CONTINUOUS CUTTING
further haulage functionality that will allow the MC51 to load a 30-40 t mine truck , according to Styles .
“ We also have the ability to load directly onto a conveyor because of the smaller size of chips generated by the cutters ( compared with drill and blast ), but you have to look at what the right haulage mechanism for the application is ,” he said . “ It has to be flexible enough to keep up with the machine otherwise you lose the ‘ continuous ’ element of the process .”
The required flexibility of the haulage component is likely to become apparent when the company gets into full flow at Garson .
The trial – lined up as part of the mechanical cutting demonstration within the CMIC ( Canada Mining Innovation Council ) Continuous Underground Mining project – will see the machine carry out 400 m of development at the mine over a 9-12 month period . The aim is to access the McConnell orebody , as well as provide a primary case study for CMIC members and the wider industry to learn from .
Komatsu and Vale have worked extensively on examining the rock properties the machine is likely to encounter at Garson – “ they provided information ahead of time on their typical rock properties in both the ore ( with the nickel ), as well as the waste rock , which is generally a bit harder than the ore ,” Styles said – but the real learnings will be made now the machine is advancing past the blast-damaged rock at the operation .
“ The goal is to work through the project as a partnership on further developing that model / relationship between what performance looks like compared with the rock properties ,” he said . “ There will be a lot of learning and validation going on in the next 9-12 months .
“ This will allow us to determine where this type of technology is best suited in the future : both at applications within Vale and other places . It ’ s all about where mechanical cutting can excel .”
Vale , itself , has previously stated it plans to demonstrate the ability to cut rock in excess of 250 MPa ; cut at a commercial rate of more than 3.5 m / shift ; quantify the cost per metre of operation and start to look at the potential comparison with conventional drill and blast development ; assess the health , safety and environmental suitability of the mechanical rock excavation ( MRE ) process ; and gain insight into the potential of an optimised MRE process .
When asked what impact continuous cutting technology could have on the company ' s project pipeline , if proven economically and technically successful , Andy Charsley , Principal Mining Engineer , Vale Base Metals , had this to say : “ If continuous cutting technology can be done at an advance rate and cost structure that is comparable or better than conventional drill and blast , this will improve the feasibility of some future projects . Faster advance rates will allow access to orebodies sooner while less damage to the rock mass will improve tunnel conditions , especially in difficult ground . These factors will improve both the safety and economics of future projects .”
As it stands , Komatsu was able to cut through the 180-200 MPa UCS rock it encountered at Cadia , and Styles is confident it will be able to cope with any rock variability the Canadian Shield can throw at it .
“ The way the MC51 with the DynaCut technology works means we can break rock with a range of material hardness , from 50-100 MPa UCS to greater than 200 MPa ,” he said . “ Even if the rock changes properties while we are cutting it , we can still extract it with the same mechanism on the machine , with minor parameter changes to the software .
“ Our machine is quite flexible in terms of the type of material it can cut .”
This software – and the on-board cameras – will help the company push the machine ’ s lineof-sight operating credentials .
“ We ’ d like to , in the future , bring people further and further away from the cutting face ,” Styles said . “ With cameras on the machine , we should be able to demonstrate , in the next 12 months , some type of ‘ around the corner ’ mining where the operator is not in the line of sight but
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