BAC 3240C - Long Term Care of Stainless Steel

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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
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nished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galvanizedsteel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.
Recommended Cleaning Procedure
Stainlesssteelneedstobecleanedregularlytomaintainthecorrosionresistanceaswellas
tomaintaintheoverallaestheticsofthestainlesssteel.
Itisfairlysimpletocleanmostcontaminantsoffthesurfaceofstainlesssteel.Mostdirt
andsoilcanbecleanedwithacleancloth,warmwater,andmilddetergent.Forpersistent
dirt,alittlevinegarcanbeaddedinthecleaningwater.Itisimportanttoalwaysrinse
thesurfacewithwarmwaterandwipewithadryclothafteranycleaning,whethermildor
aggressive.
• Fingerprints,mildstainsorgreasespotscanbecleanedusingorganicsolventssuch
asacetone,methylorethylalcohol,ormineralspirits.Stainlesssteelwipesorglass
cleanerscommonlyavailableinstoresmayalsobeused.
• Occasionallythesurfaceofstainlesssteelcangetironchipsorshavingsembedded
initfromhavinggalvanizedsteelmachinedorweldedinthevicinity.Theironchips
canstarttorust,reducingthecorrosionresistanceofthestainlesssteel,andstain
thesurfacegivingtheimpressionthatthestainlesssteelisrusting.Thesetypesof
contaminantsrequiremoreaggressivecleaning.MildabrasivessuchasScotch-Brite™
productsmaybeusedwhereaestheticconsiderationsarenotimportantfollowedby
solventcleaningwithorganicsolventsasdescribedabove.Itisimportanttorinsethe
surfacewithwarmwaterandwipewithadryclothaftercleaning.
• IftheironchipsarenotremovedwiththeScotch-Brite™Products,electro-chemical
cleaningmayberequired.BACusescommerciallyavailableequipmentforelectro-
chemicalcleaningintheeld.ContactyourlocalBACRepresentativeformore
informationortoarrangeaservicecall.
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.