The San Francisco call., 1909-09-05
BIG WATER WHEELS
CREDIT TO MAKERS
Power Turbines Installed at
StanisIaus Plant Reflect
Manufacturers Skill
Three Monster Generators to Be
Augmented by Fourth With
Enlarged Capacity

Three busy opponents Of san Fran
essco's supremacy over the entire world
in many lines of manufacture are work
ing dav and night in the power house
of the Stanislaus power company, near
Angels Camp. Cal. proving the efti-
cheney and the quality of machines
made in the shops of the bay region.
They are three Pelton water wheels,
each developing $4,000 brake horse
power. and operating at speed of 400
revolutions per minute, under water
pressure Of 1.475 feet.
These three units, with their genera
tors. represent the highest develop
n1ent of hvdraulie engineering practice
and they are of particular interest be-
cause OF the fact that they are also
the largest tangential water wheel
pnits in the world. When it is consid-
cred that. aside from their monster
size. the wheels have been in success
fuI operation for some time and proven
SO sarfsfactory that the power COM
panV. in charging its plant, mas or
.5ered another TO he placed by the size
Of the three already in operation, some
idea may be gained of the strength OF
these san Francisco made machines ana
their power.
Result OF YEARS OF STUDY
In no factory in the world could
these units be equaied- san francisco
engineers and workmen have devoted
Years of careful study 10 the problems
f7voIved in the wheels construction,
and the theory of hydraulic engineer
ing practice, and San Francisco work-
men. il has been demonstrated time
Ind again. are OF q grade of lntelh-
aence and skill not TO be surpassed
anywhere. The best energies OF engl-
a-eers and workmen alike are put into
the wheels. which, though glahts OF
:heir kind. are built with the care the
watch maker puts into his best work.
y, hint OF the magnitude of the units
may be gained from the statement that
the shaft carrying the generator ana
fhe two oNerhung Pelton wheels Is ~
inches in diameter in the center. taper
ing te I61z inches in the journa Is
supporting this shaft are TWO nine ton
Isi- inch bv 60 inch automatic, self
labrfcating bearings The water
wheels. two being required 10 each
Unit are mounted on the shaft over
hang. so that the three revolving ele-
:neats of the machine are supported
hy but two bearings. insuring the most
compact construction with the fewest
number Of parts. hence the highest
.ffcienCy.
The water for the operation Of the
plant is obtained from the Stanislaus
river. After diversion from the river
channel it is conveyed in a timber
tiume nine feet by six feet for a dis
tauce OF Is miles. The fiume contains
approximately 100000 board feet Of
Jun Der. Its construction involved a
tremendous monetary outlay and ii is SO
rigidly built that railroad tracks are
built on top. over which freight trains
pass. conveying materials used in pow
,r house and dam construction.
GREAT IHPoUNDTNG RESERVOIR
- Twenty four thousand cubic feet of
water per minute is conveyed through
the same to large settling reservoir
or forebay. The body of water i'm
pounded in the reservoir is sufficient
for operating the water wheels for
Is consecutive hours in event of brea k
age along the hume.
Two large steel pressure pipes con-
'ey the water To each of the existing
three wheel units Ia the power plant
and water is discharged upon the
wheels at pressure of $40 pounds per
square inch. To regulate the enor-
nous volume Of water under this high
pressure. specially constructed cast
steel gatevalves are installed of unique
design they being operated by double
reversible Pelton water motors and
auxiliary hand controlling devices for
manipulating the caves in event of ac-
cident to the water motors.
Owing 10 the fiuctuating power re-
cuirements incident 10 the long dis
lance transmission line conveying the
electric current TO the cities on San
Francisco bay. the problem of speed
regulation Of the Pelton wheels called
for precise engineering. Satisfactory
results were obtained by adopting spe-
cial regulating nozzles, two of which
are attached to each wheel unit; these
being actuated by Pelton oil pressure
governors. notwithstanding the fact
that $4,000 horsepower of energy is now
being controlled by these governors,
their operation is so sensitive that no
appreciable speed fluctuations are no.
ticeable when blocks of power aggre-
eating 1000 to 10000 horsepower are
instantaneously thrown on or off the
wheels. It is a well known fact that
the speed of electric generators must
be maintained uniformly and without
undue variation, Irrespective of the
fuctuating demands for power. In
water wheel plants this problem is in
1nitely greater 10 SoiVe than with
steam engines, where only the flow of
steam is to be regulated. In the case
Of this Stanislaus power plant tre-
mendous body of water issues from the
nozzles at speed of over 3.6 miles
per nninte and so finely designed are
the Peiton governors and so sensitive
their operation that they instantly reg
ulate the wheel speed by adjusting the
nozzles, allowing more or less water
70 discharge upon the buckets as oc-
casion demands. Their operation is
prin1a rily effected by oil under press
ure actuating a piston device on the
governors. which is turn is connected
through mechanical devices directly
with the nozzIes. Special safety appli-
snces attached TO the governors cause
the water wheels 10 automatically cease
revolving in the event of accident
ENORMOUS VOLTAGE SECURED
San Francisco will be the terminal OF
the electric transmission line. The
current is generated at a primary volt
age Of 1000. then raised to line volt
age of $4,000 and delivered to the
various substations at approximately
100 600 volts For protection against
lightning, special lightning arresters
have been placed on the outgoing
transmission lines and the whole plant
ssfeguarded to the greatest possible
extent.