Finishers' Management Article - January 2001

Are You Ready to Tumble?

Alex Guzman, processing manager at South Bay Operations in Torrance, CA, knew his company needed to keep its plating technology current in order to remain competitive in the market. South Bay, which employees over 1,000 workers and bills over $10 million per month from its cadmium, silver and nickel plating, was using a manual barrel plater for its processes.

When he began looking into upgrading to an automatic plating line, Guzman ran into a problem: The shop had a limited amount of floor space and the conventional automatic lines he was looking at were too large to fit. After meeting with several suppliers, Guzman finally found a machine that could not only solve his problem, but had the technological changes he was looking for: Technic Equipment Division's Tumbleplater®.

An Overview
Technic Equipment Division, based in Pawtucket, RI, has spent several years developing an alternative bulk-plating system, which is entirely automatic. The system can handle almost all of the application currently being barrel plating, including gold, silver, cadmium, copper, nickel, zinc, chromating and cleaning. Parts begin the plating process at the automatic load station then move on to cleaning, plating and unloading. In addition, conveyors can be added to the end of the line to transport parts to other processes or packaging.

The hoists and superstructure of a barrel line are completely eliminated. This reduces floor space and height requirements. The barrels are replaced by a series of compartments, one in each station, and instead of the parts moving from station to station inside a barrel, they are conveyed from one tumbler to another. The dragout reductions arising out of part-only transfer from station to station reduces the number of rinse stations required and, consequently, the length of the line. Automatic loading from tote and unloading to tote or final packaging also allows more efficient use of space, while the capability to dry as part of the automation process eliminates the need for a separate process step.

While these features prompted Guzman to buy two systems, he realized other benefits from the purchase.

Increased Production
The plating speed of the system is increased, which is due to several factors. The first is the quantity and placement of anodes. Anodes are placed on the side of the tumbler as well as the front. The front anodes have the advantage of a direct line of sight to the parts being plated, which coupled with solution agitation allows for higher current density. According to Tony Guglielmo of Technic, conventional barrel platers usually have anodes on two sides only and virtually never have a direct line of sight to the parts due the enclosed design of conventional barrels. Another factor is maintaining the maximum efficiency of a particular plating bath. Barrels aren’t noted for good solution transfer and, therefore, the metal in the barrel plates down and plating speed, as well as efficiency, drops. In the Tumbleplater, a sparger pump is used to keep a constant level of electrolyte around the parts being plated so the efficiency of the bath remains at its maximum. With these advantages, the system can plate up to 30 percent faster than traditional barrel platers. This makes it act more like a rack plating process and results in greater deposit uniformity. In some cases, parts that are normally plated on a rack can be plated in the Tumbleplater.

Reduced Dragout
Without a barrel being transferred, the most significant contributor to dragout is removed. The system provides the additional capability for spray rinsing prior to part transfer to the next station. This reduced dragout translates into less chemical and water usage, and, therefore, reduction in waste treatment costs and exposure.

Reduced Maintenance
According to Guzman, the absence of overhead barrels and conveyors in the system has significantly reduced the amount of maintenance required to maintain them. In fact, the systems at South Bay have operated for 24 hours a day, seven days a week for two years with only minor maintenance required. Also, because the Tumbleplater is automatic with all of the plating steps programmed into the system, the demand for operators is reduced.

In Closing
Guzman has been using the system for two years and has yet to experience significant problems. In addition to the limited amount of floor space required, the Tumbleplater’s benefits have made it a profitable purchase choice for South Bay.

“The Tumbleplater has more than met our expectations,” Guzman said. “We have increased our production, reduced the dragout from solutions by 80 percent, and have reduced maintenance.”