Heron Grain Pre-Cleaner with oscillating body

Working Principle

• The working principle is based on the separation by size between grain and impurities.
• Dirty grain is discharged into the cleaner inlet and is distributed by a manually adjustable device to channel it in the right proportions to the different screens to ensure each screen obtains an equal amount of grain.
• The higher the capacity required in a cleaner, the more screen stages are involved.
• The sifter body separates the coarse trash first as overtails while the correct size kernel passes through the top screen onto the 2nd, fine screen.
• The correct kernel size then drifts over the fine screen and allows fine particles through the screen as throughs.
• The product is moved across the screen by means of a circular oscillating motion created by a weighted wheel fitted onto a shaft that provides the circular motion to the whole sifter.
• Each section’s overtails, throughs and just right sizes are collected in a tray and discharged at separate outlets or both overtails and throughs may be channeled to the same outlet.

Constructing Characteristics

• Constructed from formed mild steel sheets.
• Oscillating body hang from 8 steel cables.
• Screens are held together by adjusting ferrules and two front locks.
• The screen and body design promotes ease of operation and maintenance as well as the changing of screens.
• Screens are self cleaning by means of rubber balls located between the screen itself and a mesh below the sceen.

Available Models

ABC Hansen’s  Heron range of Grain Pre-cleaners are available in the following capacities (based on dry maize).

Aspiration:

It is recommended that all Heron pre-cleaners also be fitted with an aspiration system to remove all light particles screened with the kernel as well as dust that adheres to the raw material and is easier removed by aspiration than by screening. The aspiration unit consist of a grain spreader, the aspiration chamber, a powerful fan, a cyclone and a rotary valve. The fan sucks air through the cyclone which in turn is connected to the aspiration chamber where the grain sifts into after having been spread out by the spreader to allow dust and light particles to separate from the kernels. The dust is sucked into the cyclone where it sifts down in a circular motion to be let out via the rotary valve while the air remains behind and is discharged through the fan outlet.
This negative pressure system allows the fan not to be worn down with abrasive dust and other particles and for the cyclone to slow the air down to the extent where very little dust escapes the cyclone with air to maintain a low dust environment.