The Equipment Design Process
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the insulation system, and chloride stress corrosion cracking of austenitic stainless alloys of piping or component can occur.
The use of a sodium silicate inhibitor in the insulation or the
coating of the stainless steel is discussed in the section on design
requirements. To reduce the invasion of the chloride ion, jacket and
joint seals must be carefully applied. This is discussed in more detail
in the section on jackets with a selection table.
To minimize chloride invasion, the mechanical durability must be
considered in traffic areas on insulation jackets, vibration, or situations of mechanical and thermal shock. Materials of high compressive
strength are the first choice where vehicle damage or foot traffic can be
anticipated. Top heads of vessels with agitators require consideration.
TabLE 11.2
Selection Table for a Thermal Insulation System
Select temperature
range for process
(or tracing)
Identify materials
suitable for this
temperature range
Are chemical
interactions a
controlling factor?
Is mechanical
durability a
controlling factor?
Select those materials
that resist the chemical
interaction concerned
Select appropriate
insulation and/or
vapor barrier
Select materials with
high compressive
strength
Select materials with
appropriate properties
Are moisture
concerns a
controlling factor?
Are safety
considerations a
controlling factor?
Select lowest cost
materials that suit all
controlling factors
No
No
No
No
Yes
Yes
Yes
Yes