Sample Specification Questions Wet Magnetic Particle Testing Method

Question 1

1. The magnetic particles suspended in the bath shall have:

a. high red iron oxide content
b. low retentivity and low permeability
c. low retentivity and high permeability
d. high permeability and low coerciveness

Answer 1

c. low retentivity and high permeability

Question 2

2. The ammeter is used to:

a. determine the polarity of magnetization
b. determine the amperage being used
c. ensure that the part has been demagnetized
d. measure amp-turns

Answer 2

b. determine the amperage being used

Question 3

3. The field meter is used to determine:

a. magnetic polarity and amperage
b. the comparative strength of field and if
demagnetization is effective
c. retentivity and magnetic permeability
d. both a and b

Answer 3

b. the comparative strength of field and if
demagnetization is effective

Question 4

4. Demagnetization is required:

a. as soon as the part has been cleaned
b. prior to magnetic particle inspection
c. for all parts which are inspected
d. where residual magnetism will interfere with
subsequent processes or usage

Answer 4

d. where residual magnetism will interfere with
subsequent processes or usage

Question 5

5. Part position is varied in the coil when the part
   is:

a. over 46 cm (18 in.) in length
b. over 31 cm (12 in.) in length
c. square
d. round

Answer 5

a. over 46 cm (18 in.) in length

Question 6

6. Inspected parts requiring repair must be:

a. reinspected using a sampling plan
b. reinspected following repair
c. inspected with another NDT method
d. made to follow the original fabrication plan
after defect removal is checked and reworked

Answer 6

b. reinspected following repair

Question 7

7. Ultraviolet light intensity requirements specify:

a. a minimum of five minute warm-up
b. that a darkened room be used
c. a minimum of 800 pWIcm2 at the inspection
surface
d. all of the above

Answer 7

c. a minimum of 800 uW/cm2 at the inspection
surface

Question 8

8. The ammeter shall be checked against a
   calibration shunt meter:

a. prior to each use
b. at the start of the shift
c. per Procedure M-1
d. per Procedure M-4

Answer 8

c. per Procedure M-1

Question 9

9. Pam will be demagnetized by:

a. banging with a hammer
b. placing within a demagnetizing coil for 30 seconds
c. holding within the demagnetizing mil while
the stepdown transformer moves through its
descending order of amperage shots
d. setting the demagnetizing current at an
amperage higher than the original magnetizing
current and slowly passing the part through the coil

Answer 9

d. setting the demagnetizing current at an amperage higher than the original magnetizing
current and slowly passing the part through the coil

Question 10

10. When magnetizing a part, 31 cm (12 in.) long by 64 mm (2.5 in.) diameter, by placing it within the head stocks and passing an electric current through it, the ammeter should be set at:

a. 900A
b. 1750A
c. 1875A
d. 2200A

Answer 10

d. 2200A

Question 11

11. For demagnetization, the maximum “on” period
    should seldom be more than:

a. 5 seconds
b. 30 seconds
c. 120 seconds
d. 240 seconds

Answer 11

b. 30 seconds

Question 12

12. If a pan cannot be fully inspected as required by the drawing:

a. a drawing revision must be issued
b. the part must be scrapped
c. a nonconformance report must be issued
d. the part must be marked with red paint
pending disposition

Answer 12

c. a nonconformance report must be issued

Question 13

13. The sequence of “shots” shall be determined by:

a. accessibility of areas
b. descending order of current
c. ascending order of current
d. this is not an important consideration

Answer 13

c. ascending order of current

Question 14

14. Unless otherwise specified, magnetic particle inspection shall be performed by:

a. the residual method
b. the continuous method
c. both a and b
d. none of the above

Answer 14

b. the continuous method

Question 15

15. Unless otherwise specified, the final magnetic particle inspection shall be performed on parts:

a. prior to final machining but after final heat
treatment
b. after final machining but before final heat
treatment
c. after final machining and beat treatment
d. any time prior to final heat treatment

Answer 15

c. after final machining and beat treatment

Question 16

16. The extent of magnetic particle inspection should
    be specified:

a. in the procedure
b. in the drawings and in the purchase order
c. in the acceptance standard
d. by normal shop practice

Answer 16

b. in the drawings and in the purchase order

Question 17

17. The technique sheet shall be approved by:

a. a Level II
b. a Level III
c. no one; techniques used do not need to be
approved
d. a Level II and the client

Answer 17

b. a Level III

Question 18

18. If the magnetizing current is not specified, the magnetizing current should be determined by:

a. experimentation and then recorded on the
technique sheet
b. the cognizant engineer
c. the client
d. the technician’s experience

Answer 18

a. experimentation and then recorded on the
technique sheet

Question 19

19. Nonrelevant indications:

a. have no bearing on the suitability of the part
for service
b. shall be reexamined to determine whether an
actual defect exists
c. must be completely removed
d. both a and b must be considered

Answer 19

d. both a and b must be considered

Question 20

20. The intensity of the ultraviolet light shall be
    measured using a:

a. Light meter with a 10X multiplier disc
b. Light meter with an amber field filter
c. light meter set at 343 nm (3425 A)
d. light meter with an M2 rating

Answer 20

a. Light meter with a 10X multiplier disc

Question 21

21. A part being demagnetized should be slowly
    removed from the magnetic field in a straight line for a distance of:

a. 31 cm (1 ft)
b. 61 cm (2 ft)
c. 122 cm (4 ft)
d. the distance is not important

Answer 21

c. 122 cm (4 ft)

Question 22

22. Records of inspection shall be maintained:

a. for the life of the part
b. for 40 years
c. for 7 years
d. until the client accepts the part

Answer 22

c. for 7 years

Question 23

23. A field indicator shall be used to determine the :

a. amount of residual magnetism remaining in a Part
b. orientation of the magnetic field
c. overall vector component of the magnetic field
d. outer limit of magnetic field

Answer 23

a. amount of residual magnetism remaining in a Part

Question 24

24. The part shall be post-cleaned:

a. by rinsing it with acetone
b. by wiping it with a dry cloth
c. by wiping it with a cloth soaked in base oil
“c”
d. this is not a provision of the procedure

Answer 24

c. by wiping it with a cloth soaked in base oil
“c”

Question 25

25. Demagnetization may often be improved by the use of:

a. the DC surge technique
b. insulated paramagnetic rails
c. the ‘Transient Current Method”
d. a booster-type demagnetizer

Answer 25

c. the ‘Transient Current Method”