Figure 2.26. Gage for Measuring Worn Journal.
journals have reached condemning lengths rather than because they have reached condemning diameters.
f. Collar worn to limit (AAR symbol 85-D). The new dimensions for collar thickness for A and B axles
are 5/8 inch, for C and D axles 3/4 inch, and for E and F axles 7/8 inch. When the end collar on any axle
reaches 3/16 inch measured with the wheel-defect gage, the axle is removed from service. If the gage will fit on
the collar, the axle is condemnable.
g. Journal diameter worn below limits (AAR symbol 86-D). When through normal wear, or through re-
turning, the diameter of the journal reaches the wear limits, the axle must be removed from service. Outside
h. Wheel seat worn below limit (AAR symbol 86-A). Outside calipers are also used to measure the
diameter wear of wheel seats. When condemning limits are reached, the axle is removed from service.
Transmitting the weight of the car and its lading from the journal bearing to the wheels and keeping the
wheels in gage are the two functions of railway axles. There are solid axles used only with friction bearings;
and solid and tubular axles used with either friction or roller bearings. All axles are rated according to their
load capacity established by the size of their journals. Axles with the smallest journals and the least load
capacity are designated A, and the largest