Figure 2.14. Shattered-Rim Defect.
Figure 2.15. Spread Rim.
and the wheel should be removed from service and
the condition investigated.
The length of the
spread-rim defect is usually less than 12 inches, and
the spread area tends to flatten out so that it
resembles a large slid-flat defect. It is believed that
the same interior defect causes both the spread rim
and the shattered rim.
d. Shelled tread (Rule 71--AAR symbol 71-E).
Figure 2.16. Shelled-Tread Defect.
When the surface metal of the tread breaks down
and flakes or chips off, the wheel has a shelled-tread
defect, shown in figure 2.16. Extreme defects of
this kind may extend completely around the
circumference of the tread and penetrate to a
considerable depth. When this