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"The
Power Plants of the Pan-American Exposition"1
The
Pan-American Exposition at Buffalo is served with power from three
separate plants, one devoted chiefly to exterior decorative illumination,
the second to power for service, partially intended as an exhibit,
and the third largely to pumping machinery for the operation of
most of the various fountains. The first plant is entirely electrical,
utilizing high-tension current from Niagara, and is an exhibit plant,
consisting of General Electric apparatus, next to the regular floor
space given to that company in the Electricity Building. A chief
point of interest lies in the use of 25-cycle current for lighting
in lamps of 8 candlepower. The second plant marks an interesting
combination of a purely initial utility plant augmented by a large
number of show steam and electric machines which have proven of
considerable value, as the demands for power greatly exceed the
first expectations. In this are supplied both direct and alternating
current. Steam is generated in a large battery of vertical boilers
burning natural gas. The whole plant is housed in one building located
at the northwest corner of the grounds. The third plant contains
both steam and gas engines for driving pumps and a number of steam-electric
units. It is altogether an exhibition plant, occupying a central
court several feet below the general floor-level in the Machinery
and Transportation Building. Steam is carried to it from a boiler
plant across the canal from the building, 200 feet distant. Natural
gas is used in both boilers and gas engines.
The Niagara
current, from the Niagara Falls Power Company, enters the grounds
at one side near the service plant) in six conductors on a single-pole
line. Through the grounds to the Electricity Building it is carried
underground in lead sheathed conductors boxed in wood, but its admission
into this circuit is controlled by means of a water rheostat consisting
of three tanks corresponding to the three conductors of the three-phase
current. Large blades lowered into these tanks by motors close the
circuit gradually, and the incandescent lights throughout the grounds
are brought slowly to full illumination, the period lasting about
80 seconds and affording a spectacle which is waited for every evening
by the sight-seeing crowds. The rheostats are enclosed in a wooden
house built on posts above the ground and operated at that point.
The motor, however, may be controlled from the service plant and
the Electricity Building.
At
the Electricity Building, the high-tension current, which is at
about 11,000 volts, is stepped down to 1800 volts, and for that
purpose there are 19 transformers of an aggregate of 4,750 kilowatts,
together with oil-break switches and a blue marble switchboard of
fourteen panels. The 11,000-volt feeders pass first through an oil-break
switch enclosed in a brick chamber extending above the floor and
operated by a small motor controlled from the switchboard. They
then rise through the floor and are carried overhead across six
compartments on triple petticoat insulators on light angle-iron
frames. Opposite each compartment the feeders are tapped and the
branches are connected to auxiliary oil-break switches in each compartment.
These compartments are formed of brick partitions 4 inches thick,
cement bottom, 2-inch stone tops and sheet-steel doors, lined with
asbestos. Each switch is operated from the switchboard, two on each
of three panels. Leaving the switches they pass through the floor
into a large cellar room about 7½ feet high, with brick walls,
asbestos board ceiling and wood floor. In this all the connections
are made to the transformers and the forced blast of air for the
transformers, which are of the air-cooled type, is discharged into
it. The branch high-tension leads from the switches go east to a
set of three transformers which are connected in delta, the nineteenth
transformer being in reserve. The secondaries are connected similarly
and the 1,800-volt wires are run to points below the switchboard,.
where they rise to oil-break switches placed immediately behind
the board.
There are three
switchboard panels devoted to the six sets of 1,800-volt wires,
and each line is protected with a circuit breaker. Three bus bars
extend along behind the board at the top, and these are supplied
from the secondary feeders from the oil-break switches, and in turn
supply outgoing feeders through similar hand-operated oil-break
switches with circuit breakers on the face of the board, these also
grouped in pairs, twelve feeders in on six panels. The six 11,000-volt
switches are of about 32 amperes capacity, the six 1,800-volt switches
on the line from the transformers, of amperes, and on each outgoing
feeder 136 amperes. The first panel of the board contains a polyphase
meter and a time-limit relay, besides a voltmeter on swinging bracket.
The transformers are air cooled, as stated, and there are two single-inlet
Buffalo Forge Company centrifugal blowers, each electrically driven
by direct-connected 110-volt motor running at about 375 revolutions
per minute. The transformers require one-half ounce air pressure.
The
power plant at the northwest corner of the grounds, the combination
service and exhibit plant, occupies a large frame and plainly temporary
building, 170 x 200 feet in plan. It is of the type in which there
is a longitudinal dividing wall separating the boiler and engine
rooms, the boiler room occupying probably one-quarter of the space,
and the engine room practically all the rest; the switchboard is
on the opposite side of the room from the boilers. The boilers are
of the vertical type, 19 in all, placed in a single row, and all
connected for burning natural gas, the gas burners entering at the
front and the main supply gas header extending across in front of
them on the floor. On the back side of the station building are
the steam railroad tracks and a siding is provided for coal delivery,
with coal storage open from the firing space. Considerable coal
is already on hand, so that in the event of temporary failure of
the gas, coal may be relied on to prevent a break in continuous
operation. At the middle point of the coal-storage space is a small
extension or shed, in which is located the boiler-feed apparatus.
This consists of Snow steam pumps, one 10 x 6 x 10, a compound one
8 x 12 x 7 x 12, and another compound with double water ends 6½
x 10 x 6 x 10, and five injectors, the latter installed side by
side in the same room, in cross-connection on the feed line.
The steam from
each boiler, which is maintained at a pressure of about 110 pounds,
is taken from the top, and each steam pipe enters into the top of
a steam header supported overhead and pitching toward one end for
drainage. It is supported by wrought-iron pipes, two pipes at each
point, these being bedded by flange ends on foundation piers for
the purpose and the two rising inclined toward each other, connecting
at the top by elbows into the ends of a short, straight piece of
pipe on which the steam header rests. The branches to the various
engines rise in the usual manner from the top of the main, pierce
the division wall and drop to the engine cylinders. In general each
has a right-angle elbow at the base of the drop, and into this is
inserted a drip pipe for relieving such water as might otherwise
get into the engine cylinders. The exhaust is carried under the
floor to two Otto feed heaters, filters and oil separators.
The boilers
are also provided with an induced draft apparatus put in by the
Buffalo Forge Company. This is a duplex installation, located on
a platform in the engine room under which an oil room has been partitioned
off. Each fan is direct connected to a Buffalo Forge Company horizontal
steam engine.
There are at
present 12 steam engines in the building, some, as stated, comprising
the original service equipment and the others, new machines installed
as useful exhibits. They all drive electric machines by belt, so
that steam engine and generator run at suited speeds and there were
not the delays sometimes experienced in connecting two such machines
directly, a condition which floor space did not make of first demand.
There are 16 65-light Brush arc-light dynamos, arranged in four
sets of 3 each, driven from simple engines made by the John T. Noye
Manufacturing Company, by separate belts on the same driving flywheel.
The remaining four are belt-driven in pairs from Armington &
Sims engines of the center crank type with two flywheels, each carrying
a driving belt. The arc machines are 2,900-volt 9.6-ampere dynamos.
Direct current
is furnished for other purposes at 550 volts by four 200-kilowatt
Westinghouse generators driven by compound Armington & Sims
engines and at 125 volts by two 45-kilo-watt Westinghouse generators
driven by a simple Armington & Sims engine. Two-phase alternating
current is supplied at 60 cycles in a 2,400-volt 300-kilowatt Stanley
generator, driven by an engine made by the Phoenix Iron Works and
in a 2,200-volt 180-kilowatt Westinghouse generator belted to a
Buffalo Forge Company engine of the tandem-compound type. A Stanley
frequency charger of 80-kilowatts capacity to charge from 25 to
60 cycles per second, at the time of writing, had yet to be put
in place.
In one of the
front corners of the building, that is, distant from the boiler
room, are located the fire pumps in connection with the fire extinguishing
system about the grounds. This is a small room of brick with concrete
arched ceiling, to have as high a degree of fire-resisting qualities
as practicable. It contains three Snow duplex fire pumps of 16 x
9 x 12-inch cylinder dimensions and of 750 gallons per minute capacity
at a speed of 70 revolutions per minute. The room is fed with steam
in a pipe carried across the building under the roof trusses. It
is supported in a manner similar to that in which the main header
behind the boilers is carried. The supports in this case are 20
or 25 feet high with the two incline stanchions about 18 inches
apart at the top and 3 feet at the bottom. The corresponding opposite
corner of the building is framed in for use as a store room. There
is a small refrigerating set in the station used in connection with
the principal catering establishment on the grounds. This consists
of a Buffalo Refrigerating Machine Company compressor and two Hall
pumps.
The switchboard
is made up of a number of sections, each section In general being
furnished by the maker of the electrical machinery which it controls.
There are four white marble panels for direct current with double-pole
switches of single-throw and circuit breakers, ammeters and rheostats.
Next to these are two blue marble panels for the Stanley machines,
then three panels with Westinghouse Instruments, two for direct
current with three-pole switches to include equalizer and the third
for the Westinghouse two-phase alternator with arrangement for two
feeders. Finally are three sets of feeder plugs for the arc lights.
It will thus be seen that the switchboards simply serve to control
the machines, the current then being distributed to switchboards
or controlling devices at points of use; similar in a way to the
decorative light distribution, in which the 1,800-volt circuits
are carried about the grounds to transformers stepping down to 104
volts at which pressure the lamps are wired in parallel.
The plant in the center
of the Machinery and Transportation building is, as stated, a number
of feet below the general floor level, roofed off in the open court
about 4 feet above the floor. At each end It will be accessible
by a stairway and there will be a public gangway down the center.
It is about 100 x 200 feet in main dimensions. Along one side are
spaced 12 rotary pumps, all driven by belt-in one case by a rope
drive-from prime movers which lie along the longitudinal axis. Between
these and the other side of the room are a number of electric-generating
units and condensing apparatus.
The pumps were
all made by the P. H. & F. M. Roots Company, and eight of them
are of a capacity of 2,500 gallons per minute, and four of 1,500
gallons capacity. Seven of the larger are driven from steam engines,
while the eighth and the small ones are all run from gas engines.
The larger pumps run at 180 revolutions per minute and the smaller
at 260 revolutions per minute, maintaining 100 pounds pressure;
all discharge Into a header which subdivides Into two mains, one
for the main electric fountain arid the other for practically all
the rest. The engines driving the pumps are primarily exhibition
machines, and, of course, of different powers. In order from one
end, they are an American Ball of its well-known compound type,
a Sioux City tandem-compound made by the Murray Iron Works of Burlington,
Ia., of a Corliss type with a 16-foot flywheel carrying a rope drive
to the pump pulley, an Ames Iron Works, of the simple center-crank
high-speed type, a Lane & Bodley, Cincinnati, Twentieth Century
engine, of the simple type with a two-eccentric Corliss valve motion,
a Harrisburg Standard tandem-compound four-valve engine, a Fitchburg
Steam Engine Company's two-eccentric engine and a Watertown, N.
Y., Engine Company's simple four-valve engine, these concluding
the steam engines; and a large vertical three-cylinder gas engine
made by Struthers, Wells & Co., driving the eighth of the large
pumps, a vertical three-cylinder Nash gas engine made by the National
Meter Company, a Bessemer horizontal two-cylinder two-cycle engine,
cylinders side by side, made by the Bessemer, Pa., Gas Engine Company,
a Walrath vertical three-cylinder throttling governor engine, made
by the Marinette Iron Works Manufacturing Company, and a Buffalo
tandem horizontal engine, the last four running the smaller pumps
and all using natural gas.
The steam-electric
units Include an American Ball dynamo directly driven by an American
Ball engine, a 126-volt Onondaga dynamo direct-connected to a simple
Straight Line engine, a Keystone generator belt driven from a Skinner
automatic simple engine made by the Skinner Engine Company of Erie,
and a Keystone dynamo in direct connection with a Ball engine made
by the Ball Engine Company of Erie, Pa. Some of the steam engines
are run condensing, and for that purpose a large Wheeler surface
condenser is installed, the exhaust approaching it from opposite
directions, the two exhaust mains rising from under the floor and
connecting with a Cockrane oil separator in each case before entering
the condenser. The condensation is returned through a large Cockrane
feed-water heater and purifier which receives and condenses steam
for the engines operated non-condensing. Two Snow feed pumps take
care of the return of the water to the boilers.
The boiler
plant for the steam machinery in the Machinery building is located
in a separate building across the canal from it. It is about 60
feet square in plan, and contains four 500-horse-power Morrin Climax
boilers built by the Clonbrock Steam Boiler Works of Brooklyn. They
are arranged for burning natural gas, a gas main encircling each
near the bottom and feeding 20 burners. A steam pressure of about
126 pounds is maintained and the steam is carried from the boiler
house in an 18-inch main partly underground, covered with about
2 inches of hair and partly on a bridge crossing the canal to the
end of the Machinery building. Two injectors are also available
for feeding purposes cross-connected on the feed line from the Snow
pumps.
The
officials to whom credit is due for the general planning of the
work described and the supervision of its many details are: Director-General,
Hon. William I. Buchanan; Director of Works, Mr. Newcomb Carlton,
M. E.; and Chief of the Mechanical and Electrical, Bureau, Mr. Henry
Rustin. Mr. Luther Stieringer is consulting engineer on electric
illumination; Mr. J. H. Murphy, general superintendent of building
construction, and Mr. Harry Weatherwax, chief draftsman.
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