Figure 1.20. Gasoline-Powered Drill to Make
Track-Bolt Boltholes.
Section III. Tie Renewal
1.18.
GENERAL
The final phase of track rehabilitation is tie renewal. Like surfacing and rail renewal, tie replacement
may be done singly (spot) or out of face. Because the life of ties varies greatly, good and poor timbers are
usually found intermingled. When this occurs, out-of-face replacement is seldom done. An instance where it
might apply would be on a rundown line being built up to handle a heavy increase in traffic. When both ties and
rail are to be renewed, it is generally better to lay the new rail first. However, ties should not be replaced during
a rerailing operation unless they are completely rotted. If the new ties were placed first, the old rail would have
to be spiked to them. Then, before spiking new rail to the new ties, the old spike holes would have to be filled
with wooden tie plugs and then the spikes driven into the plugged holes. By installing the new ties last, the
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