of a bridge is designated as OBS(B). OBS(E) stands for defect within fish plate zone.

12. Which of the following can be used for testing of long railway tracks?
a) German rail testing car
b) Manual methods
c) Rail testing trolley
d) Mechanical gauges
View Answer

Answer: a
Explanation: Rail testing trolley can test only 2-3 km of rail in a day. Thus German rail testing car can be used which tests around 200km per day efficiently.

13. What is the frequency prescribed for the need based concept of the ultrasonic testing?
a) 15 GMT
b) 8 GMT
c) 10 GMT
d) 6 GMT
View Answer

Answer: b
Explanation: The inspection of rails can be done after the passage of every 8GMT of load. Thus, frequency for need based ultrasonic testing is 8GMT.

14. In frequency modulation technique cracks below bolt holes are not detected.
a) True
b) False
View Answer

Answer: a
Explanation: Cracks completely below the bolt holes remain undetected by the frequency modulation technique. This is because of the interruptions caused by the hole.

15. What does SPURT stand for in SPURT car procured by the Indian railways?
a) Self-propelled Ultrasonic Rail Testing
b) Self-programmed Ultrasonic Rail Testing
c) Satellite Proposed Universal Rail Testing
d) Series Processed Unit for Rail Testing
View Answer

Answer: a
Explanation: SPURT stands for Self-propelled Ultrasonic Rail Testing car. It is used for detecting, analysing, recording the internal defects in the rails.

Sanfoundry Global Education & Learning Series – Railway Engineering.

To practice all areas of Railway Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.

Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & technical discussions at Telegram SanfoundryClasses.