The JKL Horizontal Travel Automatic Sampler with Bottom Dump Cutter is a primary sampling unit engineered to collect representative increments from free-falling material streams. It is typically installed in transfer chutes between conveyor belts in concentrator plants, ship loading systems, and material transfer stations.
Its design complies with the principles of Pierre Gy’s Theory of Sampling (TOS), ensuring proper sample delimitation and equiprobable extraction conditions, in accordance with international standards such as ISO 12743 and CNAM-007
1. Operating Principle
The equipment operates by transversely intercepting the entire free-falling stream using a rectangular cutter moving in a straight horizontal trajectory.
During each sampling cycle:
- The cutter starts from a rest position outside the material stream.
- It accelerates to reach constant velocity before intersecting the stream.
- It traverses the full cross-section of the stream at uniform speed.
- The increment is captured inside a collection box.
- The sample is discharged through a bottom-opening “Bottom Dump” mechanism.
- The cutter returns to its initial standby position.
This operating sequence guarantees:
- Complete cross-sectional interception of the stream
- Constant cutter velocity during stream intersection
- Full increment discharge without internal material retention
2. Mechanical Configuration
Structural Frame
- Fabricated from ASTM A36 structural carbon steel
- Reinforced design for high structural stiffness and dynamic stability
- Integrated lifting lugs for safe handling and installation
- Inspection and maintenance access ports
- Sealed lateral compartments for dust ingress protection
Drive System
- High-efficiency three-phase gearmotor
- Dual synchronized chain transmission system
- Integrated electromagnetic brake
- Wheels mounted on sealed antifriction bearings
- IP66-rated inductive proximity sensors for position monitoring
- Constant cutting velocity during stream interception (deviation < 5%)
Bottom Dump Cutter Assembly
- Rectangular cutter geometry (compliant with sampling standards)
- Symmetrical, self-cleaning stainless steel cutter blades
- Blade thickness and cutting edge angle engineered according to top particle size
- Collection box sized to prevent overflow during increment capture
- Mechanically actuated pivoting bottom gate for automatic discharge at end of stroke
- Vertical gravity discharge toward the secondary sampling stage
3. Integrated Chute Design
The sampler is installed between two chute sections:
- Upper Section: Impact absorber assembly and Internal deflectors for flow stabilization
- Lower Section: Independent discharge ducts for:
- Main plant flow
- Reject stream
- Spillage projections
- Primary sample discharge
Internal liners manufactured in 15 mm TIVAR 88 (UHMW-PE) in high-wear areas.
4. Critical Technical Design Conditions
- Straight-line transverse motion relative to the stream
- Constant cutter velocity < 0.45 m/s
- Complete stream interception
- Parallel and symmetrical cutter edges
- Cutter parked completely outside the stream
- Total increment discharge
- Internal chute angles ≥ 70° to prevent material build-up
- IP66-rated instrumentation protection
5. Technical Advantages of the JKL Bottom Dump System
- Elimination of delimitation error
- Elimination of extraction error
- Significant reduction of Fundamental Sampling Error (FSE)
- Complete discharge without internal accumulation
- High robustness for mineral concentrates and dry bulk materials
- Low maintenance requirements
- Simple integration with secondary samplers (DMR rotary divider or Vezin-type splitter)
- Ideal for metallurgical accounting and commercial shipment control
6. Typical Applications
- Concentrate ship loading operations
- Flotation feed control
- Conveyor-to-conveyor transfer points
- Metallurgical process control
- Mass balance verification
- Operations handling copper, lead, zinc, iron ore, and coal concentrates
7. Integration with JKL Sampling Systems
The unit may operate as:
- A two-stage primary sampling system
- A three-stage primary sampling system
Integrated with:
- JKL DMR rotary sample divider
- Vibratory feeders
- CMR rotary sample collector
- Power and control panel with HMI interface and industrial communication protocols
8. Contribution to Metallurgical Accounting
The Bottom Dump configuration ensures:
- Increment mass proportionality to throughput
- Statistical repeatability
- Reliability in commercial custody transfer
- Solid technical foundation for plant–mine–port reconciliation
Compared with non-linear systems (pendulum cutters, deflector-type samplers, or pivoting gate systems), the straight-path cutter strictly complies with international standards and prevents systematic sampling bias.
