T.O. 33B-1-1
permanent magnet yoke is available for inspection. One typical application of yokes is shown in Figure 3-31.
The yokes SHALL be able to pass the equipment/system tests in paragraph 1.6.7.2c.
Figure 3-31.
Field Inspection of Nose Wheel Strut
SECTION V
MPI MATERIALS AND RESPECTIVE METHODS
3.5
MAGNETIC PARTICLE INSPECTION MATERIALS AND RESPECTIVE METHODS.
3.5.1
General.
a.
An important consideration in the magnetic particle testing process is the use of the proper type of
materials to secure the best possible indications of the particular type of defect being sought under a
given condition. The choice of which materials to use is important, since the appearance of the
particle patterns at discontinuities will be affected by this choice, even to the point of whether or not a
pattern is even formed. Since the results of magnetic particle tests depend on the interpretation of
the particle pattern, the appearance of this pattern is of fundamental importance. The reproducibility
of results by inspectors at different locations is dependent on the same type of particles being used by
each inspector, and the same magnetizing procedure.
Change 3
3-53
