McqMate
Chapters
| 1. |
Which of the following is not a property of magnetic lines of force? |
| A. | They form closed loops which do not cross |
| B. | The density increases with distance from the poles of a permanent magnet |
| C. | Hey are considered to have direction |
| D. | They seek paths of least magnetic resistance or least reluctance |
| Answer» B. The density increases with distance from the poles of a permanent magnet | |
| 2. |
Surrounding an electromagnet, the magnetic field is strongest: |
| A. | Immediately after the current ceases to flow |
| B. | While the magnetizing current ceases to flow |
| C. | At the time the magnetic particles are applied to the part |
| D. | Just prior to current reversal |
| Answer» D. Just prior to current reversal | |
| 3. |
The value of permeability is: |
| A. | A fixed value depending upon the type of material |
| B. | Between 1 and 100 for all ferromagnetic materials |
| C. | Between 0 and 10 for all ferromagnetic materials |
| D. | Dependent upon the amount of magnetizing force necessary to overcome |
| Answer» A. A fixed value depending upon the type of material | |
| 4. |
The flux density of the magnetism induced by a coil is affected by: |
| A. | The coil size |
| B. | The current in the coil |
| C. | The number of turns in the coil |
| D. | All of the above |
| Answer» D. All of the above | |
| 5. |
How many turns of a coil will be needed to establish a longitudinal field in a steel shaft that is 22.86 cm (9 inches) long and 7.62 cm (3 inches) in diameter? 3000 amperes magnetizing current is available, it is desired to magnetize the part in accordance with the formula NI = 45,000/(L/D): |
| A. | 1 |
| B. | 3 |
| C. | 5 |
| D. | 7 |
| Answer» C. 5 | |
| 6. |
How many ampere-turns are required to magnetize a part that is 40.6 cm (16 inches) long and 5 cm (2 inches) in diameter? |
| A. | 9000 ampere-turns |
| B. | 5625 ampere-turns |
| C. | 2812 ampere-turns |
| D. | None of the above |
| Answer» B. 5625 ampere-turns | |
| 7. |
The lines of flux or force in a circularly magnetized ferromagnetic bar: |
| A. | Are aligned through the piece from the south to the north pole |
| B. | Are aligned through the piece from the north to the south pole |
| C. | Leave the south pole and enter the north pole |
| D. | Are contained within and around the part |
| Answer» D. Are contained within and around the part | |
| 8. |
In which magnetizing method is the current passed directly through the part, thereby setting up a magnetic field at right angles to the current flow? |
| A. | Longitudinal magnetization |
| B. | Coil magnetization |
| C. | Central conductor magnetization |
| D. | None of the above |
| Answer» D. None of the above | |
| 9. |
Which of the following is false concerning a magnetic field in and around a hollow conductor as compared to that of a solid conductor of the same outside diameter when both are of the same magnetic material, and when the applied current is the same? |
| A. | The field immediately outside the outer surface of the hollow conductor is greater |
| B. | The field gradient inside the hollow conductor is steeper |
| C. | The fields outside the conductors are the same |
| D. | The fields are the same at the centre |
| Answer» C. The fields outside the conductors are the same | |
| 10. |
The field in a section of ferromagnetic pipe being magnetized by means of a central conductor is strongest at the: |
| A. | Ends of the pipe |
| B. | Outer surface of the pipe |
| C. | Inner surface of the pipe |
| D. | The field is uniform at all places |
| Answer» C. Inner surface of the pipe | |
| 11. |
For a 7.6 cm (3 inches) diameter bar how much current is needed to magnetize the bar for the detection of longitudinal discontinuities: |
| A. | 5500 amperes |
| B. | 16500 amperes |
| C. | 1000 amperes |
| D. | 3000 amperes |
| Answer» D. 3000 amperes | |
| 12. |
For detection of longitudinal discontinuities a 7.6 cm (3 inches) diameter bar is magnetized in: |
| A. | The longitudinal direction |
| B. | The circular direction |
| C. | The clockwise direction |
| D. | None of the above directions |
| Answer» B. The circular direction | |
| 13. |
A bar that is 5 cm (2 inches) by 10 cm (4 inches) by 30.5 cm (12 inches) is being magnetized in the circular direction. About how many amperes are required using the perimeter approach? |
| A. | 2200 |
| B. | 4500 |
| C. | 3800 |
| D. | None of the above |
| Answer» C. 3800 | |
| 14. |
An advantage of AC is that: |
| A. | It is most readily available |
| B. | Equipment can be made lighter |
| C. | It leaves the part demagnetized |
| D. | All of the above |
| Answer» D. All of the above | |
| 15. |
When a magnetic field cuts across a crack: |
| A. | Electrons begin jumping back and forth across the crack |
| B. | The crack begins to heat up |
| C. | Magnetic poles form at the edges of the crack |
| D. | All of the above |
| Answer» C. Magnetic poles form at the edges of the crack | |
| 16. |
A disadvantage of AC current is that it: |
| A. | Cannot be used with dry powder |
| B. | Has poor penetrating power |
| C. | Can only provide low flux densities |
| D. | Cannot be used for residual magnetic particle testing |
| Answer» B. Has poor penetrating power | |
| 17. |
What causes a leakage field in a steel bar? |
| A. | A crack |
| B. | Reversal of the magnetic field |
| C. | Paint on the surface |
| D. | All of the above |
| Answer» A. A crack | |
| 18. |
An indication is a defect under which of the following conditions? |
| A. | If it is greater than 3.8 cm (1.5 inches) long |
| B. | If it exceeds the limits of a standard or specification |
| C. | If it is deep |
| D. | Under all of the above indications |
| Answer» B. If it exceeds the limits of a standard or specification | |
| 19. |
Paint will not affect the detection of a crack if: |
| A. | The paint is thick and the defect is subsurface |
| B. | The paint is thin and the crack is parallel to the direction of flux lines |
| C. | The crack is sharp and the paint is thin |
| D. | All of the above |
| Answer» C. The crack is sharp and the paint is thin | |
| 20. |
A magnetic particle indication is sharp and very fine; this suggests that the discontinuity is: |
| A. | Subsurface seam |
| B. | A shallow, tight surface crack |
| C. | Porosity |
| D. | A deep crack |
| Answer» B. A shallow, tight surface crack | |
| 21. |
Among the following, the best type of current for the detection of fatigue cracks is: |
| A. | Half-wave direct current |
| B. | Alternating current |
| C. | Direct current |
| D. | Half-wave alternating current |
| Answer» B. Alternating current | |
| 22. |
Continuous magnetization provides the most sensitivity because: |
| A. | The magnetic particles are present while the part is being magnetized |
| B. | The magnetic field is greatest while the magnetizing current is on |
| C. | All of the above |
| D. | Neither of the above |
| Answer» C. All of the above | |
| 23. |
The sensitivity of magnetic particle testing is greatest when the discontinuity is: |
| A. | Parallel to the direction of the magnetic flux lines |
| B. | Perpendicular to the flow of the magnetizing current |
| C. | Perpendicular to the direction of the magnetic flux |
| D. | Perpendicular to the line between prods |
| Answer» C. Perpendicular to the direction of the magnetic flux | |
| 24. |
To provide reliability and reproducibility in magnetic particle testing, written procedures should include: |
| A. | Location of the coil and current for each magnetization |
| B. | Requirements for ammeter calibration |
| C. | Type and concentration of the particles |
| D. | All of the above |
| Answer» D. All of the above | |
| 25. |
The magnetic particles are noticed to bunch in some fillet areas and stand on end on the edge of a part being magnetized. These observations indicate that the: |
| A. | Particle concentration is too low |
| B. | Flux density is excessive |
| C. | Flux density is too low |
| D. | Magnetizing current should be changed form AC to DC |
| Answer» B. Flux density is excessive | |
| 26. |
Flux density is a measure of the number of magnetic flux lines perpendicular to an area of cross-section. If a discontinuity is in the plane of the unit area, the strongest magnetic article indication will be formed when the discontinuity is: |
| A. | Inclined at 45º to the flux lines |
| B. | Parallel to the flux lines |
| C. | 90º to the flux lines |
| D. | 135º to the flux lines |
| Answer» C. 90º to the flux lines | |
| 27. |
Prods are being used to magnetize a weld area. When dry powder is dusted on the surface, it is observed that there is no mobility of the particles. What is the most probable reason for this observation? |
| A. | The magnetizing current is not high enough |
| B. | The flux density is too low |
| C. | DC is being used |
| D. | All of the above are possible reasons |
| Answer» D. All of the above are possible reasons | |
| 28. |
The current from portable high amperage units can be applied to the object using: |
| A. | Prods |
| B. | Cable coils |
| C. | Pre-wrapped coils |
| D. | All of the above |
| Answer» D. All of the above | |
| 29. |
How can parts be tested to determine if they have been adequately demagnetized? |
| A. | By bringing a suspended paper clip near the middle of the part |
| B. | By using a small horseshoe permanent magnet |
| C. | By using a small magnetometer held at a corner of the part |
| D. | By sprinkling some magnetic particles on the part |
| Answer» C. By using a small magnetometer held at a corner of the part | |
| 30. |
The statement ‘magnetic particle testing can be applied to plated and painted parts’. |
| A. | May be true depending upon the thickness of the coating |
| B. | May be true if flux densities are increased to compensate for the coating thickness |
| C. | Is true only for circular circumstances |
| D. | Both (a) and (b) |
| Answer» A. May be true depending upon the thickness of the coating | |
| 31. |
A group of indications, some sharp and some broad and fuzzy, were found on an area of a small forging. Demagnetization and re-inspection eliminated these indications. What was the probable cause? |
| A. | Forging lap |
| B. | Magnetic writing |
| C. | Change in permeability |
| D. | Subsurface variation |
| Answer» B. Magnetic writing | |
| 32. |
Magnetic particle testing is most likely to find subsurface discontinuities in: |
| A. | Soft steels with high permeability |
| B. | Soft steels with low permeability |
| C. | Hardened steels with low permeability |
| D. | Hardened steels with high permeability |
| Answer» A. Soft steels with high permeability | |
| 33. |
Which of the following is not an advantage of Magnetic Particle testing? |
| A. | Fast and simple to perform |
| B. | Can detect discontinuities filled with foreign material |
| C. | Most reliable for finding surface cracks in all types of material |
| D. | Works well through a thin coat of paint |
| Answer» C. Most reliable for finding surface cracks in all types of material | |
| 34. |
The most effective NDT method for locating surface cracks in ferromagnetic materials is: |
| A. | Ultrasonic testing |
| B. | Radiographic testing |
| C. | Magnetic particles testing |
| D. | Liquid penetrant testing |
| Answer» C. Magnetic particles testing | |
| 35. |
Opposition to establishment of a magnetic field in a test piece is called: |
| A. | Reluctance |
| B. | Retentivity |
| C. | Permeability |
| D. | Electromagnetism |
| Answer» A. Reluctance | |
| 36. |
A leakage field is strongest when a discontinuity interrupts the magnetic flux lines at an angle of: |
| A. | 0o |
| B. | 45o |
| C. | 90o |
| D. | 180o |
| Answer» C. 90o | |
| 37. |
A common rule of thumb to use for current required in circular magnetisation: |
| A. | 1000 amps/25 mm of diameter |
| B. | 1000 ampere-turns/25 mm of diameter |
| C. | 1000 amps/25 mm of prod spacing |
| D. | None of the above |
| Answer» A. 1000 amps/25 mm of diameter | |
| 38. |
The formula, NI = 45000/(L/D), is used to calculate the proper magnetising current for: |
| A. | Prod magnetisation |
| B. | A head shot |
| C. | A central conductor |
| D. | Coil magnetization |
| Answer» D. Coil magnetization | |
| 39. |
For direct contact magnetising methods, the magnetic field is oriented in what direction relative to the current direction? |
| A. | Parallel |
| B. | At 45o |
| C. | At 90o |
| D. | At 180o |
| Answer» C. At 90o | |
| 40. |
For direct contact magnetising methods, current should be flowing in what direction relative to expected discontinuities? |
| A. | Parallel |
| B. | At 45o |
| C. | At 90o |
| D. | At 180o |
| Answer» A. Parallel | |
| 41. |
What is the magnetic field strength at the surface of a 25 mm diameter bar as compared to that at the surface of a 50 mm diameter bar, each carrying 1000 amps of current? |
| A. | Twice |
| B. | One half |
| C. | One quarter |
| D. | Four times |
| Answer» A. Twice | |
| 42. |
Demagnetization, ASTM E709-95 recommends a coil of ampere-turns: |
| A. | 1000 to 3000 |
| B. | 3000 to 5000 |
| C. | 5000 to 10000 |
| D. | 10000 to 15000 |
| Answer» C. 5000 to 10000 | |
| 43. |
According to ASTM E709-95 when dry particles are used magnetic particle testing shall not be performed on the surface of parts whose temperature exceeds: |
| A. | 57ºC |
| B. | 79ºC |
| C. | 158ºC |
| D. | 136ºC |
| Answer» A. 57ºC | |
| 44. |
According to ASTM E709-95 in using prod technique, prod spacing shall not exceed: |
| A. | 50 mm |
| B. | 100 mm |
| C. | 150 mm |
| D. | 200 mm |
| Answer» D. 200 mm | |
| 45. |
According to ASTM E709-95, the UV intensity shall not be less than: |
| A. | 600 µW/cm2 |
| B. | 700 µW/cm2 |
| C. | 800 µW/cm2 |
| D. | 900 µW/cm2 |
| Answer» C. 800 µW/cm2 | |
| 46. |
According to ASTM E709-95 in using prod technique on a 50 mm thickness plate with a prod spacing of 101 mm (4 inches), current shall be selected in the following range: |
| A. | 300-450A |
| B. | 400-500 A |
| C. | 500-625A |
| D. | 550-700 A |
| Answer» A. 300-450A | |
| 47. |
According to ASMT E709-95 alternating current electromagnetic yokes should give a lifting force of at least: |
| A. | 1.5 kg |
| B. | 2.5 kg |
| C. | 3.5 kg |
| D. | 4.5 kg |
| Answer» D. 4.5 kg | |
| 48. |
According to ASTM E709-95 direct current electromagnetic yokes should have a lifting force of at least: |
| A. | 15 kg |
| B. | 16 kg |
| C. | 17 kg |
| D. | 18 kg |
| Answer» D. 18 kg | |
| 49. |
According to ASTM E709-95 the UV light shall be centred on (1 Å = 10-10m): |
| A. | 3000Å |
| B. | 3250 Å |
| C. | 3400Å |
| D. | 3650 Å |
| Answer» D. 3650 Å | |
| 50. |
According to ASTM E709-95 when fluorescent particles are used, the UV light intensity shall be above: |
| A. | 700 µW/cm2 |
| B. | 800 µW/cm2 |
| C. | 900 µW/cm2 |
| D. | 1000 µW/cm2 |
| Answer» D. 1000 µW/cm2 | |
| 51. |
According to ASTM E709-95 when fluorescent particles are used, the bulb shall be warmed up prior to use for at least: |
| A. | 1 min |
| B. | 2 min |
| C. | 3 min |
| D. | 4 min |
| Answer» D. 4 min | |
| 52. |
According to ASTM E709-95 with prod technique, the prods shall be tipped if the open circuit voltage is over: |
| A. | 10 V |
| B. | 15 V |
| C. | 20 V |
| D. | 25 V |
| Answer» D. 25 V | |
| 53. |
According to ASME Section VIII, a linear indication is defined as an indication in which the length is equal to or greater than the width by a factor of: |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 54. |
According to ASTM E709-95 the viscosity limit (measured in centi Stokes) of the wet medium (conditioned water) should not exceed: |
| A. | 1 cSt |
| B. | 3 cSt |
| C. | 6 cSt |
| D. | 4 cSt |
| Answer» C. 6 cSt | |
| 55. |
According to ASTM E709-95 when applying fluorescent magnetic particles technique, the operator shall be in darkness area at least......................prior to examination: |
| A. | 2 min |
| B. | 3 min |
| C. | 4 min |
| D. | 5 min |
| Answer» B. 3 min | |
| 56. |
According to ASTM E709-95 the alkalinity of conditioned water shall not exceed: |
| A. | 10.0 pH |
| B. | 10.5 pH |
| C. | 11.0 pH |
| D. | 11.5 pH |
| Answer» B. 10.5 pH | |
| 57. |
According to ASTM E709-95, with wet continuous magnetization technique, the duration of magnetization current is of the order of: |
| A. | 0.5 sec |
| B. | 1.0 sec |
| C. | 1.5 sec |
| D. | 2.0 sec |
| Answer» A. 0.5 sec | |
| 58. |
According to ASTM E709-95 in using prods having a spacing of 19 mm (3/4 inches) and above, the magnetizing current shall be: |
| A. | From 90 to 110 A/25 mm (1 inch) |
| B. | From 100 to 125 A/25 mm (1 inch) |
| C. | From 90 to 120 A/ 25 mm (1 inch) |
| D. | From 100 to 200 A/25 mm (1 inch) |
| Answer» B. From 100 to 125 A/25 mm (1 inch) | |
| 59. |
According to ASTM E709-95 powder shall be applied upon the part to be tested in such a manner that: |
| A. | A light uniform coating is formed |
| B. | In excess coating |
| C. | All of the above |
| D. | None of the above |
| Answer» A. A light uniform coating is formed | |
| 60. |
According to ASTM E709-95 before turning off current and examination, dry powder in excess shall be: |
| A. | Removed by a dry-air current |
| B. | Kept in place |
| C. | All of the above |
| D. | None of the above |
| Answer» D. None of the above | |
| 61. |
According to ASTM E709-95 demagnetization can be performed by: |
| A. | Decreasing alternating current |
| B. | Reversing direct current |
| C. | All of the above |
| D. | None of the above |
| Answer» C. All of the above | |
| 62. |
According to ASTM E709-95, Table 3., alternating current electromagnetic yokes must have a lifting force of at least: |
| A. | 3.0 kg (7 lb) |
| B. | 3.5 kg (8 lb) |
| C. | 4.0 kg (9 lb) |
| D. | 4.5 kg (10 lb) |
| Answer» D. 4.5 kg (10 lb) | |
| 63. |
According to ASTM E709-95, Table 3., direct current electromagnetic yokes must have a lifting force of at least: |
| A. | 15 kg (33 lb) |
| B. | 16 kg (36 lb) |
| C. | 17 kg (38 lb) |
| D. | 18 kg (40 lb) |
| Answer» D. 18 kg (40 lb) | |
| 64. |
According to API, the acceptable particle concentration of wet particle solution for fluorescent particles is: |
| A. | 0.1 to 0.4 mL by volume |
| B. | 0.1 to 0.5 mL by volume |
| C. | 0.1 to 0.6 mL by volume |
| D. | 0.1 to 0.7 mL by volume |
| Answer» A. 0.1 to 0.4 mL by volume | |
| 65. |
According to API, the particle concentration of wet particle solution must be checked: |
| A. | Prior to each shift |
| B. | Only after each shift |
| C. | Only each week |
| D. | Only each two weeks |
| Answer» A. Prior to each shift | |
| 66. |
According to ASTM E709-95 and API, the UV intensity measured at a minimum of 38 cm (15 inches) at least shall not be less than: |
| A. | 700 µW/cm2 |
| B. | 800 µW/cm2 |
| C. | 900 µW/cm2 |
| D. | 1000 µW/cm2 |
| Answer» D. 1000 µW/cm2 | |
| 67. |
According to ASTME 709-95 and API, in order to eliminate all contaminants, an appropriate cleaning shall be performed on all the surfaces to be examined and on a minimum of adjacent material: |
| A. | 25.4 mm (1 inch) |
| B. | 31.7 mm (5/4 inches) |
| C. | 38.1 mm (1.5 inches) |
| D. | 44.5 mm (7/4 inches) |
| Answer» A. 25.4 mm (1 inch) | |
| 68. |
According to ASTM E709-95 and API, the temperature of the dry particles can be usable up to: |
| A. | 38ºC |
| B. | 2000ºC |
| C. | 49ºC |
| D. | 315ºC |
| Answer» D. 315ºC | |
| 69. |
According to ASTM E709-95 and API, the thickness of non conductive coatings will not exceed: |
| A. | 1-10 mm |
| B. | 2-5 mm |
| C. | 0.02-0.05 mm |
| D. | 0.001-0.004 mm |
| Answer» C. 0.02-0.05 mm | |
| 70. |
According to ASTM E709-95 and API, relevant indications are produced by: |
| A. | Greasy surfaces |
| B. | Excessive background |
| C. | Leakage fields |
| D. | Rotating Eddy currents |
| Answer» C. Leakage fields | |
| 71. |
According to ASTM E709-95 and API, when fluorescent particles are used, the UV bulb shall warm up prior to use for at least: |
| A. | 1 minute |
| B. | 2 minutes |
| C. | 3 minutes |
| D. | 5 minutes |
| Answer» D. 5 minutes | |
| 72. |
According to AST M E709-95 and API, after removing magnetization of parts after examination, the residual magnetism shall not exceed (1 gauss = 0.0001 tesla): |
| A. | 3 × 10-4T (3gauss) |
| B. | 4 × 10-4T (4 gauss) |
| C. | 6 × 10-4T (6gauss) |
| D. | 8 × 10-4T (8 gauss) |
| Answer» A. 3 × 10-4T (3gauss) | |
| 73. |
According to ASTM E709-95 and API, a linear indication is defined as an indication in which the length is equal to or greater than the width by a factor of: |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 74. |
According to API, a non- relevant indication is defined as an indication which in the major dimension is equal to, or less than: |
| A. | 1.59 mm (1/16 inches) |
| B. | 2.4 mm (3/32 inches) |
| C. | 3.2 mm (1/18 inches) |
| D. | 4 mm (5/32 inches) |
| Answer» A. 1.59 mm (1/16 inches) | |
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