Why preparation is essential
Proper material preparation is critical to achieving a durable, uniform zinc coating during the hot-dip galvanizing process. Poor preparation can lead to defects such as uncoated areas, surface contamination, or coating delamination. For this reason, both companies and workshops must follow best practices before sending parts for galvanizing.
Good preparation ensures maximum zinc adhesion, process efficiency, and compliance with ISO 1461 quality standards.
What materials are suitable?
- Carbon steel and iron are ideal for hot-dip galvanizing.
- The surface must be free of any paint grease oils or weld slag.
- Avoid coated plated or previously treated parts unless fully stripped.
If in doubt, submit technical specifications or samples to your galvanizer in advance.
Practical guidelines for material preparation
1. Clean surfaces
All components should be delivered free of paints, stickers, oils, silicones, or surface treatments. Surface contaminants can prevent zinc adhesion.
2. Use compatible welding materials
Avoid stainless steel or copper-based alloys in welds. Discontinuous or porous welds may trap air and affect coating quality.
3. Design with drainage and venting holes
Hollow or tubular structures must include drainage and vent holes to allow molten zinc to flow and escape safely.
4. Round sharp edges and corners
Smoothed edges reduce stress concentration and allow for a more even zinc coating.
5. Avoid narrow gaps or double-sheet joints
Gaps may trap liquids or flux and prevent proper galvanizing.
Documentation to provide
To ensure efficient processing, companies should include:
- Technical drawings or 3D files
- Material specifications
- Indication of critical surfaces or areas requiring masking
- Instructions for stacking or handling if applicable
This information allows the galvanizing provider to plan the treatment effectively and avoid costly delays or defects.
Zincol Lombarda: technical support before, during and after
At Zincol Lombarda, we assist manufacturers, workshops, and construction firms throughout Milan, Lecco, Bergamo, and Como in properly preparing materials for hot-dip galvanizing.
Our team provides pre-treatment consulting, visual inspection, and feasibility analysis to ensure full compliance with UNI EN ISO 1461 and best practices. With decades of experience and a deep knowledge of material behavior, Zincol Lombarda offers reliable, Made in Italy solutions for a flawless finish.
