A Study on the Slippage between a Moving Web and a Roller

이송중인 웹과 롤러의 슬립에 관한 연구

Air entrainment can become a significant problem in a web handling process. The development of air film between a web and an idle roller can cause a reduction of traction and traction coefficient, by which a slip is occurrred. Computational and experimental study was carried out to describe the slippage of an idle roller for given operating conditions, tension and web velocity. An extended mathematical model to find out a slip condition was developed by using the models of air film height, dynamic traction coefficient, and torque balance of a rotational roller. And by using the extended model, a mechanism to define the slippage between the roller and the moving web was suggested. The results of simulation and experiment showed that the extended dynamic model could properly characterize the rotational motion of the idle roller by considering dynamic traction coefficient. By examining the rotational motion of the idle roller with web dynamics(speed), the mechanism to define al slip condition between the roller and the web was found to be effective.