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Magnetic
flowmeters generate more revenues worldwide than any other type of flowmeter. In
terms of units, more differential pressure and variable area flowmeters are sold
annually, but magmeters' higher average selling price enables them to generate
more revenues.
Magnetic
flowmeters -- or magmeters, as they are often called -- have also been
around longer than any other new-technology flowmeter. The Tobinmeter Company
first introduced magnetic flowmeters for commercial use in Holland in 1952 and
Foxboro introduced them to the United States two years later. This puts their
time of introduction well before that of other new technology flowmeters,
including Coriolis (1977), ultrasonic (1963), and vortex (1969). Consequently,
magmeters have had more time to penetrate the markets in Europe, North America,
and Asia. Today more than 60 suppliers worldwide offer magmeters.
We have
recently completed the 7th edition of The World Market for
Magnetic Flowmeters, this study builds and expands on earlier editions in
2001, 2003, 2005, 2009, 2015, and 2017.
The following
are some of the highlights we cover in this comprehensive study:
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Liners are the “secret sauce” of magnetic flowmeters
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Companies are improving magnetic flowmeter technology
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The development of two-wire and battery-powered magnetic
flowmeters.
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The
demand for 2 -wire,
4-wire, and battery-powered meters
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The
displacement of AC magnetic meters with DC types
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The need for
insertion magnetic flowmeters
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The line
sizes where magnetic flowmeters are most frequently used
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The installed base of magnetic flowmeters
Articles
About Magnetic Flowmeters
New developments
While the
magnetic flowmeter market is a mature and stable one, some new product
developments favor continued growth.
One recent
development is the advent and increasing popularity of two-wire magmeters.
Four-wire meters have a dedicated power supply. Two-wire meters use the power
available from the loop-power supply, reducing wiring and installation costs.
While two-wire meters still represent only a small percentage of the total
magnetic flowmeters sold, their use continues to grow.
Another
important development is battery-operated and wireless magnetic flowmeters.
Battery operated meters make it possible to install magmeters in hard-to-reach
places. And wireless meters can transmit a receivable signal where the use of
wires is impractical. Both of these segments represent fast-growing areas of the
magnetic flowmeter market.
Another
recent development in product types is the trend toward lower-cost, compact
magnetic meters in the United States. Compact meters have traditionally outsold
remote meters in Europe, while the reverse has been true in the United States. While
compact meters may be losing some ground to remote meters in Europe, they still
dominate that market.
Why are magnetic flowmeters so popular?
 In
addition to a large installed base, magmeters have many advantages that help
account for their role as the leading revenue-generating flowmeter:
Highly
accurate with no moving parts: Magnetic
flowmeters are highly accurate, do not create pressure drop, and can be used for
custody transfer applications. Magnetic flowmeters do not have moving parts and
provide a highly stable measurement. Their initial purchase cost is medium
to high, depending on size. While their price is generally higher than DP
flowmeters, most are priced lower than equivalent Coriolis meters. In addition,
advanced diagnostics are making magmeters both more intelligent and more
reliable.
Do especially
well in the water and wastewater industry. Most flowmeters do their best work in clean liquids or
gases. Magnetic flowmeters, by contrast, thrive on dirty liquids. They are
used to measure the flow of conductive liquids and slurries, including pulp and
paper slurries and black liquor. Liners are the “secret sauce” of
magnetic flowmeters, enabling them to measure both very dirty and very clean
liquids. They can measure the dirty and caustic liquids and slurries
common to the pulp and paper and wastewater industries, as well as the hygienic
and sanitary liquids common to the food & beverage and pharmaceutical
industries.
Wide range of
line sizes. In
addition to liner flexibility, magmeters are available in a wide range of sizes
from less than 1/8 inch to over 100 inches. Furthermore, the development
of insertion meters gives more options to end users who want to measure liquids
in large line sizes at lower costs.
Top industrial uses
Magmeters are
widely used in the water & wastewater industry. Thanks to
new industry group standards that include using magmeters for water utility
measurement, magmeters are now displacing positive displacement and turbine
meters in some residential and industrial applications.
Magnetic
flowmeters are also widely used in the chemical, food & beverage,
and pharmaceutical industries, due in part to the variety in lining
choices that enable them to measure a wide variety of liquids. Our data shows an
increase in the use of magmeters in these industries.
Magmeters are
also making inroads in oil & gas industry. Magmeters'
main limitation is that they cannot measure hydrocarbons (which are
nonconductive), and hence they have not been widely used in the petroleum
industry. However, they have come to be widely used in hydraulic fracturing to
measure the water injected into oil and gas wells for "fracking" as
well as the water flowing from them for capture, disposal, or recycling.
Flow Research
data shows an increase in both the percent of magnetic flowmeters used in the
oil & gas industry and the percent of magnetic flowmeters used for fracking
applications.
How they work -- AC vs. DC
 Magnetic
flowmeters use Faraday’s law of electromagnetic induction. According to this
principle, a voltage is generated in a conductive medium when it passes through
a magnetic field. This voltage is directly proportional to the density of the
magnetic field, the length of the conductor, and the velocity of the conductive
medium. In Faraday’s law, these three values are multiplied together, along
with a constant, to yield the magnitude of the voltage.
Magnetic
flowmeters use wire coils mounted onto or outside a pipe. A voltage is then
applied to these coils, generating a magnetic field inside the pipe. As the
conductive liquid passes through the pipe, a voltage is generated and detected
by electrodes mounted on either side of the pipe. The flowmeter uses this value
to compute the flowrate.
When magnetic
flowmeters were first introduced, many had coils powered by continuous
alternating current (AC). These devices had the disadvantage that
they were subject to noise that interfered with the proper reading of the meter. As
a result, they needed to be calibrated regularly against an onsite hydraulic
zero to maintain their accuracy.
Direct
current (DC) magmeters were developed to solve the problems from the noise
associated with AC meters. The DC meters are based on pulsed direct current. When
the current is turned on, a voltage is generated in the magnetic flowmeter,
showing the velocity of a flowing liquid. When the current is turned
off, any remaining voltage is assumed to be due to noise. The meter
computes flow velocity by subtracting this extra remaining voltage.
While DC
pulsed technology was first introduced in 1974, it became popular in the 1980s,
and its popularity has grown since then. Many pulsed DC magmeters
have the drawback, however, of lower signal strength. This gives AC
meters an advantage for measuring some dirty liquids and slurries.
To compensate for low signal
strength, some DC meter suppliers developed “high strength” DC meters. These
high strength meters still use the pulsed on-off technology of DC meters, but
they have a higher coil current. This makes them better able to
handle high noise applications -- such as slurries and dirty liquids -- than
standard DC meters. These high strength meters are growing rapidly in
popularity.
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Check out our articles
about magnetic flowmeters, events
occurring in the magnetic flowmeter market before 2010 and our previous
magnetic flowmeter studies:
The World Market for Magnetic Flowmeters, 6th Edition
Released in 2017
The World Market for Magnetic Flowmeters, 5th Edition
Released in 2015
The World Market for Magnetic Flowmeters, 4th Edition
Released in 2009
The Global Market
for Magnetic Flowmeters, 3rd Edition
Provides historical perspective
The World Market
for Magnetic Flowmeters, 2nd Edition
Provides historical perspective
The World Market
for Magnetic Flowmeters, 1st Edition
Provides historical perspective
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