technical NOTES

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4. Aluminization with Heat Resistant Painting


Aluminization is done in the cement industry for heat savings and corrosion
protections in preheater cyclones and other critical equipment’s and is most widely
used. Though few companies have initiated Heat Resistant Painting instead of
Aluminization due to its similar temperature reduction properties but the guaranteed
skin temperature reduction is higher in case of Aluminization i.e. 10-15 % internal
surface & external surfaces as compared to Heat Resistant paints with 10 % on each
side. Generally, the heat resistance paint gives life for 6-8 months only whereas
Aluminization life is more than 5 years.
Aluminization
Aluminum wire is infused with mild steel plate, it is pure metal coating of molten
particle on surface which absorb heat and reduces the radiation losses by retaining
the heat. Dry film thickness is around 200 -225 microns in Aluminization against 75
-100 microns in HR paints. The additional DFT shall give better anticorrosive properties.
Thermal Spray coating of Aluminizing protects steel surfaces against atmospheric
corrosion and oxidation at elevated temperature, it absorbs heat and reduces heat
radiation.
Special Heat Resistant Paints:
It is developed by few paint manufacturers, film thickness is lesser so decay in this
thickness over the period of time will increase and effective ness of heat resistant
properties & savings may reduce.
Heat Resistant Painting is a high build single component silicon co-polymer resin
matrix incorporating insulating, blocking and reflecting agents to reduce heat transfer,
it also helps in reducing condensation formation. Microscopic air filled ceramic
particles blended with premium silicon co-polymer resins provide substantial
temperature differential in relatively thin film thickness of around 75-100 micron.
We have taken the performance feedback of Aluminization and HR Paintings from
the reference plants and the performances are observed more satisfactory in
Aluminization.


Conclusion
Thereby, we recommend Aluminization over heat resistant paint which is
economical due to its higher life and aesthetic look of plant remains for
longer period.


S. N. Application Cost INR/ SQM

1
Supply and application cost of heat resistant
paint

597

2
Supply and application cost of Aluminization
paint

960
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