HP March 2022 eBook—Energy Transition - 50

Valves, Pumps and Turbomachinery
three thermal cycles, with a leak
rate of less than 100 ppm methane.
* ISO 15848-1, Industrial
Valves-Measurement, Test
and Qualification Procedures
for Fugitive Emissions: This
standard provides the procedures
and requirements for the
mechanical and thermal cycle
testing of valves, with leak tests
at various points. Methane or
helium is used as test media.
Unlike the uncertainty involved in
standard manufacturers' guarantees, the
API's test results are simple to discern:
They are either pass or fail, meaning that
the valve is clearly delineated as low-E or
not. However, those purchasing low-E
valves should understand that the ISO
test methodology is more complicated,
with different " class " ratings that reflect
how the valves perform during testing.
For example, ISO standards allow class
ratings of valves as low-E that do not meet
the " 100 ppm or less " threshold that the
EPA requires. Tightness Class CM, for
example, can mean that a valve can leak
more than 100 ppm methane, but less
than 500 ppm methane.
In addition, the ISO 15848-1 standard
states that there is no correlation intended
between tightness classes when the
test fluid is helium (classes AH, BH and
CH) and when the test fluid is methane.
In part, this is because the data collected
is different depending on which fluid is
used. For helium, ISO reports the results
as the leak rate proportional to the stem
diameter in atmospheric cubic centimeters
per second (atm cm3
/sec). Since it
is not reported in the more traditional
" ppm " metric, this makes it difficult to
determine whether the valves comply
with the EPA's " 100 ppm or less " standard
if helium is used. Unfortunately, it
is impossible to convert atm cm3
/sec to
ppm because no formula exists.
Finally, third-party laboratories should
conduct the tests, instead of the valve
manufacturers themselves. Plant operators
can feel confident that tests handled
by independent third parties are not biased
in any way. Therefore, manufacturers
should provide valve certifications that include
a seal from the third-party lab, along
with the testing location and the results.
Get ahead of emissions requirements.
Valves that are certified as " lowE "
are ideal to reduce fugitive emissions,
whether they are being specified for a
new system or being added to enhance an
LDAR program. Installing low-E valves
before the EPA finds high fugitive emissions
levels can save processing plants significant
money in the long run by avoiding
costly refits (FIG. 2). The valves also allow
facilities to remain compliant with current
environmental best practices. Therefore,
it is helpful to ensure that plant personnel
know which valves to order for low-VOC
service, so that the plant can maintain
operational and environmental integrity.
When assistance is needed in determining
what low-E solutions might work best for
specific applications, it is best to consult
with an experienced fluid system specialist
to secure third-party-tested solutions
that will keep the facility in compliance.
SEAN HUNSICKER is a Market Manager for Swagelok.
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intelligence for the
gas processing
industry
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covers the latest advances and trends in
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HP March 2022 eBook—Energy Transition

Table of Contents for the Digital Edition of HP March 2022 eBook—Energy Transition

Contents
HP March 2022 eBook—Energy Transition - Cover1
HP March 2022 eBook—Energy Transition - Cover2
HP March 2022 eBook—Energy Transition - 3
HP March 2022 eBook—Energy Transition - Contents
HP March 2022 eBook—Energy Transition - 5
HP March 2022 eBook—Energy Transition - 6
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HP March 2022 eBook—Energy Transition - Cover3
HP March 2022 eBook—Energy Transition - Cover4
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https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018
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