A method for operating webfed printing presses producing printed products, includes providing a reel stand and printing units. A flying web change from first to a second webs takes place with production of a splice, and settings are made on printing units coordinating with passage of the splice through the press. At least two printing units are configured as double printing units for flexographic printing and operated for producing printed products. Each double printing unit includes first and second partial printing units, and first or second partial printing units are activated or deactivated according to passage of the splice through the press, or a switchover occurs from first to second partial printing units of the double printing unit, or vice versa. The flexographic printing press is operable nonstop and automatically during web change. When operating a web-processing rotary printing press for flexographic printing, automation, productivity and print quality increases.

The present invention relates to an inversion transfer module (60) for a converting machine having a printing module (16) comprising a first printing unit (17) arranged to print on a top side (S1) of the sheet (1), and a second printing unit (17) arranged to print a bottom side (S2) of the sheet. The inversion transfer module is arranged between the first printing unit and the second printing unit and comprises a first inversion vacuum transfer (62) arranged to contact the first side of the sheet and a second inversion vacuum transfer (64) configured to contact the second side of the sheet, whereby the inversion transfer module is configured to change the side of adherence and transportation of the sheet.

The present invention relates to an inversion transfer module (60) for a converting machine having a printing module (16) comprising a first printing unit (17) arranged to print on a top side (S1) of the sheet (1), and a second printing unit (17) arranged to print a bottom side (S2) of the sheet. The inversion transfer module is arranged between the first printing unit and the second printing unit and comprises a first inversion vacuum transfer (62) arranged to contact the first side of the sheet and a second inversion vacuum transfer (64) configured to contact the second side of the sheet, whereby the inversion transfer module is configured to change the side of adherence and transportation of the sheet.