December 1954 page 7

83-Ton
Spare Tire

[image: locomotive under maintenance]
A worn truck is removed from locomot

Locomotives get new wheels in multiples of four complete wh

ON a railroad the term "truck" seems
to be a bit out of place. But in ac-
tuality railroad trucks are a vital part
of every piece of rolling stock.

Trucks are the wheel assemblies which
included the wheels, axles, brake mech-
anisms, bearings, traction motors, and
other important components of a loco-
motive or box car. They are entities in
themselves and can be removed and re-
placed in entirety by jacking the body
up and rolling the truck from under-
neath.

Removing, reconditioning, and replac-
ing heavy diesel locomotive trucks is
getting to be a commonplace operation
at the P & N's Greenville mechanical
shops. In the few years that the diesel
locomotives have been in operation shop
personnel have performed the Herculean
task 22 times.

Although the process involves the lift-
ing of 83 tons of machinery, it is a rela-
tively simple procedure. When a truck
assembly has been under a locomotive for
a certain amount of mileage, usually
between 125,000 and 150,000 miles, it is
ready for reconditioning. In a period of
a few hours the entire locomotive is
lifted on four 35-ton-capacity mechanical
jacks, the work truck is disconnected
from the locomotive, rolled from beneath
it, and a reconditioned truck removed
previously from another locomotive takes
its place. After about five hours on the
jacks the locomotive is ready to go back
into service.

Trucks are overhauled

When a worn truck is removed from
a locomotive it is thoroughly cleaned by
steam and then moved to the machine
shop for dismantling and rebuilding. The
wheels are lathed, thus re-establishing
the all-important flange. Felt packing in
the bearings and gear cases is replaced,
and the entire truck is repainted and
relubricated. Once this has been done,
the truck is ready to be placed under the
next locomotive. By having one spare
next locomotive. By having spare trucks
for each type of locomotive the P & N
is able to make repairs of this sort with-

8 SEMAPHORE