A METHOD FOR UNWINDING ROLLS OF WEB MATERIAL

摘要

A method and apparatus for unwinding a vertically oriented roll of web material (10) is disclosed. The roll (10) comprises a lower surface, an uppe r surface and a circumferential surface. The apparatus comprises: at least one drive element (100) adapted to rotate the vertically oriented roll, a sensor (160) adapted to measure a tension of the web, and a controller adapted to adjust a speed of the web according to the tension of the web. The method comprises steps of rotating the roll (10), determining a desired web tension , and adjusting the speed of the roll (10) according to the desired web tensio n.