5 Basic Types of Valve Bag Filling Machines Explained

October 18, 2023

In the world of packaging and bulk material handling, valve bag-filling machines play a crucial role in efficiently packaging a wide range of products. 

This blog explores the five basic types of valve bag-filling machines, providing a comprehensive understanding of their functions and applications. Discover how these machines work and which one may suit your packaging requirements best.


What Is a Valve Bag?

A valve bag, also called a pasted valve stepped end (PVSE) bag, is a common industrial packaging style designed to package a wide variety of dry, flowable products. Valve bags can be made from paper, polyethylene film, or woven polypropylene.

These bags are packed on equipment that deposits material into the bag via a horizontal filling spout. Their construction results in a squared-up bag, which palletizes very securely and can be printed with product information on the side or end panels for easier product identification in pallet loads. 

What Types of Products Can Be Filled Into Valve Bags? 

Valve bags are ideal for quickly and efficiently packing dry products that flow. Common valve packing materials include:

common valve packing materials

How Is a Valve Bag Filled? 

Valve bags are filled through an opening located in the top corner of the bag. The product is pumped or forced into the bag via gravity, air pressure, impeller, or auger. When the bag is discharged from the packing equipment, forces generated by the product inside the bag allow the valve opening to self-seal. 

Additionally, valve bags can be equipped with different valve or “sleeve” types. Common sleeve types include:

  • Paper Insert
  • Poly Lock
  • Tuck-In
  • Sonic Seal

Each sleeve type performs the same basic function. However, the proper sleeve type for your product and valve bag filler equipment needs to be evaluated when designing your bags.


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. 5 Basic Types of Valve Bag Filling Machines Explained-01


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 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 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 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 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.5 Basic Types of Valve Bag Filling Machines Explained-02

  • 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.


Partner With a Trusted Distributor for Your Valve Bag Needs

Whether you're in the agricultural, chemical, or food industry, making an informed decision about the right valve bag filling machine is pivotal to your packaging efficiency and product integrity.

At Southern Packaging, we know your materials demand the best bulk packaging supplies. Our team is dedicated to providing solutions tailored to your unique requirements so you can streamline your packaging process and ensure the success of your operations.

Connect with us today to explore the ideal valve bag-filling machine for your business needs and experience the difference of partnering with a trusted distributor.

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