Vulcan-Hart 137716-000BP User Manual

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(Supplied courtesy of NAFEM. For more information, visit their web site at www.nafem.org)

Corrosion on metals is everywhere. It is recognized quickly on iron 
and steel as unsightly yellow/orange rust. Such metals are called 
“active” because they actively corrode in a natural environment when 
their atoms combine with oxygen to form rust.
Stainless steels are passive metals because they contain other 
metals, like chromium, nickel and manganese that stabilize the 
atoms. 400 series stainless steels are called ferritic, contain 
chromium, and are magnetic; 300 series stainless steels are called 
austenitic, contain chromium and nickel; and 200 series stainless, 
also austenitic, contains manganese, nitrogen and carbon. Austenitic 
types of stainless are not magnetic, and generally provide greater 
resistance to corrosion than ferritic types.
With 12-30 percent chromium, an invisible passive fi lm covers the 
steel’s surface acting as a shield against corrosion. As long as the 
fi lm is intact and not broken or contaminated, the metal is passive 
and stain-less. If the passive fi lm of stainless steel has been broken, 
equipment starts to corrode. At its end, it rusts.
Enemies of Stainless Steel

There are three basic things which can break down stainless steel’s 
passivity layer and allow corrosion to occur.

1. Mechanical abrasion
2.  Deposits and water
3. Chlorides

Mechanical abrasion means those things that will scratch a steel 
surface. Steel pads, wire brushes and scrapers are prime examples.
Water comes out of the faucet in varying degrees of hardness. 
Depending on what part of the country you live in, you may have hard 
or soft water. Hard water may leave spots, and when heated leave 
deposits behind that if left to sit, will break down the passive layer and 
rust stainless steel. Other deposits from food preparation and service 
must be properly removed.
Chlorides are found nearly everywhere. They are in water, food 
and table salt. One of the worst chloride perpetrators can come from 
household and industrial cleaners.
So what does all this mean? Don’t Despair!

Here are a few steps that can help prevent stainless steel rust.

1.  Use the proper tools.
When cleaning stainless steel products, use non-abrasive tools. 
Soft cloths and plastic scouring pads will not harm steel’s passive 
layer. Stainless steel pads also can be used but the scrubbing 
motion must be in the direction of the manufacturers’ polishing 
marks.
2.  Clean with the polish lines.
Some stainless steel comes with visible polishing lines or “grain.” 
When visible lines are present, always scrub in a motion parallel 
to the lines. When the grain cannot be seen, play it safe and use 
a soft cloth or plastic scouring pad.
3. Use alkaline, alkaline chlorinated or non-chloride 
containing cleaners.
While many traditional cleaners are loaded with chlorides, the 
industry is providing an ever-increasing choice of non-chloride 
cleaners. If you are not sure of chloride content in the cleaner 
used, contact your cleaner supplier. If your present cleaner 
contains chlorides, ask your supplier if they have an alternative. 
Avoid cleaners containing quaternary salts; it also can attack 
stainless steel and cause pitting and rusting.

4.  Treat your water.
Though this is not always practical, softening hard water can do 
much to reduce deposits. There are certain fi lters that can be 
installed to remove distasteful and corrosive elements. To insure 
proper water treatment, call a treatment specialist.
5.  Keep your food equipment clean.
Use alkaline, alkaline chlorinated or non-chloride cleaners 
at recommended strength. Clean frequently to avoid build-
up of hard, stubborn stains. If you boil water in stainless steel 
equipment, remember the single most likely cause of damage 
is chlorides in the water. Heating cleaners that contain chlorides 
have a similar effect.
6.  Rinse, rinse, rinse.
If chlorinated cleaners are used, rinse and wipe equipment and 
supplies dry immediately. The sooner you wipe off standing water, 
especially when it contains cleaning agents, the better. After 
wiping equipment down, allow it to air dry; oxygen helps maintain 
the stainless steel’s passivity fi lm.
7.  Never use hydrochloric acid (muriatic acid) on stainless 
steel.
8.  Regularly restore/passivate stainless steel.

Routine cleaning

Soap, ammonia, 
detergent, Medallion

Apply with soft 
cloth or sponge.

Fingerprints 
and smears

Arcal 20, Lac-O-
Nu Ecoshine

Provides barrier fi lm

Stubborn stains 
and discoloration

Cameo, Talc, Zud, 
First Impression

Rub in direction 
of polish lines.

Grease and fatty 
acids, blood, 
burnt-on foods

Easy-off, DeGrease 
It Oven Aid

Excellent removal 
on all fi nishes

Grease and Oil

Any good 
commercial 
detergent

Apply with soft 
cloth or sponge.

Restoration/
Passivation

Benefi t, Super 
Sheen

1.  Stainless steels rust when passivity (fi lm-shield) breaks down 
as a result of scrapes, scratches, deposits and chlorides.
2.  Stainless steel rust starts with pits and cracks.
3.  Use the proper tools. Do not use steel pads, wire brushes or 
scrapers to clean stainless steel.
4.  Use non-chlorinated cleaners at recommended concentrations. 
Use only chloride free cleaners.
5. Soften your water. Use fi lters and softeners whenever 
possible.
6. Wipe off cleaning agent(s) and standing water as soon as 
possible. Prolonged contact causes eventual problems.

To learn more about chloride-stress corrosion and how to prevent it, 
contact the equipment manufacturer or cleaning materials supplier.

Developed by Packer Engineering, Naperville, Ill., an independent 
testing laboratory.