Two 1250 HC 40 Litronic tower cranes have been mounted on foundation anchors at the “Minera Escondida” copper mine in Chile (Fig.). During the initial phase the tower cranes will be used for extension work and to build the mine infrastructure. The tower cranes handle loads of up to 20 tonnes which they master without any problem. After the construction phase has been completed the two Liebherr tower cranes will be used for maintenance purposes.
A total of three 1250 HC tower cranes are in use at the “Minera Sierra Gorda” copper mine. Two of these cranes are the 50-tonne version and the third is the 40-tonne version. All three cranes have been mounted on foundation anchors and erected in similar configurations. During the construction phase the cranes are used as classic tower cranes for effective load handling for the assembly of tanks. During this process loads of 14-17 t per component will be handled. In the long term all three cranes will be used as maintenance cranes in the mine.
The extreme geographical and climatic conditions not only present challenges to the workforce but also to the crane equipment. The high temperature differences of up to 40°C between night and day and the dust created by the arid desert climate produce extraordinary stresses. In addition Chile is one of the most earthquake-prone countries on Earth where earthquakes up to a magnitude of 5 are by no means a rarity. This means that all the cranes must comply with a Chilean standard which ensures that they are resistant to earthquakes.