Background
A common question we receive from customers is:
"If this bag size works for manual packing, why does the automatic packaging machine require a larger bag?"
This question is reasonable-and very important to answer correctly.
Plastic Parts Behave Differently From Metal Parts
Plastic components are lighter than metal parts and have less inertia.
During automatic packing, this means plastic parts are more likely to:
Bounce after falling
Rotate or tilt inside the bag
Stack unevenly
These characteristics increase uncertainty after the product enters the bag.
Free-Fall Is Unavoidable in Automatic Packaging
In automatic counting and packaging machines, products fall freely into the bag after counting.
Unlike manual packing, the final position of the product inside the bag cannot be controlled.
As a result:
Parts may lie horizontally
Multiple parts may overlap
The position may change again before sealing
Heat Sealing Requires a Safety Zone
The sealing area must remain clear during the heat sealing process.
If the bag size is too compact, parts may enter the sealing zone, leading to:
Products being cut during sealing
Weak or incomplete seals
Increased machine stoppages
Why Increasing Bag Volume Is a Technical Decision
Increasing the bag size is not about convenience or excess material usage.
It is a risk-control decision based on machine testing and real production conditions.
A slightly larger bag allows:
Natural settling of products
Reduced interference with sealing jaws
Stable, continuous machine operation
Conclusion
In automatic packaging, a bag that "just fits" is often not safe enough.
A properly sized bag ensures product protection, sealing reliability, and long-term production stability.
