Net bag packing looks simple until you try to hit a steady output with one
operator. Onions, potatoes, garlic and citrus all behave differently in a hopper,
and the bag itself changes the whole calculation. Here is how to specify a
semi-automatic net bag packing machine so that it works on your line from the
first day instead of the fifth week.
Start from the bag, not the machine
Everything downstream follows the net bag you intend to sell. Write down three
numbers before you talk to any supplier:
- Bag width and length — measured flat, in millimetres. The filling head and
the closing head are both built around this. - Weight per bag — the finished, packed weight the customer sees. A machine
set up for 2 kg will not hold accuracy at 8 kg. - Bags per hour — the real target, not the theoretical maximum. One operator
handling filling and closing is usually the limiting factor.
Weighing or volumetric filling
A weighing head measures each portion, so bag weights stay consistent when the
produce varies in size — the usual case with onions and potatoes. A volumetric
head fills by volume, which is faster and cheaper but only holds accuracy when
the product is uniformly graded.
For export orders, where a short weight can cost you the shipment, weighing is
usually worth the extra cost.
The closing head decides your consumables
A semi-automatic net bag packer closes the bag either with a pneumatic clip head
or, on simpler machines, by leaving the bag for a separate clipping machine.
A pneumatic head that takes 506 or 711 aluminum clips means one machine does
the whole cycle — fill, weigh, close — with a foot pedal.
Choose 506 clips for standard net bags up to roughly 5 kg, and 711 clips where
the bag is thick, the load is heavy or the mesh is woven rather than extruded.
What to send us for an exact quotation
Send the bag size, the weight per bag, the bags per hour you need, and the
destination port. We will come back with a machine specification, the matching
clip or bag size, the packing dimensions and an FOB price within one working
day.