The new zinc arc spray booth is located in workshop 10 following its change
of use from a fabrication shop to a finishing and assembly shop. This has
enabled BoA to offer alternative corrosion protection to Galvanising. This is
because the protection properties of both Galvanising and Zinc Arc Spraying are
similar with both processes creating a porous coating on the workpiece. Such as
spray zinc wire and other products.
The two processes differ in the way in which the zinc is applied. Zinc Arc
Spraying requires the workpiece to be shot blast to an SA 3 grade which provides
an adequate surface for the zinc to adhere to. After shot blasting the zinc
protective coating can be applied, this process involves two zinc wires being
fed into a pistol which get electrically charged, one positive and one negative.
The wires are forced together which forms an electric arc, melting the wire.
Compressed air is then passed through a nozzle which atomises the molten metal
and sprays it onto the workpiece. Upon contact, the particles flatten onto the
surface, freeze and mechanically bond, firstly onto the workpiece and then onto
each other as the coating thickness increases. The zinc sprayed surface can then
be wet sprayed to give a sealed decorative finish.
Since you know the process of manufacturing spray zinc wire, you may know
more about it.
