New designs in food packaging are constantly being developed and introduced to consumers. While these new trends are sharp and eye-catching, product nevertheless needs to get inside – and that can be tricky at times with smaller openings and different packaging sizes.
Many of these newer package designs are still filled using a vertical form-fill-seal (VFFS) bag machine and auger filler. For food manufacturers and packagers, these machines are a major purchase that can take months to accurately specify, quote, build and deliver. The process can become easier by improving communication between the vendors and customer early in the design stages. This will make that process a much quicker and smoother experience for everyone involved – and deliver an FFS machine that’s ready for action the first day it’s installed.
One of the main components of the design process is the integration of the VFFS machine to an auger filler. These two pieces of equipment need to be in-sync with one another to properly deliver the desired performance for the customer’s application.
To get started, the vendors and customer need to share basic information with each other including:
- What is the product being filled?
- What is the density?
- What are the flow characteristics?
- What is the bag size?
- What is the bag style?
- What is the desired fill rate per minute?
- What is the target product weight?
- What is the ID of the forming tube?
Knowing this information upfront helps vendors determine the scope of the project. It also allows the auger filler supplier to determine if the customer’s desired performance specifications for the application can be achieved.
The reason to have answers to these questions in the early stages is that each one influences the other; if one of the answers to a question is unknown, it can change the scope of the project.
The size and shape of the forming tube is one of the most important pieces of information a filler vendor needs in designing a system to integrate with an FFS machine. The amount and speed of which the product can be filled depends largely on the diameter of the auger, and that is dictated by the diameter and shape of the forming tube.
Simple physics comes into play in determining the fill rate. Obviously the larger the forming tube, the more product that can be dispensed in a single auger revolution. For example, an auger that is 2 ½ inches in diameter delivers 12.27 cubic inches of product per revolution, whereas an auger that’s just a half inch larger in diameter delivers 24.74 cubic inches of product per revolution –twice as much. The size of the forming tube is of great interest to the filling machine vendor because the company wants to know how much space it has to work with inside that tube. Knowing this up front allows the supplier to determine if the specified speed can be met for the designed pouch size. If it does not, either the bag needs to be redesigned to a larger size or speed requirements must be reduced.
It is also important to review the flow characteristics for each product to be filled. In general, products are free flow or non-free flow, and each requires a different tooling setup. In some cases products can be a little of both, and the result is anything from an occasional drip to a steady stream of product flowing after the auger has completed its cycle. This may require a tooling set up that calls for a clam shell cut-off, a cone cut-off, or possibly the latest technology: vacuum cut-off. All three of these special tooling setups take up additional room in the form tube, causing the size of the auger and therefore, the output speed, to be reduced.
Dust removal is an area that also needs to be factored into the integration of the VFFS machine with the filling machine. Since the pouch is sealed on three sides, any dust from the fill will escape going up. If the application calls for dust collection, then dust collection is required to capture it, and it needs to be located within the forming tube – and that takes up valuable space.
Electrical specifications of each system are another area to consider. Often the end user will have an electrical specification that must be met. The filler supplier needs to know this upfront when quoting the project. There is also the possibility of the VFFS supplier and the filler supplier to share components. A good example of this would be to integrate control screens on a common HMI (human machine interface), thus giving the end user single-point control for the complete system. To do that effectively, it’s best to approach this objective early on.
One final point on machine integration: Discuss the factory acceptance test up front during the quoting process. Will there be a test at the filler company, the bagger company or both? What are the criteria for these tests? Will the VFFS company require technical assistance from the filler supplier for the test? What are the criteria for the start, installation and training at the customer’s plant? Technical assistance requirements should be defined and planned for in advance.
Bringing in all vendors together with the customer to discuss performance goals and share information early on in the design process will help streamline the integration between the FFS machine and filling machine. Vendors have expertise in their specific areas, and sharing information ensures all aspects of the integration will move along in a smooth and efficient manner.
Spee-Dee® Packaging Machinery Inc. is an industry leading supplier of dry product filling system solutions for the food, pharmaceutical and chemical industries. Since the 1940s, companies large and small from around the world have turned to Spee-Dee for greatly improved efficiency and productivity. For more information about its dry product auger fillers and volumetric cup fillers, visit Spee-Dee’s website at spee-dee.com.