Roxul Industrial Insulation Process - Manual (Page 73)

1.6 Insulation of boilers
1.6.2 Supercritical steam generators
Handles
Handles are reinforcement elements, which are
fitted vertically between the buckstays (girders)
and bear the vertical loads exerted on the
buckstays on the boiler wall. Handles can be
located inside and outside the insulation sections.
Installation of the insulation system for
utility steam generators
The following product characteristics are
important when selecting a suitable insulation
system for utility steam generators:
The insulations used must be non combustible.
The maximum service temperature of the
insulation must be higher than the operating
temperature of the installation component to be
insulated.
The thermal conductivity must be specified as a
function of the temperature.
The (longitudinal) air flow resistance must be as
high as possible. High flow resistances reduce
convection in the insulation.
In addition to protection against contact and the
maximum permissible surface temperatures of
140 °F (60 °C), industrial parameters such as
efficiency factors must be considered during the
design of the insulation thickness. The AGI
guideline Q101‚ “Insulation works on power plant
components” recommends that the insulation
layer thicknesses for power plant components is
designed for a maximum heat flow rate density of
47.5 BTU/hr.ft
2 (150 W/m 2 ). In view of rising energy
prices and CO²-emission reductions, this
generally recommended value is, however, subject
to critical analysis. From an economic and
environmental perspective, a design parameter of
well below 47.5 BTU/hr.ft
2 (150 W/m 2 ) is often
sensible. ProRox ® insulation have proven
invaluable in the insulation of utility steam
generators over the years. They are flexible and
can be easily mounted onto the various
geometries or surface structures. ProRox
®
insulation products are non combustible, have
high maximum service temperatures and exhibit a
low degree of thermal conductivity across the
entire temperature range.
The insulation is assembled in multiple layers,
comprising two to three layers of insulation.
ProRox
® insulation with a maximum service
temperature of 1200 °F (650 °C) are a tried and
tested solution as a first insulating layer in upper
1. Boiler roof - 2. Dead space - 3. Cross bar - 4.
Collector - 5. Boiler support tube - 6. Boiler wall -
7. Buckstay - 8. Handles - 9. Burner port - 10. Boiler
funnel
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