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May 2015
MODERN MINING
25
COMPANIES
Master Drilling has established itself on site
at PMC and has already completed the 30 m
presink on the first shaft, a task which took just
two months. It expects to complete the shaft in
the second half of 2016.
According to Master Drilling’s founder and
CEO, Danie Pretorius, raise boring will deliver
the shafts at a fraction of the cost – less than
20 % – of conventional blind-sinking methods
and very much faster as well. He also pointed
out to
Modern Mining
that when the machine
is operated from an above-ground control room,
there will be almost zero exposure to safety haz-
ards. “We will only need a team of two people
to operate the RD8 when the rig is fully mecha-
nised in the near future,” he said. “Compare
this with the situation you have with conven-
tional shaft-sinking where you might have 15
or 20 people – or more – working within the
actual shaft barrel and blasting occurring on a
daily basis with all that this implies in terms of
exposure to risk.”
Master Drilling’s Executive Director Koos
Jordaan added that the contract for two 6,1 m
diameter and 1,2 km deep ventilation shafts
ranked as one of the largest yet undertaken by
the company. “There have been plenty of shafts
raise bored in recent years in South Africa and
elsewhere but none with quite this combina-
tion of depth and diameter,” he said. “The
largest diameter we’ve ever done up till now is
7,3 m but not to this depth and the deepest hole
Executive Director Koos
Jordaan with the new
horizontal boring machine
to be deployed at a Sibanye
mine in the background.
The machine is essentially a
tunnel borer based on raise
boring technology.
machine
to its raise boring fleet