Physical Properties of Single-Component Steel Structure Paint

• Easy and convenient to apply (single-component system)
• Fast drying with good adhesion
• Good anti-rust performance and color durability in normal corrosive environments
• Gloss level: varies depending on the manufacturer
• Color: Alkyd anti-rust primers are typically gray or reddish-brown, while alkyd topcoats are available in a wider range of colors
• Coverage: Depends on several factors such as surface condition, applicator skill, surface preparation, and intended use.

Main Components of Alkyd Anti-Rust Paint

• Long-oil alkyd resin
• Anti-corrosive pigments
• Fillers (extenders)
• Other special additives
• Solvents

Application of Single-Component Alkyd-Based Steel Structure Paint

• Before painting, the surface must be clean, dry, and free from impurities.
• For surfaces with existing old paint layers, paint remover should be used to completely eliminate the old coating.
• Application should be carried out when the surface temperature is at least 3°C above the dew point. Temperature and humidity must be measured directly at the surface to be coated.
• Alkyd-based steel structure paint is a single-component system, so it only needs to be stirred thoroughly before application. It can be applied directly onto the prepared surface using a roller, brush, or spray equipment.

Coating system: 1 coat of anti-rust primer + 2 coats of topcoat. Depending on specific requirements, 2 coats of primer + 3 coats of topcoat may be applied. The minimum interval between coats is 2 hours, and the maximum is 8 hours under environmental conditions of approximately 30°C.

Two-Component Epoxy Steel Structure Paint

Epoxy steel structure paint is a two-component coating system that forms a protective film resistant to corrosion and abrasion, while extending the service life of steel structures in harsh environments such as ships, fishing vessels, coastal structures, chemical storage tanks, oil tanks, and crude oil storage facilities.

Steel structures in highly corrosive environments (such as coastal areas) are commonly protected with epoxy coatings.

Physical Properties of Two-Component Epoxy Steel Structure Paint

• Epoxy paint consists of two components: Component A (base/paint) and Component B (hardener/curing agent)
• Epoxy steel structure paint offers excellent abrasion resistance and outstanding resistance to seawater, crude oil, fuels, and mechanical wear.
• It can be applied to both new and existing steel structures.
• For application, simply remove all impurities from the surface before directly applying the epoxy coating.
• Color: Similar to single-component alkyd anti-rust primers, epoxy anti-rust primers are typically available in gray and red oxide. However, epoxy topcoats are available in a wider range of colors.
• Theoretical coverage: Coverage depends on the type of paint, applicator skill, and surface condition, as well as the dry film thickness. For example, with a dry film thickness of 100 microns, 1 kg of epoxy steel structure paint can cover approximately 7–8 m².

Epoxy paint is particularly suitable for steel structures exposed to water environments.

Main Components for Producing Two-Component Epoxy Steel Structure Paint

• Epoxy resin (75%)
• Amide hardener
• Anti-corrosion additives (e.g., zinc oxide, zinc phosphate)
• Fillers (extenders)
• Solvents

How to Use Epoxy Steel Structure Paint

• First, the surface to be painted must be cleaned thoroughly: remove all dirt, oil, old paint layers, and other contaminants from the surface.
• If there are surface defects such as dents or cracks, use specialized filler for steel structures to make repairs before coating.
• The surface temperature and surrounding environment should be similar to the conditions used when applying single-component alkyd steel structure paint.

Application tools can include brushes, rollers, or spray equipment.

Mixing and Application Instructions

Because epoxy steel structure paint is a two-component system, it must be mixed before use. The mixing process of the paint:

• Stir Component A and Component B separately first. Then slowly pour Component A into Component B and mix thoroughly until a uniform mixture is obtained. Use a mechanical mixer or electric paint stirrer.
• Do not pour Components A and B together and then mix immediately, as this may result in improper blending and reduce the quality of the final coating film.
• Thinner may be used to adjust viscosity (depending on the technical requirements of each paint manufacturer), but it should not exceed 5–10% of the paint volume. Note that thinner should be added only after Components A and B have been mixed together.
• Unlike alkyd steel structure paint, epoxy steel structure paint has a limited pot life (depending on the manufacturer). Typically, it ranges from 6 to 12 hours. Therefore, application must be completed within the specified pot life; once this time has expired, the paint will cure (harden) and can no longer be used.
• After mixing, apply the epoxy steel structure paint directly onto the prepared surface using a roller, brush, or spray equipment.

Recommended coating system: 1 coat of epoxy anti-rust primer + 2 coats of epoxy topcoat. Depending on specific requirements and intended use, 2 coats of epoxy primer + 3 coats of epoxy topcoat may be applied.

The interval between coats depends on ambient temperature, paint type, and surface conditions. Typically, the minimum recoat time is 6 hours and the maximum is 12 hours.

Polyurethane (PU) Steel Structure Paint

Polyurethane steel structure paint is used to provide long-lasting protection for machinery, outdoor steel structures, industrial storage tanks, underground piping systems, ventilation ducts, bridges, ships, and more.

Physical Properties of PU-Based Steel Structure Paint

• Fast drying and high hardness
• Excellent abrasion resistance
• Withstands severely corrosive environments
• Excellent resistance to UV, solvents, and chemicals
• Excellent adhesion on properly prepared epoxy or alkyd anti-rust primer surfaces
• Extends service life and long-term durability of steel structures
• Wide range of colors similar to alkyd and epoxy steel structure topcoats
• Packaging specifications and coverage rate of polyurethane steel structure paint are similar to those of two-component epoxy steel structure paint.

PU paint is commonly used for coating machinery and equipment.

Main Components of 2K PU (Polyurethane) Paint

• Acrylic resin
• Hardener: HDI (e.g., Coronate HX, Coronate HX-T)
• Fillers (extenders)
• Industrial solvents

Application of PU-Based Steel Structure Paint

The application procedures and precautions are similar to those for epoxy steel structure paint. Recommended coating system: 1 coat of epoxy anti-corrosion primer + 2 coats of PU (polyurethane) steel structure topcoat