Exploring The Different Types Of Shrink Tunnels
If you are entering the market for a shrink tunnel, you will find yourself with a big variety of different types of machinery. Some machines work with steam. Others use hot air. Every kind of shrink tunnel is designed to work for specific applications.
Using the wrong shrink tunnel for the incorrect application can lead to various unwanted problems such as waste, downtime, costly repairs, and potentially, injury. When shopping for a shrink tunnel, you’re going to have many questions about the equipment.
At the end of the day, you just need to know which type of shrink tunnel is right for your products. Luckily for you, it is a fairly easy process to identify the best machine for your needs after you have done a little homework!
Industrial Packaging has been working with shrink tunnels for generations. During that time, we have become experts on the various makes and models of shrink tunnels, what makes them tick, how to keep them running smoothly and how to repair them with ease when they eventually break down.
With the information in this article, you will be able to choose the right machinery for your shrink tunnel applications and product packaging needs.
What Exactly Is A Shrink Tunnel?
A shrink tunnel (also commonly known as a heat tunnel) is a metallic tunnel that sits above or is built around a conveyor. The tunnel has a heating element that heats the products as they move through the machine. Your products are conveyed through the tunnel and are cloaked with loosely fitting shrink film. When your products move past the heating elements, the film shrinks uniformly around the items as they are exposed to the heat.
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Different Kinds Of Shrink Tunnels
Steam Shrink Tunnels
Steam shrink tunnels use steam rather than hot air to produce the heat required for shrinking plastic substrates on products. Steam tunnels are most commonly used for tamper-evident packaging applications, such as shrink sleeves.
Bottles with shrink sleeves.
While steam shrink tunnels are not pneumatic machines, and therefore do not require an industrial level air compressor, they do require a water supply. As such, when considering purchasing a steam shrink tunnel, you need to understand that these machines will be more expensive because they require the use of a utility.
Self-Contained Steam Shrink Tunnels
There is a variation of the steam shrink tunnel known as a self-contained steam shrink tunnel. The self-contained tunnel differs from the standard steam tunnel in that it has an internal steam generator which generates the steam without additional attachments. In contrast, the traditional steam tunnel needs steam piped into the machine which requires additional components.
You may be required to have a steam engineer on the payroll to operate your steam tunnel as some states require special training and licenses to operate these types of shrink tunnels.
Steam shrink tunnels are specially made to run on product lines in which quality and high-end graphics are favored. If your products require spot on registration, brilliant colors, perfect fonts and long term consistency, steam shrink tunnels are for you.
Steam shrink tunnels allow for highly uniform heat transfers which are superior when compared to hot air systems. Steam-based machinery provides high precision registration capabilities and better shape forming. This means that the sleeves will fit tighter and more evenly and the graphics and aesthetics will look better on the sleeves resulting in better shelf appeal.
Steam tunnels are a good choice when packaging containers which are packed under high pressure or for packaging products that are flammable.
Convective Shrink Tunnels
With convection shrink tunnels (also known as hot air shrink tunnels) the machines produce hot air which is blown onto a plastic sleeve that surrounds the item being packaged. The heat shrinks the sleeve around the product evenly.
The hot air is blown from a module known as a "baffle." These modules direct the heat in any required direction which allows for superior distribution of heated or cooled air. The packaging of board games and frozen pizza boxes are common applications for this type of machine.
Radiant Shrink Tunnels
Radiant shrink tunnels use radiation as the tunnel's heat source. The sleeves in the machine absorb this infrared radiation. Radiant shrink tunnels are perfect for packaging applications that require lower shrink percentages. Radiant tunnels are commonly used for shrinking seal bands and other types of tamper-evident packaging materials.
Which Type Of Shrink Tunnel Is Right For You?
To appropriately answer the question above, you will need to answer a few questions yourself. Here are a few items of consideration to ponder when trying to figure out which type of shrink tunnel is a good fit for your products and packaging line.
Are my products heat-sensitive? If you answered yes, you would want to consider getting a convection shrink tunnel. It will give you greater control over the distribution of hot or cool air.
Do I require high-end graphics and branding capabilities for my products? If you answered yes, you would want to purchase a self-contained steam tunnel as they produce superior results when graphics and registration must be of the highest quality.
What is my budget? Depending on your financial limitations, you may want to stick with a convection tunnel as steam tunnels require additional utilities and, in some cases, highly trained specialized operators.
Answering these few simple questions will help you to make a better choice when it comes to purchasing a shrink tunnel for your packaging line.
If you are still unsure about which type of shrink tunnel is right for you or if you would prefer to have someone else do all this comparison work, consider reaching out to one of our packaging experts.
They will be able to send you an in-depth comparison of several different makes and models with a recommendation on the brad, make, and model that is the correct machine for your specific applications.
Your packaging expert will be able to help you choose the right shrink tunnel machinery for your packaging line, as well as the best vendor for your needs. We can help you in this process even if we do not end up being the vendor that you ultimately choose to do business with.
About Nathan Dube
As the Digital Marketing Specialist at Industrial Packaging, I am honored to create content for such a phenomenal company and work with one of the greatest teams in the Packaging Industry. Whether creating a video, writing blog posts or generating other pieces of content and multimedia, I am always excited to help educate and inspire our prospects and clients to reach their highest potential in regards to their packaging processes and needs.