IM 2020 September 20 | Seite 75

SHAFT SINKING “In one shaft, we are about two months ahead of plan and, on the other one, about three months ahead,” he said. “Bottom line: we are pretty confident of completing this project ahead of time.” Martin-Devid Herrenknecht, reviewing the project, added: “Slavkaliy’s bold decision in favour of the SBR’s premier in Europe and Redpath Deilmann’s leading shaft sinking expertise were the ideal environment for the machines to prove their worth and to develop new perspectives of this technology.” Where next for the SBR? The short answer is the Woodsmith mine, in the UK, owned by Anglo American, where two thirdgeneration SBRs will help sink the production shaft to a depth of 1,594 m and the service shaft to 1,565 m depth, both with 6.75 m diameters. The current schedule would see these SBRs start sinking activities at Woodsmith next year. Outside of this project, Greinacher said the SBR project in Belarus had attracted lots of attention from global mining and engineering companies. Earlier this year, the company had arranged an international visit for parties interested in the SBR and the project, only for the event to be scuppered by COVID-19. One Poland-based coal miner was able to visit the project before the pandemic set in and Redpath Deilmann is currently discussing a The SBC features an 8-10 m diameter special shaped cutting head potential contract with the firm using the SBR to sink two shafts in the east of the country, according to Greinacher. “There are perhaps two or three other projects in various stages of discussion,” he said. With Redpath Deilmann holding onto these machines following completion of the work in Belarus and having already successfully carried out a sinking project by mechanised means, it has an advantage over other contractors when bidding for future contracts in terms of both capital expenditure and experience, according to Greinacher. “Worldwide, though, there is way more demand in mechanised hard-rock shaft sinking than in soft rock,” he said. Therefore, in 2018, in cooperation with Herrenknecht, the company started developing a concept for a hard-rock (around 260 MPa) mechanised sinking machine. This concept, the Shaft Boring Cutterhead (SBC), is billed as being able to cut >120 MPa rock down to 1,000 m depths with shaft diameters of 8- 9 m. Greinacher said the experience both companies have with the SBRs has been leveraged for the design and engineering of the SBC. Built with a cutterhead like a tunnel boring machine (TBM), it can deliver an advance rate of 6 m/d, according to Herrenknecht. Greinacher expanded on some of the other features. “It is not that different from the SBR, except in the all-important cutting area, which is like a TBM with 8-10 m diameter special shaped cutting head. “The mucking system – we looked at five or six mucking systems during design – will be a pneumatic system, again like the SBR.” The excavated chips will be sucked at the face to a cyclone some 30 m up, and then discharged into the buckets. With basic engineering now complete, Greinacher said both companies are ready to start jointly marketing and promoting the SBC to the industry. “The next step is to set up a test facility in Schwanau on the Herrenknecht property,” he said. ANY MINERAL. ANY GEOLOGY. ANYWHERE. COMPANY MARKS A NEW MILESTONE WITH ANOTHER SHAFT SINKING RECORD IN BELARUS For more than 130 years we have safely and successfully sunk more than 500 shafts with a depth of over 230,000 m. We are a member of The Redpath Group, operating on all five continents and belonging to the world market leaders in the field of mine contracting and construction. We provide our customers with a complete range of services from design and engineering to construction, maintenance, reconstruction and rehabilitation. Contact us with your shaft-related inquiries. �������� Shaft station level 700 m, Slavkaliy mine Nezhinsky, Belarus REDPATH DEILMANN GmbH Haustenbecke 1, 44319 Dortmund, Germany Tel.: +49 231 2891 395/396 www.redpathdeilmann.com