Bag sealing machines are made to seal various kinds of pre-made bags or pouches. Bags can be sealed using impulse heat, hot melt glue, hot air (to re-activate pre-applied glue), thread stitching, or many other bag sealing methods. Depending on the bag sealer machine, the bag may have the opening of the bag folded over prior to sealing.

Bag sealers can be designated as semi-automatic or automatic. The machine you see above is the semi-automatic type of bag sealer. This type of machine requires the operator to present the bag to the machine in the proper orientation. Once that is done the machine literally drags the bag into the machine to complete the sealing process. This machine uses both heat and pressure to seal the top edge of the bag. This machine uses two parallel facing heat seal bands to simultaneously apply both heat and pressure while the pinch pressure between the two belts drags the bag through to the other side.