By rosebell
A mining tunnel boring machine (TBM), which recently came off the production line in Changsha, Central China’s Hunan Province, has been exported to Africa by China Railway Construction Heavy Industry Corporation Limited (CRCHI), whereas this machine is due to be used in the tunnel construction project for Zambia’s Chambishi Southeast Ore Body.
With an excavation diameter of 5.63m, a length of almost 130m, and a weight of around 800 tonnes,this TBM is the first machine that a Chinese-manufactured mining TBM has been exported to the African continent and it also features a minimum horizontal turning radius of 50m and can operate on gradients of up to ±15 degrees.
As part of Africa’s first digitised mining initiative, this project involves the creation of a 9.7km tunnel and long stretches of hard rock, fault fracture zones, tight-radius turns, eccentric excavation, long-distance retraction, cage transportation, as well as high geothermal conditions will be the construction challenges of this project.
With the aim of responsing to these complexities, CRCHI’s research and development team introduced several technological innovations that involve modular designs, small-radius turning capabilities, a backup track-free system, auxiliary gripping mechanisms, immediate support systems, and advanced geological forecasting. These features aim to enhance the TBM’s performance in challenging geological conditions.
In order to improving working conditions and support the construction effort, the TBM is also equipped with a customised refrigeration system, a tool monitoring system, integrated office and rest facilities, and other operator-friendly features.
With a total investment of $830m, the project is estimated to have an annual ore mining and processing capacity of 3.3 million tonnes, while producing 60,000 tonnes of copper concentrate annually.
The advantages of the tunnel’s completion will be significantly boosting transportation capacity at the copper mine and contributing to the overall efficiency of the operation, as CRCHI stated.
