Graphite Alloy Stops the Sparking and Arcing

Aug. 21, 2008
A company making metal fasteners added an electrostatic paint line that gave managers grief almost as soon as it began operating.

The line uses steel baskets to hold 100-lb loads of small metal parts in a caustic cleaning solution, take them through primer pretreatment, then through application of 360 Vdc for electrostatic painting. Finally the baskets travel through a 350°F curing oven. The baskets had to turn and tumble, so they hung from a conveyor on a stub axle. But this axle-to-basket connection also had to carry the voltage needed for painting.

Once in operation, the poor electrical contact between the axle and baskets, coupled with the relatively high voltage, led to arcing and sparking. It was intense enough to eat away at the metal components, including entire sections of overhead conveyor chain. To solve the problem, Graphite Metallizing Co., Yonkers, N.Y., recommended a Graphalloy bearing in a cast-iron housing. The graphite/metal alloy conducts electricity well, so the new part made for better current flow, which stopped the arcing. The bearing could also withstand the caustic detergent and high temperatures.

A graphite-metal alloy bearing in a cast-iron flange solved arcing problems on an electrostatic paint line.

Sponsored Recommendations

The entire spectrum of drive technology

June 5, 2024
Read exciting stories about all aspects of maxon drive technology in our magazine.


May 15, 2024
Production equipment is expensive and needs to be protected against input abnormalities such as voltage, current, frequency, and phase to stay online and in operation for the ...

Solenoid Valve Mechanics: Understanding Force Balance Equations

May 13, 2024
When evaluating a solenoid valve for a particular application, it is important to ensure that the valve can both remain in state and transition between its de-energized and fully...

Solenoid Valve Basics: What They Are, What They Do, and How They Work

May 13, 2024
A solenoid valve is an electromechanical device used to control the flow of a liquid or gas. It is comprised of two features: a solenoid and a valve. The solenoid is an electric...

Voice your opinion!

To join the conversation, and become an exclusive member of Machine Design, create an account today!