MagnaDrive said the Cumberland mine transports raw coal from a storage silo into a preparation plant along a 650-foot long slope belt conveyor, which operates almost continuously and is critical to plant operation.
“The conveyor was previously driven by a 400 HP motor with a fluid coupling but operators wanted to increase capacity by speeding up the belt drive. They also wanted an alternative to the high maintenance costs and downtime associated with fluid couplings,” MagnaDrive said.
Cumberland replaced the original motor and fluid coupling with a 600 HP motor and MagnaDrive Coupling.
“They concluded that the MagnaDrive Coupling would be less expensive up front, simpler to install and align, plus offer significant other benefits including soft start, overload protection, no vibration transfer and no hot oil spills,” MagnaDrive said.
The company quoted David Rife, Cumberland maintenance supervisor as saying: "The MagnaDrive Coupling is definitely a winner. No vibration is transferred. Soft start and stop protects the driven units and lets the motor come up to full speed before engaging the driven equipment, helping get the conveyor started in overload conditions."
The company said its power transmission technology utilizes powerful rare-earth permanent magnets to transmit torque across an air gap with no physical connection between the motor and driven equipment.
MagnaDrive's Adjustable Speed Drive is for variable speed applications up to 1500 HP, such as pumps, fans and blowers, where precise process control, energy savings, reduced vibration and low maintenance is desired.
The MagnaDrive Coupling is designed for constant speed applications up to 1000 HP, such as conveyors, where low cost, easy installation, efficient torque transfer without vibration, overload torque protection, cushioned start and stop, misalignment tolerance and low maintenance are desired.
"A unique benefit of the MagnaDrive Coupling is its performance in torque overload situations such as material jams or excess weight. The Coupling automatically disengages, shutting down the system and preventing damage or destruction of the motor and driven equipment. When the jam is cleared, the Coupling automatically resets to resume operation."
