While high-capacity overhead cranes are of an impressive size and technical complexity, their smaller and simpler cousins – the workhorses of the factory and general engineering workshop – should not be overlooked, says crane and hoist manufacturer Condra Cranes MD Marc Kleiner.

His comments followed a series of recent orders from Platreef Mine, for installation at the Number Two Shaft, part of the Platreef platinum group metals project near Mokopane, in Limpopo.

The orders range from a large 40/5 t double-girder headgear crane, smaller single- and double-girder cranes, hoists and crawls to more than nineteen chain blocks, including a 2 t explosion-proof chain hoist.

“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,” said Kleiner in a statement to Engineering News & Mining Weekly.

The standout machine for Platreef remains the very large headgear crane – a 40/5 t double- girder electric overhead travelling giant spanning 17 m, which will itself weigh almost as much as its 40 t 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 m.

The order was placed by Ivanplats itself.

Kleiner further emphasises the importance of a long list of other overhead cranes and hoists ordered from Condra for Platreef by consulting engineers Dowding Reynard & Associates.

“These are all workhorses. Even the smallest 2 t 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 t single-girder overhead crane for the mine’s filter building followed soon afterwards, with a 10 t 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 backup.

“Compared with the headgear crane, these are simpler, more straightforward machines, but each one meets an important requirement,” Kleiner says. Elaborating on the headgear crane itself, he states that design challenges had included the delivery of above-average lifting speeds over the very high lifting height of 94 m.

The 40 t main hoist will travel at up to 8.4 m a minute, and the 5 t auxiliary hoist at up to 12.2 m a minute. Both speeds are variable.

Kleiner notes 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 the lowest possible cost to the customer.

“We replaced the normal one-piece end- carriage with a double-bogey design. This will allow a 35 t 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 Canada-based Ivanhoe Mines’ South African subsidiary Ivanplats, and comprises three vertical production shafts, two ventilation shafts, a concentrator and associated supporting infrastructure.

Starting this year, mine production will tap a 26-m-thick flat orebody extending over several kilometres to deliver 12 megatons a year over a lifespan of three decades.

This will position Platreef among the largest platinum group metal mines in the world. Yearly yield is expected to exceed one-million troy ounces of palladium, platinum, rhodium and gold, as well as useful quantities of nickel and copper.