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Corrosion Protection
Chemical Treatment
Requirements
Passivation
Biological Control
Alternative Water Sources
Long Term Care of Stainless
Steel
BAC’s Manufacturing Process
Alternative Water Sources
While make-up water is typically sourced from the potable water system, alternative
sources of water can be considered for use in the Nexus
®
Modular Hybrid Cooler, such
as reclaimed water or air conditioning condensate. Often these sources are blended with
potable water before introducing the water to the unit. The highly corrosion resistant
construction options of the Nexus unit are ideal when using these alternative water sources
due to their tolerance to withstand upset conditions which can occur more frequently with
such sources. Any of the water sources can be utilized as long as the recirculating water
chemistry stays within the limits established in
Table 3
. The risks of using such alternative
water sources, especially regarding biological contamination, need to be recognized and
understood as water quality upsets are often more frequent and the water quality not as
high as potable water only sources. Thus the services of a competent water treatment
professional familiar with treatment programs for such water sources should be engaged.
Long Term Care of Stainless Steel
When the percentage of chromium in steel exceeds 10.5%, it is called stainless steel.
The chromium in the steel reacts with the oxygen in the air to form a chromium-oxide
surface layer, also called the passivation layer that provides the corrosion resistance in
stainless steel.
BAC’s Manufacturing Process
BAC takes precautions to prevent cross-contamination, processing galvanized and stainless
steel parts separately. Also, stainless steel brushes are used to clean welds on stainless
parts and care is taken to avoid scratching parts during processing. Organic cleaners are
used to clean the finished product prior to shipping.
Jobsite Considerations
While stainless steel itself does not rust so long as the chromium-oxide surface layer is
intact, it is not immune to contamination from its surroundings. Some common sources of
surface contamination are:
• Dirt and soil
• Shop oil or grease that may carry other contaminants such as metal chips
• Machining or welding any material at the jobsite may cause debris to impinge itself
into the stainless steel
These contaminants can deposit on the surface and scratch the passivation layer or
prevent it from re-forming. They can also get trapped underneath the passivation layer and
reduce corrosion resistance. Appropriate care in the layout and installation of the Nexus®
Modular Hybrid Cooler should be taken to avoid these potential issues.
NOTICE:
Never use chloride or
chlorine based solvents such as
bleach or muriatic (hydrochloric)
acid to clean stainless steel. It is
important to rinse the surface with
warm water and wipe with a dry
cloth after cleaning.
NOTE:
Long term care of stainless
steel information reprinted with
permission from “The Care and
Cleaning of Stainless Steel”;
Specialty Steel Industry of North
America; http://www.ssina.com.
NOTE:
This passivation process is
not the same as that for galvanized
steel.