Wire mesh is typically coated in either PVC or by galvanizing processes in order to improve its physical properties and broaden the range of applications for which it can be used.
Mesh used for galvanizing purposes is typically made from iron or steel, which is welded or woven together vertically and horizontally to create woven wire mesh. Starting with a strong metal ensures the structural soundness of the finished product, and the process of galvanizing further strengthens the wires, making them resistant to rust and reactions with the elements, such as extreme temperatures or weather.
Products such as fences, animal cages, filter screens, fish traps, tree guards and concrete reinforcing frames are commonly made from galvanized wire mesh. It is an economical alternative to using stainless steel mesh in industrial, agricultural and residential applications and provides many of the same features that stainless steel mesh is chosen for.
Hot dipping or electrolytic reaction are the two methods most commonly used to galvanize iron or steel wire. During hot dripping, the mesh is dipped into extremely hot molten zinc. A zinc-iron or zinc-steel alloy is formed by the reaction of zinc with the wire and this covers the surface of the mesh with a strong and protective coating. The electrolytic process is a cold process that used an organic solvent of zinc particles and paints the mesh surface. The solvent then evaporates leaving the zinc particles on the metal where the reaction between the two results in a coating.
The wire mesh can be galvanized before or after it is welded or woven into its final structure. Most manufacturers however choose GAW (galvanized after welding) mesh as it provides protection even around the intersection of the wires and ensures coverage against exposure to corrosion. Galvanizing the mesh after welding also strengthens the crossover of the wires and ensures the longevity of the weave. However GBW (galvanized before welding) methods are also commonly used as the wire mesh can then be constructed into any shape and adjusted to specific needs. Galvanized wire mesh is typically stored in rolls of varying heights and widths and is then cut to the desired dimensions. Items such as cages or traps will then be welded into their finished shapes.