By CLEM A. COPELAND.
Consulting Engineer, Los Angeles, Cal.
The large and deep-lying oil-sand lakes and subterranean gas works,
commencing with the southern rim of the Santa Maria Valley and stretching
away for a dozen miles southward toward Santa Barbara, contribute some
14,600,000 barrels of high gravity refining and fuel oil to California’s
annual production of 40,000,000 barrels.
[Illustration: WEST FRAME OF 2600 FT. SPAN. POWER-HOUSE IN BACKGROUND.]
With the assistance of two eight-inch pipe lines 32 miles to Port
Harford, a similar line 48 miles across the Isthmus of Panama, and a
goodly fleet of vessels, the Union Oil Company scatters this oil from
Seattle to San Diego, and from New York to Japan. Chile also has a share
for the working of its nitre beds and its railways.
The little towns of Santa Maria and Orcutt receive with open pipes a
tithe of the gas which nature has here stored, and which would otherwise
escape the many safety valves, while the steam rig engines have often
been run with direct gas pressure from the wells.
This land of gas and gushers is difficult of control, and is always ready
to pop off at from 100 to 400 pounds pressure through the many 3,000-foot
tubes which puncture its depths. When a new gusher is brought in, it
sprays the adjacent hills with a glistening shadow of petroleum and is no
respecter of persons or property. One new and frisky fury flowed 12,000
barrels per day, and delivered 4,000,000 cubic feet of gas every 24 hours
for four months, gradually dropping to a production of 7,000 barrels,
which it maintained for nearly a year, finally diminishing to 3,500, and
now, after three and a third years, is still producing 250 barrels per
day, having delivered during this time 3,000,000 barrels of petroleum,
and enough gas to last San Francisco for three years. This is, with
perhaps one exception, the most remarkable well in the history of oil
industry, and is widely known as “Hartwell No. 1.”
The district contains two groups of wells, one contiguous to Orcutt,
and the other near Lompoc. Danger from fire due to the excessive gas
pressure of the Orcutt fields is exceedingly great, as evidenced by the
burning of four “rigs” in the first two years of its history, during
which time there were fifteen wells brought into production. The cost of
these “rigs” exceeded the cost of the lighting plant, which is described
in these notes, and no fires have since occurred in the sixty wells now
producing. The advisability of the plant is therefore quite patent.
[Illustration: MAP OF ORCUTT OIL FIELDS ELECTRICAL DISTRIBUTION SYSTEM.]
The lighting system employed in the Orcutt oil fields is perhaps
only interesting in illustrating how the methods employed in large
undertakings may be used to great advantage in the smaller enterprises to
effect a large saving and to simplify conventional methods. The smaller
undertakings often afford opportunities of saving a larger percentage in
cost and operation in connection with the larger ones. In the present
instance, an economy of $9,000 was made in a system which would have cost
$30,000 if constructed along conventional lines.
As may be seen from some of the views in these notes, the country covered
by the system is very hilly and stony, hard sandstone being everywhere
prominent. Trees would have interfered considerably over perhaps a third
of the line with ordinary construction, and being oak, it would have cost
heavily to eliminate them. Although the winters in this section are very
bleak and windy, no snow has ever fallen. The attached map shows the
wells, which are unusually far apart and scattered over some 5,000 acres
of land.
[Illustration: FRAME BETWEEN 1500 AND 1600 FT. SPAN.]
Long span work, employing copper cables, and using the oil-well derricks
for support, seemed well to meet these and all other conditions in the
most economical fashion. The adoption of long span work effected a large
saving in the length of line and wire needed to cover the territory,
since air-line routes could be covered in all cases across country,
without any care being taken to lay out a pole line which would conform
to some general inflexible plan. Moreover, much vertical distance was
saved in not having to follow the contour of the country. Incidentally
the long span work makes the installation of new pieces of line very easy
and simple, and no large amount of material need be kept on hand for
expansion purposes.
Where conditions are rapidly changing, as in the present instance,
existing lines having to be moved because of the abandonment of wells
or re-arrangement as new wells come in amongst the old ones, are easily
changed, with but little loss of labor and material. The derricks, 80
feet in height, make ideal supports for long-span construction, and steel
frames, heavy enough for the largest size of wire, eventually were made
of “scrap” pipe set in cement. Where the derricks were not available,
redwood “dead-men” were also used between derricks which were near
together, but on opposite sides of rises or hills. The present system
of distribution is 72,550 feet, or 13.75 miles, in length, and consists
of 70 derricks, 9 frames, and 10 “dead-men,” making the average span
about 800 feet. The seven-strand bare copper cables used in this work
were furnished under rigid specifications previously described in the
“Journal,” by the Standard Underground Cable Company. One will observe
from the map and photos that there are many spans 1,500 feet in length,
one span of 2,000 feet between derricks and one 2,600 feet from one frame
to another. The sags allowed correspond to 60 feet on a 2,000-foot span,
and the cables were very small for such work, No. 6 being used for the
greatest lengths, which occurs as a neutral on the longest spans. The
sizes used are Nos. 2, 4, and 6.
As the cables were suspended high above the ground and good construction
was relied upon for safety from breakage, they were used without
insulation, and a large saving was thus effected. “Goose-egg” strain
insulators, first designed by the writer several years ago, are used to
insulate the cables. Copper sleeves were used to splice the cables and to
loop them to the insulators.
It is of considerable interest to observe the action of these light
cables in a high wind, for even in the most gusty storms there is no
whipping action. In the longer spans, the cables hang absolutely parallel
and sway in a most deliberate manner from 12 to 25 feet out of line.
[Illustration: HARTWELL NO. ONE.]
[Illustration: DETAIL OF DERRICK CONSTRUCTION.]
Inasmuch as fuel economy is of little importance, since either waste
gas or oil can be used, a large drop in the distributing system is
permissible, and a radius of three or four miles from the power-house
can be economically attained by the use of 210 to 250 volt lamps on the
three-wire direct-current system. At present the maximum distance is 255
miles, and four voltages of lamps are employed. The derricks are wired on
the two-wire system with No. 14 T. B. W. P. medium, hard-drawn wire, care
being taken to keep all wires on the outside of derrick house wherever
possible. Although the wires and insulators have been in some cases
completely sprayed and saturated with oil from the gushers, no troubles
of insulation have been experienced.
At the time this work was started, there was a small plant on the Pinal
Oil Company’s property near by, where keyed sockets were used until one
of the drillers was injured by a gas explosion caused by turning off
one of the lights. This, of course, suggested the care necessary to
guard against such accidents. In the present installation, double-pole
fuses were constructed for each derrick and tank house, by using two
weatherproof sockets and Edison plug fuses, all inclosed in a gauze
cylinder like a Davy mine lamp. Switches for tank house and derricks
were also inclosed in gauze. In wiring the derricks, sleeves were used
for splicing, so that in the whole system no solder nor torch was used.
Specially designed heavy wire lamp guards and portables, with wires
inclosed in cotton-covered garden hose, are other features of the derrick
wiring. When drilling is commenced, the derrick is wired for eleven
lights. Tank houses, some fifteen or twenty in number, are wired with a
light over each tank.
[Illustration: POWER-HOUSE.]
The power-house is of only passing interest, being designed for
reliability and minimum first cost, and with the idea of transplanting
it to some new location should future conditions dictate. The view shows
two 10×10 Shepherd engines, clutched to either end of a shaft, from which
two 45-kilowatt, 250-volt, direct-current Westinghouse generators are
belted. In case of accident to one generator, a switch on the switchboard
converts the 3-wire to a 2-wire system, using the two outside wires as
one, and the neutral as the return conductor. Three 48×14 fire-tube
boilers supply steam at 125 pounds pressure. The power-house is in a
perennially cool location on a hill crest, so that it could be made small
and cozy.
The system has been in uninterrupted and satisfactory operation for
two years. The only trouble during the time was caused by one wire of
one span breaking, due to an imperfection in splicing. The section has
long-continued and severe winds, much rain and cold weather, but two
winters have developed no imperfections. Although the lights burn all
night, no interruption has been experienced. Reliability is important,
since, if the lights failed, there would be a temptation to light candles
or lanterns at a critical time.
The system was designed and supervised by Mr. Copeland, of Messrs. Clem.
Copeland and F. R. Schanck, consulting engineers for the Union Oil
Company. Mr. C. W. Crawley, who is at present electrical superintendent,
was foreman of construction.
ALCOHOL vs. GASOLINE FOR POWER.
The Technologic Branch of the United States Geological Survey, under the
direction of Mr. J. A. Holmes, has recently completed an elaborate series
of tests on the relative value of gasoline and alcohol as producers of
power. The tests, over two thousand in number, probably represent the
most complete and exact investigation of the kind that has been made,
either in this country or abroad, and includes much original research
work.
Correspondingly well-designed alcohol and gasoline engines when running
under the most advantageous conditions for each, will consume equal
volumes of the fuel for which they are designed. This statement is based
on the results of many tests made under the most favorable practical
conditions that could be obtained for the size and type of engines
and fuel used. An average of the minimum fuel consumption values thus
obtained, gives a like figure of eight-tenths (.8) of a pint per hour per
brake horsepower for gasoline and alcohol.
Considering that the heat value of a gallon of the denatured alcohol is
only a little over six-tenths (.6) that of a gallon of the gasoline,
this result of equal fuel consumption by volume for gasoline and
alcohol engines probably represents the best comparative value that can
be obtained for alcohol at the present time, as is also indicated by
continental practice. Though the possibility of obtaining this condition
in practice here has been thoroughly demonstrated at the Government
Fuel-testing Plant, it yet remains with the engine manufacturers to make
the “equal fuel consumption by volume” a commercial basis of comparison.
The gasoline engines that were used in these tests are representative
of the standard American stationary-engine types, rating at 10 to 15
horsepower, at speeds of from 250 to 300 revolutions per minute, while
the alcohol engines were of similar construction and identical in size
with the gasoline engines.
The air was not preheated for the above tests on alcohol and gasoline,
and the engines were equipped with the ordinary types of constant level
suction lift and constant level pressure spray carburetters. Many special
tests with air preheated to various temperatures up to 250° Fahrenheit,
and tests with special carburetters were made, but no beneficial effects
traceable to better carburation were found when the engines were handled
under the special test conditions, including constant speed and best load.
The commercial completely denatured alcohol referred to is 100 parts
ethyl alcohol plus 10 parts methyl alcohol plus one-half of one part
benzol, and corresponds very closely to 94 per cent by volume or 91 per
cent by weight ethyl alcohol (grain alcohol).
No detrimental effects on the cylinder walls and valves of the engines
were found from the use of the above denatured alcohol.
The lowest consumption values were obtained with the highest compression
that it was found practical to use; which compression for the denatured
alcohol ranged from 150 to 180 pounds per square inch above atmosphere.
Eighty per cent alcohol (alcohol and water) for use in engines of the
present types would have to sell for at least 15 per cent less per
gallon than the denatured alcohol, in order to compete with it. The
minimum consumption values in gallons per hour per brake horsepower for
80 per cent alcohol is approximately 17.5 per cent greater than for the
denatured alcohol used, or for gasoline. A series of tests made with
alcohol of various percentages by volume ranging from 94 per cent to 50
per cent, showed that the minimum consumption values in gallons per hour
per brake horsepower increased a little more rapidly than the alcohol
decreased in percentage of pure alcohol. That is, the thermal efficiency
decreased with the decrease in percentage of pure alcohol. This decrease
in thermal efficiency or increase in consumption referred to pure alcohol
is, however, comparatively slight from 100 per cent alcohol down to about
80 per cent alcohol. Within these limits it may be neglected in making
the calculations necessary to compare the minimum consumption values for
tests with different percentages of alcohol.
The nearer the alcohol is to pure, the greater the maximum horsepower
of the engine. The per cent reduction in maximum horsepower for 80 per
cent alcohol as compared with that for denatured alcohol used, was less
than one per cent, but the starting and regulating difficulties are
appreciably increased.
With suitable compression, mixtures of gasoline and alcohol vapors
(double carburetters) gave thermal efficiencies ranging between that for
gasoline (maximum 22.2 per cent) and that for alcohol (maximum 34.6 per
cent) but in no case were they higher than that for alcohol. The above
thermal efficiencies are calculated from the brake horsepower and the low
calorific value of the fuel, which for the gasoline was 19,100 British
thermal units per pound, and for the denatured alcohol was 10,500 British
thermal units per pound.
As has been previously published, alcohol can be used with more or
less satisfaction in stationary and marine gasoline engines and these
gasoline engines will use from one and one-half to twice as much alcohol
as gasoline when operating under the same conditions. The possibilities,
however, of altering the ordinary gasoline engines as required to obtain
the best economies with alcohol are very limited; for the amount that the
compression can be raised without entirely redesigning the cylinder head
and valve arrangement is ordinarily not sufficient, nor are the gasoline
engines usually built heavy enough to stand the maximum explosive
pressures, which often reach six and seven hundred pounds per square
inch. With the increase in weight for the same-sized engine designed to
use alcohol instead of gasoline, comes an increase in maximum horsepower
of a little over thirty-five per cent (35%), so that its weight per
horsepower need not be greater than that of the gasoline engine, and
probably will be less.
The work was taken up to investigate the characteristic action of fuels
used in internal combustion engines with a detailed study of the action
of each fuel (gasoline and alcohol) as governed by the many variable
conditions of engine manipulation, design and equipment. These variables
were isolated, so far as possible; their separate and combined effects
were determined; worked out under practical operating conditions; and
led up to the conditions required for minimum fuel consumption. The
results show the saving that can be obtained over conditions for maximum
consumption, and also establish a definite basis of comparison under
conditions most favorable to each fuel. This latter is a point of much
commercial interest, and a study of the comparative action of gasoline
and alcohol may be of great service in solving some of the general
internal-combustion-engine problems where other than liquid fuels are
used.
A large number of fundamental tests were necessary in order to clearly
define conditions and interpret results. In a way they follow the work
conducted by the Department of Agriculture, supplementing to a certain
extent, but not duplicating bulletin 191, which gives much data of
general value.
Many of the tests of internal-combustion engines have been made, but
most of them, especially in this country, were by private concerns,
for a specified purpose, and the results are not generally available.
Furthermore, as is generally recognized by those familiar with gas, and
especially gasoline-engine operation, the conditions influencing engine
performance are so numerous and varied as to make the value of offhand
comparison very limited and oftentimes misleading, exact comparisons only
being possible under identical conditions or with reference to the actual
known differences in all conditions that influence the results.