DRIVE options for conveyors have been significantly broadened as a result of some recent innovative design work done for BHP’s Appin Colliery in the Illawarra region of New South Wales. The collaborative effort — involving Gulf Conveyor Engineering, SEW-Eurodrive, G-Man and Voith Australia — delivered a highly versatile drive module configuration.
When Appin Colliery decided recently to invest in further drives underground to develop productive coal seams, it approached Gulf with a tall order. So tall in fact that Gulf presented the formidable brief to SEW-Eurodrive in conjunction with G-Man and Voith as well as other noted transmission suppliers.
What was required was a system which could be a standard drive, suitable for various different conveyors, and suiting the needs of each at the same time. Some conveyors were to be a single drive and then upgraded to multiple drives at a later date, and others were intended as multiple drives in the first instance. The concept would also be applied to tripper drives. Control of the drives was essential, as was proper load sharing. The drive had to be low on maintenance and highly reliable with a minimum of components and a minimum of complexity. A further requirement was the main items of equipment were to be carried as stock and had to have a favourable initial cost.
“The specification was tough, but certainly not impossible,” said Stephen Koen, a SEW-Eurodrive project engineer. “What made it particularly challenging is that we were up against some other well known suppliers of hydro-viscous clutch couplings and drives.
“But a powerful motivator was that, after discussions with Gulf, we could all see the opportunity of developing a system suitable for many different conveyor and tripper applications and not exclusively for use underground at Appin Colliery.”
Space saving was a special consideration for this application, as some alternative methods of low speed hydro-viscous clutch drives use parallel shaft helical reducers. Therefore a substantial cut away at the conveyor drive head was required to accommodate the wider drive.
“We use a bevel helical reducer, meaning that we could get away with a minimum (if any) additional cutting to fit the drive heads in place,” Koen said. “This also allows us to relocate our drives very simply, and avoid the cost as well as time when an installation or relocation is required.”
The G-Man/SEW-Eurodrive/Voith/Gulf drive configuration comprises the Voith DTPPW fill controlled fluid coupling, which has many advantages including the fact that it uses mine pit water rather than expensive hydraulic fluids that have to be changed frequently and regularly. Voith felt using mine water would not only culminate in considerable cost savings on ultimate maintenance, but would represent a non-toxic, environmentally friendly fluid solution.
Due to the design of the DTPPW controlled fill fluid coupling, Appin could have an unrestricted number of starts per hour. G-Man’s design also flanged-mounted the electric motor to the Voith fluid coupling and then flange-mounted the fluid coupling to the input of the SEW-Eurodrive reducer.
“This means that alignment is no longer a problem, either in assembly or during maintenance on the surface or underground,” Koen said.
Also offered is a skid under the drive, not competing with the flange mounting for rigidity in the drive, but providing a convenient location for the torque arm. It also has a mounting surface for wheels which allow the complete drive to be towed underground and then positioned conveniently for installation. Again, this represents significant savings in installation, and maintenance if and when required.
