Lengthy increase bore shafts require intensive planning, expert operators and dependable drilling instruments. Combining these components can result in outstanding achievements, reminiscent of breaking the Scandinavian report by drilling a +700 m air flow shaft in a single move.
At Zinkgruvan Mining, the southernmost mine in Sweden, Drillcon Group commenced the increase bore venture for air flow shaft quantity 5 in April 2024. This shaft is the second of two parallel shafts, and a part of the Dalby mine enlargement. The increase bore operations adopted a standard method, beginning with a +700 m pilot gap down after which reamed again up 700 m with a 4.1 m reamer. Nonetheless, the instruments offered by Sandvik have been something however typical. The Drillcon group utilised the newly launched and progressive Sandvik RR890 pilot bit, the newest design of the 12EL reamer head and modernised cutters outfitted with patented PowerCarbide® know-how.
“Finishing a full increase while not having to interchange the cutters or service the reamer is a outstanding achievement, and we’re thrilled to have the Sandvik increase boring group supporting us in making this occur,” mentioned Jonas Myrzell, Manufacturing Supervisor Increase Boring at Drillcon Group.
The revised increase boring instruments are a part of Sandvik’s dedication to providing premium high quality, long-lasting and high-performing merchandise to its international clients. By incorporating the newest progressive know-how, together with complete assist and repair, Sandvik says it ensures its clients can hold drilling effectively.
“We’re thrilled with the profitable increase boring outcomes Drillcon achieved on this venture, and the excessive expectations we had for our optimised increase boring instruments have been met,” mentioned Russell Clayton, Product Supervisor Increase Boring at Sandvik Rock Instruments. “Our new Sandvik RR890 pilot bit options PowerCarbide® inserts, full leg safety and a patented dual-seal curler bearing to increase service life and allow extra even rock breaking. Along with Drillcon, we additionally trialed our upcoming era of cutters outfitted with PowerCarbide® inserts, focusing totally on enhanced put on resistance and lengthening service life. We additionally upgraded our commonplace reamer head mannequin primarily based on discipline expertise on the whole, and shut collaboration with Drillcon, to fulfill the particular wants of this increase.”
The outcomes converse for themselves, and calculations by Drillcon confirm the profitable outcomes. The pilot bit confirmed a 69% improve in efficiency in comparison with earlier Sandvik variations, and the reaming lasted a whole 700 m move with out altering a single cutter.
Operators described the person expertise of the up to date increase boring instruments as easy, dependable and constant, with glorious monitoring of the drill plan by way of metre development per day.
“Our high precedence for all increase bore operations is to offer a safer work atmosphere for everybody concerned, whereas additionally making certain steady pace and progress, and sustaining a cheap method all through all drilling steps,” Myrzell mentioned. “With the instruments from Sandvik lasting a full +700 m increase, we will confidently tick all of the packing containers. Not solely did we save over three weeks in service time, however we additionally averted having our operators underground, mitigating the dangers related to instrument modifications, heavy tools dealing with and potential hazards from falling rocks.”
