REGIONAL MILL SHELLS FORGING NEW GROUND

Hofmann Engineering focuses on the production of grinding mill shells.

IN 1969 two brothers from Germany set up a small toolmaking shop in a backyard in Perth. Today their manufacturing business, Hofmann Engineering, employs 150 people in engineering works in Melbourne, Bendigo and Perth. It also has sales offices in North America, South America and India. More than half the products the company produces are exported to the Americas, Europe and Asia.

Hofmann focuses on the development and production of grinding mill shells. A mill shell is a large cylinder made of steel or stainless plate and is used to process ore.

Hofmann can manufacture large diameter grinding mill heads and shells for mineral processing. In 2012 they dispatched their first mega-unit - a mill shell and heads - for the first of three grinding mills at Barrick Gold's Pascua Lama gold-silver mine on the border of Chile and Argentina.

The mill shell is manufactured in three cylindrical cans, each split longitudinally into semicircles for transport. Three even larger mill shells are now on order for another client; and will go to iron ore and copper projects in South America.

"When completed these will become some of the largest grinding mills in service" says Hofmann's product manager Geoff Kinniburgh.

Hofmann has also developed forged steel, rather than cast, large diameter girth gears. The company has been able to do this in part because it has one of the largest heavy fabrication, heat-treatment and machining facilities in Australia. Big mine sites prefer forged steel gears with fine-grained, high-integrity microstructure, as opposed to castings with imperfections.

"We know we've got some of the best engineers and tradespersons in the country working for us," Geoff Kinniburgh says. "We put it down to our focus on training apprentices and retaining our staff."

Hofmann Engineering's Bendigo site, for instance, now employs nine apprentices, all of whom were recruited from regional areas.