METHOD AND UNIT FOR FORMING TUBULAR LENGTH OF WEB MATERIAL IN LABELLING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a method and unit for forming tubular lengths of web material.SOLUTION: A method for forming tubular lengths of web material, comprises the steps of: winding part of a web material in a tubular configuration such that opposite vertical both ends 34 of a linear portion overlap; and welding the overlapping both ends 2 to fix the linear portion 2 of the web material in sleeve configuration, the step comprising the steps of: heating up to a first temperature a first region R' of the linear portion 2 over the whole of which both ends 34 overlap; and heating up to a second temperature T2 lower than the first temperature a second region of the linear portion 2 adjacent to the first region R', the ends 34 of the portion 2 of labelling web material overlapping over only a part of the second region.