Pre-made bags and roll film are both flexible packaging materials. The main difference is that pre-made bags are finished, separate packaging bags, while roll film is an unprocessed roll of base packaging material.
Form and finished state
Pre-made bags
They have already been cut and bottom-sealed. Common styles include three-side seal, center seal, and stand-up pouches. They have a heat-sealable opening and are individual packaging units that can be filled directly.
Sizes are fixed. Some have hanging holes, zippers, or other added features. They work with manual sealers or small semi-automatic sealing machines.
Roll film
It is a continuous roll. It has not been cut or sealed and is only a base packaging film. It has no separate packaging unit.
Width and length can be customized for packaging equipment. It is usually stored and shipped in large rolls, which makes continuous feeding easy for automatic packaging machines.
Use process and application scenarios
Pre-made bags suit small-batch, multi-spec, scattered packaging. Examples include manual snack packing and small hardware parts. Operators fill the bag and heat seal the opening with a sealer. No additional bag-making equipment is needed.
Roll film suits large-batch automatic packaging, such as food production lines and daily chemical packaging. It needs a vertical form fill seal machine, pillow packaging machine, or similar equipment. Bag making, filling, heat sealing, and cutting are completed in the packaging process.
Material adjustment requirements
Pre-made bags
The composite film orientation and heat seal layer are already processed before delivery. Heat sealing temperature and pressure parameters are fixed. They work directly with the matching sealing machine and need no extra adjustment.
Roll film
It can use single-layer PE, composite film, and other base materials. Before use, confirm the heat seal layer faces the equipment feed direction. Adjust heat sealing temperature, packaging speed, and heat sealing pressure according to the packaging machine parameters to avoid poor sealing or bag breakage.
If non-standard parts such as heat sealing cutter holders, guide rollers, or bag forming parts need to be machined to site dimensions, we can custom machine them according to customer drawings. Hansheng Automation supports single-piece and small-batch delivery.
Our custom precision parts machining capability is not limited to packaging machinery. In addition to filling machinery parts, tobacco packaging machinery parts, ceramic machinery parts, yacht precision parts, and RC car precision parts, Hansheng Automation can machine non-standard parts for printing machinery, food machinery, and medical devices according to drawings. We support drawing-based customization and small-batch delivery.
