MechChem Africa January 2019

Hytec recently commissioned the R10-million hydraulic systems it developed for the new bulk handling equipment installed at Assmang’s Black Rock Mine Operations in the Northern Cape. Hydraulic systems at Black Rock commissioned

B lack RockMineOperations is being operated by Assmang Proprietary Limited, which is jointly owned by African Rainbow Minerals Limited and Assore Limited. The mine’s bulk materi- als handling system includes two stackers, a bucket wheel reclaimer and a rapid load- out station – each automated using Hytec’s proportionally controlled hydraulic systems assembled fromBoschRexroth technologies. “The proportional control achieved by the system delivers precise remote flexibility in adjusting, varying and optimising the load handling characteristics of the machinery to accommodate any changes in the nature of the material,” explains Hytec’s system sales manager, Klaus Marggraff. The two stackers, manufactured by ELB Engineering Services, were equipped with 7.5kWhydraulic systems thatwill control the stacking of manganese ore in the stockyard for the various grades of material. The Sandvik (nowFLSmidth) bucketwheel reclaimerwassuppliedwitha45kWhydraulic system and includes dual luffing cylinders. At the load-out station, Hytec’s hydraulic systems extend from the control of the exit gates of the loading bin, across the weigh flask that divides the load into batches that are then transferred into the wagons below. Up to 600 ℓ /min of hydraulic flow is required at specific stages of the load-out station, which also needs to deliver precise

The automated load-out station receives ore from the bucket wheel reclaimer, which it weighs and divides into batches that are then deposited into rail wagons below. Inset: The hydraulics ensure that the loads are evenly and accurately distributed, maintaining the integrity of the axle load to strict tolerances.

distributioncontrolwithineachwagon,within strict tolerances. “The load-out station is equipped with an emergency closure system which, when activated in the event of a power failure or an emergency stop, will automati- cally close each gate and park the machine,” Marggraff explains. “Each component used on the system: valves; cylinders; the filtration systems filtering the oil down to six microns; and the controllers, are from the Bosch Rexroth range of drive and control products,” Marggraff continues. All of the hydraulic equipment, which was supplied by Hytec as a turnkey solution including design, engineering, installation and commissioning, is contained within pres- surised enclosures equippedwith specialised air filtration systems. “While physically inte- grating these enclosureswithin limited space on these machines was challenging, it means the components are shielded from the dusty miningenvironment.Thisfurtherenhancesan alreadyhighlymaintenance-friendlysolution,” Marggraff says. For Hytec, this is the latest in a large port- folio of hydraulic solutions supplied for bulk material handlingequipment across Southern Africa, and the company has a long history of collaboration with miners in the manganese industry. Turnkey hydraulic solutions for materials handling

Below: One of two stackers responsible for loading manganese ore onto the stockyard. These are equipped with 7.5 kW hydraulic systems from Hytec. Right: 45 kW hydraulic systems allow the bucket wheel reclaimer to achieve required throughputs.

14 ¦ MechChem Africa • January 2019