HIGH-capacity overhead cranes often make headline news because of impressive size and technical complexity. Their smaller and simpler cousins – workhorses of the factory and general engineering workshop – should not be overlooked.
This is according to Marc Kleiner, MD of crane and hoist manufacturer Condra. He was commenting on a slew of recent orders taken for Platreef Mine, ranging from a giant 40/5-ton double-girder headgear crane, through smaller single- and double-girder cranes, hoists and crawls, to no fewer than nineteen chain blocks, including a 2-ton explosion-proof chain hoist.
All are for installation at Platreef Mine’s Number Two Shaft, part of the Platreef PGM project near Mokopane, Limpopo Province, South Africa.
Often the go-to company for buyers seeking proven ability at the more complex end of the technical design spectrum, these orders highlight Condra’s capabilities in smaller and more standard lifting equipment. Nevertheless, the standout machine for Platreef remains the very large headgear crane: a 40/5-ton double-girder electric overhead travelling giant spanning 17 metres, which will itself weigh almost as much as its 40-ton maximum load.
Murray & Roberts Cementation supplied the procurement recommendation for this machine, which will install and maintain the shaft’s headgear-mounted winders and sheave wheels, raising and lowering component parts over a lifting height of 94 metres. The order was placed by Ivanplats itself.
Switching to a long list of other overhead cranes and hoists ordered from Condra for Platreef by consulting engineers Dowding Reynard and Associates, Kleiner emphasised their importance.
“These are all workhorses,” he said. “Even the smallest 2-ton explosion-proof chain hoist will play an important role.”
Condra’s first deliveries to Platreef took place in late 2023, comprising a short-headroom hoist for the mine’s tailings filter, and a K-Series hoist for the mill feed conveyor. Both are being used for maintenance work.
A 5-ton single-girder overhead crane for the mine’s filter building followed soon afterwards, with a 10-ton double-girder overhead crane for the plant workshop. One of these machines was dust-ignition-proof rated to ATEX Zone 21/22 standard. Control of both is by radio remote with manual pendant back-up.
“Compared with the headgear crane, these are simpler, more straightforward machines, but each one meets an important requirement,” Kleiner said.
Elaborating on the headgear crane itself, Kleiner explained that design challenges had included the delivery of above average lifting speeds over the very high lifting height of 94 metres. The 40-ton main hoist will travel at up to 8,4 metres per minute, and the 5-ton auxiliary hoist at up to 12,2 metres per minute. Both speeds are variable.
Kleiner explained that the modularity of Condra’s hoist range had made it possible to accommodate the Platreef specifications, with careful design of the crane’s end-carriages facilitating installation at lowest possible cost to the customer.
“We replaced the normal one-piece end-carriage with a double-bogey design,” he explained.
“This will allow a 35-ton tower crane to lift the headgear crane into position one girder at a time. Without the doubled-bogey arrangement the entire crane would have had to be lifted into position as an assembled unit, a more difficult operation.”
Other features of the headgear crane include an automatic storm brake to counter wind loading, a full-length work platform, and radio control with mobile pendant back-up.
Platreef has been under development since 2020 by Ivanplats (Canada-based Ivanhoe Mines’ South African subsidiary), and comprises three vertical production shafts, two ventilation shafts, a concentrator and associated supporting infrastructure.
Beginning this year, mine production will tap a 26-metre-thick flat ore body extending over several kilometres to deliver 12 megatons per annum over a lifespan of three decades, positioning Platreef among the largest platinum group metals (PGM) mines in the world. Annual yield is expected to exceed one million troy ounces of palladium, platinum, rhodium and gold, plus useful quantities of nickel and copper.
