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Final Exam (NE361)
Non Destructive Testing Overview - Fall 2015
Q-1 Read each question carefully and select the one best answer.
1. Which of the following statements accurately describes the capabilities of liquid penetrant testing?
(a) Liquid penetrant testing is useful for locating discontinuities which are open to the surface in non-porous materials
(b) Liquid penetrant testing is useful for locating discontinuities in porous materials
(c) Liquid penetrant testing is useful for locating subsurface discontinuities in a test piece
(d) Liquid penetrant testing is useful for locating discontinuities inside a test piece
2. Liquid penetrant testing is based on the principle of:
(a) sound properties
(b) Capillary action
(c) electromagnetic waves
(d) Magnetic field
3. The colour of fluorescent penetrant under the presence of a UV light is:
(a) Blue green
(b) Yellow Braun
(c) Yellow green
(d) yellow
4. Which penetrant process is best suited to high production rates of many small parts?
(a) Solvent removable
(b) Post emulsifiable
(c) Fluorescent
(d) Water washable
5. Which penetrant process is the most sensitive to detect fine discontinuities?
(a) Solvent removable
(b) Post emulsifiable fluorescent
(c) Water washable
(d) Water washable fluorescent
6. The typical temperature ranges for conducting a liquid penetrant test is:
(a) 60 to 100ºC
(b) 20 to 50ºC
(c) 10 to 60ºF
(d) 10 to 20ºK
7. Which of the following discontinuity types could typically be found with a liquid penetrant test?
(a) surface cracks
(b) Internal slag in a casting
(c) Sensitization in austenitic stainless steel
(d) Internal porosity in a weld
8. Which of the following methods is not recommended for pre-cleaning prior to a liquid penetrant test:
(a) Steam cleaning, etching, rust and paint removal
(b) Blasting, grinding, filing, honing, machining
(c) Solvent wipe, vapor degreasing, ultrasonic bath cleaning
(d) None of the above
9. The advantages of using a visible solvent removable penetrant versus a post emulsified fluorescent penetrant is:
(a) UV light is needed
(b) The technique is well suitable for site tests or spot checks
(c) water or emulsifiers are needed
(d) None o the above
10. The purpose of using a developer in liquid pentrant testing is:
(a) to help in cleaning the part after test
(b) Prevent the part from corroding after the liquid penetrant test
(c) To ensure that the part has been correctly heat treated
(d) Assists in reverse capillary action due to absorption ability of developers
11. Magnetic particles testing is most likely to find subsurface discontinuities in:
(a) Hardened steels with low permeability
(b) Soft steels with low permeability
(c) Hardened steels with high permeability
(d) Soft steels with high permeability
12. Which of the following is an advantage of magnetic particles testing?
(a) Fast and simple to perform
(b) Can detect discontinuities filled with foreign material
(c) Works well through a thin coat of paint
(d) all of the above
13. Which of the following does not represent a limitation of magnetic particle testing?
(a) The ability to detect discontinuities filled with foreign material
(b) The directionality of the magnetic field
(c) The need for demagnetization
(d) The type of materials which may be effectively tested
14. The most effective NDT method for locating surface cracks in ferromagnetic materials is:
(a) Magnetic particle testing
(b) Radiographic testing
(c) Ultrasonic testing
(d) Liquid penetrant testing
15. The most effective NDT method for locating surface cracks in non ferromagnetic materials is:
(a) Magnetic particle testing
(b) Radiographic testing
(c) Ultrasonic testing
(d) Liquid penetrant testing
16. A discontinuity which is produced during solidification of the molten metal is called:
(a) Service
(b) Processing
(c) Inherent
(d) None of the above
17. Pipe would be classified as what type of discontinuity?
(a) Inherent
(b) Processing
(c) Service
(d) None of the above
18. A seam would be classified as what type of discontinuity?
(a) Service
(b) Processing
(c) Inherent
(d) None of the above
19. A lamination in steel plate would be classified as what type of discontinuity?
(a) Service
(b) Processing
(c) Inherent
(d) None of the above
20. An internal rupture caused by working steel at improper temperatures is called a:
(a) Lap
(b) Cold shut
(c) Forging burst
(d) Slag inclusion
21. Cracks which are caused by alternating stresses above a critical level are called:
(a) Fatigue cracks
(b) Cycling cracks
(c) Critical cracks
(d) Stress corrosion cracks
22. Cracks which are caused by a combination of tensile stress and corrosion are called:
(a) Critical cracks
(b) Cycling cracks
(c) Stress corrosion cracks
(d) Fatigue cracks
23. Which of the following are ferromagnetic materials?
(a) Aluminum, iron, copper
(b) Iron, cobalt, nickel
(c) Copper, aluminum, silver
(d) Iron, copper, nickel
24. The reverse magnetising force necessary to remove a residual magnetic field from a test piece after it has been magnetically saturated is called:
(a) Hysteresis
(b) Coercive force
(c) Demagnetising flux
(d) Reverse saturation
25. Magnetic lines of force enter and leave a magnet at:
(a) Poles
(b) L/D ratios of greater than 4 to 1
(c) Flux concentration points
(d) Saturation
26. The ease with which a magnetic field can be established in a test piece is called:
(a) Reluctance
(b) Retentivity
(c) Permeability
(d) Electromagnetism
27. A magnetic field which is contained completely within the test piece is called a:
(a) Confined field
(b) Longitudinal field
(c) Circular field
(d) Saturated field
28. Which of the following produces a circular field?
(a) Head shot
(b) Coil
(c) Yoke
(d) All of the above
29. A leakage field is strongest when a discontinuity interrupts the magnetic flux lines at an angle of:
(a) Zero degrees
(b) 90 degrees
(c) 45degrees
(d) 180 degrees
30. The best method of inducing a circular field in a tube is by a:
(a) Central conductor
(b) Head shot
(c) Prod technique
(d) Coil
31. Which of the following types of intensifying screens are not used in industrial radiography?
(a) Lead
(b) Fluorescent
(c) Silver halide
(d) All of the above
32. Betatrons are used to produce X rays in what range?
(a) Several MeV
(b) 0-50 keV
(c) 50-500 keV
(d) 500-1000 keV
33. Which of the following is an isotope not artificially produced for industrial use:
(a) Ir-192
(b) Ra-226
(c) Co-60
(d) All of the above
34. One half value layer of lead for Iridium-192 is approximately:
(a) 12 mm
(b) 4 mm
(c) 2 mm
(d) 25 mm
35. The film processing step in which the undeveloped silver bromide is removed from the film emulsion is called:
(a) Development
(b) Stop bath
(c) Fixing
(d) Rinsing
36. A radiation producing device which emits radiation of one or a few discreet wavelengths is:
(a) An X ray machine
(b) A linear accelerator
(c) A gamma ray source
(d) A betatron
37. The intensifying action of lead screens is caused by:
(a) Secondary X ray emission
(b) Secondary gamma ray emissions
(c) Fluorescence of lead screens
(d) Electron emission
38. Most of the energy applied to an X ray tube is converted into:
(a) X rays
(b) Heat
(c) Light
(d) Ultraviolet radiation
39. Which of the following types of radiation is particulate?
(a) Alpha
(b) Gamma ray
(c) x ray
(d) None of the above
40. Most scattered radiation which adversely affects the radiographic image quality originates:
(a) From floors and walls adjacent to the test piece
(b) From other nearby objects
(c) From the test piece itself
(d) From the lead intensifying screens
41. An effect of scattered radiation is to:
(a) Decrease required exposure time
(b) Diminish contrast, detail and clarity of radiographic image
(c) Decrease film density
(d) All of the above
42. The penetrating power of an X ray machine is indicated by:
(a) Milliamperage
(b) Tube voltage
(c) Filament current
(d) Anode current
43. The main advantage of having small focal spot on an X ray tube is:
(a) Heat is conducted away more efficiently than with a large focal spot
(b) A smaller focal spot is unlikely to be damaged from the required tube currents
(c) Longer tube life
(d) A smaller focal spot allows sharper radiographic images than does a larger focal spot
44. Cobalt-60 is produced by:
(a) Fission of Uranium-235
(b) Neutron capture by Cobalt-59
(c) Radioactive decay
(d) None of the above
45. For a particular isotope, gamma radiation intensity is determined by:
(a) Source strength in curies
(b) Energy level of gamma rays in source
(c) Type of isotope used
(d) None of the above
46. Which of the following statements should be true to achieve the highest level of radiographic sharpness (definition)?
(a) The focal spot should be as small as practicable
(b) The focal spot to test piece distance should be as large as practicable
(c) The film to test piece distance should be as small as practicable
(d) All of the above
47. Thicker materials would normally be inspected using:
(a) Lower kV X rays
(b) Higher mA X rays
(c) Higher kV X rays
(d) Lower mA X rays
48. Another name for a penetrameter is:
(a) Radiographic shim
(b) Image quality indicator
(c) Density standard
(d) Acceptance standard
49. The difference in densities seen on a radiograph due to section changes in an item is:
(a) Film contrast
(b) Radiographic contrast
(c) Subject contrast
(d) Radiographic sensitivity
50. Which type of film would exhibit the coarsest grain?
(a) Slow
(b) Medium
(c) Fast
(d) No difference in the grain sizes
51. A straight, dark line in the centre of the film of a weld cap would probably be:
(a) Porosity
(b) Undercut
(c) Tungsten inclusions
(d) A linear crack
52. The normal range of steel that is radiographed using Ir-192 is:
(a) 5 mm–20 mm
(b) 7 mm – 75 mm
(c) 0.5 mm – 5 mm
(d) 75 mm – 150 mm
53. The focal spot size of an X ray machine must be known in order to determine:
(a) The geometric unsharpness
(b) Kilovoltage peak output
(c) Required mA setting
(d) Exposure time
54. The amount of radioactivity which corresponds to 3.7 × 1010 disintegrations per second is called:
(a) 0.01 gray (1 rad)
(b) 1 Farad
(c) 37 GBq (1 curie)
(d) 10 mSv (1 roentgen)
55. Which of the following isotopes are commonly used for radiographic purposes?
(a) Iridium-192
(b) Osmium-188
(c) Cobalt-87
(d) Rubidium
Q-2. Show the liquid penetrant testing steps using method C (solvent removable)?
Key words may use : Penetrant, non aquous developer, solvent wip inspect, reject, accept, rework, scrap, clean, dry reject ,clean ,drain & scrap.
Q-III Radiographic film consists of :
Q-IV Show how to radiograph a pipeline weld
Q-V A weld detected by radiography as shown below:
- Wide Gray areas represent base metal (false /true)
- White area represents weld bead (false /true)
- Gray spots on the white areas represent discontinuity (false /true)
- Discontinuities (Defect ) can interpret as Slag inclusions (false /true)
Q-VI Describe the given sketch using the following list
Q-VII The amount of radiation that is absorbed depends on:
- Density of material
- Thickness of material
- Both (a) & (b)
- Non of them
Q-VIII The sensitivity of a radiograph is a measure of its image quality. Sensitivity can be determined through the use of a :
- Penetrameter or image quality indicator (IQI).
- Density
- Lead letter
- Ruler
Q-IX What are the difference between figure (a) and (b)?
Fig. (a) Fig. (b)
Q-X Consider figure (a) and figure (b) to answer the below questions by answering with true or false :
- Figure a film –object distance is less ,while in Figure b is large (----------)
- Figure a discontinuity image is seen small size , Figure b is enlarged (----------)
- In figure b.,the image of the weld as "seen" by the radiation and any discontinuities the weld may contain will expand until they reach the film. (----------)
- Film –object distance when it increases, the result will be loss of definition and the discontinuities may not even be discernable(----------)
Q-XI Will the radiation detect the separation between the two plates as it did in below Fig.?
Q-XII Two plates have been welded together with the GMAW process and a 10 mm length of sidewall lack of fusion has occurred. Which position is preferable for the Ir192 source, position A or position B?
- A
- B
- A or B
- Nor A or B
Q-XIII Specimen below showed indication after applying liquid penetrant testing , interpret the results?
Q-XIV Rearrange the following steps to be a typical setup for a water wash LPI line :
Wash Station, Cleaning station ,
Penetrant application , Rinse Tank ,
Inspection, Drain rack )
Step 1 :
Step 2 :
Step 3 :
Step 4 :
Step 5 :
Step 6 :
Q-XV The bolt shown below has been circularly magnetized. Which of the four linear indications shown (A, B, C and D) will be detected?
- All c) A, B and c
- B only d) A, B and D
Q_XVI For prod magnetization ASTM E709 , per 25 mm (1 in.) of prod spacing for material 19 mm (3/4 in.) and over in thickness, recommends a magnetizing current of :
- 90
- 90 to 110
- 100 to 120
- 90 to 100
Q-XVII Suppose the shaft is 100 cm long and 10 cm in diameter and is to be magnetized in a coil having 5 turns. Calculate the amperage to be applied to magnetic particles test according the ASTM E 709 formulas:
(a) For parts with a substantial length/diameter ratio such as the shaft, the formula is:
It = 35,000 / [ (L/D) + 2 ]
(b) For parts with an L/D ratio less than 4 but not less than 2 the formula is:
It = 45,000 / (L/D)
where: t = number of turns in the coil, I = current in amperes
L = length of part, D = diameter of part
It = amp turns the numbers 35000 and 45000 are empirically derived constants
Q-XVIII A standard calibration test for the yoke must be able to lift (on AC) :
- 2.5 kg
- 3 Kg
- 18 kg
- No of the above
Q-XIX When Concentration of magnetic particles in a liquid vehicle is measured using a 100 mL pear shaped tube. The recommended concentration is:
- For fluorescent particles the generally recommended concentration is from 0.1 to 0.4 mL per 100 mL. For non-fluorescent particles it is from 1.2 to 2.4 mL per 100 mL
- For fluorescent particles the generally recommended concentration is from 0.2 to 0.6 mL per 100 mL. For non-fluorescent particles it is from 1.5 to 2.6 mL per 100 mL
- For fluorescent particles the generally recommended concentration is from 0.1 to 0.3 mL per 100 mL. For non-fluorescent particles it is from 1.2 to 2.4 mL per 100 mL
- For fluorescent particles the generally recommended concentration is from 0.1 to 0.4 mL per 100 mL. For non-fluorescent particles it is from 1 to 4 mL per 100 mL
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