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Corrosion Policy Decision Making


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the type and amount of paints, hardener, and solvents of each layer is proper and under the manufacturers recommendations.

      Checking the color shade, density, and weight of the paint for each layer and reviewing its conformity according to the catalog and data sheets is also recommended. Other features to be careful about are appearance of the wet and the dry film (WFT and DFT) as well as possibility of complications for each layer preferred.

Photo depicts some typical complications of the paints resulting from poor quality paint features.

      2.2.5.5 Paint Warehousing and Storage

      One of the problems for paint application projects is the long‐time duration between the paint production and its use in the field. Most industrial users buy paint a few months before using it due to the long QC test time, and storage of paints in most projects can be up to a year. In some countries, due to political and economic reasons early forecasting and purchasing are also needed.

      In the executive projects, a separate warehouse is not provided for the paints and they may be stored with other equipment in a public warehouse. The standard conditions for paint storage, such as setting the right temperature, are not indicated most of the time; this is another problem that reduces the paint quality. The method of storing and using paints during storage is very important and stated in manufacturer catalog.

      2.2.5.6 Role of Executors and Contractors

      2.2.5.7 Surface Preparation

Photo depicts examples of unqualified workers. Photo depicts some weakness of the surface preparation. Paint application on rusted surface (left). Unsuitable abrasives and reuse of them several times (right). Weak surface preparation on weld lines (down).
Preparation methods Adhesion (MPa)ASTM D4541 Disbanding condition
Washing with white sprite 1.73 Paint layer from metal surface
Wire brush ST3 3.19 Paint layer from metal surface
Weak acid washing 2.89 Paint layer from metal surface
Hard acid washing 4.48 Paint layer from metal surface
Phosphating 4.30 Paint layer from metal surface
Wet sand blast, water blast 8 Paint layer from metal surface
Dry sand blast Sa3 11.63 Paint layer from metal surface

      In other research, the effect of different types of abrasives on steel preparation was investigated. Physical and chemical properties of tested abrasives are discussed in [17–19].

      Often, the functional performance of abrasives, such as the effect on primer adhesion is very important. It affects the mechanical stability of the film, as well as its chemical resistance, especially when the film is exposed to humid and saline environments during service time. The author investigated the effect of a number of abrasives on cured film performance by doing several tests. For that, some samples were blasted by different abrasives. They were coated with the same paint, having nearly dry film thickness. Then they were tested in a humidity chamber according to ASTM D2247, and in a salt spray chamber according to ASTM B117 [20, 21].

      In these experiments, silica sand compared with different