Modern Mining June 2016

TECHNOLOGY

New shaft boring technology

German engineering company Herrenknecht AG, a world leader in mechanised tunnelling, has developed a range of four shaft boring machines – each designed to operate in specific geological conditions – for the safe and rapid construction of blind shafts or shaft enlargements to 2 000 m. Currently, work is progressing on BHP Billiton’s Jansen potash project in Saskatchewan, Canada, on the sinking of two 1 000 m deep mine shafts using this pioneering blind shaft technology.

T his is the first time in over two decades that such technology has been employed in mine shaft sinking, accord- ing to Danie Roos, Herrenknecht AG’s Busi- ness Development Manager in South Africa. Safety issues, rising operational costs and a re- duction in productivity have resulted in mine operators taking a fresh look at the way mines are run – which has resulted in renewed inter- est in the mechanisation of mining operations, including shaft sinking, says Roos. “The excavation of shafts is a critical activity in the development of new mines, or the exten- sion of existing ones, because the quicker an

orebody is accessed, the sooner the end product enters the market. “Mechanised deep shaft boring is regarded as a game-changing technology and supports the universal drive to replace drilling and blast- ing with alternative technology that removes miners from potentially dangerous areas, like a shaft bench with an unsupported shaft wall,” he says. The largest machine in the Herrenknecht range is capable of developing shafts in hard rock conditions to depths of 2 000 m. This machine, referred to as the Shaft Boring Machine (SBM) , was developed as a result of Herrenknecht’s involvement in Rio Tinto’s ‘Mine of the Future’ programme and the

Danie Roos, Herrenknecht AG’s Business Development Manager in South Africa.

Two of Herrenknecht’s Shaft Boring Roadheaders (SBRs) are currently in operation at the Jansen project in Can- ada. The SBR is equipped with a rotating cutting drum installed on a telescopic and slewable boom.

20  MODERN MINING  June 2016