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