Surface Machinery and Methods for Oil-Well Pumping Page: 111

                                
POWER TRANSMITTING MACHINERY.

much lost production. To correct this difficulty a small electric
motor driving a unit pumping power was installed at each well, and
the operation of each motor controlled by a switch located on the
river bank.
For driving pumps and compressors, motors have proved just as
satisfactory in oil-field practice as in mining and other industries.
Plate XXVIII, A (p. 110), shows a new type of 15 to 35 horse-
power oil-well motor direct-coupled to turbo-gear, which in turn is
direct-coupled to the pulley driving the band wheel at wells pumping
on the beam.
WELL PULLING-MACHINES.
In the early days of the oil business, all wells were pulled with a
steam engine, bull wheels, and the other drilling equipment left in
place for pumping, after the well had been completed. This method
is still used at many places, noticeably where the wells are pumped
individually on the beam.
At other wells where the steam engine has been replaced by a
gas engine for pumping, the pulling of rods and tubing is often
done with the reversible clutch attachment on the gas engine, shown
in Plate VII, B (p. 22).
At still other wells pumping on the beam where electric power
has replaced the steam or gas engine, the motor used is often the
2-speed, c2-power type designed both for pumping and pulling.
Sometimes, however, as previously mentioned, a motor of a rating
suitable only for pumping is installed at the well, and a larger
motor powerful enough to pull any of the group of wells to be
served is moved to the well to be pulled, aligned outside of and in
back of the motor house, the belt connecting the pumping motor to the
band well is removed, and power for pulling is delivered from the
motor mounted on the truck to the band wheel by means of a longer
belt carried with the larger motor for this purpose. See Plate
XXVIII, B (p. 110).
Recently one of the larger California oil companies has adopted
the practice of installing a winch for pulling at each of its wells
pumping on the beam. This hoist is equipped with a clutch and is
chain-driven from the tug on the band wheel, as shown in Plate
XXIX, A.
In many oil fields, since adoption of the central power or jack
plant, all mechanical equipment has been removed from the indi-
vidual well, the derrick alone being left in place. Pulling was for-
merly done by using horses and a set of tackle blocks to increase the
power. More recently, mechanical devices have replaced horses, such
as a winch mounted on a truck, as shown in Plate XXIX, B,

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