Paper web width adjusting method for printing system with multiple printing steps - using water for wetting and with at least one step for applying pressure force on side surface of web to form wavy surface causing width redn.

摘要

The width of the paper web (W) can be adjusted, so that a pattern printed in a preceding printing step, can be matched with the pattern formed in a successive printing step. At least one step is provided for applying a counter pressure on the other side surface of the paper web (W). A pressure system includes a number of pressure sections. A web width adjusting unit (20) has a pressure force application unit (1) with a number of control rollers (1a-1f). An automatic control unit (4) has an input unit (4a) eg a keyboard and a prim. detector unit (4b) for differing drive data and determines displacement of pattern on paper web. USE/ADVANTAGE - Lithographic colour printing system. Improved matching and alignment of successive image and line patterns and can adjust width of web to suit.