ROTARY DRUM SIEVE

Counter-Flow Cleaning Technology

General Definition

An industrial pre-cleaning equipment located at the entry point of grain cleaning facilities, designed to separate coarse and large impurities (such as rope, wood, stones, and cobs) from high-tonnage raw materials. Its body features a fully enclosed and dust-tight structure, providing maximum efficiency to plants with its vibration-free operating principle and low energy consumption.

Operating Principle

• Counter-Flow Cleaning: When the product enters the screen drum, the internal helical flights or guide tips convey the product toward the outlet.

• Precise Separation: Grains with appropriate specific gravity and size drop through the screen perforations into the lower hopper via gravity and centrifugal effect.

• Coarse Waste Discharge: Ropes, pieces of wood, and stones are directed to the coarse waste outlet at the end of the drum and quickly removed from the system.

• Zero-Clogging Technology: External nylon brushes or free-rotating rubber rollers contacting the outer surface of the drum are used to clear debris and ropes stuck in the screen perforations.

Key Advantages

• Modular & Segmented Drum Structure: The screen drum consists of segmented perforated sheets. In case of wear, instead of replacing the entire drum, only the relevant segment can be quickly renewed.

• Extremely Low Energy Consumption: Even at high tonnages, the drum is rotated with very low motor powers, minimizing operational expenses.

• Vibration-Free (Dynamic Load-Free) Operation: Unlike vibrating screens, because it operates with a rotary motion, it does not transfer loads or vibrations to the building frame and steel construction. It requires no additional insulation or heavy concrete bases.

• Rapid Product Changeover: When transitioning to different grain types (wheat, corn, sunflower, etc.), screen segments can be replaced in a short time thanks to wide side covers on the body.

• Dust-Free and Safe Operation: The body is enclosed and suitable for operation under negative pressure. It prevents dust dispersion into the plant.

Critical Role in the Plant (Process Safety)

Positioned at the very beginning of the cleaning house, it acts as a protective shield for all sensitive equipment following it:

• Sensitive Machinery Protection: Protects aspirators, separators, destoners, trieurs, and especially roller mills from jamming, screen tearing, and roll damage caused by large foreign objects.

• Continuity: Minimizes plant downtimes and unexpected breakdown costs.

Maintenance and Operation Recommendations

• Brush and Roller Adjustment: The contact pressure of external cleaning brushes against the drum sheet should be checked periodically. Insufficient pressure leads to screen clogging, while excessive pressure causes premature brush wear.

• Bearings and Housing: The dust seal gaskets of the bearings carrying the drum must be regularly checked, and the lubrication schedule must be followed.

• Screen Segment Wear Inspection: When working with abrasive products, it should be regularly measured whether the screen perforation diameters have expanded.