Condra says it has developed fully automated overhead crane capability, with the first machine of this type recently delivered to a South Africa platinum group metals operation.
Marc Kleiner, Condra’s Managing Director, said the company was making full use of new developments in sensors, controls and software to offer a very precise positioning capability in automated applications, with the company aware of an industry shift towards more automated operations.
“This is a capability that we will offer to our customers as an option,” Kleiner said. “We will mainly, but not solely, target the copper mines, especially tankhouse and copper-leaching applications where we have extensive experience.”
Condra’s announcement follows the increasing sophistication of its semi-automated installations, which began in 2003 with a grabbing crane installed at a Durban spice company to pick spices and transport them to specific points for release over hoppers, the company said.
At Sibanye Stillwater’s Marikana platinum mine (owned by Lonmin prior to Sibanye-Stillwater’s acquisition of the company), the fully-automated machine recently installed and commissioned is a 16 t, 16 m-span double-girder electric overhead travelling grabbing crane. It features a customer-specified mechanical rope grab in place of the hydraulic alternative to deliver the improved durability of mechanical operation within Marikana’s abrasive operating environment, Condra said.
There are dual hoists in the design; one to raise and lower the load, the other to mechanically close the grab by means of an internal sheave arrangement to overcome the spring-loaded open state.
Variable speed drives are fitted throughout the crane, delivering maximum speeds of 10 m/min on the lift, and 20 m/min and 40 m/min on the cross-travel and long-travel respectively. Four long-travel motors deliver the materials handling equivalent of four-wheel-drive, enabling automated control of all four wheels for precise crane positioning accurate to within 5 mm.
The crane is fully automated with a manual override, according to Condra, and is programmed by an operator from a remotely located control room, where on-screen monitoring is complemented by visual monitoring capability via closed-circuit television.
Condra’s fully automated option applies across the company’s product offering of single girder and double-girder overhead travelling cranes, gantry cranes, bridge cranes and cantilever cranes for markets worldwide, it said.
These machines go up to heavy duty Class 4, with a focus on product quality and reliability to the standards of ISO, GOST and other internationally recognised quality control bodies, Condra said.
Two lines of hoists are manufactured in several standard models suited to most mining, industrial and general applications, from 1 t to 500 t, with motors bought from external suppliers.