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

 

Problem Solving Forum

| More

June 22 - July 6, 2010

I have several water tanks constructed with carbon steel for demineralized water storage. The tanks are about 20 years old, and the original coating has started to blister. For refurbishment of the coating, what material should be used and at what dry film thickness? The original type of coating is unknown.


Selected Answers

From Ted MacMillan of Brant Corrosion Control,Inc. on June 25, 2010:
There are several questions that need to be answered prior to making a proper recommendation for this service, or which path to take with repair of the existing system. If the blistering is extensive, the lining needs to be replaced, if it's minor blistering, chances are the system can be repaired; however, you will have to constantly monitor it during your maintenance program (yearly). Depending on the type of coating system that was applied and the original DFT of the system, you should be able to determine if that particular coating performed the way it was intended to for the service. If the material was a thin film coating, say 10-12 mils, then getting 20 years of life in demineralised water service was a success. If the coating was not maintained regularly, you did exceptionally well. As previously stated by others, demineralised water is very aggressive, and selecting a replacement system should be based on the full operating parameters of the actual service. Our company has installed several systems for these services ranging from thin films to rubber lining. The success of any lining will be dependent on the condition of the existing structure, cleaning to remove contaminants, blast cleaning, application, curing, and final inspection prior to placing the equipment back into service.

From Pieter van der Poel of Danieli Far East on June 23, 2010:
I think you are having a problem with osmotic blistering caused by the demineralized water. Demineralized water tries to absorb minerals, salts, etc., to achieve an equilibrium. This could come from a contaminated substrate sealed by the membrane (this being the existing coating). If the coating has been in service for the last 20 years, it has performed well, especially if localized repairs had been carried out during regular inspection intervals. A coating manufacturer could recommend a lining suitable for the type of service, but wet service temperatures also play an important factor in its selection. Whatever the lining used, it should be impervious to the maximum extent for this type of service. Surface preparation to SSPC-SP 10 and, most important, salt testing should be carried out to avoid future problems with osmotic blistering. The coatings manufacturer will most likely recommend a solvent-free epoxy lining, perhaps even with glass flake. Depending on the extent of blistering, it should be decided whether to go for complete refurbishment as you already stated in your question or to go for spot repairs. Take into consideration any factors related to CP.

From Chuck Pease of MMI Tank on June 23, 2010:
At this time there isn't enough information to answer your question. A couple of things need to occur before a solution can be offered. First question in determining the answer: is the coating you speak of interior or exterior or both? The next thing would be to determine if the existing blistered coating will need to be abated, and more importantly, is it a lead-bearing coating. If the coating is only blistered in various areas but the remainder of the coating is tightly adhered, then one can determine if a surface prep and an overcoat would be appropriate. If the coating is lead-bearing and lossely adhered all around, these factors would suggest complete abatement and prep of steel to SSPC- SP 10 prior to choosing a coating system.

Please sign in to submit your answer this question    


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

NACE International, The Corrosion Society
Get Specialized Coatings Training

Register for courses from NACE’s General Coatings Program to learn how protective coatings and linings are used to control corrosion.


Specialty Products, Inc. (SPI)
Polyurea & Polyurethane Spray Foam Training

SPI is committed to industry leading technical training for polyurea & polyurethane spray foam professionals. Attendees receive hands-on, in-depth training for using and troubleshooting plural-component equipment, spray guns, machine hoses & parts.


DRYCO
Humidity & Temperature Control Equipment

Rental Desiccant Dehumidifiers, ArcticDRY Units, Air Conditioners, Heaters and Generators to help control the climate on your next industrial painting project. Nationwide locations, 24/7 service: (866) 379-2600 www.drycogroup.com”


Safway Services
Safeguard Assets. Ensure Productivity. HAKI®

Protect assets and equipment. Keep facilities open and operational. Maintain schedules regardless of weather. Ensure smooth and continuous production. Easy to erect. Safway is the primary distributor of HAKI® products including HAKISPAN and HAKITEC® 750 – in North America.


Atlantic Design, Inc.
CLICK TO SEE...

what we did to this machine! Let ADI upgrade your machine, extending the life, efficiency, and value. Any make. Like new, but better! 866.Call.ADI


Seymour Midwest
Coating Application Tools & Supplies

Visit our “Where to Buy” site to find a local paint or tool supplier near you. Click here for a chance to win $500 of Tools & Supplies. 1(844)739-6687 Sales@SeymourMidwest.com


Desco Mfg. Co., Inc.
DUST-FREE SOLUTIONS For Lead Abatement

Tools operate at levels well below OSHA limits for hazardous material removal; meet SP11 specifications when required and low vibration tools increase productivity.


US Minerals
US Minerals -
Black Magnum

With nationwide production and distribution capabilities, U.S. Minerals supplies a complete range of coal slag and other abrasives to meet all of your blasting needs.


Absolute Equipment/Grand Rental Station
TIER 4 EQUIPMENT

We have Tier 4 Equipment including Air Compressors & Generators for Sale & Rent! Your job may now require Tier-4. www.absoluteequip.com or Call 412-931-6655.

 
 
 
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