T.O. 33B-1-1
Figure 1-9.
Ketos Ring
Table 1-4.
Ring Specimen Indications
Type of
D.C.
Minimum No. of
Suspension
Amperage
Holes Indicated
1400
3
Non-f luorescent
2500
5
3400
6
1400
4
Dry Powder
2500
6
3400
7
1400
3
Fluorescent
2500
5
3400
6
A.C. Amperage
Non-f luorescent
1000
1
Dry Powder
1000
1
Fluorescent
1000
1
1.6.10.2
QQIs.
Test specimen(s) used with QQIs offer a more versatile means of checking system performance than afforded
by the Ketos ring. The specimens can be real parts or designed to be representative of the most challenging
inspection to be currently performed. This combination is capable of providing an adequate check on any
magnetic particle inspection system. Even though QQIs respond to the applied, not residual, field,
demagnetization is necessary of the specimen(s) in order to remove the previously applied inspection media.
1.6.10.3
Cracked Parts.
The ultimate specimens for the performance tests are cracked parts. If available, they require careful
handling to remain corrosion-free and retain their f law sizes.
1.6.11
Ammeter Check.
Amperage indicator accuracy check SHALL be performed using the calibrated ammeter/shunt authorized in
TA-455. Operation of the ammeter/shunt SHALL be according to the commercial manufacturer’s operating
instruction. DC amperage variations exceeding 10% at reading or +60 amperes, whichever is greater, and
Change 2
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