Modern Mining May 2016

CRUSHING, SCREENING AND MILLING

Osborn rotary breakers find favour in coal

T wo recent orders for Osborn rotary breakers reflect the con- tinued demand for these robust, reliable machines in the coal industry, says Osborn Engineered Products. The Elandsfontein-based equipment manu- facturer has supplied a rotary breaker to a new customer in the Kriel area and has secured an order from a coal mine in Secunda, says product sales special- ist Etienne Swanepoel. “At the Kriel coal mine, our customer has installed a 3 600 mm x 6 700 mm Osborn rotary breaker to optimise the performance of his plant, remove rock and contamination, and increase the operation’s yield. This machine has a design capacity of 1 350 tons per hour, but our customer is running it at 500 tons per hour.” Osborn supplied, installed and commissioned the new machine, including the chute work and the support structure, Swanepoel adds. He contends that this mine, like many others, recognises the value of an ‘old classic’ like the rotary coal breaker.

“For rock removal, rock and coal separation, the rotary breaker is the best machine for the job. This tough, hardworking unit has come back into favour in the coal mining industry in recent years, and it is once again making its mark as the most efficient machine for use in ‘dirty’ coal mining environments, where there is a lot of rock in the run-of-mine material.” Explaining the rotary breaker’s operation, Swanepoel says it works on a gravity method to break coal in a very efficient manner through attrition. “Material is continuously introduced at the feed end, repeatedly raised by the lifters and dropped until it is broken to size and falls through the perforations in the screen plates to a collection hopper below. “Any hard rock present in the feed material assists with breaking the coal during the raising and dropping action. The Osborn rotary breaker is designed to reduce soft to medium coal and is not entirely suitable for hard coal or coal with a high moisture content. “Mine rock, refuse and other uncrush- able debris is automatically carried to the end of the drum and is discharged through a chute,” Swanepoel continues. “The Osborn rotary breaker’s design incorporates a chain and sprocket drive arrangement which drives a heavy duty reinforced drum. Renewable

perforated plates are fitted around the inte- rior of the drum. Interchangeable lifters and ploughs are bolted on the inside of the drum. Due to variations in the types of coal being pro- cessed, capacities and power requirements will vary from mine to mine.” 

An Osborn rotary breaker in a typical application.

Iron ore mine opts for Metso equipment Metso reports that it will deliver to Sedibeng Iron Ore, a subsidiary of Tata Steel, a stationary crushing and screening solution for its Sedibeng iron ore mine in the Northern Cape. The delivery includes a five-year Life Cycle Ser- vices contract, which will reportedly bring Sedibeng increased production capacity and reliability while reducing production costs. The cold commissioning is scheduled for late 2016, and the plant should be operating at the beginning of 2017. “This complete solution covers services and equipment and thus en- sures planned maintenance and better production reliability for the cus- tomer. For Metso, the order represents a new way of operating in Southern Africa. It increases our installed base in the area and will surely open up new opportunities in the growing market,” says Charles Ntsele, Metso’s General Manager for Mining Sales in Southern Africa. Sedibeng Iron Ore mine has previously been using a Metso mobile crushing and screening solution operated by a sub-contractor. Due to a planned increase in capacity, Tata Steel, the principal shareholder, wanted to investigate the possibility for a stationary plant. The complete order consists of a vibrating feeder, a C130 jaw, a CVB 603 screen, an HP 500 cone crusher, conveyors, electrics and automation, to- gether with the auxiliary equipment. 

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May 2016  MODERN MINING  53