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Corrosion Protection
Biological Control
Chemical Treatments
Passivation
Long Term Care of Stainless
Steel
BAC’s Manufacturing Process
Recommended Cleaning
Procedure
Long Term Care of Stainless Steel
Whenthepercentageofchromiuminsteelexceeds10.5%,itiscalledstainlesssteel.The
chromiuminthesteelreactswiththeoxygenintheairtoformachromium-oxidesurface
layer,alsocalledthepassivationlayerthatprovidesthecorrosionresistanceinstainless
steel.
BAC’s Manufacturing Process
BACtakesprecautionstopreventcross-contamination,processinggalvanizedandstainless
steelpartsseparately.Also,stainlesssteelbrushesareusedtocleanweldsonstainless
partsandcareistakentoavoidscratchingpartsduringprocessing.Organiccleanersare
usedtocleanthenishedproductpriortoshipping.
Jobsite Considerations
Whilestainlesssteelitselfdoesnotrustsolongasthechromium-oxidesurfacelayeris
intact,itisnotimmunetocontaminationfromitssurroundings.Somecommonsourcesof
surfacecontaminationare:
• Dirtandsoil
• Shopoilorgreasethatmaycarryothercontaminantssuchasmetalchips
• Machiningorweldinggalvanizedsteelatthejobsitemaycausedebristoimpingeitself
intothestainlesssteel
Thesecontaminantscandepositonthesurfaceandscratchthepassivationlayerorprevent
itfromre-forming.Theycanalsogettrappedunderneaththepassivationlayerandreduce
corrosionresistance.
Recommended Cleaning Procedure
Stainlesssteelneedstobecleanedregularlytomaintainthecorrosionresistanceaswellas
tomaintaintheoverallaestheticsofthestainlesssteel.
Itisfairlysimpletocleanmostcontaminantsoffthesurfaceofstainlesssteel.Mostdirt
andsoilcanbecleanedwithacleancloth,warmwater,andmilddetergent.Forpersistent
dirt,alittlevinegarcanbeaddedinthecleaningwater.Itisimportanttoalwaysrinse
thesurfacewithwarmwaterandwipewithadryclothafteranycleaning,whethermildor
aggressive.
• Fingerprints,mildstainsorgreasespotscanbecleanedusingorganicsolventssuch
asacetone,methylorethylalcohol,ormineralspirits.Stainlesssteelwipesorglass
cleanerscommonlyavailableinstoresmayalsobeused.
• Occasionallythesurfaceofstainlesssteelcangetironchipsorshavingsembedded
initfromhavinggalvanizedsteelmachinedorweldedinthevicinity.Theironchips
canstarttorust,reducingthecorrosionresistanceofthestainlesssteel,andstain
thesurfacegivingtheimpressionthatthestainlesssteelisrusting.Thesetypesof
contaminantsrequiremoreaggressivecleaning.MildabrasivessuchasScotch-Brite™
productsmaybeusedwhereaestheticconsiderationsarenotimportantfollowedby
solventcleaningwithorganicsolventsasdescribedabove.Itisimportanttorinsethe
surfacewithwarmwaterandwipewithadryclothaftercleaning.
• IftheironchipsarenotremovedwiththeScotch-Brite™Products,electro-chemical
cleaningmayberequired.BACusescommerciallyavailableequipmentforelectro-
chemicalcleaningintheeld.ContactyourlocalBACRepresentativeformore
informationortoarrangeaservicecall.
ATTENTION: 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.