Cold process: there is no distortion on fabricated parts. Complicated structures like trusses, towers and bridge members can be given this treatment without fear of warpage.
Any size or shape: unlike dipping, which is restricted by the size of the bath, in spraying their is no limit to the dimensions of the part to be coated
Site jobs possible: spraying can be carried out at site, unlike in dipping, where the part has to be taken to the place where the zinc bath is available
Ideal surface for painting: spraying leaves a rough surface which is excellent for painting. Dipped surfaces are smooth and paint, if applied, often peels off
Wide range of coating thickness: coating thickness can be accurately controlled from a minimum of 50 microns to a millimetre, depending on the protection required
Better surface preparation: Blasting, which is a prerequisite for spraying, removes all traces of oxides and exposes the base metal. Dipping, which is done after pickling, sometimes results in the link layer peeling off due to excess of acid or alkali
Localized repair possible: On site repair can be carried out to damaged portions both at ground level and in erected condition
Pure zinc coating: spraying assures a 99.95% pure zinc coating unlike in dipping where the initially pure bath gradually gets contaminated by iron. This iron can get deposited on the job and acts as a corrosion accelerator
No hydrogen embrittlement: pickling, which is necessary for dipping, results in hydrogen liberation. This gas can get entrapped between the steel and the zinc causing embrittlement and making it unsafe for working loads
Dross embedment avoided: in dipping, dross, which is present at the top of the molten zinc bath, gets embedded between the iron and zinc resulting in peeling of the coating
Excellent high friction grip: spraying maintains the efficiency of friction grip bolts and ensures their effectiveness throughout the life of the structure