OP-755 Part 2 Pages 197-401 - Personal Page of GENE SLOVER

234
cylinder piston and attached rack. And at the upper end such
stroke is equivalent to delivery of a projectile above the cradle
proj ec tile latch. Total lift to that position is four
st~ges from the lower handling platform, three from the upper
handling platform.
Hoist Tube and Platforms
5. structurally the tube and rack casing sections are
a bolted assembly supported from the lower and upper platforms
and braced by flange attachment at the shelf plate, pan floor
and elec tric deck. The cradle unit is aligned with the tube
but is mounted on and secured to the shelf plate. The arrangement
Ls as shown on drawing number 215941 for the outboard
hoists, and drawing number 215946 for the center hoist.
6. In each such assembly the two platforms are the
founda tion elements for the hoist tube, the door assemblies
and the power cylinder-rack casing group. These platforms are
similar large steel castings arranged with top surfaces flush
with the stowage levels and the rotating rings. The platforms
are accurately machined and keyed to lac ate and secure door
and shutter brackets, rack casing sections and the cylinder.
The latter is vertically mounted between the platforms and extends
through both with the upper cylinder head and piston rod
crosshead coupling located immediately above the upper platform
level.
7. Door and shutter brackets are substantial cast steel
columns which structurally support the hoist and hoist load
above. They are arranged with virtually full opening of the
hoist-way vertically in each stowage compartment and with the
several openings fitted with hinged doors and shutters.
8. The moving rack is an assembly of connecting bars,
links and pawl carriers arranged with crosshead as shown by
figure 43. The units are the same in right and left hoists.
Center hoists with straight casing track for the entire course
of rack movement are similar assemblies of fewer parts.
Hoist Cylinder
9. The hoist cylinder, located as described in paragraph
6, is an assembled arrangement of steel tube cylinder,
cast bronze cylinder heads and piston-piston rod as shown by
the sectional view of drawing 216379. This is a hydraulic ram
of 5.875 inches bore and 97.5 inches stroke. It operates at
maximumpressure of 700 pcunds+ per square inch when lifting
Lull load of four projectiles. The arrangement of cylinder
* Normal working pressure hoisting full load; relief valves are set for
800 P.S.1.