May 11, 2015
Got a new tank project upcoming? Want the interior coating of the tank to last a long time? Want it to last a long time without much maintenance, too? You’re able to do this if you’re aware of the AWWA D102 Standard and the Inside Coating Systems within it.
Inside Coating Systems (ICS) are defined in Section 4.4.1 as “coating systems for the inside surfaces of steel water tanks” and refer to the “general type” of coatings but do not “limit acceptable materials to an exact formulation.” As stated in Part I of this series, manufacturers may use the same resin type but are not required to have identical formulas. This allows for resin, pigment, and solvent improvements to be made in coatings intended for the interior tank surfaces. Formulators are allowed enhancements, specifiers are allowed choice, and tank Owners gets a competitive price from multiple suppliers. Everyone wins.
Coatings made with epoxy resins have been used for a long time to protect the interior surfaces of water tanks. These coatings resist water penetration and adhere tenaciously. Inside Coating System No.1 and No.2, representing a two- or three-coat epoxy system, provide 8.0 – 12.0 mils of minimum epoxy protection. Epoxies are also well suited to protect synergistically with water tanks having cathodic protection systems.
Another coating type, used by industry for many years prior to its introduction to the water tank market, are defined as elastomers. These coatings are, and remain, flexible and may be made of components that combine to form polyurea’s, as one example. Polyurea’s cure, and build film thickness, extremely quickly: a perfect combination when your tank needs to go back-in-service today.
Polyurea’s are represented in AWWA D102 as Inside Coating System No.4. At the required minimum 25.0 mils thickness, it may represent the longest-lasting interior coating system currently available.
Want to know more about Long-Lasting Tank Interior Coating Systems?
April 20, 2012
Aqua Pennsylvania, Inc. (Aqua PA) recently needed to recoat the exterior and interior of an elevated wash water tank at their Neshaminy Water Treatment Plant. It was critical that the company, serving more than one million residents in 30 counties across southeastern Pennsylvania, used protective coatings that would deliver a long service life and present a long-lasting attractive appearance to the high visibility tank.
Among the technology used for this project, Opti-Check optically active pigment (OAP) is the star. Used on the poorly lit interiors of water storage tanks, OAP technology can aid in eliminating small defects or bare spots known as holidays, identifying pinholes and reducing premature failures caused by poor film thickness on areas that are difficult to inspect. This type of technology saves companies money because if holidays are found in an inspection (after the inspector waits several days for the paint to dry), then the coating has to be touched up and allowed to dry before it can be inspected again – wasting precious time and money. With OAP, however, inspectors can look for holidays while the coating is still wet.
We recently had the opportunity to tell the story of the Aqua PA project in Water & Wastes Digest. Click here to learn more about OAP technology and how it helped save this customer time and money.
October 26, 2011
Today’s high concentrations of corrosive microbial sulfuric acid can destroy older coating systems such as coal tar epoxy in months, not years. Fortunately, new coatings offer the high corrosion resistance required to protect water and wastewater tanks and pipe. Knowing which coating to choose depends on the specific application.
To learn about these new coatings, join Bruce Snyder for the Sherwin-Williams webinar Extending Life Cycles with New Coating Technologies. An SSPC protective coatings specialist and NACE certified coating inspector, Snyder will discuss:
- Controlling corrosion
- Performance characteristics of several new coating technologies
- Tank rehabilitation techniques
- Common areas of corrosion and how to prevent it
- New coatings for water and wastewater exterior structures, including anti-graffiti
Extending life cycles with new coating technologies
November 8, 2011
12:00 – 1:00PM EST
September 22, 2011
To achieve long-term service life, tank painting requires proper coating selection, application and inspection. Coating systems with Optically Active Pigments (OAP) can help ensure the correct application and inspection of epoxy water tank linings. This technology can help eliminate holidays, identify pinholes, and reduce premature failures caused by poor film thickness on edges, angles or areas that are difficult to inspect.
To learn more about OAP coating systems, tune into the Sherwin-Williams webinar, See What You Get with Optically Active Pigments, hosted by Tony Ippoliti. Ippoliti is an SSPC protective coatings specialist & SSPC instructor, a NACE certified coatings inspector, a Steel Tank Institute and Board of Governors member and instructor, an affiliate member of ASCE and a member of the AWWA D102 revision task group. Ippoliti will share his expert insights on the causes of corrosion in water tanks, edge protection best practices, inspection uniformity and how OAP coating systems can help make the process easier.
See What You Get with Optically Active Pigments
October 18, 2011
12:00 – 1:00 p.m. EST
August 1, 2011
Proper surface preparation readies a surface for good coating adhesion and prevents premature coating failure. When preparing steel and concrete surfaces, certain critical issues must be addressed and standards followed to achieve maximum benefit from today’s high performance, anti-corrosion coatings.
Join Bruce Snyder for the Sherwin-Williams webinar Making the First Step Count – Surface Preparation Standard. An SSPC protective coatings specialist and concrete coating inspector, as well as a NACE certified coating inspector and SSPC CCB/CCI course instructor, Snyder will share SSPC and NACE cleaning standards as well as his expert insights to help ensure surface preparation procedures maximize the coating’s performance characteristics and extend storage tank service life.
Steel preparation standards to be discussed:
- Solvent Cleaning
- Hand Tool Cleaning
- White Metal Blast Cleaning
- Commercial Blast Cleaning
- Near-White Blast Cleaning
- Surface Preparation and Cleaning of Steel and other Hard Materials by High and Ultra High Water Jetting
Making the First Step Count – Surface Preparation Standard
August 9, 2011
12:00 – 1:00PM EST
May 3, 2011
Now more than ever, the sewer collection system is much more vulnerable to corrosive materials that speed the rate of deteroriation. To shed light on the factors that contribute to corrosion in manholes, we were recently featured in the April issue of Trenchless Technology.
The article also provides information on five types of coatings work to prevent corrosion in manholes: cement liners (microsilica mortars and calcium aluminate mortars), epoxy liners (epoxy resin, fiber reinforced and epoxy mortar liners), polyurethane and hybrid polyurea liners and pure polyurea liners.
Check out the article: “The Role of Coatings in Manhole Restoration.”
March 15, 2011
We recently had the opportunity to provide a primer on corrosion and protective coatings in an issue of Water Environment & Technology Magazine (WE&T), the official publication of WEF. Corrosion costs big bucks – the annual cost of metallic corrosion in the U.S. is a whopping $276 billion or 3% of the U.S. gross domestic product. And that $276 billion doesn’t include the cost of aspirin for the headaches that corrosion issues cause owners, specifiers and contractors alike.
The article helps owners understand corrosion of both metallic and concrete substrates so they can better fight it. It details the barriers to corrosion and the types of coatings available to protect assets. Finally, it provides insight on life cycle costs and coatings failure prevention. We think it’s a best practices guide that owners can use to protect their most critical assets for years to come.
Click here to read the full text. To view the article, scroll to the bottom of the page. Unfortunately, the full text of the article is available only to members of the Water Environment Federation (WEF).
August 20, 2010
Sometimes when Sherwin-Williams develops and launches coatings to address specific market needs, down the road we find other markets can benefit from those product attributes. That’s what happened with a rugged glass flake-reinforced amine epoxy coating and lining system that was originally intended for the demanding requirements of the marine and petrochemical markets.
One of our customers, a metropolitan sewerage district, could no longer rely on spot maintenance of its final clarifier’s inner drum and rake arms. Working with our field sales organization, the MSD of Madison, Wisc., learned about a new technology – Sher-Glass – that was prized in petro and marine applications for its low permeability, basically a thin-film system with the same performance as a high-build system.
The glass flake component of the coating, which functions like armor but is lightweight, produces a more cohesive, durable film with enhanced resistance to abrasion and chemicals. Another plus: the superior edge retention so crucial to dealing effectively with the numerous angle welds, edges and seams of a rake arm assembly.
Joe Lynch, senior maintenance supervisor of Madison MSD, had a simple need at the Nine Springs Wastewater Treatment Plant – a long-term approach to asset protection using a durable coating his own people could maintain without specialized plural component equipment or hazmat gear. It’s worked so well that he’s using it again this summer on two additional rake arm assemblies. Read the full story in the current issue of Water & Wastes Digest.
July 27, 2010
Standards aren’t the most scintillating topic at dinner parties, but for the engineering community, they are a critical element of properly designing water storage tanks.
An area that is being much discussed right now is AWWA D102, the most complete standard covering the greatest number of individual systems and the most innovative coating technologies. AWWA’s Standards Council is currently reviewing proposed changes to D102, which will add two new coating systems that offer high performance with low environmental impact.
The standard covers surface preparation, six generic classifications of Outside Coating Systems (OCS) and five generic classifications of Inside Coating Systems (ICS). Design professionals also value D102 because it covers the issues of ventilation, tank disinfection and the first-year anniversary inspection.
For a good overview of the D102 topic – present and future – read a recent article in CE News entitled Potable Water Priorities, in which my colleague Tony Ippoliti, an AWWA D102 committee member, provides guidance for engineers on which standards are pertinent to tank construction and painting, and details the importance of D102 generally in facilitating the selection of coating technologies.
July 1, 2010
All surfaces receiving an application of thin film, medium film, laminate or mortar systems must be structurally sound, clean and dry. Proper surface preparation is an extremely important factor in the immediate and long-term successful performance of applied coating and lining systems.
The contractor responsible for the installation of a coating or lining system shall be provided a substrate that is clean, durable, flat, pitched to specifications, dry and free of surface contaminants. Providing the “proper substrate” is the responsibility of the owner, the owner’s appointed representative and the concrete contractor, unless specifically stated otherwise,
Proper Surface Preparation
Proper surface preparation includes the following:
1. Inspection of the concrete substrate
2. Removal and replacement of non-durable concrete
3. Decontamination of the concrete surface
4. Creation of surface profile
5. Repair of surface irregularities
- Inspection of the concrete substrate is critical to determine its general condition, soundness, the presence of contaminants, presence of moisture vapor emissions and the best methods to use in preparation of the surface to meet the requirements of the owner or the owner’s appointed representative. A proper evaluation will lead to the selection of the proper tools and equipment to accomplish the objective.
- Removal and replacement of non-durable concrete must be accomplished prior to installation of the coating or lining system.
- Decontamination of the concrete surface requires the removal of oils, grease, wax, fatty acids and other contaminants, and may be accomplished by the use of detergent scrubbing with a cleaner and degreaser, low pressure water cleaning (less than 5,000 psi), steam cleaning, or chemical cleaning. Rinse thoroughly to achieve a final surface pH between 8.0 and 11.0. Refer to ASTM D4262.
- Creation of surface profile can be accomplished by a number of methods, each utilizing a selection of tools, equipment and materials to accomplish the intended purpose
- Repair of surface irregularities including spalls, cracks, deteriorated joints, slopes, areas near transition zones, such as around drains and doorways, etc. must be repaired prior to the placement of the polymer system.
Surfaces to receive the coating or system must be inspected after the surface is prepared to insure that the substrate is sound and structurally durable. Areas found to be unsound or non-durable must be removed and replaced.
Subsequant blog will highlight various methods of surface preparation for concrete surfaces.