CAST STEEL WHEELS NOT HAVING FLAT BACK FACE OF RIM
ALL OTHER STEEL WHEELS
Figure 4-3. Method of measuring high flange.
k. Out of Round. Wheels which are out of round in
the entire tread and into the plate. Thermal cracking is a
serious defect and in any stage of development is cause
excess of 3/64 inch within an arc of 12 inches or less with
for immediate removal of the wheel from service.
use of the gage as shown in figure 4-11 must be removed
from service. This rule applies only to 33-inch wheels.
n. Cracked or Broken Plate. A wheel with a
l. Cracked Hub. Hub failures take the form of
cracked plate is condemnable and must be removed from
service. Cracks in the plate develop due to stresses from
radial cracks, as illustrated in figure 4-12 which shows the
service loads and braking.
Most plate cracks are
back hub of the wheel. They usually occur during
progressive in nature. It is
m. Thermal Cracks. Thermal cracks are caused by
intensive brake heating. They occur crosswise on the
tread or flange. In extreme cases, they may go through