With over 13 years of dedicated manufacturing in the steel fence sector, Pauleen has perfected a complete anti-corrosion system that goes far beyond ordinary galvanizing or simple spray painting. Our approach is rooted in metallurgical precision, rigorous surface preparation, and multi-layer coating technologies-ensuring that every fence leaving our factory withstands salt spray, UV radiation, and humidity for decades.
The Root Cause: Why Most Steel Fences Fail
Conventional steel fences often rely on a single layer of post-galvanization or a thin powder coat applied over minimally prepared surfaces. This leads to:
Underfilm corrosion due to inadequate phosphate conversion coating.
Cathodic delamination at cut edges and drill holes.
Filiform corrosion under the coating in humid environments.
Weld seam oxidation where the zinc layer is burned off during fabrication.
Pauleen's 13-Year Anti-Corrosion System – Layer by Layer
We don't just mask the problem; we eliminate it from the substrate up.
1. Base Material Selection – High-Strength Low-Alloy (HSLA) Steel
We start with HSLA steel with controlled carbon content (≤0.12%) and low phosphorus/sulfur levels, reducing the risk of intergranular corrosion. The steel is pre-shipment inspected using an optical emission spectrometer (OES) to ensure consistent chemistry.
2. Advanced Surface Preparation – The Foundation of Adhesion
Every profile undergoes a 7-stage pretreatment process:
Alkaline degreasing (removal of all mill oils and contaminants)
Rinsing with deionized water
Zinc phosphate nanoceramic conversion coating – creating a microcrystalline layer (2–3 g/m²) that enhances coating adhesion and delays underfilm corrosion
Rinsing with reverse osmosis water (conductivity <20 µS/cm)
Non-chrome sealing passivation – environmentally friendly yet highly corrosion-resistant
Hot air drying at 120°C before coating
3. Hot-Dip Galvanizing (HDG) – Internal Corrosion Barrier
Instead of thin electro-galvanizing, we employ hot-dip galvanizing per ASTM A123 / ISO 1461:
Minimum zinc coating thickness: 85 µm (for 3–6 mm steel sections)
Coating weight: ≥ 610 g/m²
The metallurgical bond creates Fe-Zn alloy layers (delta, zeta, and eta phases), providing cathodic protection even if the surface is scratched.
4. Zinc-Rich Epoxy Primer – Active Edge Protection
After HDG, we apply a zinc-rich epoxy primer (88% zinc dust by weight in the dry film) over all surfaces, especially critical at weld seams and punched holes. This primer provides sacrificial anodic protection and bridges any micro-porosity in the galvanized layer.
5. Polyester or PVDF Topcoat – Weather Shield
The final layer is a durable powder coating:
Option A (standard): Weather-resistant polyester powder – 80–100 µm thickness, >600 h salt spray resistance (ASTM B117) with <1 mm creep from scribe.
Option B (coastal/industrial): PVDF (polyvinylidene fluoride) coating – 70/30 Kynar 500®-based, providing >2,000 h of QUV-A accelerated weathering with ≤1 ΔE color change.
The coating is applied in a computerized electrostatic spray booth, followed by curing in a gradient oven (peak metal temperature 200°C for 10 minutes), achieving cross-linking density that blocks moisture and chloride ions.
6. Seam & Joint Sealing – The Overlooked Failure Point
All welded joints are re-treated with a cold-galvanizing compound (95% zinc) after welding, then over-coated with epoxy-polyester hybrid powder. We also use rubber gaskets at assembly points to prevent galvanic corrosion between different metals.
Validated Performance – Not Just Promises
Pauleen's steel fence system has been independently tested:
Salt spray resistance (ASTM B117): Exceeds 1,500 hours without red rust.
Cyclic corrosion test (ASTM G85 – Annex A5): 50 cycles – no blistering, no scribe creep >1.5 mm.
Impact resistance: Direct impact 20 in-lb (ASTM D2794) without cracking.
Humidity resistance (ASTM D2247): 1,000 hours – no delamination.
The Pauleen 13-Year Field Track Record
Our oldest zinc steel fence installations, dating back to 2011, are still in service in coastal Zhejiang and inland industrial zones. We regularly conduct post-installation inspections using electromagnetic coating thickness gauges and cross-cut adhesion tests (ASTM D3359 – rating 5A). The results consistently show less than 0.1% surface rust over 13 years.
Why Trust Pauleen as Your Supplier?
Integrated manufacturing: From steel roll forming to coating and assembly – all under one roof. No subcontracting means full traceability.
ISO 9001:2015 & ISO 12944 certified (corrosion protection of steel structures).
Customizable: We adjust coating thickness, color (RAL or custom), and fence design (ornamental, welded mesh, or picket) to your project's corrosivity category (C3 to C5-M according to ISO 9223).
Bulk & OEM welcome – We ship globally with anti-rust packaging (edge protectors, VCI film, and plywood crates).
Stop Planning for Replacement. Start Building for Generations.
Don't let hidden corrosion eat into your reputation or budget. With Pauleen's 13-year specialized know-how, your next steel fence won't just look good at delivery-it will remain structurally and aesthetically sound long after cheaper alternatives have turned to rust.
Contact our engineering team for a corrosion protection proposal tailored to your local environment. Visit our product page or request a sample kit to see the Pauleen difference.