Tag Archives: Shaft Boring Cutterhead

Herrenknecht making headway on hard-rock mechanised shaft sinking operations

Herrenknecht used the Bauma 2022 stage last month to reveal details about its latest mechanised shaft sinking solution for mining, the Shaft Boring Cutterhead (SBC).

The company, which has successfully delivered its Shaft Boring Roadheader (SBR) to soft-to-medium rock sinking applications in mining, has equipped its latest concept for hard rock up to 250 MPa uniaxial compressive strength (UCS), with the machine able to carry out cutting, lining and mucking operations concurrently.

The SBC’s specification is based on the experiences from six past mechanised shaft sinking projects and was developed in tandem with a global shaft sinking company Redpath Deilmann.

Two of the projects that influenced the design used the SBR – the blind sinks at BHP’s Jansen mine in Canada and Slavkaliy’s Nezhinsky mine in Belarus. The company has also supplied two SBRs to Anglo American’s Woodsmith mine, with one already carrying out sinking operations.

Redpath Deilmann operates SBR shaft sinking operations at Woodsmith, with DMC Mining previously in charge of sinking operations at the Jansen project.

“This new generation of blind shaft machinery aims to update and adapt existing technology to current conditions and requirements,” Martin-Devid Herrenknecht, Member of the Board of Management, says.

Speaking in Munich in a presentation titled ‘Mechanised sinking of deep shafts in hard rock’, Patrick Rennkamp, Product Manager Mining, Herrenknecht, said the SBC had been designed for shaft diameters up to 9 m and shaft depths of circa-1,500 m. The machine weight starts from 450 t and it is 45 m in length.

One of the unique elements Rennkamp highlighted was the pneumatic mucking system on board the SBC.

Building on a similar system used for the SBR, the mucking process on the SBC is tied to the circular motion of the cutter discs situated on the full-face cutterhead. The movement of the discs and suction, combined, ensures the machine only cuts the material once, Rennkamp explained to IM on the side lines of the event, reducing wear on the cutters and keeping the machine cutting for longer.

The design ensures that the cut material filters into the centre of the machine where the suction element is most effective. The cuttings then go up the suction pipe into a suction box before being filtered into coarse and fine material and blown further upwards where they can be transported to another overhead station for removal – via buckets – to surface.

Like the SBR, the machine has a gripper system to keep it in place within the shaft. There is also a lining area directly above the grippers and further work decks for concurrent work.

The company is targeting sinking rates of 6-8 m/d with the new SBC. While this is short of the progress traditional TBMs make in horizontal developments, it is quicker than traditional drill and blast methods used for blind sinking.

Herrenknecht had a team of some 40 working on the development of the SBC at its Schwanau facility in Germany. This is complemented by a team at Redpath Deilmann’s facilities in Germany, who are also providing input to the project.

To this point, the company has carried out 600 tests with different sizes of material, completing some 9 m of shaft sinking in 30-40 MPa UCS concrete with a demonstration rig that is 1:3 the size of the full-size machine.

The next steps are to invite potential customers to supply their own material for testing on the rig and validate the hard-rock cutting potential.

Redpath continues mechanised sinking evolution with S20+ deployment at Odyssey

Redpath is continuing its focus on mechanised shaft sinking operations, with the latest example being the planned use of the hydraulic shaft mucker S20+ at the Canadian Malartic Partnership’s (CMP) Odyssey gold project in Quebec, Canada.

Redpath Canada was recently contracted by the CMP to sink a 6.5-m diameter, 1,800-m deep concrete lined shaft at Odyssey, a project that has the potential to become one of Canada’s largest and most technologically advanced underground gold mines.

CMP, which is 50:50 owned by Yamana Gold Inc and Agnico Eagle Ltd, previously laid out plans to extract 19,000 t of ore at an estimated grade of about 2.75 g/t gold and roughly 5,000 t/d of waste rock during peak operations at Odyssey. The ore will be processed at the operation’s existing plant, which will eventually be adapted to the future mine’s needs including shifting from 57,000 t/d to 20,000 t/d. The ore will be hauled to surface using Blair production hoists with use of both shaft bottom and mid-shaft ore handling systems.

The sinking concept at Odyssey includes the use of the S20+, which was built by Redpath Deilmann in Germany. A previous iteration of this machine, the S20, was used with success on four shaft projects in both soft rock – with an integrated tool package – and hard rock.

The S20+ offers similar capacity/productivity to a North American pneumatic telescopic boom mucker but with a much easier learning curve for operators, according to Kevin Melong, Vice President – Shafts and Technical Services, at Redpath Canada.

Unlike the RD S100, which can move independently of the galloway within the shaft via a telescopic boom, the S20+ is connected to the galloway, requiring the lowering of the galloway to move the mucker into position for mucking.

Melong added: “The S20+ does present some potential for concurrent mucking when in and around the shaft station construction/excavation, but, in general, does not act independent of the stage as in the S100 design.”

Fitted with a bucket as standard, the S20+ offers a maximum digging depth of 7.96 m and a bucket volume of 560 litres. It also offers good flexibility, with the bucket capable of six rotations per minute.

Alongside the S20+ and the aforementioned S100, Redpath has been mechanising the shaft sinking process in mining through the use of large-diameter raiseboring equipment and operation of Herrenknecht’s Shaft Boring Roadheader (in soft-to-medium rock). The company is also working with Herrenknecht on the development of the Shaft Boring Cutterhead, a machine developed for medium-to-hard rock applications up to 250 MPa UCS.