How Does a Shrink Tunnel Machine Work?

A shrink tunnel or heat tunnel is a hot tunnel that is placed over or around a conveyor system. Items (such as packaging) have the film loosely applied; with heat, the film shrinks to fit well around the wrapped object.

A Shrink Tunnel Machine Manufacturers uses a conveyor and heat to maintain a constant temperature within the tunnel chamber. Shrink tunnels are often used for heat shrink packaging items, but can also be used to fix applications as well. Some heat shrink tunnels have two or more areas for heating and controlled cooling.

The three primary types of shrink tunnels are recursive, infrared, and steam tunnels. The deviation between each is how they produce heat. The tunnels are available with or without a conveyor system. Some are manufactured in a production line or integrated with machinery that also implements shrink film. Others are running by hand or by castors. Below is a description of how recirculating Shrink Tunnel Machine work.

A detail of Shrink Tunnel Machine’s primary working components:

1. Heater Bank

The heater bank shrinkage is the main component for heating the tunnel. The heater bank uses a standard heating element coil that heats up as soon as the heater is on. The heat produced is condensed around the heater coil. Recycling of air helps in achieving uniform heat distribution throughout the tunnel.

2. Blower Motors

Blower motors are those that recycle heat from the heater bank. Proper blower motor settings help ensure that the product is also heated throughout the tunnel. If the blower motors are blowing too much air on the product, the shrink film will burn.

3. Conveyor

The narrowing tunnel carries conveyor products to the exit from the tunnel entrance. The ability to adjust the conveyor speed enables users to control the timing of the product within the tunnel. Different products and materials require different heat exposure. The ability to adjust the tunnel from a slow crawl to several feet per minute helps to ensure consistent shrinkage with any shrinkage material.

4. Control Panel

A tunnel control panel must offer two primary controls. Temperature control and conveyor belt speed control. With these two controls a shrink tunnel can be fine tuned to offer the perfect heat for most applications.

There are many other working parts on a Shrink Tunnel Machine, but these four components help explain how a tunnel works. With proper settings, products should enter the shrink tunnel and exit.

Usage of Shrink Tunnel Machine:

• Shrink label

• A mixture of small items for sale and display (eg: bottled water)

• Tamper resistant or tamper-evident bands or seals

• Form large unit load for transport

• Primary inhibition on foods such as cheese, meats and fish

• Skin packs