In our previous posts, we discussed the basics of galvanizing and the essential design considerations. Today, we’ll focus on the materials suitable for galvanizing and how modular design can enhance the galvanizing process and overall project efficiency. 

Suitable Materials 

Steels: 

Most ferrous materials, including mild and low alloy steels, can be galvanized. Iron and steel castings are also regularly and successfully galvanized. Even steel fabrications that incorporate certain stainless steel parts and fittings are able to be galvanized, though this is not a recommended practice. For detailed information, you can refer to AS/NZS 2312.2, which lists materials suitable for galvanizing and their respective Australian Standards. 

Special Considerations: 

Assemblies with soft-soldered parts or aluminium rivets cannot be galvanized. Brazed assemblies may be galvanized, but it’s best to consult with your galvanizer during the design stage. 

Castings: 

Galvanizing castings require careful design and preparation to ensure high-quality coatings. Key design tips include: 

– Uniform section thicknesses. 

– Large radii at junctions. 

– Avoiding deep recesses and sharp corners. 

– Abrasive blast cleaning to remove foundry sand and surface carbon. 

Modular Design 

Benefits: 

Modular design involves creating structures in modules for later assembly by bolting or welding. This approach offers several advantages, including: 

– Overcoming limits of galvanizing bath sizes 

– Simplified handling and transport. 

– Potential cost savings in manufacturing and assembly. 

– Easier maintenance and repair. 

Double End or Progressive Dipping: 

Large or unusually shaped items can be galvanized using double end dipping, where the item is partially immersed in the bath, then withdrawn and the orientation adjusted to immerse the remaining ungalvanized part. This process ensures complete coverage, though an overlap of the galvanized coating may occur, which should be considered for aesthetic finishes. 

Choosing the right materials and adopting modular design techniques can greatly enhance the effectiveness of the galvanizing process. These practices ensure high-quality coatings, simplify logistics, and can lead to cost savings. In our next post, we’ll discuss general fabrication guidelines and tips for designing items for durability.