The Two Classes of Bulk Bag Fillers
There are two classes of bulk bag fillers: suspended “hanging” style fillers and bottom supported “platform” style fillers. Either style can be designed with a gross weigh (fill and weigh simultaneously) or net weigh (pre-weigh and fill as a secondary step) type of weighing scale. Most bulk bag fillers are fed by either a gravity flow gate (ex. slide-gate or butterfly valve), rotary valve or an auger feeder.
The Advantages of Bulk Bags
Bulk bags offer several advantages over other types of packaging. They improve plant safety by reducing the amount of physical handling required to load and unload the packaged material since they are designed to be moved by mechanical means (fork truck, pallet jack, or hoist).
Bulk bags are frequently used as storage silos, day bins for short term storage and intermediate hoppers in product processing systems.
Bulk bags or FIBCs (Flexible Intermediate Bulk Containers) are large woven polypropylene bags capable of storing and transporting the heavy loads of dry flowable bulk materials weighing up to 4,000 lb. (1,818 KG). Bulk bags are designed to take a high amount of abuse that would quickly destroy other types of packaging. There are several bag designs available: spout top, duffel top or open top and flat bottom, discharge spout or port-hole bottom. Bag Style selection will depend on the requirements of the application.
The operating cost per container is typically reduced when bulk bags are used. Filling, lifting, opening, dumping, and disposal of forty, 50-lb paper bags is in most cases more costly and time consuming than positioning and opening one single 2000-lb. bulk bag. Bulk bags can also be handled, transported and stored without pallets because integrated lifting loops are built into the upper corners of each bag further adding to cost savings and reducing the disposal costs of used packaging materials.
Additionally, bag capacity increases, the empty bag weight as a percentage of bulk material weight transported decreases. This means more material can be shipped with less packaging for the same cost. Bulk bags can also be positioned and stacked more efficiently to heights exceeding that of smaller bags, maximizing shipping container usage and storage facility space.