b. Throwing. Track may be thrown or moved manually by men using lining bars, such as the one
shown in figure 1.7, or by a machine, such as the track liner pictured in figure 1.22. By either method, the track
is moved the proper distance from the tacks on the line stakes or the ties. When a track gang equipped with
lining bars is to throw the track, part of it works on each rail. They move the entire track as a unit at each station.
Figure 3.9
shows how the men and bars are positioned. To
make the throw easier, ballast may be removed from
around the ties. The track liner does the same work
as the track gang equipped with lining bars. Only
one operator is needed where three to eight men
with bars would be required on each rail.
3.31.
RE-DRESSING BALLAST
After the track has been thrown, the original
ballast section must be restored, and the ballast must
be tamped. If a station requires an extremely long
throw, the ballast section may have to be widened.
The outer rail must also be raised to proper
superelevation. Usually when a curve is out of line,
its superelevation has changed and is no longer
Figure 3.9. Throwing Track With Lining Bars.
correct. Most railroads publish tables
showing the superelevation to be used for various curvatures and speed limits.
3.32.
SUMMARY
Make your stringline calculations carefully and keep them accurate. Make your final throws as small as
possible--no more than 6 inches, especially when the gang has to move the tracks with lining bars. Revise your
proposed ordinates, several times if necessary, to arrive at a smooth curve with short throws.
Mark or stake the track after you make your calculations, to show the gang how far to throw the track at
each station. On a double track, use a scratch board to mark one of the tracks. Place the board on one of the rails
and scratch a mark on the nearest tie of the
90
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