Banana Screen

The “Banana” screen is a more recent variation of the conventional inclined screen, becoming more common due to their high unit capacity and high efficiency.

The higher capacity is due to the steep initial screen angle (resulting in a fast moving bed, thus increasing overall screen capacity) and the high powered exciters usually installed on the screens. The rate of fines removal in this section of the screen is high.

The high efficiency is borne from the flatter bottom section, which provides an opportunity for good separation of the near-size material (particles of a dimension close to that of the screen aperture).

The upper practical limit for reliable high force banana screens is ~3.7m wide by ~8m long. Feeding such large screens normally requires a diverging vibrating feeder to ensure material is presented to the screen across the entire width, otherwise significant available screen area will be wasted.

Larger sized banana screens are normally supported on an Isolation Frame. This essentially consists of a heavy (usually by filling a steel structure with concrete) supporting frame, which is attached to the supporting structure through additional springs and shock absorbers. The Isolation Frame significantly reduces the transmission of the vibrating forces from the exciters through the supporting structure, meaning that concrete foundations are not required.