Increasing accuracy of web tension systems with contact-free control

摘要

With increased reel/roll sizes, more web layers and higher speeds being required from printing and processing machinery, integrated contact-free tension control systems are becoming the industry standard, says David Morgan of ZF Industrial. A combination of EBU brakes and EKU hysteresis clutches managed by ZF's ERM controllers has proven to have the accuracy and reliability to successfully replace DC drive based tension control systems in three high precision presses at Day International (UK). The company manufactures rubber sheeting used for producing newspapers and banknotes in high-speed printing presses - a process which primarily involves attaching a layer of rubber, to a fabric backing. After considering a manual clutch system to replace increasingly high maintenance inverters, the company's engineers rejected the idea due to risks of contamination from dust particles, a problem conveniently avoided by the magnetic non-contact operation of the hysteresis units.