With a random incoming axial stream of pallets of articles, there is a stack of blanks, an axial stream synchronized with pallets is formed, all of the pallets are transferred from the axial stream synchronized with pallets to constitute an axial stream that is synchronized with lots, lots are separated by empty spaces having length of one or more article lengths, whereby the spacing is thus variable and adapted to lot length, blanks are unstacked upon demand based on the pallets to constitute a synchronized stream of blanks corresponding to the stream synchronized with lots. Blanks are separated by empty spaces with length of one or more article lengths, starting from the stream synchronized with lots and the stream synchronized with blanks; each lot of articles is made to work with each blank before the blank is folded around the lot of articles and made into a single unit.