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prime mover to suitable pumping speeds. Figure 20.3 shows the
essential components of the surface pumping equipment.

Figure 20.3 - The surface equipment of a sucker rod pumping
installation

Speed reduction is accomplished at the gear reducer, and the
rest of the surface equipment is concerned with change from rotary
to reciprocating motion and with counterbalance.
The direct linkage between the sucker rod string and the
surface equipment is the polished rod. Polished rods are available
in three sizes, the size for any particular installation depending on
the tubing size and the diameter of the sucker rods at the top of the
rod string. The polished rod passes through a stuffing box, and
fluid which has been lifted passes to the flow line through the
pumping tee.
Near the upper end of the polished rod is a polished rod
clamp, which is supported by the carrier bar. The carrier bar, in
turn, is supported by flexible cables (called the bridle) which pass
over the horse head at the end of the walking beam. Proper design
of these components assures vertical travel of the polished rod,
thus reducing unnecessary wear and friction losses at the stuffing
box.

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