— 15 —
C24EO SERIES STEAMER
STAINLESS STEEL EQUIPMENT CARE
AND CLEANING
Contrary to popular belief, stainless steels
ARE susceptible to rusting.
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, containing
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 to 30% 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 stainless. If the passive fi lm of
stainless steel has been broken, equipment
starts to corrode and starts to rust.
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 leaves 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
cleaning 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.