For the past 35 years, Van der Graaf has been designing and manufacturing drum motors for an array of industries such as food processing, courier, postal parcel, airline baggage handling, pharmaceutical, automotive and other applications that utilize belt conveyors to move or process products.
Among the most demanding conveyor operating environments are aggregate and mining applications. Conveyor drives are required to perform under abrasive, dusty and high vibratory conditions, which can shorten the life of electric motors, gear reducers, bearings, sprockets, chains and “V” belts.
The harsh and demanding operating environments of the mining and aggregate industries, and high production demands, pose many challenges, among which is motor and gear failure.
Failure is mainly due to abrasive dust in coal mines, fine powdery dust in limestone quarries, abrasive steel particles in iron ore mines, as well as extreme belt tension. Although the drum motor has been used extensively to drive conveyor belts, it has not been used to a great extent in those industries, because the standard design did not address the operational conditions that exist in mines and quarries.
The engineers at Van der Graaf have expanded extensive research and development in the last five years to produce the all new GrizzlyDrive® design drum motor which addresses these industry specific operating challenges.
The GrizzlyDrive is a different kind of drum motor. It has been designed exclusively to reliably perform and operate in very harsh environments and demanding conditions. Currently GrizzlyDrives operate from the extreme cold (-50°F) temperatures of Labrador to the extreme hot (+40°F) temperatures of San Antonio.
All components of the drum motor are protected inside the drum. The robust mechanical seals are designed to prevent abrasive dust and water to penetrate the unit. The massive end-flanges on the GrizzlyDrive are engineered to deflect debris and rock overspill, and inhibits accumulation to occur between the drum motor and the conveyor frame.
The heavy-duty bearings have been designed for high static and dynamic rating to absorb heavy shock loads and high belt tension. The planetary and coaxial gear configuration design can absorb the high starting torque (240 percent) produced by the high torque design “C” electric motor that is able to start the conveyor under full load conditions.
The electric motor windings are manufactured with heavy-duty magnet wire and encapsulated with the vacuum pressure impregnation (VPI) process to withstand vibration and shock loads. The rubber lagging is hot bond vulcanized with or without ceramic tiles, is reinforced and installed in sections between welded bars in order to absorb the sheer loads produced by the belt.
The GrizzlyDrive drum motor has been designed exclusively for mining and aggregate applications, and is built like no other, according to the company.
Van der Graaf, www.vandergraaf.com