GE Sensing PanaFlow Z1G User Manual

GE

Measurement & Control

PANAFLOW Z1G:

TIGHT GAS WELLHEAD FLOWRATE
MEASUREMENT

For over 30 years, Panametrics owmeters from GE have proven to be the most reliable solution
for challenging gas ow measurement applications. With proven reliability in are gas, stack gas
and steam, GE’s robust transducer technology is ideal for shale gas and coal seam gas wellhead
applications. In short, GE oers the most reliable ultrasonic meter available, plus local service when
and where you need it.

Flare Gas Flow Measurement: The Ultimate Reliability Test

As a pioneer in ultrasonic transit-time ow measurement, Panametrics distinguished its owmeters by
providing reliable gas ow measurement solutions in extremely harsh applications for the past three
decades. Joining the GE Measurement & Controls group in 2004, provided Panametrics with greater
technical reach, and improved greater resource access, resulting in even greater improvements in
ultrasonic transducer design.

How can you be sure that your owmeter will operate reliably in something as challenging as a shale
gas or coal seam methane wellhead application? Choose a owmeter with a proven track record
of reliable operation in an even more dicult application! Since the development of the world’s rst
ultrasonic owmeter for are gas applications in 1980, GE has been the market leader with over
7,000 installations in an application with gas compositions from 2 g/mol to over 120 g/mol, ow
velocities from 0.1 ft/s to over 394 ft/s, and process temperatures from -160oC to 280°C. The world’s
best performance and vast experience in this dicult application translates directly to outstanding
performance in shale gas and coal seam gas ow measurement.

Flowmeter Reliability Starts With A Reliable Transducer

Reliable ultrasonic ow measurement starts with transducer sound wave signal amplitude and signal to
noise ratio (SNR). In shale gas or coal seam gas applications, these signals can be weakened from sulfur,
coal ne or other condensate build up on the transducer face.

imagination at work

1

Solids accumulating on the transducer face act like a
muer and attenuate the signal. As this scaling continues
to accumulate, the transmitted and received ultrasonic
signals continue to degrade, which results in reduced signal
amplitude and degraded SNR. The pictures below are
from two dierent locations of working transducers, pulled
for routine maintenance. The better the SNR and signal
amplitude exhibited under ideal conditions, the better the
transducer will be able to hold up under harsh conditions.

GE’s transducers are driven by an industry high 170 volt
pulse, providing very high signal amplitude. This high power
requires an explosion proof enclosure design, (Ex d rating)
to meet hazardous area certication requirements. Other
transducer designs, meet hazardous area certication
requirements by simply being intrinsically safe (Ex ia).
Although intrinsically safe transducers work well in
clean applications, they are not well suited to handle the
challenges presented in shale or coal seam wellhead gas
ow measurement, due to the high level of condensates in
the gas stream

It’s not complicated. Less power means less signal.

Fluctuating Well Head Flow Rates Require
High Turndown Ratio Metering

Throughout the lifecycle of a coal seam well, ow rates
can uctuate considerably as a result of changing well
conditions, therefore it is important to select a meter with
a high turndown ratio to assure a long service life. The
Panaow Z1G has a turndown ratio of 240:1, measuring
ow rates as low as from 0.5 ft/s and as high as 120 ft/s,
and under pressure conditions that are below atmospheric.
Under higher ow conditions, background noise degrades
SNR, however, with the industry highest signal amplitude,
GE transducers overcome this obstacle.

When you have millions of dollars invested in a shale gas
or coal-seam gas well, you need reliable, accurate gas ow
measurement. As the gas moves from the well distribution
network to the gas gathering station for processing,
understanding well production trends is a critical element
in natural gas production eciency. As wells age, gas
production levels are unstable. This information is a critical
part of knowing which wells are producing with maximum
eciency, and which are in need of maintenance.

Despite this signicant amine crystal

build up, these transducers continued to

operate reliably

Glycol carry-over and dirt on this

transducer was not enough to stop GE’s

robust transducer technology in this

pipeline gas application

Maintaining a wellhead is a costly proposition. This is
especially true if the well is in a remote location, requires
special land access permitting or both. Visitation to
the wellhead should be limited to well production

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PanaFlow Z1G Ultrasonic Flowmeter