TM 55-203
one. To remove the end sill, it is necessary to take the
(2) Center or side sills which are bent down at either
grab irons and uncoupling lever casting off If the sill has a
end usually can be straightened by chaining the
cover plate, the cover plate should be removed. After the
underframe firmly to the rails at the body bolster and
sill is stripped, the coupler should be removed, and the
jacking under the end of the affected sill. If the sill is bent
striking casting, corner braces, and diagonal braces
up at the ends, it may be firmly secured from the
removed The old grab irons and uncoupling lever
underside at the ends and the frame can be jacked up at
castings, if undamaged, may be replaced on the new sill.
the center. If the sill is bent down in center, both ends
The new end sill is then put in place and riveted or welded
may be secured firmly at the body bolsters and jacks may
to all connecting parts. Broken end sills can be repaired,
be placed under the center. Jacking up will restore the
if necessary. The striking casting is removed and a patch
underframe to its former position.
flanged to cover the top leg of the sill, extending down the
face of the sill and riveted (or welded) both to the face
and to the top leg. This patch must be at least 24 inches
5-14. Diagonal Braces
long and of heavy material.
These braces extend from the body bolster and the top
c. Bent Sills
flanges of the center sill to the top flanges of the end sills
and side sills. These braces may break, or the gusset
(1) If a sill is badly bent, it must be removed for repair
plates which fasten the braces at each end may break In
Such sills should be heated in a furnace and straightened
either case, the diagonal braces and the gusset slates
under a press. Sills bent out of line to one side or the
usually are cut out and replaced. The rivets at the points
other can be straightened by placing the underframe In a
of connection must be cut to release the braces
jacking stall where it may be jacked back. Whether a
jacking is used or not, the procedure is the same. Jacks
5-15. Striking Castings
should be placed against the point farthest out of line.
Anchor jacks can be placed at the most convenient points
When these castings are broken or badly damaged they
along the sills, depending upon the extent of the bend.
should be cut loose and replaced.
Jacking both ways will restore the sill to its former position
Rivets are burned or cut off, then punched out, the old
When jacking such sills into 'line, it is always best to jack
striking casting removed, and a new one riveted into
them slightly past the point of alinement. This permits
place.
them to spring back to some extent toward their original
set when the jacks are released.
Section IV. RIVETING
the place where they are to be used: button, cone,
5-16. General
countersunk, and steeple. The button head is the most
common type, because it is most easily formed. In
In car repair work, rivets are universally used for holding
repairing tank car interiors, cone head rivets are used
plates together or joining plates to structural shapes or
because they are strong and do not chip easily. Steeple
members. In most instances where splicing is done,
head rivets are used in the floors of hopper cars because
cover plates are required. These cover plates are secured
they have the least tendency to retard the bulk loading
by rivets to the structure or member repaired. Rivets
when the car is being dumped. The countersunk head is
generally are heated in portable compressed air operated
used where a finished flat surface is required, such as a
forges; however, one or two rivets for a small job can be
place where the part riveted and the rivet heads are to be
satisfactorily heated by an acetylene torch Standard
covered by a plate, or where clearance is required
practices and safety precautions should be observed
between moving riveted parts.
while riveting (DA Pam 551). The rivets used in all
riveted splicing should be the same as the existing types
b.
Rivet Length.
The proper rivet length is
in the underframe.
determined by the thickness of the parts to be joined. The
rivet must be long enough to project beyond the rivet hole
5-17. Types of Rivets
and leave sufficient shank so that a head can be formed
at the end. The length of shank necessary to form a head
a. General. Rivets used in freight car work have four
varies
different
types
of
heads,
depending
on
5-7
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