PaintSquare.com
Follow us on Twitter Follow us on LinkedIn Like us on Facebook Follow us on Instagram Visit the TPC Store
Search the site

 

Advertisement

PaintSquare


Problem Solving Forum

| More

September 3 - September 9, 2012

What is the proper surface preparation for stainless steel before coating to resist a salt-laden atmosphere?

More items for Surface Preparation


Selected Answers

From Derek Righinni of Certified Coating Inspection Ltd on September 13, 2012:
     There is no clear consensus on a cleanliness standard that stainless steel is required to meet before the application of coatings to protect it from chloride-induced pitting or stress corrosion cracking. The question is, is the chromium oxide passive layer  that forms rapidly on the surface of SS tightly adherent and suitable for painting?  The answer to the question  dictates the time period allowable between the start of blasting to the maximum time the SS substrate can be left before coating. NACE, SSPC, ISO, ICORR: pull your finger out and give the industry some clear guidance on the preparation of stainless steel for painting with protective coatings and linings.

From William Slama of International Paint/Ceilcote Products on September 10, 2012:
Over the years, there have been many of these applications required where the original alloy was found to be inadequate for the operating conditions (usually chloride fluoride chemistry) of the vessel or equipment. In some cases, this was identified even before being placed in service; other times, when the alloy didfn't perform as expected. A recurring recent case is the many FGD vessels (absorbers and other vessels) constructed of Alloy 2205. Apparently, buildup of scale creates a concentration of chlorides/fluordes under scale buildup, which resusts in extreme pitting of the alloy. The surface preparation, not suprisingly, is not much different than that needed for lining carbon steel. Basically, it requires a clean surface with a sharp profile with the required blast profile (depth) for the system being applied. For most high-build linings or coatings, a 3 mil profile is needed. For most alloys, adjacent unlined surfaces should be protected during abrasive blasting to ensure that it is not contaminated by iron. That is because the most commonly used slag abrasives contain iron. In some cases, that possibility is avoided by using a blast abrasive that does not contain iron. Garnet or aluminum oxide are suitable, providing they are able to produce the required sharp profile. As with carbon steel, the surface must be tested for ion contamination and cleaned if necessary to the lining manufacturer's requirements. One differing feature is that the surface must be coated or primed soon after blasting, unless DH control holds less than 40-50% RH. That is because the surface will not show discoloration of surface oxidation as carbon steel would.

Please sign in to submit your answer this question    

Tagged categories: Salt exposure; Salt-laden air; Stainless steel; Surface preparation


Current PSF Question | Submit a PSF Question | Full PSF Archive

Advertisements
 
Atlantic Design, Inc.
 
CLICK HERE
 
to see what we did to this dust collector! ADI can increase the efficiency and life of your equipment! Any brand, for less than new! 866.Call.ADI
 

 
Montipower, Inc.
 
The MBX Bristle Blaster
 
Get a 2.7 to 3.3 mil profile and a Near White Metal Clean. For info visit www.mbxit.com or call 877 629-8777
 

 
Advanced Recycling Systems
 
ADVANCED RECYCLING SYSTEMS (ARS)
 
Recycling Machines, Dust Collectors, Rapid Deployment units are time-tested and approved for the rugged industrial environment. Contact ARS today!
(330)536-8210
 

 
CHLOR*RID International Inc.
 
SOLUTIONS THAT WORK
 
Companies that invest in corrosion control use CHLOR RID products
  • Soluble salt removal liquid
  • Test kits to verify contamination levels
  • Surface passivation to hold the blast
INFO@CHLOR-RID.COM 800.422.3217
 

 
Clemco Industries Corp.
 
Maximum Dust Suppression Systems Start at $14,950
 
The system comprises proven technology and equipment with user-friendly flexibility in mind. See it in action.
 

 
Novatek Corporation
 
Novatek Corporation, Dustless Coatings Removal
 
Strip, clean and profile all dust free! Comply with new lead standards. Contact today: (866) 563-7800
 

 
Harsco
 
Find BLACK BEAUTY® Abrasives
 
Use our online tool to search by address, city or zip code to find where you can buy BLACK BEAUTY® abrasives. Or call us toll free: 1-888-733-3646
 

 
Abrasives Inc.
 
Need more MAGIC around?
 
Black Magic® is a premier solution for abrasive blast media. Stop by our new website & find out how you can get more Magic. www.AbrasivesInc.com 800-584-7524
 

 
Monti Tools, Inc.
 
BRISTLE BLASTER® – THE ORIGINAL ONE
 
  • Abrasive blast with a power tool
  • Remove corrosion, mill scale and coatings
  • Cleans & roughens
  • Meets SSPC-SP 10 / NACE No. 2
  • Profile up to 4.7 mils
  • ATEX Zone 1
  •  

     
    NLB Corporation
     
    NLB Sure Shroud: Greater Protection and Flexibility
     
    NLB’s Sure Shroud’s lighter weight and flexibility reduces operator fatigue and offers unmatched protection against high pressure hose ruptures. 10k to 40k psi rated.
     

     
     
     

    Technology Publishing Co., 2100 Wharton Street, Suite 310, Pittsburgh PA 15203-1951

    TEL 1-412-431-8300  • FAX  1-412-431-5428  •  EMAIL webmaster@paintsquare.com


    The Technology Publishing Network

    Durability + Design PaintSquare the Journal of Protective Coatings & Linings Paint BidTracker

     
    EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
    REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
    MORE:      About PaintSquare.com   |   Privacy policy   |   Terms & conditions   |   Site Map   |   Search   |   Contact Us