Summary for hot dip galvanizing alternative Discussion
Hot dip galvanizing for household gas tanks is the focus of this thread, with Ron Atkin asking how a proposed two-coat system compares and whether there are better replacements. His factory suggested a zinc-rich primer with over 90% zinc at more than 40 microns, followed by a resin top coat of more than 40 microns, for a total coating thickness above 80 microns. The excerpt provided does not include any replies, so no alternative was endorsed or rejected in the visible discussion. Based on the question alone, the key issue is whether a painted zinc-rich system can truly match the corrosion protection and durability of hot dip galvanizing for gas tanks, and what substitute process would be most suitable if galvanizing is unavailable due to environmental restrictions.
Q. Hi folk.
We are making household gas tanks which were to be hot dip galvanized, but China is no longer permitting galvanizing activities (pollution issue).
Our factory wants to supply the goods coated as follows as an alternative.
“First layer >40 micron thick zinc rich primer containing over 90% zinc. Second layer resin top coat >40 microns. Total surface coating >80 micron”.
How far short of galvanizing is would this surface be?
What better/new alternatives could we use to best replace hot dip galvanizing?
Ron Atkin
Company Managing Director – New Zealand
November 27, 2017