â‘ Performance and technical indicators of the selected primer
The primer is very important for the anti-corrosion performance of construction machinery products. With the rapid development of the construction machinery industry and the intensification of market competition, the requirements for primers in construction machinery are good anti-rust performance, strong adhesion, and high mechanical strength. Salt water resistance; easy to brush, easy to polish, no sag, can adapt to a variety of coating methods; has a good matching with various commonly used putty, intermediate coat and top coat, convenient construction; less pollution, reasonable price.
See Table 3-3-126 for the specific performance requirements of the antirust primer.
â‘¡Introduction to commonly used primers
a. Epoxy zinc-rich shop primer
Using epoxy resin as the base material, adding ultra-fine zinc powder, anti-rust filler, solvent, additives, using polyamide resin as curing agent. It has cathodic protection, excellent anti-rust performance, good adhesion, heat resistance, welding, cutting, etc. The burning area is small, does not affect the welding performance, and has the characteristics of oil resistance and water resistance. It is mainly used as a temporary protective primer for plates or steel structures after shot blasting or sandblasting.
b. Iron red epoxy primer
It is prepared by grinding quick-drying epoxy resin, iron red, anti-rust pigments, additives, and mixed solvents. It has the characteristics of fast drying rate, excellent physical and mechanical properties of the coating film, strong water resistance and anti-rust ability, and good adhesion .
c. Epoxy zinc-rich primer consists of epoxy resin, ultra-fine zinc powder, solvent, additives, and polyamide resin as curing agent. It has cathodic protection, excellent antirust performance, good adhesion, water resistance and oil resistance. Suitable for shot blasted or sandblasted steel surfaces.
d. Polyurethane primer
It is composed of modified acrylic resin polymer, non-yellowing isocyanate curing agent, anti-rust pigment and filler. It has excellent water resistance and seawater resistance, excellent wear resistance, good oil resistance and anti-rust performance, tough paint film and strong adhesion.
e. Epoxy ester primer
It is composed of modified quick-drying epoxy ester resin, anti-rust pigments and fillers. It has the characteristics of tough paint film, good adhesion, excellent chemical resistance, abrasion resistance, water resistance, sea water resistance, and excellent filling properties.
f. Alkyd primer
It is composed of alkyd resin, special resin and anti-rust pigment. Strong adhesion, good antirust performance, good seawater resistance and oil resistance, good construction performance, and low price, but poor compatibility with intermediate coatings or topcoats with high quality requirements. Therefore, it is currently used in construction machinery The application of the industry is gradually decreasing.
