The electroplating barrels are intended for coating of small parts in bulk. This type of treatment enables to reduce much the complexity due to the mounting/demounting of parts, which decreases the overall production costs. The coating in the rotating barrel ensures the uniform coating. The polypropylene barrels are used for the majority of processes, and the temperature of the working solutions may reach +80 °C. For some chemical coatings, the stainless steel barrels, characterized by high abrasion resistance, are used.

First patent No. 2122606 for "Barrel for electroplating of parts" was obtained in 1994.

Design of the electroplating barrels

The electroplating barrel, manufactured by Poliplast, is made, as a rule, in the form of a hexagonal prism. At the end faces, the barrel has gears intended to put the barrel in motion. The faces of the prism are fastened to the gears with strong ties, made of polypropylene or titanium, depending on the length of the barrel. On one of the faces there are removable lids, through which the treated parts are loaded/ unloaded. The barrel's sections have perforation holes and an embossed inner surface, which prevents flat parts from sticking on them. In some models, the internal space is divided into sections with a partition. The size of the perforation holes is 1x1 mm or 2.8x2.8 mm.

The electroplating barrels are installed in carriages of various designs. The frame is a basis of the barrel carriage structure. To drive the barrel, the gear motor, which transmits the movement to the product through a system of gears, is provided in the carriage. The portable barrel carriage is moved by a telpher or a transporter. The cathodes for electrochemical treatment of parts are introduced into the barrel through tubular semi-axles.

The principle of using the electroplating barrels is as follows. The barrel is filled with parts to be treated, after which the carriage with the barrel is moved through the electroplating tanks to the tank for treatment in accordance with the process. When installing the carriage in the tank, the gear motor, rotating the barrel, is powered through the current supply of the tank. In terms of the uniformity of the electrochemical coating, the optimum speed is 9-15 rpm. In the tanks of electrochemical coatings, the rectifier current is supplied to the cathodes through the current-carrying tank catchers. The quality of the coating is also affected by the loading of the barrel with parts by volume; the optimum loading is 25-35%.

When operating the barrels, the following specific features should be taken into consideration:

• Due to intensive stirring of parts, there is a risk of damage to the thin faces and surface of the relief of the workpieces due to mutual friction of the elements.
• Due to the contact of treated parts with each other, some part of the deposited metal is erased.
• The coating is not applied evenly enough on flat parts that are difficult to stir in the barrel.