Rulmeca Corporation has supplied thousands of Motorized Pulleys to drive conveyors in a “dual drive” configuration, such as the “nested” arrangement pictured here. The photo shows two model 800H Motorized Pulleys (each at 120 HP) on the return belt strand of a bucket wheel reclaimer discharge conveyor. This is one of numerous examples of a dual drive arrangement offering benefits to the conveyor operator, including reduced slack side tension and extended belt life. This blog post presents several examples of “dual drives” on mobile equipment and in fixed plants.
We supply Motorized Pulley belt conveyor drives, serving equipment manufacturers directly and end users through a network of independent distributors & local service providers throughout the United States and Latin America.
Recirculating Plant in Operating Mode (Wisconsin) – Mobile plant uses two 15.75” diameter 15 HP motorized pulleys to drive 850 TPH 384 fpm 36” wide screen feed belt. Actual full load screen feed power requirement is 23.5 HP. Dual drive (head and tail) arrangement was necessary because conveyor drive width was severely restricted in order for plant to adhere to US highway clearance requirements. Since one 25 HP Motorized Pulley was too wide to fit into head position, a dual “head and tail” configuration was selected. Photo taken while plant was operating after nine years of service in gravel pits.
Recirculating Plant in Transport Mode (New York) – End view of plant described above upon arrival at New York granite quarry. Note that 36” wide screen feed belt conveyor pins to structure adjacent to screen for transport mode. Road weight is 170,000 lbs. Maximum allowable highway plant clearance width of 12’ – 0” limited pulley face width to 40 inches. A single head drive consisting of a 25 HP model 500H Motorized Pulley would have been too wide. That is why two model 400M at 15 HP/each were used. Note that screen feed conveyor vertical pivot feature also simplifies gyratory crusher manganese replacement.
“Dual Drive”Head Pulley – Close-up of 15.75” diameter 15 HP screen feed head pulley described above. Pulley face width is 39.37” and motor is powered by 460V/3ph/60Hz power supply generated by separate portable diesel-powered motor-generator set. Motorized Pulley is mounted below conveyor structure due to close proximity of vibrating screen and maximum allowable highway plant clearance height of 13’ – 6”. Photo taken during plant start-up.
“Dual Drive” Tail Pulley – Close-up of 15.75” diameter 15 HP screen feed tail pulley for 700 tph recirculating plant similar to the one described above. Photo taken in 2003 after three years of service. Motorized pulley is mounted on top of pedestal-type jacking screw belt take-up assembly. Note that electrical connection requires a “festoon loop” in flexible conduit to connect movable drive pulley to conveyor structure.