UG LOAD AND HAUL sold over 40 units in South Africa since its introduction in 2008 but the mining downturn has hit hard in South Africa lowering the number of ST7 LPs being delivered today . The Atlas Copco Extra Low Profile ( XLP ) units were tested in South Africa and after some initial issues with the Tier 3 rated diesel engines they met all the KPIs . “ The trial of the equipment confirmed that it is practically possible to achieve safe XLP mining operations in the steeper reef dip environment with track mounted XLP units with good productivity levels . Before the drop in platinum price several mining companies showed great interest in the XLP units .”
On rebuilds and service , Atlas Copco offers midlife services in three levels to help customers get more out of their existing machines by extending the lifetime of the equipment : n Midlife BASIC - Main components replaced with components of the same specification to increase the lifetime of the machine including the evolution of safety features . n Midlife PLUS - Machine upgraded to latest specification and available options capturing the evolution of productivity , reliability and operator comfort . n Midlife TECH + - Machine is upgraded with the latest monitoring technology solutions to increase productivity . The Atlas Copco midlife value offering provides customers with updated machine documentation ; warranty as for brand new machines ; bridge unit solutions to ensure uptime ; and financing solutions .
On other technologies , the Kiruna AC truck ( now the Atlas Copco EMT-35 and EMT-50 ) is today in operation at two sites in Canada ( Vale ’ s Coleman and Creighton nickel operations ) where the company continues to support its customers and is about to deliver another EMT-50 truck . The interest in electric trucks is high but the large initial investment makes it a difficult decision in these challenging times but already after three years it can start to pay off , says the company . In a presentation from the International Conference on Renewable Energies and Power Quality in 2014 from the Department of Mining , Metallurgical and Materials Engineering at Université Laval and Atlas Copco , the authors state : “ The most important advantage of these trucks is their high overload capacity and very good gradeability . On a 14 % ramp the speed for the electric truck running up is almost double when compared to a similar diesel unit . Due to this , their production rate is on average 20 % higher and a smaller truck fleet is needed to meet certain production targets . Electric trucks also have a favourable ratio between useful load and empty vehicle weight ( 1.06 and 1.1 for EMT- 35 and EMT-50 respectively ), similar to dieselpowered trucks . It is estimated that for the same ramp haulage system and production rate , electric trucks will use only 24 % of the energy per tonne hauled as compared to a diesel fleet . This means that application of electric trucks can generate economies stemming not only from a lower ventilation cost , but also from substantially smaller energy cost .”
Vale ’ s Coleman mine near Sudbury has 18 years of experience with electric trucks . It now operates a fleet of five 50 t vehicles running on the longest trolley line ever built ( cumulative length of 6,200 m ). “ Trolley-powered trucks constitute a solution that has not yet received adequate recognition it merits . The example of the Coleman mine in Canada , where Kiruna trucks have been successfully used for the last 18 years and whose performance is fully satisfactory to mine management proves that full commitment of both the mine and the OEM makes this concept a winning solution . Electric trolley-powered trucks definitely merit more consideration in the cases of future and existing mines with truck haulage over long ramps . Again , this solution is not a universal one , but it has the potential to be beneficial in some particular applications . Any potential application should be thoroughly studied and analysed to maximise chances for a success .”
Finally the Haggloäder continuous loaders have been used in tunnelling mainly to date but Atlas Copco believes strongly in the usage of this type of equipment in mining . “ We are working with several mining companies to explore this opportunity and to explain the benefits of a continuous system . The launch of the LOT ( Loading Optimisation Tool ) has rendered a lot of interest and opened up the eyes for the use of Häggloader instead of traditional loaders . Currently we have sold Haggloäders into mining in Canada and Indonesia and also performed successful trials in South Africa ’ s platinum mines to replace traditional pneumatic rail bound equipment . Here it proved to increase rates ( cubic metres per hour ) by 40 %.”
Caterpillar refocuses for the future
The big change at Caterpillar in terms of underground load and haul machines has of course been the moving of production from
Burnie , Tasmania ( with some production in the past near Sao Paulo , Brazil ) to the Port of Rayong , Thailand , with some machines now being made in Houston , Pennsylvania , and Burnie remaining as a major engineering centre . The range still covers LHDs from the R1300G ( 6.8 t payload ), R1600H ( 10.2 t ), R1700G ( 14 t ), R2900G ( 17.2 t ) and R3000H , the newest and largest LHD with 20 t payload . The truck range includes the AD30 ( 30 t ), AD45B ( 45 t ) and AD60 ( 60 t ). Compared to competitors , Caterpillar as it does with its surface equipment emphasises that these are largely 100 % Caterpillar products including engines and major components , backed up by the company ’ s unique dealer structure and parts supply network .
Robert Droogleever Fortuyn , General Manager , Caterpillar Underground Mining told IM : “ By restructuring and implementing Caterpillar ’ s new facilities , we have been able to focus on quality control through use of the Caterpillar Production System ( CPS ). Caterpillar manufacturing processes are unmatched . Restructuring at a lowvolume part of the cycle is much easier than at other times .” See this month ’ s High Profile article for more comments on the market from Robert Droogleever Fortuyn
In terms of automation , Freeport and Codelco remain the key strategic partners for ongoing Command for Underground development and implementation . A good case study is Freeport ’ s Grasberg operation in Indonesia – Drooglever comments : “ We have operators on the surface working the underground loaders . The next stage is auto-digging with loaders and then , after that , truly autonomous loaders with no operator input … the loaders are our current target , then truck automation will follow . Previously our focus was on remote – in this case line-of-sight – working ; now we are conducting fully remote with the operators distanced from the actual operation but connected by cameras and sensors . Next we will move towards installing sensor nodes and the diggers will drive themselves without any operator involvement . We ’ re actually pretty close to that now .”
The still fairly new R3000H LHD already has a number of references ( see table ), including with different automation levels . Global contractor Byrnecut as an example is using an RH3000H equipped with Command for Underground at Sandfire ’ s DeGrussa mine in Western Australia . The machine and the system have been working
JUNE 2016 | International Mining