Engineered transport provider Mammoet has replaced an ageing ball mill at one of Australia’s largest alumina refineries.
The mill was located at the centre of the plant, making access challenging due to narrow clearances. Xtreme Engineering partnered with Mammoet to provide a solution for the removal and replacement of the mill, all while minimising disruptions within the live plant.
With no as-built drawings available, Mammoet utilised a point cloud scan, provided by the customer, to generate an accurate representation of the plant in its current state within its proprietary Move3D engineering software. In combination with traditional 2D drawings, Mammoet was able to meticulously plan every aspect of the operation, considering the mill’s challenging location with tight clearances and limited accessibility.
Given the spatial limitations within the work areas, the use of hydraulic cranes or gantries was not viable. A ‘jack and pack’ system was therefore utilised. This involved SPMTs with strategically positioned cassette towers. Four internal towers were placed on the SPMTs, and four external towers positioned on the ground adjacent to the trailers. By adding or removing jacking cassettes, the team could control the height of the mill by redistributing the load between the internal and external towers via the SPMT’s hydraulic suspension.
The process commenced with the removal of the ageing mill. The internal cassette towers were pre-assembled to a specific height on the SPMT, which was then manoeuvred underneath the mill and then raising it until the mill was clear of its foundation.
The SPMTs then transported the mill off site, navigating the congested areas. The process was then reversed to install the new ball mill.
