Tips, Tricks, and Best Practices
Shrink sleeving is one of the most versatile labeling solutions for modern packaging, providing 360-degree coverage and a professional finish. At Eastgate Group, we often get asked: “Should I use a steam tunnel or a heat tunnel for my shrink sleeve application?” Understanding the differences can help you choose the best method for your product line.
What Are Shrink Tunnels?
A shrink tunnel is a key piece of equipment used to apply shrink sleeves to containers. It works by applying heat to the label, causing it to shrink and conform tightly to the shape of the container. The two primary types of shrink tunnels are steam tunnels and heat tunnels. Each has unique advantages and considerations.
1. Steam Tunnels
How Steam Tunnels Work
Steam tunnels use high-temperature steam to shrink labels. The steam heats the polymer in the shrink sleeve, causing it to conform to the container’s shape.
Advantages
Uniform Shrinking: Steam penetrates evenly, minimizing wrinkles and bubbles.
Energy Efficient for Short Runs: Uses less energy than some heat tunnels for smaller batches.
Gentle on Packaging: Ideal for sensitive containers that may warp under extreme dry heat.
Disadvantages
More Expensive: Steam tunnels are typically expensive than heat tunnels and require a boiler
Moisture Considerations: Not suitable for moisture-sensitive products.
Maintenance Needs: Requires careful cleaning to avoid mineral buildup from steam.
Ideal Applications
Bottles or containers with delicate shapes
Products where precision and appearance are top priorities
Small to medium production runs
2. Heat Tunnels
How Heat Tunnels Work
Heat tunnels use hot air to shrink sleeves. They blow heated air over the container to evenly shrink the label around its shape.
Advantages
Lower Cost: Ideal for clear shrink bands or non-decorative shrink sleeves
Flexible for Various Products: Works with many container materials, including plastics and glass.
No Moisture: Safe for products that should not contact steam.
Disadvantages
Risk of Wrinkling or Overheating: Labels can shrink unevenly if settings are incorrect.
Higher Energy Use: May consume more energy compared to steam for certain applications.
Temperature Sensitivity: Some containers can deform under high heat.
Ideal Applications
Clear shrink bands that don’t require aesthetically pleasing results
Containers that are heat-resistant
Products sensitive to moisture exposure
