JEC COMPOSITES MAGAZINE - Issue #88 - April 2014 - Special JEC Americas Spring Edition - 16

industry

about 3 hours. The fire shelters are
available with ratings of 30, 60, 90
and 120 minutes.

Fig. 2: The low weight of Intertec's fire-resistant composite materials allows fire shelters to be mounted directly onto
pipework

ties for as long as possible, and
degrades in a slow and predictable
manner.
GRP is inherently inert and unaffected by corrosion, making it a
better alternative to metal in many
field equipment containment
applications, especially those that
demand a long lifecycle under
hostile environmental conditions.
It has a similar strength to stainless
steel, but weighs 75% less - an
important consideration on offshore platforms, where the weight
of the shelter and its supporting
structure is a cost factor.
In the case of fire shelters, composite materials also provide much
longer protection times. While it
may seem paradoxical that enclosures constructed from a material

incorporating GRP can be more
fire resistant than those fabricated from metal, the key factor is
thermal conductivity. Steel, for
example, has a very high thermal
conductivity (λ ≈ 15-50 W/m.K),
which means that in the event
of a fire, heat is readily conducted through the shelter's walls
to its inside, so the permissible
temperature (such as ambient +
180 K) is reached too quickly. If
the internal wall becomes too hot,
it is likely that other materials will
catch fire and the function of the
fire wall will have failed.
GRP, on the other hand, has a
much lower thermal conductivity
(λ ≈ 0.2 W/m.K), so shelters
that use this material to sandwich
layers of fire-resistant mineral
wool conduct heat much more
slowly.

16 jec composites magazine / No88 April 2014

Verifying performance
At present, there are no specific
international standards for this
application area, so Intertec has
defined its own test procedure
and conditions. The shelter is
placed in an oven that is heated to
a specific time-temperature curve,
while the equipment inside the
shelter is monitored to check that
it is kept below its operational
temperature (usually 60°C). The
company's standard fire shelters
are tested to the type of nominal
time-temperature curves defined
in ISO 834, which is used in
many fire protection standards
and characterises the type of slow
burning fires that can occur in
residential and commercial buildings. These typically take about
30 minutes to reach 800°C, attaining a maximum of 1,100°C after

For applications where there
is a risk of more severe fires,
Intertec produces the 1709
fire shelter that can withstand
hydrocarbon jet or pool fires,
which can reach 1093°C within
the first five minutes. This form
of fire shelter is tested against the
rapid temperature rise fire curve
used in ANSI/UL 1709 which,
in the absence of more specific
standards, is employed by many
process plant designers when
stipulating fire-resistant materials.
However, because the standard
is aimed at protecting structural
steel in buildings, it assumes a
permissible temperature of 540°C
(steel does not lose its integrity
below this level), whereas the
1709 fire shelter is designed to
keep valves and actuators fully
operational, i.e., below 60°C for
the entire duration of its specified
protection time.
The 1709 design has been tested
by an independent agency, which
verified that the surface temperature of a sample electrical actuator
contained within the shelter
remained below 60°C throughout
a 90-minute test involving a
simulated hydrocarbon fire. This
level of protection is believed to
be unique for passive fire shelters.
Furthermore, the manufacturing
method is suitable for producing large panels of fire-resistant
composite material - opening up
number of new application areas
such as the construction of gastight fire-resistant walls to separate
hazardous and non-hazardous
areas to meet improved regulatory
standards. n
More information:
www.intertec.info

http://www.intertec.info

JEC COMPOSITES MAGAZINE - Issue #88 - April 2014 - Special JEC Americas Spring Edition

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #88 - April 2014 - Special JEC Americas Spring Edition