When it comes to products made of steel used in construction and manufacturing, one of the most commonly used items is galvanised stainless steel. This is because of their innate durability and resistance. Structural steel and fabrication specialists use galvanisation to imbue Pipes, nails, beams, plates, bars, rods, and other industrial products with strength and corrosion resistance.
Wire mesh, in particular, plays quite a critical role in thousands of commercial and industrial applications. So how exactly are galvanised wire mesh made? Read on and find out how the process of making it works.
Making Galvanised Wire Mesh
Galvanisation involves coating steel products with a robust outer layer of zinc, making them stronger and more resilient. The same thing is applied when making galvanised wire mesh. Application of the coating can be made in a couple of ways, such as:
The hot dipping method creates a physical and chemical bond between the steel and the zinc. This results in the creation of zinc-steel alloy, which is done by:
- First, cleaning the stainless steel with a sodium hydroxide solution to remove dirt, debris, oil, and other residues.
- An acidic solution is then used to remove any mill scale, rust, contaminants, and other surface impurities.
- Preventing oxidation is an essential feature of galvanisation, which is achieved by applying a zinc ammonium chloride cleaning agent. This solution remains on the steel, as it helps the zinc stick.
- Next, the stainless steel is dipped into a vat of molten zinc, liquified at an extremely high temperature.
- The steel remains in the vat until it reaches the same temperature as the hot zinc.
- After being removed from the vat, the stainless steel is rapidly cooled in a special tank.
Unlike hot dipping, electrolytic galvanising is a cold process. The difference is zinc particles are now used to create an organic solvent, which is then applied to the steel surface. This process causes a reaction between the substances that again produce zinc-steel alloy. When the solvent evaporates, the zinc component remains on the metal. However, compared to hot dipping, electro galvanising produces a thinner zinc layer.
Galvanising Before vs. After Manufacturing
The different techniques in galvanising can be applied either before or after manufacturing the actual wire mesh. The results are slightly different, which is why this debate exists. When galvanising occurs first, the metal is drawn down the desired diameter. The individual metal wires are coated with zinc and then woven or welded into screens. However, when it’s time to weld them together, the welding can burn the zinc layer off at the joints, necessitating the need to be galvanised again.
On the other hand, when fabrication comes first, pre-woven steel products are dipped into molten zinc or coated with a solvent. This ensures that the mesh screens retain their protective coating. However, it is a far more costly option, particularly if the mesh products are custom ordered and galvanised.
The process of galvanising stainless steel is often treated as a separate category in the wire mesh industry due to its specialised fabrication methods and widespread use for various applications. Despite the difference in techniques, wire mesh sheet is still a highly versatile product made even more valuable due to galvanisation.
Phoenix Reinforcing is one of the longest operating family-owned and operated businesses on the Sunshine Coast. We are a structural steel specialist based in Queensland, offering a full delivery service. Contact us whenever you need quality steel products delivered to your doorstep.