Supplying three dry-type transformers to go 1.6 km underground at a South African gold mine presented a range of design and logistical challenges to dry-type transformer specialist, Trafo Power Solutions. Taking these on, the company has designed a practical solution for even the large 3 150 kVA unit in the order, accommodating the strict weight and height restrictions applicable without compromising performance and reliability.
The transformer units are designed so that they can be transported in manageable components and reassembled underground.
The mine required the transformers to operate in the typically demanding mining conditions of dust, moisture and heat, says Trafo Power Solutions Managing Director David Claassen. However, there were other project-specific challenges – including the weight and height restrictions that come into play in a deep mine. Although two of the transformers are relatively small – 250 kVA and 630 kVA – the third is a 3 150 kVA unit.
“The transformers are all required to operate at about one kilometre below surface and will have to be transported through an incline shaft and a vertical shaft,” says Claassen. “Especially with the larger unit, we had to work closely with our Italian technology partner TMC, to reach a design that could be moved within these constraints.”
Trafo Power Solutions also designed the enclosures locally, in a way that would allow for them to be transported in manageable components before being reassembled underground. In designing the enclosures, it had to ensure that while dust and moisture are kept out, there will still be enough air circulation to cool the units. The dry-type transformers will be supplying loads for a refrigeration plant.
“Trafo Power Solutions handled the complete designs, which were then verified and vetted by TMC,” Claassen says. “This consistent standard of quality control is central to our approach in ensuring fit-for-purpose solutions.”
He adds that the design and manufacture of the units have been carried out according to schedule and they are on track to be supplied within the customer’s required timeframes.
“On-time supply is an increasingly important aspect of success for mining companies,” he says. “Mines’ capital expenditure is planned according to the expected returns on any project, and supplier delays can invalidate these forecasts.”
Meeting delivery expectations goes hand-in-hand with the efficiency and reliability of Trafo Power Solutions’ products, he says. These factors contribute significantly to total cost of ownership, which is particularly important to mining customers.
Trafo Power Solutions also designed the specialised skid bases for the transformers, to facilitate moving the units to their operating destination. These accommodate the considerable weight of the units, notably the 10-ton mass of the largest unit.
Delivery of the transformers is expected by the fourth quarter of 2022. Trafo Power Solutions will supervise the installation and commissioning process.
For more information visit: https://www.trafo.co.za/
