Tunnel Kilns are computer-controlled, continuously operating car-bottom kilns. Pushers move the train of cars non-stop at a predetermined rate. This method is ideal for all ceramic industries requiring high volume production and/or a continuous production process. Computer technology allows kiln car movement through the kiln to be controlled for changes in firing curves and firing temperatures. This increases product recovery and minimizes production disruptions. Automatic controls can be programmed to make firing changes for differences in product size and color. Tunnel kilns vary in length, some being over 500 feet long.

A Shuttle Kiln is a car-bottom kiln with a door on one or both ends. Burners are positioned top and bottom on each side, creating a turbulent circular air flow. This type of kiln is generally a multi-car design and is used for processing whitewares, technical ceramics, and refractories in batches. Depending upon size and weight of ware, shuttle kilns may be equipped with car moving devices to transfer fired and unfired cars in and out of the kiln. Shuttle kilns can be either updraft or downdraft in design. A Shuttle Kiln derives its name from the fact that kiln cars can enter a shuttle kiln from either end of the kiln for processing, whereas a tunnel kiln has flow in only one direction.

Bell kilns are custom designed by Swindell Dressler International Company. SDIC offers different combustion systems for a variety of kiln shapes and sizes as required by the clients.

The Bell Kiln derives its name from its totally enclosed 5-sided kiln structure. This style of kiln consists of a shell that is lifted vertically by hydraulic cylinders and a car bottom on which the shell rests. Bell kilns are often chosen for use in the technical ceramics and refractory industries for batch-fired production. Major benefits include high uniformity of kiln temperature through the use of staggered top and bottom burners on all sides, and minimal square footage plant requirements compared to other types of kilns. Bell kilns use a downdraft exhaust system to significantly improve temperature uniformity by pulling the exhaust gases to the coldest part of the kiln (bottom center of the car). Bell kilns can easily be moved from one location to another if required.

High Temperature Tunnel Kilns require precise design and construction to deliver properly fired specialty products to the client. Special atmospheric controls are often necessary in these kilns. These controls, along with the need for esoteric refractory kiln walls, make these kilns a true custom collaboration between SDIC and the client.