What Is a Shrink Tunnel?
A shrink tunnel is a device used for shrink wrapping, a process that involves heat-treating a clear film to snugly fit around a product.
Uses of Shrink Tunnels
Shrink tunnels are employed in various industries, including food packaging for beverages, seasonings, canned goods, and cup noodles, as well as packaging for books, CDs, and pharmaceutical products. These machines facilitate flow-oriented shrink-wrapping processes.
Principle of Shrink Tunnels
A shrink tunnel typically comprises a device for applying and welding shrink film and a tunnel for heat treatment. Steam-type tunnels may include a boiler. Shrink film, supplied in rolls, is cut according to a product’s packaging needs, guided by a black register mark printed on the film.
Types of Shrink Tunnels
Shrink tunnels vary by heating method and include specialized models for large items, such as pallets.
1. Hot-Air Type
Uses hot air to shrink the film, suitable for small spaces but may result in uneven finishes.
2. Steam Type
Utilizes steam for even heating, requiring a boiler and larger installation space. Offers a high-quality finish but necessitates a steam removal process.
3. Hot Whirlwind Type (Tornado Type)
A recent innovation, this combines hot air with an air current to evenly distribute heat, achieving finishes similar to steam types.
Other Information on Shrink Tunnels
Purposes and Advantages
Shrinkwrapping serves various purposes:
- Protection of Goods: Prevents the entry of foreign matter, insects, and dust, enhancing product safety during transport.
- Improved Identification: Allows for larger product information display compared to traditional labels, aiding in product differentiation.
- Support for Multiple Product Variety Production: Facilitates the use of the same packaging for different products, reducing material waste and costs.
- Reduction of Packaging Costs: Enables cost-effective bundling of products and eliminates the need for additional packaging materials.
- Improved Transportability: Enhances product stability and damage resistance during shipping, particularly for mail-order items.
- Set Sales: Allows for the bundling of diverse products for sale as a set, applicable to a wide range of items.