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

Chapter XI
16-INCH PROJECTILE HOIST,
MARK7 ANDMARK7, MODS. 1 AND2
General Description
1. The projectile hoist equipment installed in each
turret comprise the three hoist assemblies designated in the
ti tLe , These are identically arranged in all turrets: - The
right gun being served by the Mark 7 design, while the center
and left guns are served by Mark 7, Mods. 1 and 2, respectively.
2. These designs are hydraulic ram type tubular lifts
of rack and pawl arrangement. They are independently driven
and controlled and are similar in all essential features. They
resemble the main battery projectile hoists of recent heavy
cruisers, cf., U.S.S. New Orleans, etc., with principal dif~
ferences from that type in that they are reversible and are
equipped with power mechanisms for operation of the cr ad.Le;
Each such hoist is an assembly of hoist tube and platform structure
together with power units, a cradle and control devices.
These subassemblies are designated and are separately described
as follows:-
Hoist tube and platforms
Hoist cylinder and rack assembly
Power drive assembly
Cradle assembly
Cradle operating power unit
Tube pawl and tripping cam opera ting mechanisms
Hoist con trol, interlock and indicator arrangements.
3. The outboard hoists are alike but to opposi te hand.
Their courses are vertical from the lower end to the pan floor
and slope thence rearward 16°-40 1 to the cradle. The center
hoist differs from the outboard machines in that the course is
s traigh t all the way, nearly vertical, and the rack casing,
doors and other elements have different position or arrangement.
All cradles are aligned between their respective rammers and
guns, and when open extend the rammer track, at gun loading
angle, from the rammer to the gun breech.
4. Functionally all hoists are' alike. Each operates
to raise or to lower projectiles by equal stages. A stage of
movement is equal, to full stroke (97.5 inches) of the power
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