Roxul Industrial Insulation Process - Manual (Page 18)

Planning and pr
epar
ation
e) Frost protection
Installations that are situated outside are at risk
from frost in the winter. In addition to the
malfunctioning of installations, installations also
risk damage caused by the expansion of frozen
water. Adequate measures against frost protection
are critical to protect the installation from
freezing. Insulation can reduce heat loss and aid
in frost protection. Insulation alone cannot
indefinitely prevent the installation from freezing.
Installing additional tracing may be necessary
between the object and the insulation. To prevent
freezing, the insulation must be designed so the
heat flow rate of the insulated object is less than
the heat provided by the tracing.
f) Ambient conditions
Select an insulation system that offers long-lasting
resistance to the surrounding environme nt.
Atmospheric influences: wind, rain
Mechanical loads such as vibrations or
foot traffic
Corrosive environment (proximity to sea,
chemicals,…)
Moisture accumulation in insulation increases
thermal conductivity and the risk of corrosion of
the insulated installation components. Cladding
must be installed to prevent the ingress of
moisture into the system. If the ingress of
moisture into the insulation is unavoidable, retain
an air space of at least 2/3” (15 mm) between the
insulation and the cladding, and create 0.4”
(10 mm) diameter ventilation and drain holes in
the covering at intervals at a maximum of 12"
(300 mm). If necessary, the insulation and
cladding must resist chemical influences that
develop within the environment.
Installations operating below ambient
temperatures have a high risk of moisture
condensing from the ambient air inside the
cladding. Use a continuous vapor retarder on
piping operating below ambient temperatures and
seal all joints, surfaces, seams and fittings to
prevent condensation (use of staples is not
recommended).
g) Maintenance and inspection
To avoid complicating routine maintenance and
inspection work unnecessarily, maintenance-
intensive areas must be taken into account,
especially when designing the insulation work.
Removable insulation systems, such as removable
coverings and hoods, could be fitted in such areas,
for example. Easily removable covering systems
are also recommended for flanges and pipe
fittings. These coverings are generally fastened
with quick-release clamps, which can be opened
without special tools.
The insulation of fixtures such as flanges or pipe
fittings must be interrupted at a sufficient
distance to allow installation or dismounting to be
carried out. In this case, take the bolt length at
flange connections into consideration. Any fixtures
in the range of the insulation, including the
interruption in the installation, should be
insulated with removable coverings overlapping
the insulation and maintaining continuity across
the fixture.
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