The South African Institute of Marine Engineers and Architects (SAIMENA) is working with the International Zinc Association (IZA) to promote thermal zinc spraying for the local ship repair industry. âWe have excellent local expertise to help SAIMENA achieve its mandate to develop a dynamic and qualified marine engineering sector,â comments Simon Norton of the Africa office of IZA.
SAIMENA is the professional body that drives the growth and skill enhancement of the South African marine engineering sector, and works hard to bring new and advanced expertise to the fingertips of the marine engineering profession.
âWe continue to advance and promote marine engineering know-how and continuous development for marine engineers, ship repair engineers and designers. Working with professional bodies such as IZA enhances our capabilities, âcomments Rear Admiral (JG) Kevin Watson (retired), President of SAIMENA.
Zinc thermal spray can be applied to a variety of steel vessels, from trawlers to warships, fast patrol boats and fisheries patrol boats. This includes the superstructures, fittings and on-board metal framing which after thermal spraying of the zinc can be coated by the application of a zinc rich primer and epoxy coat to give a superb duplex coating system. sustainable.
The advantage of thermal zinc spraying is that it is possible to apply zinc coatings of varying thickness but typically up to about 100 microns. Spraying makes it possible to control and vary the thickness of the coating, even on different areas of the same structure and / or parts.
Thermal spraying allows zinc coatings to be applied to structures and components that are too large for hot dip galvanizing or that need to be galvanized in situ. The metallic coating is installed in a single application. Zinc coatings also have excellent adhesion to steel and abrasion resistance, allowing the structure to withstand rough use. However, above all they constitute a barrier to the environment and provide galvanic protection to the steel.
All grades of steel, including high alloy steels, can be thermal spray coated. Spraying does not affect the metallurgical structure of the steel. Since zinc adheres and coats instantly, no drying time is required. Designated topcoat operations can begin immediately, while paint systems of comparable grades may take several days to cure.
In terms of life cycle costs, Norton explains that the initial coating application costs are minimal compared to the maintenance costs over the life of the structure. Continuous maintenance is not necessary with a properly applied zinc spray coating. A single application provides excellent corrosion protection, including areas where minor mechanical damage may have exposed the steel. The additional application of organic epoxy topcoats provides an exceptional corrosion protection system.
IZA’s collaboration with SAIMENA is part of a long-term strategy to promote the development of South African engineers, the growth of the local maritime industry, as well as the increased use of zinc in the industry. industry, where its main application is corrosion protection of steel. Since the closure of the country’s only zinc refinery in 2011, it has relied heavily on expensive imports, a situation that IZA’s Africa office hopes to reverse by campaigning for the establishment of a new local zinc refinery.
“This is particularly important given the ambitious plan for the government-promoted infrastructure delivery program, which will require large tonnages of zinc-plated steel,” Norton notes.
âOur association with SAIMENA is an example of how we reach out to various professional organizations and associations to promote the benefits of specialized processes such as thermal zinc spraying,â Norton concludes.