When dry-type transformer specialist Trafo Power Solutions was asked to supply three units to an underground South African gold mine, it was given a hill to climb in terms of design and logistics.
The mine required the transformers to operate in the usual demanding conditions of dust, moisture and heat, says Trafo Power Solutions managing director David Claassen. However, there were a range of other challenges – not least the weight and height restrictions of a deep mine. While two of the transformers are relatively small – 250 kVA and 630 kVA – the third is a substantial 3150 kVA.
“The transformers are to operate at about 1km below surface, and will have to be transported through both an incline shaft and vertical shaft,” says Claassen. “Especially with the larger unit, we had to work very 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 manner that would allow them to be transported in manageable components before being re-assembled underground. The enclosure design had to ensure that while dust and moisture were kept out, there was still enough air circulation to cool the unit. The dry-type transformers will be supplying loads for a refrigeration plant.
“Trafo Power Solutions conducted the complete designs, which were then verified and vetted by TMC,” he says. “This quality control is central to our approach in ensuring fit-for-purpose solutions.”
He emphasised that the design and manufacture of the units was 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 undermine these forecasts.”
Meeting delivery expectations goes hand-in-hand with the efficiency and reliability of Trafo Power Solutions’ offerings, he explains. These factors contribute significantly towards total cost of ownership, which is of utmost importance 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, particularly the 10-tonne mass of the large 3150 kVA unit.
Delivery of the transformers is expected to take place by the fourth quarter of 2022, with Trafo Power Solutions supervising the installation and commissioning process.
