Nuna offers customized vertical cutting services to meet our mining clients’ specific needs.
Diaphragm wall techniques have changed civil engineering significantly since the mid-1980s. The introduction of the vertical cutter technology has played a key role in this development. The use of vertical cutters has pushed the boundaries of this technique continuously further and further. Increasing wall thicknesses became possible, and the technique was able to advance to ever-greater depths after the long hoses had been transferred onto vertically mounted hose reels.
Kimberlite Bulk Sample Program
In partnership with Bauer Maschinen GmbH, Nuna has introduced the Bauer BC 50 cutter on a MC 128 duty-cycle crane to the mining industry. The Bauer BC 50 will be the first cutter in the world used to cut to a depth of 250 metres in a commercial application.
The cutter face measures 3.2 metres by 1.5 metres, which results in a theoretical cut of 4.8 square metres per metre of advance. The equipment consists of a standard Bauer MC 128 crane upgraded for an ultimate depth of 250 metres, with a custom Bauer BC 50 cutter modified for additional pump capability and increased weight to 70 tonnes. The cutter slurry is transported via an HDPE piping system to a centrally located Bauer BE 550-20 separation plant. The separation plant will produce kimberlite product in two gradations, coarse and fine, and a discharge stream of bentonite slurry. The kimberlite products above the determined cut-off are then washed, bagged, transported, and off-loaded at the plant recovery location.
The separation plant discharge bentonite stream is then pumped back to the hole. A bentonite pond adjacent to the separation plant is sized to accommodate a full loss of circulation in the hole with reserve capacity. This pond replenishes the separation plant automatically to maintain the level in the bentonite return tank. Bentonite losses occur during bulk sampling, and these losses — and subsequent replenishing — maintain the bentonite quality in the hole. The bentonite is pumped from the separation plant tank back to the hole to maintain the bentonite level in the hole.