PaintSquare.com
      | Connect Follow us on Twitter Like us on Facebook
About | Subscribe | Advertise
  

 

Free Download of our eBook on Overcoating Bridges and Other Structures

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

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


Monti Tools, Inc.
BRISTLE BLASTER® - THE ORIGINAL ONE

Surface cleanliness of SSPC-10 | Anchor profile
up to 4.7 mils | Removes corrosion & coatings |
ATEX approved for zone 1
| www.monti.com | 832-623-7970


CHLOR*RID International Inc.
Hold*Blast

*Provides outstanding
  performance
*Easy to use and only pennies
  per square foot
*Works with poor quality
  water
*Use for mist blasting, vapor
  blasting, wet blasting and
  UHP WJ
*Leaves no residue and
  provides excellent adhesion.
  www.chlor-rid.com


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


Clemco Industries Corp.
Powerful Protection in a Small Package

Mounts inside blast helmet, alerts operator to dangerous breathing-air condition by audible, visual, and vibratory alarms. Easily calibrated, battery operated.


able equipment rental
RENTALS | SALES | SERVICE | PARTS

Construction equipment, plus compressors up to 1,800 cfm of air power & a fleet of service vehicles providing repairs to customer owned fleets. 866-468-2666.
www.ableequipment.com


Novatek Corporation
Novatek Corporation, Dustless Coatings Removal

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


Atlantic Design, Inc.
BUILDING INNOVATION, NOT IMITATION

The smallest version of our Blast Vacuum Recyclers, this ADI 2300CFM 2-Pot is a cleverly designed power package for those smaller jobs. 866.Call.ADI


N.T. Ruddock Co.

Our Abrasives Hold Up Under Pressure

N. T. Ruddock focuses on abrasive selection, equipment evaluation, equipment maintenance & reduction of abrasive consumption. Other services include Screen Analysis & Background Radiation Testing.


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

The Technology Publishing Network

The Journal of Protective Coatings & Linings (JPCL) PaintSquare
Durability + Design 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
 

© Copyright 2000-2016, Technology Publishing / PaintSquare, All rights reserved
2100 Wharton Street, Suite 310, Pittsburgh PA 15203-1951; Tel 1-412-431-8300; Fax 1-412-431-5428; E-mail webmaster@paintsquare.com