Abstract
Water-borne coatings accounts for less than 3% of the total heavy duty (HD) protective coating market in Europe. There is however an increasing use of water-borne coatings in typical HD protective coating market segments such as infrastructure, oil & gas, power, tankage, marine and chemical industry. The average growth rate (AGR) for water-borne coating technology is surpassing the AGR for conventional solvent-borne coatings, mainly due to an increased focus on health and environmental issues and implementation of environmental legislation in EU and NAFTA. An increasing number of successful case histories are proving that you can use water-borne coatings to protect steel from corroding even under extreme conditions. The HSE aspects is just an extra bonus for using water-borne coatings the real benefits are high performance, cost savings by higher throughput due to shorter drying time/shorter recoating times, lower insurance premium, no expenses for thinners and shorter down time due to fewer coats or odor problems from solvents.
This presentation will put focus on three water-borne technologies that are suitable for HD corrosion protection i.e. acrylics, epoxies and inorganic zinc silicates. Both results from severe accelerated testing and real life field experiences will be used to illustrate the technologies suitability. In particular new developments in water-borne epoxy primer technology will be highlighted. This new technology will open up possibilities for use of water-borne coatings in HD areas were only solvent-borne coatings have been used so far, like for instance protecting offshore installations from corrosion.
Nobody should ignore the fact that there is a limitation for use of water-borne coatings in the HD area, with regard to climatic conditions on site. Fully understanding ”the rules of the game” with regards to temperature, relative humidity and ventilation requirements will enable the user to have as few limitations as possible and avoiding early failure of the coating system. The author will present and discuss new findings that will answer such questions such as when will a hydrophilic water-borne coating become water-resistant enough to support extreme weather conditions, how long time depending on climatic conditions does it take for all the water to evaporate from a water-borne coating, what are the limits for film thicknesses of water-borne coatings before there is a risk of entrapment of water in the coating film etc. There is a big need to educate the users of water-borne coatings in the HD corrosion protection area to reduce the skepticism and assure that the coating job is always done correctly the first time.
