American Oil and Gas Reporter - June 2017 - 99

SpecialReport: Artificial Lift Technology

Artiﬁcial Lift Makes Every Dollar Count
By Dan Holder

The technologies that help operators
find and produce oil and natural gas continue to evolve, with service companies
combining production equipment in new
ways and incorporating novel scientific
techniques to ensure those resources continue to flow to the surface.
Electric submersible pumps and beam
pumpjacks have been the go-to artificial
lift solutions for years, but even those industry workhorses are being challenged
by the technical demands of increasing
total well depth as operators extend everlengthier laterals to 10,000-plus feet to
tap more of the reservoir interval. At the
same time, commodity prices are forcing
producers to continue to make the most
of every dollar invested.
Fred Morrow, vice president of engineering for Superod, says while longer
laterals increase production and recovery
rates, the high initial outputs eventually
will fall. He suggests operators consider
adding to their artificial lift arsenals hydraulic pumping units equipped with
fiberglass sucker rods to maximize the
advantages of both technologies.
With a stroke as long as 300 inches,
hydraulic pumping units provide a range
of advantages to keeping deeper wells
profitable, Morrow says, including lower
operating costs, reduced wear on a pumpjack's rod string because of fewer cycles
and reduced workover costs.
Multiple wells drilled on a common
pad also are prime opportunities for hydraulic units because of space limitations,
Morrow points out. "Operators used to
drill a well at a spot out in a field, and
there was just the one well there," he
says. "Now, operators are drilling from
pads with several wells in very close proximity to one another. A surface hydraulic
unit probably has a third of the footprint
area of a conventional pumping unit."

Working With Hydraulics
Hydraulic pumping units are becoming
more common in the field, Morrow assesses. Features that make them especially
attractive for the artificial lift community
include the ease of changing the stroke
speed and length through an onsite control
panel, he says.
"The biggest challenge is not that hydraulic pumping units are harder to operate,

but they are different," Morrow poses.
He describes a scenario in which a well
may have several rod failures or tubing
leaks each year that cost an operator as
much as $150,000 to correct.
"Rod failures and tubing leaks tend to
be seen as an acceptable expense. Installing
a hydraulic unit may cost $50,000 more
than a pumpjack, but if it eliminates the
problems, that operator is money ahead
a year into the operation. Looking at
only the capital cost of a hydraulic unit
does not tell the entire story. If it stops
tubing leaks or rod failures, why not go
with a hydraulic unit?"
Operators pondering their artificial lift
options often have concerns about the
reliability of hydraulic pumping units,
but Morrow says regular maintenance
procedures allay most of those fears.
"It is true that hydraulic units eventually
leak. But, hydraulic systems have been
around for many years," he lays out.
"Hydraulic cables and connectors have a
certain cyclic life. Modern aircraft are
taking hydraulics to the nth degree. For
the aircraft industry, it is a predictable
maintenance issue because those hydraulic
units have so many cycles before they
fail. The success to hydraulic pumping is
understanding the loads and the cycle
life before failure."
Operators must accept that at regular
intervals, the hydraulic pumping units
must be taken out of service and overhauled, Morrow outlines. He adds too
many companies handle repairs as they
happen, replacing a broken hose one
month only to come back three months
later to fix a leaking connector.
"It is a day's job to replace all the
wear items on a hydraulic unit," he says.
"Those systems are designed to go a certain number of cycles. When you get to
that cycle life, you replace these parts at
one time. It is much, much cheaper."

Using Fiberglass Rods
While fiberglass sucker rods excel
with a pumpjack's shorter strokes and
faster speeds, Morrow notes their lower
weight make them ideal to replace steel
rods for artificial lift applications.
"Consider a 10,000-foot deep well.
The steel rod strings weigh 22,000- 25,000
pounds," he says. "A fiberglass string in
that exact same application may weigh
14,000 pounds. A hydraulic unit has to

have a lot more horsepower to lift that
extra 10,000-15,000 pounds in the steel
string."
Fiberglass rods also offer improved
performance in deviated borehole settings,
Morrow says. With side loads between
the rods and the tubing in a directional
well proportional to the tension in the
rod string, guides wear faster with steel
rods. That leads to increased wear in the
tubing and rods, he indicates.
Boreholes full of corrosive fluids and
gases are another environment where
fiberglass rods provide superior performance, Morrow asserts. "Fiberglass is the
same material they make acid tanks out
of. There has never been a corrosion
failure in a fiberglass rod body," he notes.
Steel sucker rods are more suitable in
high-temperature situations, Morrow says,
pointing out that standard fiberglass rods
have a temperature limitation of about
200 degrees, while some fields have
downhole temperatures as hot as 275 degrees. "High temperatures soften the
matrix that holds the glass fibers together,
and the rods fail," Morrow says, although
he adds that high-temperature fiberglass
rods are available.
Industrial Internet of Things
The Industrial Internet of Things
(IIOT), the technique of using wireless
connections to enable most pieces of
equipment to send and receive data, is
firmly entrenched in the oil and gas
sector, but its potential is only starting to
affect operators' profit margins. Peter
Zornio, chief technology officer at Emerson Automation Solutions, says his company is expanding its IIOT abilities in
artificial lift applications by adding OSIsoft's PI System™ to new devices. He
describes the software suite as a highly
scalable data aggregation and visualization
infrastructure used by both large and
small energy companies.
"The PI System connects to various
data sources-whether it a distributed control system, a programmable logic controller or a supervisory control and data
acquisition system-and pulls together the
real-time streaming data from the multiple
sources," he says. "That is used to build
reports and visualization of data, but it
also becomes a platform to write applications, such as the dynamic lift application
(DLO)."
JUNE 2017 99

American Oil and Gas Reporter - June 2017

Table of Contents for the Digital Edition of American Oil and Gas Reporter - June 2017