Continuous Vertical Lifting Where Safety Comes First

Direct Answer
A vertical sidewall conveyor for coal mining is a continuous lifting powerhouse designed to move raw coal vertically — up to 90° — without spillage, rollback, or uncontrolled discharge.

The Real Pain Underground
Coal mines are not quarries. Underground shafts and drifts are defined by:
– Extremely limited space
– High dust concentration
– Moisture, mud, and abrasive fines
– Strict safety and explosion-prevention requirements

If you need to lift coal 30–50 meters vertically, a traditional inclined conveyor would require hundreds of meters of horizontal space — often impossible underground.
Skip hoists solve the height problem, but introduce others: intermittent flow, complex mechanical systems, and higher operational risk.

This is where a steep angle coal conveyor becomes a serious engineering alternative.

Trust Signal
Properly designed DJ sidewall conveyors for mining applications are built with flame-retardant, anti-static (FRAS) belts, heavy-duty cleats, and rigid belt cores — all essential for underground coal operations.

Solving the Space vs. Capacity Dilemma in Mines with Vertical Sidewall Conveyor

Typical Scenario
– Lifting raw coal from underground workings to surface
– Feeding coal vertically into a Coal Preparation Plant (CPP)
– Retrofitting existing shafts or raises without additional excavation

In these cases, excavation cost is often higher than equipment cost.

By using a vertical coal lift, a sidewall conveyor:
– Eliminates the need for long inclined drifts
– Reduces tunneling and civil work
– Delivers continuous flow, stabilizing downstream screens and crushers

Material Reality
Raw coal is rarely uniform. It usually contains:
– Mixed lump sizes (fines + 50–100 mm lumps)
– Moisture from water sprays or groundwater
– Sharp edges that punish weak components

This makes durability, not just inclination angle, the key selection factor.

 

Engineered for the Pit: Component Durability Matters

Vertical conveying underground leaves no margin for design shortcuts.

Base Belt Cross-Rigidity (Critical Factor)

In a vertical run, the belt must resist bending sideways under load.

A cross-rigid base belt ensures:
– The belt remains flat on the return side
– Sidewalls do not collapse inward
– The belt does not jam in confined shafts

Without sufficient cross-rigidity, even a small misalignment can cause shutdowns that are difficult to fix underground.

Cleat Design for Coal Impact

Coal lumps strike cleats with far more impact than sand or aggregates.

For mining use:
– Reinforced TC or TCS-type cleats are preferred
– Cleats must be hot-vulcanized or mechanically reinforced
– Thin, flexible cleats used in light-duty applications are not acceptable

This is where many “general-purpose” sidewall belts fail in coal mines.

 

Sidewall Conveyor vs. Bucket Elevator: A Practical Comparison

Bucket Elevator (Traditional Option)

– Chain-driven or belt-driven buckets
– High dust generation at transfer points
– Vulnerable to bucket jamming with large coal lumps
– Chain breakage risk in abrasive environments

Sidewall Conveyor (DJ Type)

– Continuous conveying instead of batch lifting
– Handles larger lump sizes gently (100 mm+)
– Lower coal degradation
– Fewer high-speed moving parts

Trade-off Disclosure
Sidewall conveyors demand better belt quality and more attention to cleaning. Carryback management is harder than with flat belts, especially in wet coal conditions.

 

Critical Safety Check: Belt Rigidity & Compliance with sidewall conveyor for coal mining

In underground coal mining, safety is not negotiable.

1. Verify Base Belt Cross-Rigidity (XE Value)

Ask for the XE (cross-rigidity) test report:
– Example: XE-400 or higher for vertical coal lifting
– The belt should not sag or twist on the return side

This is a measurable, verifiable parameter — not marketing language.

2. Confirm Flame-Retardant & Anti-Static Compliance

For underground use, the belt compound must meet:
– Flame Retardant requirements
– Anti-Static limits to prevent spark accumulation
– ISO / AS mining safety standards (FRAS)

Never assume compliance — always request certification.

 

Trust & Safety: High-Risk Area, No Compromise

Coal mines are classified as high explosion-risk environments.

Mandatory requirements include:
– Explosion-proof (Ex-d) motors and gearboxes
– Flame-retardant conveyor belts
– Reliable backstop devices to prevent reverse rotation in vertical shafts

Operational Limitation (Honest Disclosure)
For raw coal with high moisture content (>15%), carryback becomes a major challenge.
Specialized beaters or air-knife cleaners must be installed at the discharge head to prevent pocket clogging and material buildup.

Ignoring this leads to downtime — not theoretical risk, but real operational pain.

 

Conclusion: Continuous Vertical Lifting Built for Coal Mines

For coal mines operating in confined underground spaces, a DJ vertical sidewall conveyor offers a safer and more continuous alternative to skip hoists and bucket elevators.

It is not a universal solution — but when space is limited and capacity matters, it delivers:
– Smaller footprint
– Continuous flow
– Lower mechanical shock
– Better integration with CPP systems

Call to Action
– Get a quote for FRAS heavy-duty sidewall belts
– Consult on vertical shaft and conveyor layout for coal mining applications