Functions of barrel platng
1.The primary function of barrel plating is to provide an economical means to electroplate manufactured parts that also meets the customers specific finishing requirements.
2.The four most important requirements are:Engineering applications,such as building up the thickness of metal to change the physical size of a part or to provide a good surface for some other treatment such as painting or screening.Decorative coatings such as Bright Nickel,Brass,and Antiquing.Cosmetic uses such as Zine plating to improve shelf life and saleability.But by far the most important use of barrel plating is to extend the corrosion protection of the customers' parts.

Which parts shoule be barrel plated and why?
1.Barrel plating can accommodate a wide variety of shapes and sizes as well as different metals and alloys.These parts can then be plated in an equally diverse amount of plating baths each with their own properties and formulations.
2.Generally any part that can fit throuth the opening in the barrel can be plated provided good procedures are maintained,excepting long&thin parts.
3.The quality of the finish can equal that of still or rack plating and is usually more economical.
4.Typically parts weighing 5# or less or having a volume of 125 less can be routinely barrel plated.
5.The rotation of the barrel and the parts within it lend themselves to other advantages.The mechanical energy of the rotation produces a burnishing action that helps to clean and descale the parts to a greater degree than rack plating,much the same as wringing your hands under the water faucel facilitates the speedier removal of soils and dirt from them.
6.The tumbling action is also responsible for the high degree of plating uniformity which can be achieved in the barrel.As the parts move they make and break electrical contact creating what is called a bi-polar effect whose net benefit is the evening out of the high and low areas which coule pose enormous problems if the same parts were to be racked and finished.It is foe this resson that fasteners are almost exclusively plated in barrels.For this reason,as well as economics.


Process of alkaline zine plating + passivation for fastener
Loading → Hot Degreasing → Water Rinse → Electrolytic Degreasing → Water Rinse → Acid pickling → Water → Rinse → Electrolytic → Degreasing → Water Rinse → Neutralization → Water Rinse → Pre-dip → Zinc Plating → Nitric Acid → Water Rinse → Passivation → Water Rinse → Top → Coating → Unloading