ll surfaces must be primed with compatible primer and be clean, dry and free of oil, grease, loose mill scale, dirt, dust or other materials which would impair adhesion of the product to the substrate. In most cases, a water jet machine is used to remove dust or other dirt.
The primer must be applied in accordance with the primer manufacturer’s written instructions. Some of the primers which are used on the surface of steel structure are as follows:
-Epoxy Phenolic Primer
-Zinc Free Epoxy Primer
-Zinc Phosphate Epoxy Primer
Also, a keycoat layer should be used in order to increase the adhesion between fireproof coatings and primers (other than those approved by manufacturer). Keycoat Layer
This layer consists of the following materials:
-Water Application Method
The mixture should be applied to the surface in one layer with a thickness of about 1mm.
The drying time of this layer depends on temperature and atmospheric conditions (10-24 hours)
Mechanical piston, hydraulic piston or rotor stator type screw feed pump can be used. Paddle or ribbon-type mortar mixer with safety cover is also required.