The St. Charles herald. [volume] (Hahnville, La.) 1873-1993, 1919-11-22

another compartment where we view the machine
which generates the electrical current which turns
the prOpellers
This is the turbO generator section. There are
two turbO- generators consisting Of q steam tur-
bine direct connected to powerful generator
This generator is operated by the steam turbine
and produces the current we have been seeking.
Each of the turbo-generators produces 1900
horsepower. In technical language this spot with
in the ship is known the power plant.
The turbine is an essential part of this plant. 1t
illustrates another advantage of the electric drive.
steam turbine to operate at its maximum eff
cheney must revove at relatively high speed,
say 1000 revolutions per minute. On the other
hand, the propeller to be most efficient, must re
volve with comparative sowness, say 200 revolu-
tons per minute This is because if the propellers
revolved at high speed they would merely churn up
the water and fail to drive the vessel ahead.
Now electricity acts as connecting link be-
tween this highspeed turbine and the low-speed
motor which drives the propellers. Mechanical
gears, which in the turbine driven vessel have
been used to reduce the turbine speed down to
suitable propeller speed, are entirely eliminated.
and the necessary reduction accomplished by sim
pie electrical Moreover the operating
units of vital Importance each Enclosed in sep
arate water-tight compartments. In addition the
machinery is grouped very close to the center of
the ship as far as possible away from the sides
1.-THE possibility of grouping the machinery"
says an officer, means a greater protection of
the apparatus from shell fire, grounding and col
lisiOn. We might say that this feature plus the
fexibility Of control and the ability to cut off
defective damaged apparatus constitutes
of the essential superiorities of electric drive"
To follow the power route to its source. must
go still further forward to a point amidshps.
Here are nine huge steam boilers arranged three
in compartment. They store up the steam I'M
der a pressure Of $50 pounds to the square inch
and deliver it to the turbines. The New Mex
leo burns oil instead Of coal
Thus the electrical propulsion equipment of the
New Mexico may be briefly summarized as fol-
lows: Nine steam boilers deliver steam to two
turbines. The two turbines operate two genera
tors. The two generators produce electrical cur
rent The electrical current is led through copper
cables to control station where it is distributed
and passed on to four big motors. Each of the
four motors turns propeller and thus the ship
Is driven through the water.
The current which the two turbogenerators
produce is used entirely in the actual propulsion
of the vessel. The New Mexico must have addi-
t0nal electrical energy with which to operate
scores of auxiliary apparatus
For instance electric motors operate the 12-
inch and 14-inch guns blowers which supply the
ventilation of the ship, electric FANS telephones
heaters, pumps, refrigerating machinery, wireless
apparatus. kitchen appliances, laundry equip
ment etc, to say nothing of the lighting system
MotOr-driven machinery also operates the boat
cranes and the anchor wiEdlass. There are scores
Of storage batteries which stand ready to keep
the electric lights going should the main lighting
system fail. 1t has been estimated that there are
aboard the New Mexico no less than so electric
motors.
Where does the current come from to operate
them?" we ask. 1t comes from six auxiliary
turbo-generator sets and we find two of them we'll
up toward the bow OK the vessel still on the same
level as the boiler room from which have just
emerged. This turbo-generator, and the others
similar to it, are responsible for the wonderful
applications of electricity which we will make the
acquaintance of as We 80 upward through the
New Mexico. There ara Jour separate decks