5 Types of Packaging Equipment for Valve Bags
There are five basic types of valve bag-filling machines: auger, impeller, air, gravity, and vacuum. Each type performs the same basic task of putting the product into the bag. Bag packer machines range in size, speed, output, and automation level.

Auger
Auger packers utilize a horizontal screw to convey product from a supply hopper through the fill spout and into the bag. The screw is powered by a drive shaft that turns the screw. This type of valve-bagging machine is ideal for cake-like powders, flakes, and granular products.
In general, auger-style bag-filling equipment packs bags slower than impeller or air-packing equipment.
Impeller
Impeller packers use a multi-blade vertical or horizontal impeller to convey the product into a bag. The product flows by gravity from the supply hopper into the product feed inlet at the top of the machine. When a fill cycle is initiated, the impeller creates a positive draw on the product moving it through the feeder and into the bag.
The impeller packer is designed for maximum efficiency by entraining less air, which results in faster filling rates and smaller-sized bags.
Air
Air packers, sometimes called forced flow or pneumatic packers, are high-speed, gross-weight baggers that blow fluidized material into valve bags. The air packer offers both excellent weight accuracy and simple operation. Air packers provide for high filling rates and minimal strain on a bag.
Gravity
Gravity packers utilize gravity alone to draw product from a supply hopper through a funnel and into the bag. This style of valve bag packaging machine is the most cost-effective but the least efficient. Most gravity-packing equipment systems do not require a power source.
Vacuum
Vacuum packers use negative pressure to draw material into the valve bag. Bags are placed in a vacuum chamber where the product is effectively sucked into the bag. This style of valve bagger system is typically only used for light ultra-fine products such as carbon black, fumed silica, and graphite.
Fill rates are fast and accurate, but the time to place bags into the chamber (“clamshell”) can be slow.
Valve Bag Filling Machine Automation
Valve bagging equipment can range from labor-intensive manual setups to state-of-the-art fully automatic pack lines.
Manual: With a manual bag-filling machine, the operator places the bag on the fill spout and pulls the filled bag off by hand. From there, the filled bag is palletized.
Semi-Automated: The operator places the bag on the fill spout by hand. A valve bag packer machine discharges the filled bag onto a conveyor where it is palletized.
Fully Automated: A bag filler machine places the bag on the fill spout and discharges the filled bag onto a conveyor. The bags are then palletized via robot.