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BELT CONVEYORS

MARCH 17, 2015

Gordon Cross, P.Eng, PMP

STARTING METHODS

Belt Conveyors

Componets of a Conveyor

END PULLEY END PULLEY

SNUB PULLEY BEND PULLEY

RETURN IDLERS CARRYING IDLERS

GRAVITY TAKE-UP

TRIPPER

SKIRT BOARD

IMPACT IDLERS

DISCHARGE HOOD

SCRAPER

BELT CLEANER

Conventional Starting

Modern Starting

Pro’s and Con’s

Wound Rotor Motors

Pros: • High Starting Torque • Can handle long acceleration times (long conveyors) • Some control over start-up speed • Lower starting current • Suitable for the harshest of environments

Cons: • Wear of mechanical parts • No Speed adjustments • Higher Motor Cost • Lower efficiency • No regeneration

Pro’s and Con’s

Fluid Coupling

Pros: • Economical • Some control over starting ramp • Low initial cost

Cons: • Limited Motor size (~1000kW) • No regeneration

Pro’s and Con’s

Variable Frequency Drives

Pros: • Speed Control possible • Minimal dynamic effects on conveyor • Regeneration possible

Cons: • Limited Starting Torque • Complexity • Higher initial cost

Pro’s and Con’s

Gearless Drives

Pros: • Speed Control possible • Fewer mechanical parts • Regeneration possible • More cost effective (at higher capacities)

Cons: • More difficult to install • Currently only available for larger

applications • Have not been proven over time

Gearless Drives

Gearless w/o Motor bearings

Gearless with Motor bearings

Gearless with coupling

Outlook

Wound Rotor Motors

Fluid Couplings

Variable Frequency Drives

Gearless Drives

If things do go wrong

Conveyor Overspeed

If things do go wrong

Resistor Overload

If things do go wrong

Maintenance Issue

Questions?

Gordon Cross, P. Eng, PMP