XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3787
typical 30 ft, 27 MW ball mill. A selection of illustrations
from the 44 ft SAG mill analysis can be seen in Figure 12
below. In both cases bolt stress differences are low (10MPa)
and contact integrity is maintained.
In addition to the simulation work, geometric checks
have been completed for the designed 44 ft SAG mill and
30 ft ball mill. This included access checks for the first row
of liner bolt and evaluation of clearance between the motor
stator and mill components. This review resulted in head
angle optimization for the proposed 30 ft ball mill design.
This change was required to balance structural stress while
maintaining adequate clearance between the bearing hous-
ing foundation plinth and the stator housing.
Figure 11. Transport dimensions in mm of a 44 ft GMD
CONCLUSIONS
Lower ore grades, the obligation to reduce greenhouse gases,
remote and high-altitude locations, and increased pressure
from shareholders for fast return on investment are just a
few challenges the mining industry is facing.
Large mills and GMDs have the potential to make
low grade and high tonnage deposits economically via-
ble and mining more sustainable. It was shown that one
grinding line with two new generation large GMDs can
replace two lines with four smaller RMDs. This reduces the
space needed for the grinding process and the number of
upstream and downstream equipment and thus potentially
reduces project construction costs. Due to the absence of
pinion and ring gears, GMDs also achieve higher efficiency
typical 30 ft, 27 MW ball mill. A selection of illustrations
from the 44 ft SAG mill analysis can be seen in Figure 12
below. In both cases bolt stress differences are low (10MPa)
and contact integrity is maintained.
In addition to the simulation work, geometric checks
have been completed for the designed 44 ft SAG mill and
30 ft ball mill. This included access checks for the first row
of liner bolt and evaluation of clearance between the motor
stator and mill components. This review resulted in head
angle optimization for the proposed 30 ft ball mill design.
This change was required to balance structural stress while
maintaining adequate clearance between the bearing hous-
ing foundation plinth and the stator housing.
Figure 11. Transport dimensions in mm of a 44 ft GMD
CONCLUSIONS
Lower ore grades, the obligation to reduce greenhouse gases,
remote and high-altitude locations, and increased pressure
from shareholders for fast return on investment are just a
few challenges the mining industry is facing.
Large mills and GMDs have the potential to make
low grade and high tonnage deposits economically via-
ble and mining more sustainable. It was shown that one
grinding line with two new generation large GMDs can
replace two lines with four smaller RMDs. This reduces the
space needed for the grinding process and the number of
upstream and downstream equipment and thus potentially
reduces project construction costs. Due to the absence of
pinion and ring gears, GMDs also achieve higher efficiency