F Quiz

Question 1

The interpretation of magnetic particle indications may be aided by:
a) observing with a magnifying glass
b) observing the indications as they are formed
c) reproducing the indication residually
d) all of the above

Answer 1

D

Question 2

Residual magnetism may be beneficial as an aid:
a) in the deposition of weld metal
b) in interpretation and evaluation of indications
c) in demagnetization
d) all of the above

Answer 2

B

Question 3

An interruption in the normal physical structure or configuration of a part which produces an MT indication is called:
a) a discontinuity
b) a defect
c) an indication
d) a deformation

Answer 3

A

Question 4

Comparing parts that have been circularly magnetized and those which have been longitudinally magnetized, which retains the most objectionable residual field if not demagnetized?
a) longitudinal
b) circular
c) vectored
d) remnant

Answer 4

A

Question 5

What type of magnetization uses the formula: Ampere-turns= 45,000/L/D?
a) circular
b) longitudinal
c) parallel
d) vectored

Answer 5

B

Question 6

Why are large soft contact areas such as lead or copper braid used for surfaces or headstocks?
a) to increase the contact area and reduce the possibility of burning the part
b) because of their low melting points
c) because the help heat metal, thus facilitating magnetic induction
d) to increase the contact area and flux density

Answer 6

A

Question 7

A gear with case-hardened ground teeth and hub ends is MT tested. Individual indications are detected on five of the teeth and on the one end surface of the hub. Although the indications are very sharp and distinct, they do not break over the edges of the part. What is the probable identity of the indication?
a) grinding cracks
b) inclusions
c) porosity
d) quench cracks

Answer 7

A

Question 8

If an overall pattern (sometimes circular lines) appears on the test surfaces, how should the inspector reprocess the test
piece?
a) retest at a higher amperage
b) demagnetize
c) retest at a lower amperage
d) both a and b

Answer 8

C

Question 9

A prime consideration when selecting a powder to be used as a magnetic particle medium is to select a powder that:
a) provides a high contrast to the surface being tested
b) provides a low contrast to the surface being tested
c) will adhere to the surface being tested
d) requires a high demagnetization current to remove it

Answer 9

A

Question 10

When testing for fine shallow surface cracks, the preferred MT method should be:
a) dry AC
b) dry DC
c) wet AC
d) wet DC

Answer 10

C

Question 11

Which of the following is an advantage of the dry method over the wet method?
a) It is more sensitive to fine surface cracks
b) It is more capable of providing full surface coverage on irregularly shaped objects
c) It is easier to use for field inspection with portable equipment
d) It is faster than the wet method when testing a number of small parts

Answer 11

C

Question 12

When testing a bar with an L/D ratio of four in a ten-turn coil, the required current would be:
a) 45,000 amperes
b) unknown; more information is needed
c) 18,000 amperes
d) 1125 amperes

Answer 12

D

Question 13

Internal splines and holes drilled parallel to or near test surfaces will cause:
a) broad, fuzzy indications directly aligned with the part’s internal contours
b) sharp, well-defined indications directly aligned with the part’s internal contours
c) no indications
d) both a and b

Answer 13

A

Question 14

Some limitations of coil magnetization techniques are that:
a) coil must be of minimum diameter in relation to the part
b) the effective field is generally limited on either side of the coil
c) small diameter parts should be placed close to the coil
d) all of the above

Answer 14

D

Question 15

Which of the following casting defects is caused by non-uniform cooling resulting in stresses which rupture the surface of the metal?
a) shrink
b) hot tears
c) porosity
d) dross

Answer 15

B

Question 16

The term used to refer to the total opposition to flow of current represented by the combined effect of resistance, inductance, and capacitance of a circuit is:
a) inductive reactance
b) impedance
c) reluctance
d) decay

Answer 16

B

Question 17

A coil shot is required to be performed after a head shot using the wet continuous method. In order to properly conduct the coil shot it is necessary to:
a) remove all residual wet magnetic particle fluid from the part using clean, dry absorbent rags
b) demagnetize the part between the head and first coil shot
c) place the part in the coil and continue the inspection after evaluating the head shot indications
d) none of the above

Answer 17

C

Question 18

When adding concentrate to any wet magnetic particle suspension liquid it is common practice:
a) to add powder directly to the suspension liquid
b) to make a small, slurry-like test mixture of the powder
c) both of the above
d) neither of the above

Answer 18

C

Question 19

A desirable property of magnetic particles used for the inspection medium for either the dry or wet method is that they:
a) be non-toxic
b) possess high permeability
c) possess low retentivity
d) have all of the above characteristics

Answer 19

D

Question 20

Which of the following can cause non-relevant indication magnetic particle indications?
a) joints between dissimilar metals
b) brazed joints
c) roughing tool cuts on surface
d) all of the above

Answer 20

D

Question 21

External poles which are too strong to permit good inspection of a part are more likely to result when using:
a) circular magnetism
b) longitudinal magnetism
c) polarized magnetism
d) residual magnetism

Answer 21

B

Question 22

A rough forging discontinuity has the following characteristics: it can occur on the surface or internally; it is associated with processing at too low a temperature; it is often caused by excessive working; and it creates straight or irregular cavities varying in size. How would it be identified or classified?
a) burst
b) shrinkage
c) pipe
d) lamination

Answer 22

A

Question 23

Discontinuities in plate, sheet, or strip caused by pipe, inclusions, or blowholes in the original ingot which after rolling are usually flat and parallel to the outside surface are called:
a) seams
b) laminations
c) cracks
d) laps

Answer 23

B

Question 24

Forging laps occur in what relation to the axial direction of a part?
a) may occur anywhere on the surface and may bear no relation to axial direction of the part
b) always are found on thermal centerline
c) are found on surface of part at a 90 degree angle to long axis
d) may occur anywhere in the part and always run in the direction of working

Answer 24

A