Anti-Corrosion Primer
Dachin DZ-6000
Cold spray zinc
Overview
Cold galvanizing, also known as cold zinc spray or zinc-rich coating, is a material protection technology that applies zinc coating onto substrates through painting. It achieves equivalent anti-corrosion effects to hot-dip galvanizing, thermal spraying (zinc/aluminum), featuring dual protection mechanisms: cathodic protection and barrier protection. Widely used for steel structures in bridges, marine engineering, petrochemical, and paper industries.
Main Components
Cold galvanizing coating is a single-component anti-corrosion product containing atomized ultra-fine zinc powder (95%+ purity, 3-6μm particle size), resin, and volatile solvents. This formulation delivers exceptional corrosion resistance for steel substrates.
Key Features
- Dual protection mechanism (cathodic + barrier) outperforms thermal spray zinc and conventional zinc-rich coatings. Ideal replacement for hot-dip galvanizing and thermal spraying. Exhibits excellent adhesion, flexibility, and impact resistance.
- Functions as standalone coating or primer in multi-layer systems.
- High zinc content in dry film (95%+). Free from isocyanates, toluene, methylene chloride, and MEK.
- Operating temperature range: -40℃ to +120℃.
- Enhances rebar corrosion resistance without compromising concrete bonding strength.
- Single-component system allows versatile application (brush, roller, air/airless spray, dip, electrostatic). Suitable for shop or field application. Excellent recoatability for hot-dip galvanized maintenance.
- Unique coating fusion: New layers integrate seamlessly with existing cold galvanized surfaces.
- Ambient curing enables rapid handling (short drying time).
Primary Applications
For corrosion protection of new/existing steel structures in marine, industrial, and urban environments: bridges, buildings, pipelines, sluice gates, rail transit, etc. Complies with JT/T 1266-2019 Technical Specifications for Cold Galvanizing of Bridge Steel Structures and HG/T 4845-2015 Cold Zinc-rich Coatings.
Technical Specifications
| Film Color & Appearance | Zinc gray, uniform surface free from particles, pinholes, bubbles, or wrinkles |
|---|---|
| Gloss | Matte |
| Specific Gravity, KG/L | 2.7±0.1 |
| Typical DFT | 80-100μm |
Packaging
| Net Weight / Kg | Volume / L |
|---|---|
| 30 | 11.1 |
Basic Parameters
| Mixing Ratio | Single-component |
|---|---|
| Pot Life | Resealable container allows reuse of remaining material |
| Theoretical Coverage | Approx. 6.25㎡/L at 80μm DFT |
Recoat Intervals
| Temperature | Touch Dry | Min Interval | Max Interval |
|---|---|---|---|
| 10℃ | 25 min | 24 h | Unlimited |
| 25℃ | 15 min | 16 h | |
| 30℃ | 10 min | 12 h |
*Data based on 80μm DFT on tinplate substrates.
Application Conditions
Agitate Dachin DZ-6000 mechanically before use. Dilution ratio (by weight): Cold galvanizing : Thinner = 1 : 0-10%.
Applicable methods: brush, roller, conventional/airless spray. Ambient temperature: 0-50℃. Steel surface ≥3℃ above dew point.
Brush/Roller: Use soft-bristle brushes for heavy coating absorption. Maintain uniform thickness (50μm/coat ×2 coats=100μm). Avoid over-spreading.
Note: The microporous zinc surface gradually densifies via zinc carbonate formation (CO₂ + moisture reaction). Immediate topcoating is recommended before pore closure (typically within 1-2 months).
Avoid direct application of Dachin H53-90 Sealer over 50μm DFT to prevent bubbles/pinholes (aggravated by high temperatures). Excess thickness (>200μm) may cause solvent penetration and delamination.
Recommended procedure: 1) Apply 25-30μm mist coat of sealer after zinc curing. 2) Allow 4h drying. 3) Apply full sealer thickness. This isolates solvent penetration while allowing air escape.
Coating System
Intermediate: Dachin H53-90 Cold Galvanizing Sealer (epoxy mica iron composite)
Topcoats: Dachin AL 711 Metallic Coating, Dachin FC 880 Fluorocarbon, Dachin PU 770 Polyurethane, Dachin PS 990 Polysiloxane
Warning: Alkyd coatings incompatible. Conduct compatibility tests before application.
Surface Preparation
Critical requirement: Clean steel or galvanized surface.
Steel: Blast-clean to Sa2.5 (ISO 8501-1). Weld seams: Power-tool clean to St3.
Galvanized substrates: Remove contaminants (dust, oil, salt, white rust) to St2.
Must apply directly to bare steel/galvanized surfaces. Remove existing coatings completely.
Mixing
Single-component system. Add Dachin Thinner X15 if required. Mechanical agitation mandatory.
Application Methods
| Conventional Spray | 100-mesh filter | Nozzle: 1.5-2.0mm | Pressure: 0.3MPa | DFT: 50μm/coat ×2 |
|---|---|
| Airless Spray | 50-60 mesh filter | Equipment: Chongqing Changjiang QPT9C/QPT3256 | Compression: 32:1 | Pressure: 10-16MPa | Flow: ≤5600ml/min | Nozzle: 1.5-2.5mm | DFT: 50μm/coat ×2 |
| Thinner | Dachin Thinner X15 |