AKRON—Troester GmbH & Co. K.G. is beginning to market its new machine intended to help solve the problem of electrostatic charge from tires made with silica.
The Troester CoEx 5plus1 allows multiple extrusion aggregates and has been available in Asia and Europe for a couple of years, but only now is it being actively marketed to North American customers, according to Dennis Preick, with Troester GmbH's rubber machinery development department.
Preick and Michael Neubauer, president and CEO of Cuyahoga Falls, Ohio-based Troester Machinery Ltd., showed off the equipment at the International Tire Exhibition & Conference.
The CoEx 5plus1 is based on Troester's “Xplus1” technology, a newly designed upper part of a piggy-back head with an additional extruder. When used with silica compounds, Troester said a carbon black compound is added into the tread to ensure the discharge of static energy from the tire.
“With modern tread compounds, the amount of silica has increased,” Neubauer said. “When the amount of silica becomes more and more, you always have the problem that the electrostatic loading from the car cannot be handed over to the street. If you go to gas station, you have the risk of electrostatic loading causing a fire in the car. This allows you to avoid electrostatic loading on the car.”
The new machinery enables the multiple extrusion of up to six different compounds, especially beneficial when producing ultra-high performance and maximum performance tires. For these tire lines, Neubauer said it is necessary for multiple compounds to bring different performance attributes to the tire.
“As the tire and tread become more complicated, you can adapt a little bit different compound properties to the requirements,” he said. “That's why you need five extruders when before you only needed four.”
When using silica compounds, the problem of reduced conductivity is solved by the 5plus1 with an additional extruder that adds a narrow component with a conductive carbon black compound to the tread. The “chimney” component reaches from the upside to the bottom of the tread to discharge the static energy from the tire.
Troester's “Xplus1” technology allows for the use of existing tooling, the firm said, without the need to change its design. Only adaptation to overlapping pieces is needed.
The machinery firm makes the 5plus1 at its German headquarters and thus far has gotten good reviews on it, Preick said. “It's working quite fine. It's easy to access, easy to maintain, easy to clean and has short changeover times.”