Application and Difference of Shaft and Shaftless Trommel Screen

There are 2 kinds structure of trommel screen. One is trommel screen with shaft, the other is shaftless trommel screen. Generally both of them can be applied in some common bulk material, however, for material with special property, we must pay more attention to select a more suitable model according to the application working condition.
Trommel screen with shaft: 
The drum is installed aslope on the main frame. The motor and gearbox connect the drum through a coupling and rotates around an axis. After the material fed into the drum, the material can move forward and rotate due to the inclination and rotation of drum. The qualified material will be discharged from the bottom hopper, and the unqualified material will be discharged from the end outlet. As the material rotates in the drum, which make the blocked material bounced out of the aperture to prevent the mesh blocking.
Trommel screen with shaft is generally used for screening granular material with large density, such as: sand, coal, limestone, fertilizer, compost and mineral, etc.

Shaftless trommel screen: 
The shaftless trommel screen is installed horizontally. The drum is rotated driven by motor wheel gear or motor chain. Generally the rotate speed is very slow and the drum length can be designed longer, which can increase the screening efficiency. In the drum internal wall, there is a delivery plate ( sometimes screw type) to make the material move forward. The material which is larger than mesh size will be discharged at the end outlet, and the material which is smaller than mesh size will be discharged at the bottom discharge hopper. If the material is household garbage, we can also add a cutting tool, which can rive some plactis bags, etc. 
Shaftless tromme screen is generally used for screeninig material with small density, such as: waste, wooden chips, activated carbon, fertilizer, construction material, chemical material, etc.