Method, mandrel and apparatus for winding up and removing coreless rolls of stretch film

A method for winding up and removing one or a plurality of coreless rolls of a stretchable plastic film on a mandrel comprising a tubular body having a peripheral wall provided with a plurality of perforations or holes, in which said wall extends longitudinally from a rear to a fore end of the mandrel, and means for supplying pressurized air in the tubular body of the mandrel and out through the holes during removal of the roll or rolls,

• wherein at least one roll or a plurality of rolls of the stretchable plastic film are wound up on said perforated zones of the mandrel,
• comprising the steps of:
• providing the tubular body of the mandrel with at least a first fore air chamber and a second rear air chamber, axially aligned, at respective fore and rear perforated zones of the peripheral wall of the mandrel;
• connecting the air chambers of the mandrel to a pressurized air source by a duct system comprising selectively actuable control valves;
• removing the roll or the plurality of rolls, by initially supplying pressurized air in all the air chambers of the mandrel during a first removal step of the roll or rolls;
• and
• subsequently selectively disconnecting each single air chamber from the pressurized air source during a second removal step of the roll or rolls, starting from the rear air chamber (15), towards the fore air chamber of the mandrel.