1. Liquid penetrant testing is based on the principle of:
(a) Polarized sound waves in a liquid
(b) Magnetic domains
(c) Absorption of X rays
(d) Capillary action
2. When a small diameter tube is placed in a glass of water, water rises in the tube to a level above the adjacent surface. This is called:
(a) Viscosity
(b) Capillary action
(c) Surface tension
(d) Barometric testing
3. How is the size of a liquid penetrant indication usually related to the discontinuity it represents:
(a) Larger than
(b) Smaller than
(c) Equal to
(d) Not related to
4. A penetrant that is self-emulsifying is called:
(a) Solvent removable
(b) Water washable
(c) Post-emulsified
(d) Dual sensitivity method
5. A penetrant process which employs an emulsifier as a separate step in the penetrant removal process is called:
6. A penetrant process in which excess penetrant is removed with an organic solvent is called:
(d) Dual method
7. Which of the following statements accurately describes the capabilities of liquid penetrant testing?
(a) Liquid penetrant testing is useful for locating subsurface discontinuities in a test piece
(b) Liquid penetrant testing is useful for locating discontinuities in porous materials
(c) Liquid penetrant testing is useful for locating discontinuities which are open to the surface in non-porous materials
(d) none of the above
8. Which of the following discontinuity types could typically be found with a liquid penetrant test?
(a) Internal slag in a weld
(b) Internal slag in a casting
(c) Sensitization in austenitic stainless steel
(d) Fatigue cracks
9. Which of the following chemical elements are normally held to a minimum in liquid penetrant materials, when testing stainless steel and titanium?
(a) Hydrogen
(b) Chlorine
(c) Carbon
(d) Oil
10. Which of the following chemical elements are normally held to a minimum in liquid penetrant materials when testing nickel based alloys?
(a) Sulphur
(b) Oxygen
(d) Nitrogen
11. Which of the following is the most desirable method of pre-cleaning a test piece prior to penetrant testing?
(a) Sand blasting
(b) Vapour degreasing
(c) Emery cloth
(d) Wire brushing
12. Which of the following pre-cleaning processes is not recommended?
(a) Detergent cleaning
(c) Shot blasting
(d) Ultrasonic cleaning
13. A wire brush should be used for pre-cleaning:
(a) When grease and oil must be removed
(b) Only as a last resort
(c) When rust is to be removed
(d) When grinding burrs must be removed
14. A hydrometer is used to measure:
(a) Penetrant viscosity
(b) Specific gravity of water based wet developers
(c) Penetrant specific gravity
(d) Cleaner specific gravity
15. Visible, solvent removable penetrants are most advantageous for:
(a) Inspecting parts with rough surfaces
(b) Inspecting batches of small parts
(c) Inspecting parts at remote locations
(d) Inspecting parts with porous surfaces
16. For adequate test results, the black light used in fluorescent penetrant examination should provide what minimum black light intensity at the test surface?
(a) 100 foot candles per square centimetre
(b) 1000 microwatts per square centimetre
(c) 800 foot candles
(d) 35 microwatts per square centimetre
17. What minimum warm-up time is required for acceptable performance of a mercury Vapour arc black light?
(a) None
(b) 2 minutes
(c) 5 minutes
(d) 10 minutes
18. Which of the following penetrants contains an emulsifying agent?
(c) Post emulsifiable
(d) Fluorescent
19. Which of the following penetrants must be treated with an emulsifier prior to water removal?
20. What is the function of an emulsifier?
(a) To remove the excess penetrant
(b) To develop indications with a post emulsifiable penetrant system
(c) To assist penetration with a post emulsifiable penetrant system
(d) To make a post emulsifiable penetrant water washable
21. An oil based emulsifier is called:
(a) Hydrophilic
(b) Hydrophobic
(c) Lipophilic
(d) Fluoroscopic
22. A water based emulsifier is called:
23. Methylene chloride, isopropyl, alcohol, naptha and mineral spirits are examples of:
(a) Emulsifiers
(b) Developers
(c) Solvent removers
(d) None of the above
24. What type of solvent removers may be used with a solvent removable penetrant?
(a) Any organic solvent
(b) Only the cleaner recommended by the manufacturer of the penetrant
(c) Any alcohol based solvents
(d) Only chlorinated hydrocarbons
25. Which of the following is a prerequisite for a penetrant test?
(a) Developer must be applied in a thin, even coat
(b) Any surface coatings or soils must be completely removed
(c) All traces of penetrant materials should be removed after testing is complete
(d) The test object must be non-magnetic
26. Which of the following types of pre-cleaning processes may be used for liquid penetrant testing?
(a) Wire brushing only
(b) Detergent and water only
(c) Vapour degreasing only
(d) Any process that leaves the part clean and dry, does not harm the part and is compatible with the penetrant materials
27. What is the likely result of incomplete removal of all excess penetrant from the test piece surface?
(a) Formation of false indications
(b) Formation of relevant indications
(c) Exaggeration of the size of relevant indications
28. What is the preferred pre-cleaning process for removal of oil and grease :
(a) Steam cleaning with a added acid
(c) Steam cleaning
29. Which pre-cleaning method may be used with either a solvent or a detergent solution?
(a) Ultrasonic cleaning
(b) Steam cleaning
(c) Detergent wash
(d) Vapour degreasing
30. What is the danger associated with using a wire brush during pre-cleaning?
(a) Bristles from the wire brush may cause false indications
(b) Contaminants from the wire brush may cause delayed hydrogen cracking of high carbon steels
(c) The wire brush may not adequately remove organic soils
(d) The wire brush may close or smear metal over
31. What is the preferred method of removing paint prior to performing a penetrant testing?
(a) Sand blast
(b) Chemical removers
(c) Power wire brush
(d) Shot blast
32. What additional surface preparation or cleaning must be performed on a machined or ground aluminium casting prior to penetrant testing?
(a) Vapour degreasing
(b) Etching
(d) Nothing
33. Acceptable methods of penetrant application are:
(a) Spraying
(b) Dipping
(c) Brushing
(d) All of the above
34. The time period during which penetrant remains on the surface of the test piece is called:
(a) Dwell time
(b) Soaking time
(c) Fixing time
(d) Development time
35. Excess penetrant removal is a two step process with which of the following penetrant methods?
(a) Water washable
(b) Post emulsifiable
(c) Solvent removable
(d) Liquid oxygen applications
36. A developer aids penetrant bleed out because of:
(a) Adequate removal of the excess penetrant
(b) Providing a contrasting background for visible dye indications
(c) Capillary action
(d) Proper emulsifier action
37. In the solvent removable penetrant process, excess penetrant is removed with:
(a) A water spray
(b) A hydrophilic scrubber
(c) A solvent spray
(d) Clean, lint free towels slightly moistened with solvent
38. Water based wet developer is applied:
(a) Immediately before removal of excess penetrant
(b) Immediately after removal of excess penetrant
(c) After a drying period following removal of excess penetrant
(d) For maximum sensitivity results
39. Non-aqueous wet developer is applied:
(c) After the excess penetrant is removed and part surface is dried
40. Dry developer is applied:
(c) After drying of the part
41. Typical ranges of emulsifier dwell times are:
(a) 5 to 10 minutes
(b) 30 seconds to 1 minute
(c) 1 to 3 minutes
(d) 5 to 10 minutes
42. Actual emulsification times are determined by:
(a) Experiment, during technique qualification
(b) Manufacturer's recommendations
(c) Code requirements
43. The colour of fluorescent penetrant under the presence of a UV light is:
(a) Yellow-green
(b) Red
(c) Blue
(d) Green
44. What action is necessary if the penetrant is inadvertently allowed to dry on the test piece?
(a) Repeat the test, beginning with the pre-cleaning operation
(b) Re-wet the penetrant, begin dwell time again and continue
(c) Clean the penetrant off the surface and develop normally
(d) Clean the penetrant off the surface, wait 5 minutes and develop normally
45. What maximum water rinse pressure is considered safe for removal of excess penetrant in the water washable penetrant process?
(a) As low a pressure as possible, 50 PSI maximum
(b) to 200 PSI
(c) PSI maximum
(d) to 500 PSI
46. During the water rinse step of the water washable penetrant process, what is the desired angle of the spray to the surface?
(a) Normal
(b) 30 degrees
(c) 45 degrees
(d) 75 degrees
47. Which type of emulsifier is designed to be used as a ‘scrubber’?
48. Post cleaning is especially important when:
(a) Post emulsified penetrants are used
(b) Phosphate containing detergents are used
(c) Chlorinated hydrocarbons are used
(d) The test object will be used in a liquid oxygen environment
49. When using a hydrophilic emulsifier, the amount of penetrant removed is most affected by:
(a) Solution strength and time of spray
(b) Penetrant dwell time
(c) Emulsifier dwell time
(d) Adequacy of pre-clean
50. If a mercury vapour arc black light is inadvertently turned off, how soon may it be restarted?
(a) Immediately
(b) 5 minutes
(c) 10 minutes
(d) 15 minutes
