Advanced Zinc Coating Systems for Long-Lasting Corrosion Protection
Alland Steel provides a comprehensive range of galvanized steel pipes — including Hot-Dipped Galvanized (HDG) and Zinc-Aluminum-Magnesium (ZAM) coatings — engineered to deliver superior corrosion resistance, weather durability, and extended service life. Designed for construction, solar, agricultural, and industrial applications worldwide, our galvanized pipe series ensures long-term reliability even in harsh environments.
The Galvanized Steel Pipe Series covers both HDG and ZAM coating technologies, offering a balance between proven zinc protection and advanced alloy innovation.
HDG pipes feature a traditional molten-zinc coating for excellent abrasion and sacrificial protection.
ZAM pipes introduce aluminum and magnesium alloys for superior corrosion resistance and self-healing properties.
Both types are manufactured under international standards (ASTM, EN, JIS) with customizable dimensions and surface finishes.
Galvanized Steel Pipe Series — HDG & ZAM Coatings
The Alland Steel galvanized series includes two advanced coating technologies that provide durable corrosion protection for infrastructure, construction, and industrial systems. Both use a metallic zinc-based layer but differ in alloy composition and performance.
1. Hot-Dip Galvanized Steel Pipe (HDG)
HDG pipes are produced by immersing fabricated steel (ERW or seamless) in molten zinc at approximately 450°C, forming a metallurgically bonded zinc–iron alloy coating. This tough and uniform layer offers exceptional barrier and sacrificial protection — ideal for outdoor, structural, and water-conveying applications.
2. Zinc-Aluminum-Magnesium Coated Steel Pipe (ZAM)
ZAM steel pipes feature a new generation of metallic coating composed of zinc, aluminum (1.5–8%), and magnesium (1–4%), providing up to 3–5× higher corrosion resistance than traditional galvanizing. This ultra-dense alloy coating exhibits a self-healing effect at cut edges and is particularly suitable for solar frames, agricultural, and marine applications.
Common Specifications
Coating Options: HDG · ZAM — selected based on environment, corrosion exposure, and service life requirements.
Description
The Alland Steel galvanized pipe range includes two advanced coating systems — Hot-Dip Galvanized (HDG) and Zinc-Aluminum-Magnesium (ZAM). Both are designed for long-term corrosion protection, mechanical strength, and visual durability in demanding outdoor and industrial environments.
Hot-Dip Galvanized (HDG) Steel Pipe
HDG steel pipe is manufactured by immersing fabricated steel tubes in a molten zinc bath at approximately 450 °C. This process forms a dense, metallurgically bonded zinc-iron alloy layer that coats both the interior and exterior surfaces. The coating provides barrier and sacrificial protection, ensuring superior resistance to abrasion, weathering, and mechanical damage.
- Typical zinc coating thickness > 300 g/m² (≈ 45 µm) for strong, long-term protection.
- Excellent performance in outdoor, structural, and municipal applications.
- Complies with ASTM A123, ISO 1461, EN 10346, and JIS G3444.
| Product Name | Hot-Dip Galvanized Steel Pipe (HDG) |
|---|---|
| Manufacturing Process | Hot-dip galvanizing of ERW / Seamless pipes |
| Size Range (OD) | Φ21.3 – 914.4 mm (½″ – 36″) |
| Wall Thickness | 1.5 – 10 mm |
| Length | 6 – 12 m (customized) |
| Steel Grades | Q235, Q345, Gr.A / B, S235, S355 |
| Surface Finish | Bright crystalline zinc pattern (spangle) or smooth coating |
Zinc-Aluminum-Magnesium (ZAM) Steel Pipe
ZAM steel pipe is produced using a continuous hot-dip process that applies a Zn-Al-Mg alloy coating containing approximately 1.5 – 8 % Al and 1 – 4 % Mg. This dense, uniform coating offers 3 – 5× higher corrosion resistance than traditional galvanized coatings and provides remarkable self-healing ability at cut edges, effectively preventing red-rust formation.
- Exceptional corrosion resistance with long-term surface brightness and smoothness.
- Ideal for solar structures, coastal installations, and agricultural frameworks.
- Complies with EN 10346, JIS G3323, and ASTM A1046.
| Product Name | Zinc-Aluminum-Magnesium Coated Steel Pipe (ZAM) |
|---|---|
| Manufacturing Process | ERW process using Zn-Al-Mg coated steel coils |
| Size Range (OD) | Φ20 – 200 mm |
| Wall Thickness | 1.0 – 6.0 mm |
| Coating Weight | ZM80 – ZM400 (80 – 400 g/m²) |
| Steel Grades | S235, S355, DX51D+ZM, SGCC |
| Surface Finish | Bright fine-spangle metallic appearance |
Common Specifications
| Outside Diameter | Φ21.3 – 914 mm (½″ – 36″) |
|---|---|
| Length | 6 – 12 m (customized) |
| Shapes Available | Round · Square · Rectangular |
| Base Pipe Type | ERW / Seamless Steel Pipe |
| Coating Options | HDG · ZAM — selected based on environment, corrosion exposure, and service life requirements |
Specifications Sheet · Hot-Dip Galvanized Steel Pipe
Main Applications
Zinc-Aluminum-Magnesium (ZAM) and Hot-Dip Galvanized (HDG) steel pipes are selected for outdoor and high-humidity environments where long-term corrosion protection and mechanical reliability are critical. The metallic coatings provide stable performance in construction, utilities and industrial projects.
Infrastructure & Construction
Guardrails, bridges, handrails, scaffolding, industrial frames exposed to open-air conditions.
Agriculture & Greenhouse
Irrigation lines, fencing, greenhouse frameworks requiring low maintenance and rust prevention.
Power & Solar
Outdoor solar mounting structures and energy facilities benefiting from ZAM’s self-healing edge protection.
Water & Gas Distribution
Low-/medium-pressure pipelines for utilities and municipal systems.
Marine & Coastal
Coastal zones and harbors where coatings must resist salt spray and humidity.
Advantages
ZAM and HDG coatings both extend service life under harsh exposure; ZAM forms a regenerating protective film at scratches or cut edges, while HDG builds a dense zinc–iron alloy layer that delivers robust sacrificial protection.
- Corrosion Performance: Long-term durability in outdoor, humid and marine conditions.
- Self-Healing (ZAM): Zn-Al-Mg alloy film mitigates red rust at cut edges and minor scratches.
- Tough Bonding (HDG): Metallurgical zinc–iron layers provide abrasion resistance and strong adhesion.
- Lower Lifecycle Cost: Reduced repainting and maintenance versus painted alternatives.
- Compliance: Produced to EN/ASTM/JIS/ISO galvanizing and ZAM coating standards.
Packing & Transportation
Export packing preserves coating integrity throughout handling and shipment. Each bundle is identified for traceability.
- Bundle Packing: Steel straps / wooden frames with protective pads to prevent surface friction.
- Container Shipment: Recommended for ≤6 m lengths and small-to-medium volumes.
- Bulk Vessel: For large diameters / long lengths using wooden saddles and multi-layer wrapping.
- End Protection & Labels: End caps, spacers, and bundle tags with specs and batch codes.