A Saturno six colour flexo printing machine with central drum was recently delivered by BFM to a bag manufacturer in Tanzania. The machine, supplied together with a complete production line, also comprising an upstream extruder and a downstream welding machine, incorporates semiautomatic gear technology which ensures high-quality printing performance thanks to high-definition photopolymer clichés and anilox rollers with wide scorings. This machine can process HDPE, LDPE, PP, BOPP, PVC and PET films, reaching throughput speeds of up to 200 m/min.
The printing units are equipped with simultaneous fast feeding, additional independent micrometric adjustment and automatic hydraulic locking and they use alcohol or water-based inks, which, thanks to chamber-type doctor blades, are evenly distributed over the whole width of the print area without affecting the colour shades. The ink, driven by an air pump through special channels, reaches the doctor blade and is spread onto the anilox roller. The latter, in turn, transfers the ink to the cliché, which then imprints it on the film. By means of a manual device, it is possible to adjust the distances between the anilox roller, cliché and film. The 1400 mm diameter central drum ensures perfect length and cross-wise calibration of the film.
The standard version of this machine includes drying of the print through an electric heating system with resistors of 5.5 kW, but it can also be equipped with a gas heating system complete with a burner and electric fans, particularly useful in countries where gas costs less than electricity. Thanks to an input and output automatic film guide it is possible to, respectively, insert the semi-finished product to be printed in the central drum positioned for correct alignment with the clichés and obtain a reel with edges perfectly aligned with the borders. An automatic turret winder on the exit side of the machine delivers reels with diameters of 800 or 1000 mm. Finally, reel change with automatic cutting is carried out without stopping the machine.