According to the company, this was the first major mechanical task in completing the infrastructure required to execute the shaft sinking works that will commence in February 2020. The works will progress down to a depth of just over 1,100m over the next 18 months.
The overall Oyu Tolgoi project is an operational gold mine located in the southern Gobi desert of Mongolia, approximately 550km south of the capital, Ulaanbaatar. GCR Mongolia's contract for sinking shafts 3 and 4 includes the construction of two shafts that will provide additional air ventilation into the existing tunnels of the operating mine. The increase in air will allow for an expansion of the underground mining operation for future production. After a process of concrete lining, the shafts will be 10m and 11m in diameter respectively.
Site establishment commenced last October and GCR Mongolia started with civils and construction of the pre-sink, which is the initial part of the shaft that the stage has been lowered into. Since June this year, the team has been busy erecting the structure of the headframe and buildings for services that support the sinking works. Both facilities, nearly 800m apart, are designed and constructed to facilitate execution during the winter months when temperatures drop to -40°C.
The stage is 25m in length and comprises of five decks, with the fifth deck being a floating (moveable) deck where most of the shaft work will be completed. When the floating deck is fully extended, the total length will be 31m and it will weigh 212t. This lift was preceded by a load test of 325t to attain approval for using the crane and its rigging, the largest lift ever conducted at the Oyu Tolgoi site.
Greg Kember, project director at GCR, said it has been a challenging but enjoyable journey so far after the team commenced work on the contract for the Oyu Tolgoi project in Mongolia 15 months ago.
"Our engineering and procurement efforts have combined worldwide resources and culminated with our design team operating from our Ulaanbaatar office," he commented.
"Our team, with over 1,100 individuals, has done an absolutely amazing job communicating and coordinating their respective works to achieve these tasks safely and on schedule. Now we turn our attention to the remainder of the lifts and E&I commissioning activities."