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Press Release - Epiroc Powerbit X transforms ground support in Stockholm's Sofia Station

Press Release - Epiroc Powerbit X transforms ground support in Stockholm's Sofia Station

A hundred meters below ground, in the very heart of the Swedish capital Stockholm, the Epiroc Powerbit X is breaking grounds in civil construction with its diamondprotected technology by drilling an astonishing 3 250 meters without changing the bit.   

The transformative civil construction project for the new metro station Sofia, is part of a larger project to expand the subway system in Stockholm. The construction contract is carried out by Epiroc’s customer Implenia, on behalf of Region Stockholm. Playing a key part in their operations are the Epiroc machines: Boltec E10 S, Boomer XE3 and Boomer E2.   

- The Boltec E10 S is a reliable machine that performs well and the installation quality is higher and more consistent compared to manual bolting. One machine/operator can do what four people and four machines did before. But despite an efficient machine, we still have to stop production to change the drill bit every so often, says Kalle Ville Pellinen, operator Implenia   

- Frequent bit changes were slowing us down. We needed a complete bolting solution that could keep up with the project's ambitious goals, adds Daniel Zetterman, Machine Manager, Implenia   

With each drill bit being changed every 60-70 meters; Epiroc introduced Implenia to the Epiroc Powerbit X, with diamond-protected technology, as a solution to reduce drill bit changes and help them increase productivity and overall safety for their operators.   

- We identified the drill bit changes as an area where we could help Implenia increase their productivity and brought two bits to trial. This was the first time we used the Epiroc Powerbit X in a bolting or ground support application, and these two bits have surpassed our all of expectations and the results are remarkable, says Mattias L Andersson, Epiroc Rock Drilling Tools Contract and Sales Representative   

Massive impact on productivity, logistics and safety 

The Epiroc Powerbit X did not only deliver on its targets – the first drill bit managed to reach a staggering 3 250 meters, making this one of the best results the new diamond technology has seen. Not only did the drill bit offer a longer drilling interval, but it also achieved higher penetration rates of up to 0,5 meters per minute more when compared to conventional drill bits.  


Legend:Epiroc Powerbit X after drilling 3200 m 


- With the first bit we were able to drill for up to 11 days without changing bit. This is a game-changer, says Pellinen  

- Safety is very important for us and by being able to drill without interruptions, our operator can stay in the cabin and avoid going outside under the rock. Together with the efficiency of the Epiroc Boltec E10 S, we haven’t had a single incident or accident during these trials, Zetterman adds.   

A paradigm shift in bolting operations 

The extended lifespan and higher penetration rate of Epiroc Powerbit X has helped Implenia increase their productivity. Furthermore, the environmental impact is what really stands out as the two Epiroc Powerbit X drill bits have saved up to 58 bit changes during the trial alone.   

- The longer lifespan of Epiroc Powerbit X has simplified our logistics. Normally we would have to re-grind a standard bit 4-5 times to reach 400 - 500 meters. As we don’t do regrinding on site – this means substantial savings in transportation (in city traffic) and handling from staff. A huge advantage for us, Zetterman noted.   

The Journey Continues 

Moving into the autumn, both companies are eager to continue the trials and the next stage is to equip both the Boomer XE3 with Epiroc SR38 (48mm bits) and the Boltec E10 S with and Epiroc SR35 (45mm bits).   

For more information, please contact: Sandra Almqvist Project Manager – Brand Communication Epiroc Rock Drilling Tools sandra.almqvist@epiroc.com. Visit https://www.epiroc.com. 41/23.