Voith Turbo has developed a new coupling, the TurboBelt 780 TPXL, for the drives of long open pit mine belt conveyors. It has been specially designed for induction motors operating at speeds of 900 to 1,200 rpm. The fluid coupling transmits twice the power previous couplings of the same size could achieve. The controlled start-up with precisely-dosed introduction of torque is especially easy on the belt, but also on the entire driveline. Start-up times of up to several minutes can be individually set in the control system.
At the heart of the new development is the profile of the blade wheels in the coupling. Voith’s fluid engineers have optimised this profile using modern numerical techniques of flow simulation (computational fluid dynamics or CFD). The blade wheels transmit double the power with the same diameter. The TurboBelt transfers 1,100 kW at 900 rpm, 1,500 kW at 1,000 rpm and 1,900 kW at 1,200 rpm. Power transmission is wear-free, as with all hydrodynamic couplings. Power density is further increased thanks to the direct attachment of the TurboBelt to the motor flange, combined with two flow circuits operating in parallel. Compared with traditional couplings, the TurboBelt requires only half as much installation space and is also significantly lighter. Installation and alignment are both simple and quick. Overall, the entire drive is lighter and more compact. This can be beneficial when moving the conveyor system.
The optimised, hydrodynamic power transmission with the TurboBelt offers many advantages to operators of belt conveyors, according to Voith. The very precise control of torque transmission protects the belt, as well as extending its service life. Longitudinal dynamic tension waves in the belt can be effectively avoided. The drive motors run under less strain, so oversizing them is not necessary. Even overloaded belt conveyors can be safely started using this coupling. Unloaded conveyors can be run at creep speed. When combined with reliable mechanics, hydrodynamic power transmission also provides extremely high system availability. The maintenance required is very low with the first overhaul only needed after the first 10 to 15 years. The supply of spare parts is also guaranteed throughout the entire product service life.