The Duravant family of operating companies serve the food processing, packaging and material handling segments.
How to Choose the Right Shrink Wrap Seal Type
Other than basic speed and size requests, most of the questions I am asked during initial project discovery is “what type of package do I need?” While the traditional side seal is functional for a wide range of products, when there is a need for retail style packaging, other seal types can be useful for creating the most appealing package possible.
Traditional Side Seal
Is the traditional side seal right for me? This seal is created by forming a tube of film around a product, sealing the tube of film on its side, and removing the excess trim to a film accumulation winder. The advantage of the traditional side seal is the ability to adjust the film cutoff for similar sized products without changing the film. This means that cutting off more or less film becomes a function of a minor machine adjustment. If you have a product that is greater in width than it is in height, the traditional side seal is most likely the correct seal for you.
Traditional Top Seal
What makes the traditional top seal different from the traditional side seal? Basically...nothing. Every advantage found by utilizing the traditional side seal can be found in the top seal as well. The main difference is the sealing apparatus is mounted above the product versus to the side of the product. This creates a seal over the top of the product removing any seal lines on the side. The top seal works great if you have product with greater height than width or if you prefer the seal line on the top of the product versus the side.
Bottom Overlap (Lap) Seal
The bottom overlap seal, or lap seal, is created by forming film around a fixed forming structure that creates an envelope of film around the product. The film is overlapped underneath the product and sealed with static or with some type of energy transfer, e.g., heat. There are a few advantages for this type of seal versus the traditional side seal. The bottom lap seal uses less film than a traditional side seal as there is no requirement for excess to be cut and removed during the sealing process. With no waste, the lap seal machinery typically has less parts and less adjustment required than a traditional side seal machine. Because changeover is a factor, the bottom lap seal is great for a single dedicated product and if the top or side seal are not preferred aesthetically.
Zero Edge Seal
How do you feel about saving money on film cost? What about removing the need to throw away any excess film waste? With a recent breakthrough in sealing technology, we have entered a new era of shrink wrappers. nVenia has combined the advantages of the bottom lap seal and the traditional seals with the Zero Edge. The Zero Edge seal completely eliminates waste on shrink wrapping machinery, while allowing for easy changeover and adjustment. Perfect for dedicated products and available in both top and side seal (no trim) versions, this seal can lead to maximum uptime and reliability versus the traditional sealing technologies.
Now that you’re armed with all of the knowledge of how to choose a seal for your shrink wrappers, you are ready to choose your ideal shrink wrapper. Whether it’s a Zero Edge seal, a top seal or any other seal, you can feel confident that you’re making the correct choice for your application.
By Sam Sadler – Product Manager