supports the underframe and superstructure. To connect two cars, a coupler
is used. An automatic one is used in the United States and in some oversea
areas while the hook-and-link coupler is common in others. The draft gear
joins the coupler to the underframe and absorbs the coupling shock as well
as that which comes from sudden acceleration or from pulling stresses.
The various designs of railway car superstructures serve many
purposes, but the major components and the preventive maintenance on them
are the same. This is generally true for rolling stock found in theaters of
operations. Preventive maintenance on railway cars is important because it
increases the availability of this equipment and decreases the possibility
Inadequate maintenance ties up equipment in repair tracks
Of all the components of railway equipment, the truck assemblies
receive the greatest amount of maintenance and require the most attention.
The preventive maintenance checks of the truck assembly can be divided
into four groups: the general truck assembly, truck brake rigging, journal
boxes, and wheels. They are discussed in the next