...Railway artillery - Personal Page of GENE SLOVER

621
SUDING MOUNTS (MATbIELS a GIJSEMENT).
535. Guns mounted on sliding carriages are fired from a track
called a firing track or epi, laid on the arc of a circle so as to permit
the orientation of the piece' to cover the field of fire selected. For
firing, beams (poutrelles) are placed pa.ra.llel to the rails and screwed
to the ties; the jacks which relieve the wheel trucks of their load bear
on these beams and provide friction for absorbing the shock of recoil.
536. FIRING BEAMs.-The above platfonns or beams are about
37.50 meters long. This length permits 8 grads (7.2 degrees) field of
fire for a curve of 200 meters radius and 10 grads (9 "degrees) for a
9O-meters curve. They should not be fastened to the ties before the
gun is ready to occupy the position to fire. They are then fastened
with screws in the holes that will be mentioned in the next paragraph.
537. FmING EPI CoN8TRUOTION.-The firing epi for each piece is
A curve constructed with sPecial Trails (45 kilograms) and chamfered
ties (0.15 by 0.30 by 3 meters). Firing tracks ha,:e no super-elevation.
The gauge is from 1.45 meters (4 feet 9.062 inches) for a curve
of 150 meters radius to 1.455 meters (4 feet, 9.312 inches) for the
smallest radius (90 meters). The special ties are not shod, but are
delivered bored ·for track screws. 'They should be spaced 0.54
meters, 0 to 0, on center line of track. Holes are provided in the
ties to receive the screws. for both rails and beams. To prevent
ballast from getting into these holes it is well to plug them with
straw or hard grease. The ends of the tie in which the distance
between the holes for the rail and the beam is the greater must be
laid on the inside of the curve. .After the ties are laid, their proper
position should be verified by running the eyes over these holes,
figure 4, plate 460. Track screws of a standard type and size only
should be used in these ties; nothing else that might change them
or prevent their being used again should be used. At rail ends, the
screws must be carefully screwed down and not driven down with
a hammer.
538. BALLA8T.-The ties should be laid on a bed of excellent
ballast, 0.15 meters (6 inches) thick, extending 1.50 meters beyond
each end of the ties. The tie should be completely buried in the
ballast throughout its length. The resulting bed of ballast will be 4
meters wide at the top and 4.60 meters at the bottom; this will require
about 1.50 cubic meters per meter of track. The ballasting
should be done with special care, the tamping being done preferably
with bars.
539. EPI LIMITS.-An epi is usually defined by its point of beginning
and the direction of its two ends, but to avoid confusion it
Digitized by Coogle