The Role of the Insulation System in Optimizing value in LNG Facilities

1. REPRINTED FROM JUL/AUG 2015 LNGINDUSTRY
T
he rising cost of LNG facility construction and the future volatility
of natural gas prices are motivating stakeholders to pay even more
attention to optimising value while mitigating investment risks.
Concerns dictate a second or even third look at optimising lifecycle risk and
performance – steps beyond lifecycle cost. This article will consider the
role of the insulation system in these efforts, since it has a material impact
not only on lifecycle cost (material/labour capital cost, as well as long-term
operation/maintenance costs), but also on lifecycle performance and risk.
Ted
Berglund
and Joe Hughes,
Dyplast Products, USA,
examine the role of the insulation
system in optimising value in LNG facilities.
Mission critical
critical

2. LNGINDUSTRY REPRINTED FROM JUL/AUG 2015
Some key risks include:
 Engineering, procurement and construction (EPC)
schedule delays.
 Operational energy/process inefficiencies.
 Outage/curtailments.
 Poor system resilience (e.g. from incidents, extreme
weather events).
 Low margins of error.
 Inflexibility (e.g. in process modifications, more cycling
and expansion).
While the CAPEX of the insulation system is relatively
small compared to the rest of the facility, it is substantive; and
the additional impacts an insulant can have on the
aforementioned parameters make the insulation system
‘mission critical’. For example, credible yet subjective analysis
indicates that approximately half of delays to LNG facility
completion dates are attributable to construction schedules
that do not allocate sufficient time for a quality installation of
the insulation system. Moreover, on average, the cost of an
insulation failure results in ~US$100 000 for each occurrence,
and sometimes more impact on operating costs (curtailment
of production, and repair material/labour).
Insulant selection
Basic impact on the insulation system
All LNG facilities need insulation on piping, tanks,
and equipment. A typical large LNG facility may have
30 000 − 50 000 or more linear ft of piping with diameters
ranging from 1 − 24 in., sometimes larger. Consider a sample
of 100 linear ft of 20 in. dia. LNG pipe. Depending on the
insulant selected, the following parameters apply:
 The insulant can range from <5000 to >8000 board ft (a
60% differential).
 Capital cost of the insulants (in required thickness, and
ignoring amounts of vapour barriers, jackets, etc.) can vary
by >200%.
 Installed cost of the insulation system can vary by
~300%.
 Weight of the insulants can vary by 600%. With the
heavier insulants, this is approximately 70% of the
weight per ft of a 20 in. pipe (0.365 in. wall), resulting in
increased structural support cost.
Note
There is virtually no correlation between cost per board ft and
thermal resistance, and in some cases, an inverse correlation
exists. Similarly, a higher weight insulant may or may not
have better thermal resistance, yet can be assumed to add to
the cost of the installation.
Stakeholders are increasingly insisting on objective
answers as to why more money is often paid for poorer
thermal performance simply because an insulant ‘is specified.’
Due diligence
When insulation design engineers select an LNG insulant on
behalf of their client, their selection fundamentally dictates
the design/cost/risk/labour profile associated with the entire
insulation system. Each insulant requires different approaches
to vapour barriers, expansion joints, accommodations for the
overall weight of the system with stress on pipe hangers,
as well as installation procedures, long-term maintenance,
etc. Additionally, there are new approaches to LNG system
design, including modularisation and pre-insulation of pipe
before shipment. Some designers have not yet considered the
impacts on the insulation systems necessary to support new
LNG design approaches. Examples include shear key systems
for module interconnection, pre-insulation of modules prior to
shipping to the site, and factory-applied vapour retarders when
contractor installation guides only address field-applied.
Insulation system designers generally start with two initial
choices: select the insulant that was previously qualified by
the organisation or consider requalification of the old and/or
qualification of newcomers in light of what is known today.
The periodic requalification is important due to a number
of factors, including changes in the following:
 Specification standards (e.g. ASTM, CINI).
 Chemical formulation (such as the chemical’s molecular
components, or changes in additives such as fire
retardants, catalysts, etc.).
 Manufacturing methodologies.
 Manufacturing locations.
Figure 2. Dyplast polyiso with vapour stop at Elba Island.
Figure 1. Elba Island LNG facility.

3. REPRINTED FROM JUL/AUG 2015 LNGINDUSTRY
In the latter case, for instance, an insulant manufacturing
facility may relocate the insulation manufacturing to the LNG
equipment assembly site in order to be more responsive/cost
effective. However, most product certification entities,
including Factory Mutual (FM) and Underwriters Laboratories
(UL), require physical properties from each location of
manufacture to be tested in order to remain certified. This
ensures the product delivered is the same as the product
specified. In all cases, due diligence is paramount. The
process of due diligence and selection of insulants is
multifaceted; this article will examine a few of the
components of due diligence that sometimes escape decision
makers/influencers.
Lifecycle performance/risk
It is not possible to fully discuss lifecycle performance/risk
in detail in this article. However, the insulant selection stage
is a critical step in the process. Being better informed means
mitigating risks and potentially improving performance. To be
better informed, the following must be understood:
 What information is pertinent?
 What information is factual?
 Is there full disclosure of all pertinent facts?
In other words, ‘better informed’ does not simply mean
more information.
What information is pertinent?
When considering what is pertinent there is the ‘must have’
of thermal conductivity (K-factor or lambda) − the lower the
better. At the top of the list are:
 The temperature at which K-factor is measured.
 Initial vs aged (clearly defined by ASTM and other
standards). For instance, ‘cured’ or ‘fresh’ have no
meaning within any credible standard.
 Water vapour transmission (WVT) and water absorption
(WA).
 Other, depending on circumstance.
Temperature vs K-factor
The testing standards/protocols appear to be increasingly
focused on K-factors across a variety of temperatures, whereas
the traditional approach had been to compare insulants at
approximately 70 − 75°F. The newest ASTM C591 standard (the
overall standard to which polyisocyanurate [polyiso or PIR]
must comply) now requires K-factors to be measured across
multiple temperatures from -200°F to +200°F. Taking into
account the fact that the K-factor of most insulants improves
at lower temperatures, thickness calculation programmes,
such as 3E-Plus, now incorporate a range of K-factors vs
temperature for each insulant.
Thermal ageing
Thermal ageing represents the process by which insulants using
blowing agents such as hydrocarbons (not air) lose some of their
thermal resistance over time, as some blowing agents diffuse
out of the cells. ASTM testing protocols involve ageing these
insulants for six months in a controlled environment, intending
to anticipate the actual thermal conductivity over the life of the
insulant. The aged K-factors of some prevalent insulants are
still better than the initial K-factors of insulants that purportedly
do not age. Moreover, thermal ageing slows down at lower
temperatures, and at cryogenic temperatures ageing can be
assumed as nil or at least considerably reduced.
WVT/WA
The other major pertinent property of insulants is WVT and WA.
It is important to prevent water vapour reaching the piping.
Additionally, any water absorbed into an insulant worsens its
K-factor (reducing thermal resistance). If a vapour barrier (meaning
zero-permeability) sheet or mastic is applied over the insulation,
the WVT and the WA of the system should each be zero.
However, in a conservatively designed insulation system (which
all LNG installations should be), the designer must consider both
errors in application of vapour barriers and/or breach of the barrier,
which can be caused by several factors. Thus, a second line of
Figure 3. Dyplast ISO-C1 on the Elba Island LNG insulation
systems.
Figure 4. Dyplast polyiso bunstock production.

4. LNGINDUSTRY REPRINTED FROM JUL/AUG 2015
defense is an advantage, i.e. the insulant itself, exclusive of any
vapour barrier, should have low permeability.
Other
Beyond these primary physical properties, others can be
important. Higher compressive strength, for example,
is important when mechanical abuse is likely, and in
circumstances where insulants carry load within pipe hangers.
Flame/smoke ratings can be important, however some
engineers conclude a metal jacket virtually eliminates flame
spread caused by insulation; and in case of a fire at an LNG
plant, most engineers agree that smoking insulation is the
last thing to worry about. Dimensional stability, weight, and
flexural strength also have an impact on insulation system
design and must be appropriately integrated by a qualified
engineer.
Noting CINI as a dominant standard in many LNG plants,
there is also the CINI Cryogenic Thermal Stress Resistance
(CTSR) factor.
What information is factual?
At the top of the list for consideration by evaluating engineers is
third party testing of physical properties. This is followed closely
by listed approvals supported by a periodic third party audit by a
reputable entity, such as FM, UL, International Code Council (ICC),
or other. Too often, manufacturers and suppliers quote physical
properties measured within their own laboratories, using sampling
and testing protocols that may not comply with industry standards
(e.g. ASTM and CINI, etc.). These protocols include the following:
 Sample curing/ageing.
 Parallel vs perpendicular cut samples.
 Sample selection (middle of sample, edge of sample,
skins removed, an average, etc.).
 Equipment calibration.
 Date of last test, and whether formulations or regulations
have changed since the last test.
Regarding the first three protocols, it is possible to bias a test
by testing samples that may not be representative of the product
being sold. The chemical formulation of an insulant, for example,
can be tweaked specifically for a test sample to yield improved
thermal conductivity or strength measurements, while
compromising other properties such as flame/smoke. This is
why third party audit adds additional assurances. In the absence
of third party audit, the engineer/end user should, at a minimum,
ask relevant questions and insist on contractual representations
from the seller of the insulant’s properties.
With respect to the final protocol, the date of the test is
critical. Testing reports must reflect the current products being
offered. Credible authorities require re-testing when insulant
formulations or methods of manufacturing change. Even minor
adjustments to blowing agents, flame retardants, catalysts, etc.
will alter physical and fire performance properties. A good
example is the recent withdrawal from the market of a common
polyol used in polyiso insulants, requiring manufacturers to
switch to alternative polyol molecules. Proper selection of the
replacement polyol can improve performance; poor due
diligence in selection can degrade it. Decision makers should
enquire about any changes to inputs or manufacturing
procedures that should justify product re-testing.
A final consideration is that ASTM, CINI, and other
standards/protocols often make ‘like to like’ comparisons
challenging, and requisite codes may not reflect rapidly changing
regulatory and technology environments. This can result in either
far too lenient standards, or at the other extreme, unachievable
standards. A case in point is the variation in WA tests defined by
ASTM for different insulants, which vary from 24 − 96 hr. Other
tests sometimes differ in their specifying percentage based on
weight, while others specify percentage based on volume. The
specifying engineer should clearly understand the essence of
each testing protocol and should verify the pertinence and the
facts. Using the WA example, assuming ≤1% WA is the
specification, why is it pertinent without specifying per weight or
per volume, and what if a 1% moisture gain in one insulant may
materially impact K-factor while it may not in another?
Is there full disclosure of all relevant facts?
With respect to full disclosure, insulation suppliers and
manufacturers often do not expose key physical properties
that could be perceived as negative. As mentioned earlier,
this could be the aged K-factor, the parallel strength vs the
perpendicular, the dimensional stability (volume vs length)
at low temperature, the actual WA or WVT of the insulant
itself without the skin or the laminate, flexibility at low
temperatures, cost per board ft, delivery times/flexibilities,
prior successes and failures (plus root causes), etc.
Stakeholders should insist upon full disclosure, or at least
disclosure comparable to competing suppliers. Insistence
on conformance with ASTM or CINI standards for cryogenic
applications and requisite compliance mitigates these issues.
Case study: Elba Island
Elba Island, an LNG facility off the coast of South Carolina, US,
selected polyisocyanurate manufactured by Dyplast Products
as the core of its insulation system. ISO-C1®
was selected
after multi-value assessments by the turnkey EPC contractor
and the client. Key factors in the decision included the
following:
 Physical properties audited and validated by an
independent laboratory.
 Physical properties of ISO-C1 met or exceeded
requirements set by ASTM C591.
 ISO-C1 exhibited the low aged K-factor – this allowed
a total insulant thickness of only 7.5 in. on a 20 in. pipe,
compared to the 10 in. required if cellular glass was used.
 ISO-C1’s K-factor improved significantly as temperatures
dropped.
 The density of ISO-C1 at 2 lb/ft3
made handling and
shipping easier than 7.5 lb/ft3
cellular glass. Structural
engineers were able to minimise the number of pipe
supports, reducing cost.
 Customised bunstock sizing provided efficient shipping
logistics and scrap minimisation during fabrication.
 Availability of higher density polyiso (up to 6 lb/ft3
)
provided the higher compressive strengths to support pipe
hanger applications.
 Ability to fabricate blocks to close tolerances allowed for
tight seams and joints.

5.  Flexibility and responsiveness in deliveries and technical
advice enabled reduced costs, improved schedules, and
enhanced relationships.
 Easy to handle and work in the field, with minimal
breakage.
 Quick product turnaround and delivery (e.g. 2 − 3 days).
Dyplast’s scope of work included polyiso insulation for
31 895 linear ft of piping that connects the ship offloading
facilities with storage, regasification and transportation facilities.
The insulation system consisted of double-layer insulation for
piping with outside diameters varying in size from 3.5 − 41.25 in.,
covered with a combination of vapour barrier sheeting and
mastic, enveloped in aluminium colour-coded jacketing.
Specifications required stringent adherence to validated physical
properties for insulation system components, as well as specific
standards for shop fabrication of shaped insulation segments,
such as dimensional tolerances for hemicylindrical sections, pipe
ells for small elbows, mitered sections for large elbows, and
tees.
The ability to customise polyiso bunstock dimensions was
an advantage, since bun sizes could be matched to minimise
waste as Dyplast cut the bunstock into blocks (‘pipe chunks’),
which were, in turn, sized for minimising waste during shape
fabrication. Optimally sized pipe chunks also allowed for
efficient packing in transportation containers. The company
shipped over 1.25 million board ft of ISO-C1 in 43 semi-trailers
to support the construction schedule.
The project schedule could be met only if parallel
construction work was effectively executed and coordinated so
that schedule savings could be realised at every opportunity.
Dyplast’s flexible delivery schedule and ability to execute
just-in-time deliveries were advantageous. Communication
feedback from the company ensured that installation of the
insulation system proceeded efficiently and in sync with other
contractors.
Conclusion
Natural gas markets remain unpredictable. Markets have
increasingly regional dynamics, and LNG construction costs
rise. Selection of the optimal insulant supported by its
appropriate insulation system becomes ‘mission critical’.
Engineers, specifiers, owners, and stakeholders should be
increasingly vigilant regarding the facts, the relevance of the
facts, and full disclosure as validated by independent parties.
Specifications, standards, regulations, and technologies
change. Insulant manufacturers either adapt to comply
with the latest standards in order to support their client’s
objectives, or they choose to be parochial in advancement of
short-term interests. Ultimately, it is up to the owner or the
investor to ask the tougher questions, or to ensure that their
engineers are.