Page 55 - Petroleum and Gas Field Processing

Figure 21 Schematic of sucker rod pumping.

the bottom-hole pump (Fig. 21). The pump may be thought of as
a cylinder-plunger system with one-way valves. Produced fluids
enter the cylinder above the plunger during the down stroke and
are lifted to the surface during the up stroke.
2. Hydraulic Pumping (HP): In this method, a pump located at the
bottom of the well is powered by high-pressure fluid. The
function of the pump is to increase the produced fluid pressure
to lift it to the surface with the desired wellhead pressure.
Figure 22 shows a schematic of hydraulic pumping facility. The
surface facility provides the high-pressure hydraulic fluid that
powers the pump. Hydraulic fluid may flow through a closed
circuit and does not come in contact with the produced fluids.
Oil may also be used as the hydraulic fluid, allowing its mixing
with the produced fluids. The major limitations of this method
are the need for expensive centralized hydraulic power units and
expensive clean hydraulic fluid.

Copyright 2003 by Marcel Dekker, Inc. All Rights Reserved.