Flights, also commonly referred to as "material lifters" or "shovelling plates" are used in rotary dryers and rotary coolers to shower material through the process gas stream.[1] Fixed to the interior of the rotary drum, these fin-like structures scoop material up from the material bed at the bottom of the drum and shower it through the gas stream as the drum rotates. This showering creates a curtain of material spanning the width of the drum, helping to maximize the efficiency of heat transfer.
Depending on the needs of the material and the process, a variety of flight designs and placement patterns are used in order to create a maximum efficiency curtain while still retaining the integrity of the product.[2] [3]