Polysius
- Collection
- Material falling from the apron pans is continuously collected
- Cleaning
- Accumulated material removed from underneath the feeder
- Recovery
- Collected material transported to the defined discharge point
One feeder, two functions
The polysius® RKF Apron Feeder is designed for reliable and controlled feeding of demanding raw materials in primary crushing and materials handling. Combined with the optional KK Chain Scraper Conveyor it becomes an integrated solution for feeding, cleaning, material recovery and — where process conditions allow — crusher bypass.
Integrated spillage management: The KK continuously removes material falling from the return side of the apron feeder.
Less manual cleaning: Continuous removal reduces material accumulation underneath the feeder and minimises manual housekeeping.
Crusher bypass: Where suitable fines can be separated from the main flow, the KK can route material directly to the downstream discharge conveyor.
Lower energy consumption: Unnecessary crushing is avoided, which reduces the energy required by the overall crushing system.
The KK operates independently of the apron feeder while forming one integrated mechanical solution — two machines mechanically, one operating concept in practice.
Keep the area under the feeder clean
The KK is installed directly underneath the apron feeder. It is designed to collect the material that falls from the return side of the apron pans during operation, and to carry it to a defined discharge point.
Main components
Nothing on this machine is there to be clever. Every component is chosen so that it can be reached, adjusted and replaced in a plant that runs on ROM material.
Heavy-duty steel-welded construction
Geared motor drive
Drive shaft with replaceable segments
Robust chain and scraper system
Return / tensioning station
Mechanical spindle tensioning
Bolted construction
Dedicated steel discharge chute
Self-cleaning material flow
The KK removes material from underneath the apron feeder continuously, while the plant keeps running. That is the difference between a housekeeping task that has to be scheduled and one that no longer exists.
Material accumulation: Spillage is carried away as it falls, instead of building up into a pile that has to be dealt with later.
Blockages underneath the feeder: The space below the feeder stays clear, so accumulated material cannot restrict the return side.
Manual cleaning activities: Less manual housekeeping in the area of the machine, and fewer people working underneath it.
Difficult access for maintenance: Maintenance starts at the machine rather than with clearing a path to it.
Uncontrolled material build-up: Material goes where the process intends it to go, at the rate it arrives.
Independent operation: The KK runs independently of the apron feeder, so cleaning does not depend on what the feeder is doing.
Less spillage. Less cleaning. Less downtime.
Don’t crush what doesn’t need to be crushed
The strongest process benefit of the integrated concept is the potential to route suitable fine spillage — the material that falls from the apron pans — around the primary crusher instead of through it.
Simple. Robust. Maintainable.
The KK uses a conventional geared motor drive combined with a robust mechanical chain system. There is very little on it that cannot be understood, adjusted or replaced by the people who run it.
Drive shaft: The drive shaft incorporates replaceable segments, so worn drive components can be exchanged without replacing the complete shaft assembly.
Tensioning station: Chain tension is adjusted mechanically at the return and tensioning station, using spindle-based adjustment.
Steel construction: The conveyor frame is a robust welded steel construction with bolted connections.
Discharge chute: A dedicated steel discharge chute provides a controlled transfer into the downstream material flow.
The main benefit is not the conveyor itself. It is the complete operating concept.
Two ways the same shift can go
Spillage under an apron feeder is not a question of whether it happens. It is a question of who deals with it, and when.
| Without integrated spillage management | With RKF + KK |
| Material accumulation | Continuous collection |
| Manual cleaning | Controlled transport |
| Higher maintenance effort | Cleaner machine area |
| Difficult access | Less manual intervention |
| Potential downtime | Potential crusher bypass |
| Optimised material flow |