Plastic Bag Making Machine

Overview

A plastic bag making machine converts a roll of tubular or folded film into finished bags by sealing and cutting it to length, with optional stations that add perforations and punched handles. It sits at the end of the film line, after the film is blown and printed, and turns the web into the bags themselves: shopping bags, bread bags, garbage liners, produce rolls, and courier mailers. Film unwinds at the Plastic Bag Making Machine's Film Unwind Unit, indexes through the Feed Roller Section, and is welded and cut at the Seal & Cut Unit before the Conveyor & Stacker collates the output.

The machine runs intermittently: the film stops for the seal-and-cut, then the servo feed indexes one bag length, so the seal dwell and feed length together cap the rate.

How it works

The Feed Roller Section pull the film forward exactly one bag length per cycle, reading the print mark with a photocell so each cut lands on register. With the film stopped, the Seal & Cut Unit drops its heated bar to weld the seam while an integral knife severs the bag to length; a thermocouple holds the bar at setpoint so the weld is consistent.

Optional inline stations add features as the film indexes: the Perforation Unit nips a tear line between bags on roll and star-seal products, and the Handle Punch Unit dies out the carry handle or a hang hole. Finished bags pass onto the Conveyor & Stacker, where a counter tallies them and the stacker collates a set count into a pile for bundling. The Servo Control System coordinates the feed servo, seal timing, perforation, and punch into one cycle and runs the touchscreen where bag length, seal temperature, and speed are set.