There’s no denying the fact that the shrink sleeve is taking off. With the growing need for shrink tunnels, the industry has seen many exciting technological advancements in recent years. If you’ve stumbled upon this article, it’s very likely you yourself are in the process of choosing a shrink tunnel for your business.
But it’s extremely important that you review all the different types of shrink tunnels. You need to make sure the one you purchase matches your needs. If you buy the wrong shrink tunnel, you may contend with unwanted problems, like costly repairs, injuries, and wasted time. By reading this article, you’ll have a better understanding of what to look for as you shop.
What Is a Shrink Tunnel?
A shrink tunnel, which some also call a heat tunnel, is a metal tunnel situated above or around a conveyor. With a strong built-in heat element, shrink tunnels warm up shrink film so the film forms uniformly around an item as it passes through.
Steam Shrink Tunnels
Steam shrink tunnels leverage steam instead of using hot air for shaping plastic coatings onto products. Workers usually use them in projects involving tamper-evident packaging, like shrink sleeves.
Like all other options on this list, there are advantages and disadvantages to purchasing a steam shrink tunnel. For these machines, you don’t need to purchase an air compressor. However, they do need a source of water. The devices will be costly, as you must account for the water expenses.
Self-Contained Steam Shrink Tunnels
Self-contained steam shrink tunnels are a variation that differ from standard steam tunnels in that they use steam generators. These generators reside inside the machines. Self-contained steam shrink tunnels don’t need any additional attachments. Traditional steam tunnels, by contrast, require additional components to pipe steam into the machine. Since these machines are so different from other steam shrink tunnels, some states mandate special licenses and training to operate them.
When high-end graphics are the goal, steam shrink tunnels are the option you want to choose. They work especially well for projects requiring vibrant colors, stellar fonts, and consistency.
They create an extremely uniform heat transfer, which is superior to systems that use hot air. With a self-contained steam shrink tunnel, you’ll achieve superb precision registration and better shaping around the item. Through this, the sleeves become tighter, and they’ll also be more even. The graphics will look more professional on the sleeve. Companies that use self-contained steam shrink tunnels will benefit from improved shelf appeal. They’re an excellent option when packaging flammable products or products packaged under high pressure.
Convection Shrink Tunnels
The next machine on our list of the different kinds of shrink tunnels is the convection shrink tunnel. A convection shrink tunnel produces hot air, then blows it onto a plastic sleeve. The sleeve surrounds the product, and the heat shrinks evenly around the item.
“Baffle” is the name given to the module from which the warm air blows. The module moves the heat toward whichever direction allows for the best possible distribution of cold and hot air. Some typical applications for convection shrink tunnels include frozen pizza boxes and board games.
These tunnels do have their disadvantages, however. Hot air isn’t a great medium for transferring heat. When using hot-air systems, heat can overexpose and distort the film. This can often happen with glass containers or cold-filled plastic containers. You can mitigate the issue by rotating the container as it goes through the tunnel with a “spinning” conveyor.
Radiant Shrink Tunnels
Radiant shrink tunnels leverage radiation as their heat source. With sleeves that absorb infrared radiation, these tunnels are great for jobs that require a low shrink percentage. Workers typically use them in tamper-evident packaging projects, like sealing bands.
Since they deliver infrared heat that remains in the chamber, radiant shrink tunnels create an oven-like shrinking environment. However, because their shrink environment is so harsh, it may be hard to get the ideal shrink result. For instance, the side of a container entering the tunnel first may get shrunk before the other end comes in, causing an uneven appearance.
Which Shrink Tunnel Should You Choose?
If you’re trying to determine which shrink tunnel is ideal for your needs, you must first ask yourself a handful of questions. This is, after all, a big investment. You want to make sure you match the right machine to the right application. Some of the considerations you should ponder are laid out below.
How Heat-Sensitive Is My Product?
If you have a heat-sensitive product, the type of shrink tunnel you use should reflect that. Businesses with heat-sensitive products should use a convection shrink tunnel. Using these devices, you’ll have a greater amount of control over how the cold or hot air affects the product.
Do I Need Exceptionally Clean Graphics on My Product?
If you do need exceptionally clean graphics on your product, then you should choose a self-contained steam tunnel. Using these devices, you’ll see the superior results you want.
How Much Money Can I Spend?
As with any business decision, the final deciding factor is almost always cost. Convection tunnels are usually the cheaper option. Steam tunnels will be more expensive. Weight the pros and cons of a larger or smaller investment.
As you shop for a shrink tunnel, you should think about why you need the device, how much you’re willing to spend on it, and how you’ll keep your facility safe and prepared for its arrival. Shrink tunnels offer an exciting opportunity for businesses looking to improve their packaging. The technology in this industry is always moving forward, so there’s never a bad time to jump on the train. If you’re curious about the possibilities presented by wrap-around case packers, you should visit Robopac. We’re always ready and excited to speak to new customers. Give us a call if you have any questions or thoughts about shrink tunnels. As experts in the industry, nothing makes us more excited than a chance to introduce this technology to new people and businesses.