Roxul Industrial Insulation Process - Manual (Page 22)

Planning and pr
epar
ation
1.1 Planning and preparation
1.1.2 Design & planning of the
insulation work
Requirements for insulation work must be
included in the design and construction phase of
industrial plants. It is advisable to involve all
project managers at an early stage to avoid
unnecessary issues or delays.
All preparatory works must be completed
according to the relevant insulation standards.
The following preconditions must be fulfilled:
If necessary, work has been carried out on the
object to protect against corrosion
Tracing and technical measurement equipment
have been installed
The minimum distance between the objects
has been observed (see illustrations on pages
12 and 13)
Surfaces have no coarse impurities
Mounting supports have been installed on the
object to accommodate the support structure
Collars and sealing discs have been fitted to
the object
Taps on the object are long enough to ensure
that flanges lie outside the insulation and can
be screwed on without hindrance
Supports are designed so that insulation,
water vapor retarders and cladding can be
professionally installed
The insulation can be applied without any
obstacles (e.g. scaffolding)
Welding and bonding work has been carried out
on the object
The foundations have been completed
1.1.3 Corrosion prevention
Industrial facility disruptions are due to the lack
of, or inadequate forms of, protection against
corrosion. This considerably reduces the service
life of industrial plants, and more frequently,
essential shutdown or overhaul work impairs the
efficiency of the installation.
It is commonly, but wrongly, assumed that the
insulation system also protects an installation
against corrosion. For each installation it must be
determined whether protection against corrosion
is required and, if so, which are the appropriate
measures.
Generally, the design of the insulation system &
corrosion protection will depend on the following
parameters.
Operation of the installation
- Continuous operation
- Interrupted/intermittent operation
- Operation involving varying temperatures
- Type of plant (e.g. Petrochemical,
pharmaceutical,
etc)
Operating and Ambient temperatures of the
installation
Metals and Materials Used
- Non-alloy or low-alloy steel
- Austenitic stainless steel
- Copper
External influences upon the installation
- Environment of the installation (chemically
aggressive?)
- Location
The best practices may vary per country and/or
standard. The design of corrosion protection is
often carried out on the basis of a small selection
of standards, such as ASTM C795, that do not
adequately take into account all the specific
features of protecting against corrosion in
insulation systems. For further details on
corrosion protection we recommend referring
NACE SP0198 and the RoXUL
® Corrosion Under
Insulation (CUI) brochure.
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