Audubon County journal. (Exira, Iowa) 1884-1993, 1919-10-16

4
another compartment where we view the machine
which generates the electrical current which turns
the propelers.
This is the turbo-generator section. There are
two turbogenerators consisting of steam tur
bine direct, connected to powerful generator
This generator is operated by the steam turbine
and produces the current have been seeking.
Each of the turbo- generators produces l4,OOO
horsepower. In technical language this spot with
in the ship is known as the power plant.
The turbine is an essential part Of this plant 1t
illustrates another advantage Of the electric drive
A steam turbine to operate at Its maximum eff
cheney must revove at a relatively high speed.
say 1000 revolutions per minute. On the other
hand the propeller to be most efficient, must re-
volve with comparative slowness, say 200 revolu-
lions 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 .irbine 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 means. Moreover the operating
units OF vital Importance are each incosed In sep.
arate water-tight compartments. In addition the
machinery Is grouped very close to the center Of
the ship as for as possible away from the sides.
1.-THE possibility Of so grouping the machinery"
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 OF
directive or damaged apparatus, constitutes one
of the essential superiorities Of electric drive"
To follow the power route to Its source, we must
go still further forward to point amidships.
Here are nine huge steam boilers, arranged three
In compartment. They store up the steam un-
der pressure of 250 pounds to the square inch
and deliver 1t 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 1t Is distributed
and passed on to four big motors. Each of the
four motors turns a propeller and thus the ship
is driven through the water.
The current which the two turbo-generators
produce is used entirely in the actual propulsion
Of the vessel The New Mexico must have addi-
tional 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
Motordriven machinery also operates the boat
cranes and the anchor windlass. There are scores
of storage batteries which stand ready to keen
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 It comes from six auxiliary
turbo-generator sets and we find two of them we'll
up toward the bow of the vessel still on the same
level as the boiler room from which we have just
emerged. This turbogenerator, and the Others
similar to 1t, are responsible for the wonderful
applications of electricity which we will make the
acquaintance of as we go upward through the
New Mexico. There arr FOUR separate decks