Iron County news. [volume] (Hurley, Wis.) 1913-1950, 1920-01-10

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 a steam tur'
bine direct, connected to a powerful generator
This generator is operated by the steam turbine
and produces the current we have been seeking
Each of the turbO-generators produces 14,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
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 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 a correcting link be-
tween this highspeed .Lrbne and the low-speed
motor which drives the propelers, Mechanical
gears which in the turbine driven vessel have
heen used to reduce the turbine speed down to
suitable propeller speed, are entirely eliminated
and the necessary reduction accomplished by sim"
nile electrical means. Moreover the operating
units of vital importance each inclosed 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 so grouping the machinery,
the apparatus from shell fire. grounding and col
lisbon We might say that this feature plus the
hexiiuity OF control and the ability to cut off
defective or damaged apparatus constitutes one
of the essentle! superiorites Of electric drive"
To follow the power route to its source, we must
go still further forward to a point amidshtps.
Here are nine huge steam boilers arranged three
in a compartment. They store up the steam I'M
der pressure of go 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 10 two
turbines The two turbines operate two genera
TORS The two generators produce electrical cur
rent The electrical current is led through copper
cables IN n control station where it Is distributed
and passed on to four h.g motors. Each Of the
four motors turns propeller and thus the ship
is driven through the water
The current which the two turbo- generators
producs 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 u.
inch and 14-inch guns blowers which supply the
ventilation of the ship electric fans. telephones
heaters pumps refrigeratng machinery. wireless
apparatus kitchen appliances, laundry equip
ment etc to say nothing Of the lighting system
Motor-driven machinery also operates the boar
cranes and the anchor windass. There are scores
of storage batteries which stand ready to keen
the electric lights going should the main lighting
system fail. It has been estimated that there are
aboard the New Mexico no less than so electric
motors
where does the current come from to operate
thern?" we ask 1t comes from six auxiliary
turbogenerator sets and we find two Of tAenn well
M toward the bow Of the vessel still on the Same
level as the boiler room from which we have lust
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 go upward through the
New Mexico. There are four separate decks