ROCK TOOLS
Autobit is the first drill bit from Sandvik designed specifically for automated longhole drilling
Hanging by a thread
Drill bits for autonomous rigs and automated bit changing were two developments showcased at MINExpo 2021 . Paul Moore looks at these and some other rock tools industry highlights
Automated drill rigs started transforming the industry more than two decades ago , but even today few are used to their full potential due to drill bits that wear out and limit production . The new Autobit , one of the technologies highlighted by Sandvik Mining & Rock Solutions at MINExpo 2021 , seeks to help customers change that through long grinding intervals , enabling drilling to continue during shift changes .
Autobit is the first drill bit from Sandvik designed specifically for automated longhole drilling . It features a greatly increased first grinding interval - more than twice that of standard bits – that can translate to several more hours of drilling every day . This is made possible thanks to a new and innovative bit design and the addition of Sandvik ’ s PowerCarbide™ , the most powerful carbide grade .
“ Autobit addresses a key bottleneck in the automated drilling process : running the drill rig during shift changes ,” said Robert Grandin , Product Manager Top Hammer Underground at Sandvik Mining and Rock Solutions . “ The Autobit now enables customers to significantly increase productivity in their automated drilling operations .” The longer service life and grinding intervals are made possible through the new design features of Autobit , combining a strong gauge row , fully ballistic button profile and carved out front design , as well as the addition of the PowerCarbide™ SH70 grade , part of Sandvik ’ s most innovative carbide technology . Together with the Autobit ’ s design elements , the self-hardening carbide grade can more than double grinding intervals compared to a standard product .
“ Combining our PowerCarbide™ technology with a bit design that maximises the first grinding interval delivers remarkable outcomes ,” Grandin said . “ Test results , where grinding intervals are more than doubled compared to standard products in automated conditions , really show how Autobit improves productivity .” The 4 in Autobit is available from stock today with more diameters arriving soon .
Also in focus was its next generation drill bit for rotary drilling , the Charger™ RR450 which it says can achieve up to a 90 % increase in bit life compared to other premium sealed bearing bits . “ The Charger™ RR450 rotary drill bit is Sandvik ’ s most durable to date . It is designed to maximise customers ’ drilling uptime , increase penetration rate and improve safety , thanks to fewer bit changes and reduced operator interactions . The new bit features Sandvik ’ s most powerful carbide range , PowerCarbide™ , as well as new cone steel protection , computer optimised cutting structures and the patented Charger™ sealed journal bearing system .” Testing shows that bit life can be increased by up to 90 % while maintaining the same high penetration rates .
“ Charger™ RR450 is truly a leap forward for our rotary bit offering ,” said Carsten Mijic , Product Manager for Rotary Bits at Sandvik Mining and Rock Solutions . “ We can now offer our customers nearly double the bit life compared to other premium sealed bearing bits . This can translate into hundreds of thousands of dollars saved , while at the same time reducing the need for operator interactions with the bit and drill deck .”
The company says a key reason for the improved bit life of Charger™ RR450 is the
inclusion of the PowerCarbide™ SH75 grade , part of Sandvik ’ s most advanced cemented carbide range . The self-hardening carbide grade can improve bit life by up to 50 % in abrasive rock conditions .
“ Earlier this year , we introduced the PowerCarbide™ SH75 grade to our rotary drill bit offering with the launch of the Sandvik RR240 air bearing bit range ,” said Mijic . “ It performs incredibly well , and we are pleased to be able to now include it in our ultra-premium sealed bearing bit offering . It is state-of-the art in its qualities , and very well suited for many of our customers ’ challenges .”
The new Charger™ RR450 bit is available today in sizes ranging from 9 to 12 1 / 4 in . Additional sizes and types will become available in the near future .
Finally , Sandvik introduced an entirely new top hammer drill bits range for the production drilling and quarrying markets . Sandvik ’ s Heavy Duty bits it says will help customers increase productivity and improve sustainability through longer grinding intervals and extended service life .
“ The new Heavy Duty drill bits are made to last . Depending on rock conditions , top hammer customers can expect up to twice the service life compared to standard bits , as well as lower cost per meter and , ultimately , lower total drilling cost . The all-new design also helps improve safety and sustainability .”
“ With our Heavy Duty drill bits , we ’ ve worked hard to find the optimal design and carbide grades to deliver as much customer value as possible , both with regard to productivity and also sustainability ,” said Fredrik Björk , Product Manager for Top Hammer Surface at Sandvik Mining and Rock Solutions .
Once again , for its Heavy Duty bits , Sandvik has added PowerCarbide™ technology , in this case self-hardening carbide grade SH70 . By itself , SH70 grade it says can provide more than 50 % longer service life , depending on rock conditions , and combined with the all-new design of the Heavy Duty bits , Sandvik presents a product that is “ tougher than ever .” Longer service life also “ creates clear safety and sustainability advantages , including less handling and reduced injury risk , but also reduced manufacturing carbon footprint .” Sandvik has its own carbide recycling program , where used carbide inserts can be recycled to increase circularity in the process .
“ Including PowerCarbide™ SH70 in these new drill bits can help our customers achieve much greater drilling results ,” said Thomas Blomfeldt , Product Manager for Top Hammer at Sandvik
12 International Mining | NOVEMBER / DECEMBER 2021