Surface Machinery and Methods for Oil-Well Pumping

PRIME MOVERS AND POWER PLANT MACHINERY.

SPECIAL CONDITIONS.
a. The total charge is the sum of the demand and energy charges given
above.
b. Service under Schedule a will be supplied by the company at a standard
distribution voltage of 2,200 volts or more depending upon the distribution
voltage obtainable. Service under Rate B will be supplied by the company
from its main transmission line at the transmission line voltage.
c. The maximum demand in any month will be the average kilowatt de-
livery of the 15-minute interval in which the consumption of electric energy
is greater than in any other 15-minute interval in the month. The maximum
demand on which the demand charge will be based will not be less than 60 per
cent of the demand occurring during the 11 preceding months.
d. Any demand occurring between the hours of 11 p. m. and 6 a. m. of the
following day will not be considered in determining the above demand charge.
HORSES USED FOR POWER.
In some of the older fields of northern Pennsylvania, the horse
whim was common until recently, chiefly at wells where much sand
was in suspension. With modifications as to detail this is now a
common method of handling production in Rumania.
The horse whim, as formerly built in the shallow oil fields of
Pennsylvania, consisted of a wooden shaft about the length and
thickness of a bull-wheel shaft, with the gudgeons attached. The
shaft was placed vertically with the gudgeons resting in timber bear-
ings, the bottom one being flush with the surface of the ground and
the upper one being held in position by braces to the derrick. At
the upper end of the shaft, a flanged drum 10 to 12 feet in diameter,
with a 12 to 15 inch face was built. This drum was used for wind-
ing the three-quarter inch manila rope used in bailing. Through
a mortise at the bottom of the shaft, one end of a pole about 10 feet
long was inserted. A horse was hitched to the outer end of this
pole and driven around in a circular track with the vertical shaft
of the whim as a center. In this way the rope was wound on
the drum and the oil raised from the well in the bailer. When
the bailer reached the surface, the oil was dumped into a barrel or
small tank, placed on the floor of the derrick, and the bailer was re-
turned to the bottom of the well by its own weight unwinding the
rope on the drum, the horse having been unhitched.
CHOICE OF POWER.
The choice of power depends chiefly upon the cost and availability
of fuel and equipment as well as on the conditions under which the
power is to be used. Steam, gas, or oil engines built in large units
serve as prime movers in centrally located electrical power plants.
Built in smaller units they serve as prime movers in the smaller
power plants at groups of wells. In still smaller units they as well as

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George, H. C. Surface Machinery and Methods for Oil-Well Pumping. Washington D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc12407/. Accessed December 27, 2014.