Volvo Construction Equipment has adapted one of its pavers for underground applications at the world’s largest iron ore mine.
The Volvo CE P7820C tracked paver has been operating at approximately 1.5km beneath the Earth’s surface in the Arctic town of Kiruna, helping to lay the mine’s 400km underground road network.
The unit is being leased by contractor, NCC Roads, on behalf of Sweden’s state-owned mining company, Luossavaara-Kiirunavaara Aktiebolag (LKAB).
“We used to work with a wheel-equipped paver,” explained Mathias Enlund, foreman at the mine.
“But now, we never get stuck because this machine is track-equipped and very reliable. The work doesn’t get held up and it’s reassuring that it’s equipped with a clean combustion engine with low noise and efficient fuel consumption,” he added.
Enlund and his colleagues work four days per week for the entire summer season, from May to October. The asphalt, which is mixed at a site located 17km away from the mine, is laid between June and September.
The Volvo CE P7820C tracked paver was selected by NCC Roads due to the nature of the underground paving applications at the site. As almost all of the paving is uphill, the team needed a machine capable of pushing 55-tonne mining trucks up 7% gradients. Volvo CE and its authorised dealer, Swecon, were able to deliver the bespoke paver to the mine within 10 days of the initial order being placed.
“The P7820C had to be adapted to suit the particular conditions that exist down the mine,” commented Svante Bodare, a product specialist for road machinery at Swecon.
“The underground tunnels are dark, the ceilings are low, and the roads have a near constant gradient of 7%. So, we removed the roof of the paver, the exhaust was shortened, and extra lights were mounted on the machine.
“In this country, 98% of paving is done above ground with wheel-equipped machines. We also tend to transport those machines between job sites with the help of trucks, but in the mine, they drive the P7820C between the paving sites,” he said.
Johan Pettersson, NCC Roads’ site manager, said that the tailored paver made all the difference to his team’s work.
“When the equipment is unreliable, it really raises everyone’s pulse,” he noted.
“This paver provides a whole different sense of confidence that we can carry out the work efficiently and without disruption.
“We’re currently leasing the machine from Swecon, and since they have a workshop here in Kiruna, the service is excellent. They can send out specialist service personnel fairly quickly, which makes a huge difference. In the past, we used older machines, and the closest service staff were located in Umeå, seven hours away,” Pettersson added.
In addition to laying the massive underground road network, the Volvo CE paver is also being used in the construction of underground offices, service stations, and garages. Iron-ore extraction is currently taking place at 900m, but the P7820C has been down to 1,489m.
“Around 20,000 tonnes of asphalt [have] been laid underground this year, which is probably the largest amount ever in the history of an underground mine,” said Pettersson.
“We would like to keep using the Volvo paver as it will be useful for road maintenance and there is a constant market underground,” he concluded.
