Problem Solving Forum
April 22 - April 28, 2013
Is there a place for using “rust convertors” in heavy-duty maintenance projects?
Selected Answers
From
Car F. of Municipal City on
November 12, 2013:
I would never use a rust converter under a high pe ...read more
I would never use a rust converter under a high performance coating, mainly because exotic coatings requires a good, sound, clean and anchor-profiled surface. Using a rust converter defeats the above requirements.
From
Krzysztof Warcho? of PPG on
November 9, 2013:
It is not an accident that all "heavy duty" paint ...read more
It is not an accident that all "heavy duty" paint systems are based on "heavy" abrasive blast cleaning to bare steel or almost bare steel, Sa 3 or Sa 2,5 according to ISO 8501-1 2007. Any "rust convertors" can be good enough for C1 or C2, according to ISO 12944.
From
Javier Figarella of Ecotek Investments Inc. on
May 22, 2013:
Rust converters, particularly those made of tannic ...read more
Rust converters, particularly those made of tannic or galic acid, are suitable to prepare ferrous surfaces prior to application of protective coatings, when the thicknes of the rust layer is less than 14 mils. the rust converter must contain a resin that adheres strongly to the surface and prevents the presence of oxygen due to impermeability.
They reduce in many cases the use of costly abrasive methods of surface preparation.
From
Simon Hope of Bilfinger Salamis on
May 1, 2013:
Rust converters are one o ...read more
Rust converters are one of the theoretically wonderful materials that do not live up to the hype. Phosphoric acid- based materials tend to be water based and use what is effectively a domestic emulsion paint as the vehicle. This is fine for reacting the corrosion (iron oxide to iron phosphate) but effectively leaves a layer of emulsion paint on the surface. This is fine if you are putting on a weak, single-pack system, but it is debatable whether it is fit for purpose under a typical heavy duty system such as two-pack epoxies, as would be normally expected. There have been several failures where the mix of technologies is not fully understood. In reality, it is difficult to beat proper preparation with a correctly specified coating system applied, though 'snake oil' salesmen would love you to believe otherwise!
From
trevor neale of TF Warren Group on
April 30, 2013:
Rust converters embrace a ...read more
Rust converters embrace a broad range of products. Major drawback is they do not generate a profile or anchor pattern and therefore are not suitable for high performance protective coatings where the surface preparation is an integral part of the specification to ensure long-term durability.Where there is a job or coating manufacturer's specification requiring abrasive blasting to ensure durability, they are not an option.
From
Carl Thompson of Hill Brothers on
April 26, 2013:
Rust convertors, particul ...read more
Rust convertors, particularly those using phosphoric acid, are commonly used in these applications: 1.) Factories 2.) Refineries 3.) Industrial Plants 4.) Chemical Plants 5.) Ship Yards 6.) Fleet Operations 7.) Utilities 8.) Municipalities