When to Use a Tunnel Kiln

A tunnel kiln is a continuous moving ware kiln, in which the products to be heated are passed through in cars through a long tunnel. Heating of the products takes place at the central area of the tunnel. Tunnel kilns provide the best levels of fuel efficiency and cost-effective operation in instances where mass production is required.

How Does a Tunnel Kiln Work?

In a tunnel kiln, cars are loaded and pushed into the kiln, these cars are then moved inside intermittently at fixed time intervals. Cold air enters the kiln from the car exit and is heated whilst cooling the loads. Hot air and gases are then extracted from the tunnel kiln at multiple points throughout the length of the tunnel and are released through a chimney.

Tunnel Kilns

Uses of Tunnel Kilns

A tunnel kiln should be used in applications which require a constant, high-volume production line. A tunnel kiln has a variable cycle time, meaning they are ideal for integration with a continuous or automated production line. Tunnel kilns are low maintenance and do not need as much manual labor to operate, meaning employees are free to work on other things. Usually only annual or biannual maintenance is required, meaning they are cost-effective. Tunnel kilns have a large footprint to accommodate loading and unloading tracks, which is why the customizable options from Deltech are so beneficial.

Tunnel kilns are often used for applications in which temperature uniformity is important and when high levels of control are needed. A tunnel kiln has a 50% lower fuel consumption than a shuttle kiln and is extremely energy efficient.

Tunnel kilns are frequently used in applications such as:

• Clay brick firing
• Sanitaryware
• Porcelain insulators
• Technical ceramics
• Vitrified clay pipe
• Tableware

Tunnel Kilns from Deltech

Significant changes in product outcomes can arise from moving from electric to gas fired furnaces. A custom tunnel kiln from Deltech provides a means of scaling up while mimicking conditions present in resistance heated batch furnaces.

With larger process parameters, a tunnel kiln may be optimal rather than a top hat, bottom loader or front load furnace as they still preserve the rapid heating and cooling temperature uniformity characteristic of other Deltech furnaces.

A customized tunnel kiln from Detlech can sustain operating temperatures of up to 1800°C, has the option of being fiber board or ceramic lined and can be configured as either single or multizone, including preheat and cool down sections.

They offer the option to control atmosphere capability, add additional length as product demand grows and control systems that are custom made. If you are looking to learn more about a customized tunnel kiln from Deltech, contact us today for more information.