Giving special attention to surface preparation and eliminating surface contaminants prior to coating can essentially eliminate premature coating failure.
The most damaging form of corrosion is localized corrosion, which can be prevented and controlled by using corrosion inhibitors, cathodic protection, and protective coatings.
On static structures, such as the steel legs of an offshore oil platform or the hull of an floating production, storage, and offloading (FPSO) vessel, the structural integrity of the welds need to be visually inspected and assessed. If the substrate is covered in biofouling that isn’t easily removed, a large amount of force is required to scrape it off, which may damage the underlying protective coating and leave the substrate vulnerable to corrosion.
The Canadian Standards Association developed CSA Z245.30-141 for external field-applied coatings on steel pipelines. It defines requirements for the qualification, application, inspection, and testing of external oil and gas pipeline coatings applied in the field or shop.
Corrosion poses a threat to all infrastructure, and the economic impact of corrosion represents an annual cost of billions of dollars. There are many advantages of planning for corrosion control and mitigation. It is important that owners and operators of high-value assets understand the cost implications of the effects of corrosion.
The purpose of this article is to draw some attention to the importance of surface preparation and coating inspection and perhaps change some attitudes and the all-too-common practice of assigning less than qualified and experienced personnel to inspect surface preparation and coatings.
NACE International recently published five new joint companion wet abrasive blast (WAB) standards with the SSPC: The Society for Protective Coatings. These standards define the processes for preparing a carbon steel surface to a specified degree of surface cleanliness using a WAB cleaning method.
Scientists have developed a non-chrome primer system by incorporating carbon nanotubes (CNTs) modified with organic corrosion inhibitors into an epoxy-based resin. The goal of the coating development effort was to identify promising CNT-containing non-chrome primer formulations that perform comparably to traditional chromated ones.
A novel, organic zinc-rich primer coating technology relies on a combination of zinc dust, hollow glass spheres, and a proprietary activator to provide cathodic protection with greatly improved mechanical properties (crack resistance) and adhesion.
A unique wrap was used to repair a seawater bulk media filter vessel on an offshore oil and gas platform in the Gulf of Mexico. The bottom of the vessel was suffering from external damage due to the heavily corrosive environment and seawater being transported.
A common coating scenario is that a contractor blasts all day long, then experiences delays before coating the blasted surface. A dehumidification system can help with meeting specifications for application and achieving customer satisfaction.
Some of the most critical uses of protective coatings involve service conditions that require the use of coatings as linings. They may be the same coatings that are used in atmospheric or underground service, but they are usually specially formulated for three specific purposes.
When a 200-ft (61-m) stretch of an arch tunnel on a stormwater collection line in the old town section of Guangzhou, China suffered severe damage to the brick-and-masonry structure due to root intrusion and corrosion, a spray-applied lining was used for rehabilitation.
A single-pack epoxy coating with epoxy-amine reactive functionality was recently developed that delivers reasonable shelf life and a high level of corrosion resistance that is comparable to two-component epoxy polyamide coatings.
Inorganic zinc silicate coatings, whether solvent- or water-borne, provide a number of unique challenges for the specifier and applicator. This article answers questions relating to selection, application, and maintenance of these coatings.