Abstract: A unit configured to form a tube for producing sealed packages starting from a sheet of packaging material having opening devices pre-applied thereon, comprises at least one guiding assembly configured to interact with the sheet of packaging material to fold it gradually into a tube shape; the guiding assembly comprises a plurality of folding rollers delimiting a passage for the sheet of packaging material and each having a lateral wall configured to cooperate in contact with the sheet of packaging material to control the folding thereof; the folding rollers comprise at least one folding roller having at least one recess on the lateral wall thereof, the recess defining a slot configured to be engaged by the opening devices.

Abstract: The method for splicing together first (10) and second (20) webs of pre-creased laminated packaging material for manufacturing sealed packages of pourable food products in a form, fill and seal type packaging machine, includes the steps of holding an end portion (18) of a first web (10), with its inner surface (14) oriented in a predetermined direction. An end portion (28) of a second web (20) is cut to form an undercut surface (29). The undercut surface (29) of the second web (20) is superimposed onto the end portion (18) of the first web (10), with the outer surface (27) of the second web (20) in contact with the inner surface (14) of the first web (10). The undercut surface (29) of the second web (20) is then bonded to the end portion (18) of said first web (10). At the splice (30), the inner surface (14) of the first web (10) and the inner surface (24) of the second web (20) together define an integral, continuous inner surface (14, 24).