Belt Conveyors, Stackers and Reclaimers
Iron ores, coal, precious minerals and similar materials extracted from mines, need to be transported to different points of use - such as processing plants or stocking piling - for sea transportation to other end users. Conveyor belts, stackers and reclaimers are the main machinery used for this purpose.
As regards the transported material rate (which in some cases can be higher than 15,000 tons per hours), the expected productivity of such machinery is extremely high. Consequently, such machinery also requires powerful and reliable drives with a power rating of up to 10,000 kW. Flexible Couplings are generally installed onto high speed shaft of the drive train, in order to compensate misalignments bet - ween the motor and the gearbox. Furthermore they are installed onto low speed shaft, between the gearbox and the pulley, when the pulley unit is installed onto a separate base unit from the gearbox itself (typical configuration of high powered conveyors). The flexible coupling should also compensate misalignments generated by thermal expansions phenomena, as well as reduce shock load transmissions.
Inclined conveyors also require safety equipment in order to maintain the stability of the transported material in emergency conditions. Such situations include failure of the drive train and the resultant rolling back of the belt with a potentially dangerous depositing of the goods at the tail end. Another example would be overspeeding of the belt for regenerative conveyors. For these purposes either BACKSTOPS or brakes systems must be properly selected to withstand the most critical working conditions to which the conveyor will be subjected.Motor starting torque, run back torque, conveyor stopping time, conveyor speed, are just a few mandatory variables to be considered regarding couplings, BACKSTOPS and brakes system design.