Processing Technologies LLC, a maker of sheet extrusion machinery in Aurora, Ill., has been granted a U.S. patent for a new roll skewing mechanism that compensates for roll deflection that happens in sheet roll stands.
U.S. patent 9,182,067 was granted to PTi President Dana Hanson and colleague Mitchell Gritzner. The company offers the skewing mechanism as an option for all of its roll stands.
The device mitigates the impact of chrome roll deflection, and permits the production of thin-gauge sheet with more-uniform thickness.
According to PTi, high nipping loads across the entire width of the roll face can cause the roll to deflect, resulting in a thick band at the center of the sheet. “This new invention gives processors the ability to produce thin-gauge sheet that is uniform in thickness and enables them to reach thicknesses that were previously unattainable,” said Sushant Jain, the company's senior scientist.
The roll skewing mechanism uses a cross-axis positioning of the roll so that the roll deflection is wrapped about the mating roll, creating a uniform gap over a wide operating range. The company said the highly versatile system is recommended for processing thin-gauge materials such as polypropylene, because of its adjustability over a wide range of deflection patterns and sheet gauge targets.
At K 2016 in Düsseldorf, Germany, PTi Processing Technologies LLC is exhibiting at Hall 13, Booth B91.