| |
For maintenance and repair of steel constructions in industrial operations (e.g. chemical or steel factories), the old coatings are normally not being fully removed, and neither the rust is removed (by e.g. sand blasting).
Cost considerations also often do not allow to use CORREPAIR® 1 (“removes the rust”).
In co-operation with a big chemical company near by Hamburg, a wide testing program was started to evaluate the suitability of CORRPASSIV® in direct application on rust and on old coatings. It is the goal to find a “surface tolerant” [1] primers and top coats suitable for this application. The goal would be to stop further rust formation.
An extensive comparison program including most of the commercially available and well recommended “surface tolerant” coatings systems is ongoing, testing pre-rusted panels in the laboratory and rusted test areas in open air at the chemical factory site.
The test is not yet completed. An intermediate evaluation after 728 h of VDA climate cycling test shows, that CORRPASSIV® 4904 is the best “surface tolerant” system tested up to now.
|
Picture 0262728 shows one of the best previously available coating systems for such an application, being provided by one of the leading suppliers in the market. Along the scratches, undermining and blistering are strongly visible. |
Picture 0285728 shows CORRPASSIV® 4904 also applied on pre-rusted plates. No undermining, no blistering is being detected. The structures on the surface in the left picture area is due to the surface structures of the rust. |
CORRPASSIV® is best suitable for the maintenance and repair of rusted steel constructions directly to be applied on rust, which is only mechanically pre-treated. It shows nice adhesion on rust and on most of the old coatings.
[1] hence a system, which can be applied directly on rust, which is only mechanically treated to remove most of the loose rust, and which is capable of adhesion on rust and stops further rust formation
