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Productive open pits John Chadwick looks at simulators, lowboys and other technologies to overcome today’s equipment constraints, as well as looking at innovations in ‘the iron’ and the great potential of rebuilt machines
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urface mining equipment simulators have become popular in recent years. Much like aircraft simulators used to train and update pilots, such units have revolutionized mines’ approach to recruitment, training and productivity. These facilities allow mining companies and contractors to train and assess operators using a safe, educational, production enhancing, easy to use and low-cost system. Companies are increasing their focus on higher productivity and efficiencies as well as improved safety for their employees and simulators have a very important role to play. Furthermore, in these times of high fuel prices and the tyre problem that is likely to be with us for another year or so (IM, September 05, pp. 41-43), simulators provide much of the operator training that is needed, while saving these expensive and scarce consumables. Also while there may be long lead times for new machines, simulators save productive machines from being taken out of the operating line. One simulator manufacturer is Western Australian-based Immersive Technologies. Immersive has just entered into a landmark licensing agreement with the world’s largest manufacturer of surface mining equipment. The exclusive agreement with Caterpillar allows Immersive Technologies to promote its Advanced Equipment (AE) simulator brand in conjunction with the globally renowned Cat trademark. A new mark, identifying licensed Caterpillar technology, is now being used by Immersive. This is the first application of the mark intended to authenticate such products.
This continues a powerful association between Immersive Technologies and Caterpillar. After an extensive evaluation of available simulator technology, and the growing impact of training simulators in mining, Caterpillar last year announced it would exclusively recommend, and provide proprietary machine technical information for, Immersive Technologies’ AE simulators. Immersive has more than 65 AE simulators deployed in 14 countries around the world and has for more than eight years been a leader in the development of mining equipment training simulators. Operator stations and exact working conditions have been created for more than 55 different machine types, and Immersive software has been used to replicate site surrounds at nearly 70 mine sites. Immersive has sales and marketing agreements with some of the world’s leading mining OEMs. This is important to ensure the extensive range of AE simulators achieve the necessary levels of realism and accuracy through the use of licensed proprietary data and machine technical information from the OEM. Immersive Technologies CEO Peter Salfinger said, “the Caterpillar branding approval was a significant milestone for the company. It signifies further high-level acknowledgement of the uniqueness of our market offering. It also reflects an acceptance by Caterpillar that our simulators have become an integral part of the training programmes of, and are produc-
ing significant benefits for, their customers – the world’s major mining companies and contractors.” South African simulator manufacturer 5DT lists the benefits of simulators as: ◆ Reduced loss of production during training ◆ Shorter operator training periods ◆ Enhanced skills development ◆ Improved of best practices ◆ Increase in annual average production per machine ◆ Reduced machine damage and increased safety awareness ◆ Increased motivation
The hole story Unto Ahtola, President, Tamrock Surface recently explained to IM that Tamrock Surface has trebled its turnover in the past 10 years. At the beginning of September, Tamrock rolled out a prototype for the new Pantera line of surface drills. This unit is to be something of a test bed to introduce to the market those new technologies that Tamrock Surface expects to see soon: ◆ The new generation will bring realtime information on machine operations and conditions – available within a year ◆ Different operators will have their own settings, those allowing them to ‘dial’ back in for their preferred operating parameters and allowing them to work at their best ◆ Improved drilling accuracy through greater use of GPS ◆ Better rock sensing by the drill
Last month, IM noted how the independent, four-wheel electric drive of the LeTourneau wheel loader line improves traction and minimizes tyre scrubbing and wheel slippage, which in turn increases tyre life. LeTourneau reports that its loaders "generally deliver twice the tyre life of their mechanical drive counterparts." Just as important is the fact that electric drive involves running engines at an efficient, constant RPM, which can reduce fuel cost by $10-30/hour depending on the capacity of the machine. Fuel efficiency also means reduced emissions and other environmental advantages. October 2005 International Mining 7
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◆ More remote support from Tamrock engineers. Specific focuses of the prototype include safety and serviceability and operator comfort. The new electrical control system features self-diagnostics and the rig has a generally higher level of data collection. This rig will fully integrate the Tamrock San Remo system that provides remote access to machine health and performance. Contracts for maintenance and repair are becoming more popular. A recent example is the services Tamrock is providing to 12 Pantera 1500 rigs used by Gold Fields at the Tarkwa gold mine in Ghana. The mine has three such contracts in place – one with Liebherr for the shovels, one with Caterpillar for the trucks and the drill contract with Tamrock. Tarkwa comprises multiple open pits, so the use of lowboy trailers to transport the Panteras around the operations is important to increasing utilization and reducing wear. Furthermore, as part of Tamrock’s contract, drill consumables are delivered to the machines in the pits, to further maximize utilization. Mean Time Between Failures and Mean Time to Repair are important aspects of maintenance contracts. Monthly performance reviews are also very important. In this instance, there is a full-time preventative maintenance team and a totally separate team to carry out in-pit maintenance. The mine is ISO 14001 certified, requiring great care to be taken in maintenance and in-field servicing. The Tamrock support at Tarkwa has been a great success, attributable to the right people running the contract. These people understand the goals and ideals of the mining company, and are involved in the local community. Being part of the local community is very important. The one-to-one, where necessary, operator training has helped in that regard.
Supply constraints IM asked leading suppliers about current long lead times for certain machines and consumables? Liebherr says it “has been working closely with tyre manufacturers
A rebuilt scraper leaves Hoss. The customer chose this alternative because delivery lead-time for new a 657E is approximately 18 months.
to adapt longer lasting tyres to Liebherr trucks. With the advent of the 63-in tyre size, the mines have a number of tyres scheduled. If the tyre life can be increased by 15%, that is equivalent to getting 15% more tyres than the mines had originally scheduled.” Bucyrus points out that the decisionmaking process for purchasing surface mining equipment and ancillaries is quite often a complex, multifaceted endeavour. One of the many methods it employs “to assist potential customers in making informed purchasing decisions is to provide precise data in its quotes to illustrate the overall operating costs of its machines thereby allowing mines to accurately calculate ROI. For example, proposals include detailed analysis forecasting parts consumption and cost throughout the life of the machine. “Forecasting also plays a crucial role in addressing the issue of lead-time for parts and new equipment. Bucyrus takes a proactive approach by anticipating customer needs on a machine-by-machine basis. At the onset of the steel crunch, Bucyrus contacted 100% of its end users and based on the status of their machine(s) forecasted when and what parts or equipment would be needed during the next three years. Numerous variables such as analysis of maintenance history, operating hours and a machine’s importance on the job aid in determining a mine’s future requirements. “Upgrading or recommissioning existing units allows mining companies to bypass longer than usual lead-times and expand their operations to benefit from the strong commodity market. The influencing force of the tyre crisis has made substitute capacity a key element in today’s market. Bucyrus continues to encourage mining operations to take advantage of idle draglines available as an alternative to truck and shovel operations
when the application is appropriate.” Bucyrus says: “The future needs of surface mining centre around more automation, standardization and consolidation on machines and in mining operations. From GPS to integrated monitoring systems, Bucyrus offers a variety of technologies to help meet these needs. [The] powerful AccessDirect system has many features that greatly enhance machine management capabilities. It provides real-time worldwide access to machine information for machine status tracking and fault resolution. This affords mine maintenance personnel, OEM service technicians or factory engineers the ability to monitor a machine and make adjustments from remote locations. “Bucyrus consistently works in a dedicated and extensive manner to increase the performance of its installed base through enhancements and upgrades. An upgrade such as Bucyrus’ patented Automated Crowd Rope Take-up System for Bucyrus brand shovels creates a safer and more efficient way to tighten the crowd rope. Bucyrus also offers a variety of upgrades for draglines and blasthole drills. The partnership Bucyrus formed with Siemens resulted in the creation of Direct Drive for Draglines (D3), which is available as an upgrade or on new draglines. This technology is applied to the hoist and drag system to improve overall machine productivity while reducing maintenance and operational cost. A featured electrical upgrade for drills includes the PLC 5 system. This system replaces the obsolete PLC 2 system providing increased functionality and compatibility with other systems.” Liebherr notes: “Many factors, such as mine life, infrastructure and loading equipment enter into the equation regarding appropriate size of equipment. While there will likely be an increase in opportunities for smaller equipment at marginal mine sites, larger equipment will be utilized where feasible, since, among other benefits, it has the advantage of partially offsetting the worldwide shortage in trained labour to operate and service mining machines. Is the drive for bigger loading tools and trucks a thing of the past? Should mines focus rather on GPS, dispatch systems and other ways of raising efficiency and reducing costs? Liebherr: “In many situations utilization of larger equipment provides increased production and resulting cost per tonne reductions that are far greater than other innovations can offer. Accordingly development of larger tools will continue especially with regard to lowering the operating cost and increasing the productivity of existing sites.” Bucyrus: “As it relates to surface mining, the debate on whether bigger really October 2005 International Mining 9
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is better must be considered carefully. The layout of a mine, the commodity being extracted, the life of the mine and the investment capital available for purchasing equipment are all factors used to determine if it is logical to purchase such machines. Loading equipment capable of large payloads coupled with technological advancements has historically maximized productivity, allowing mines to achieve economies of scale. Therefore, the drive for bigger loading tools and trucks will most likely continue. As technology advances the use of ever-larger machines becomes more feasible. The shortage of skilled labour in many regions is also contributing to the push toward bigger machines since less manpower is required to operate large equipment.
Highlight advances in some of the many challenges for surface mining equipment these days, like reducing noise levels, operator comfort, or prolonged wear life for components. “Noise reduction has been a concern for the last 20 years. It is becoming more important all the time. Liebherr has made notable advancements within this area regarding both truck and excavator operation, particularly at one mine location in Australia where stringent noise reduction standards were specified. Modifications to equipment to achieve higher reductions come at a price, not in machine performance, but in dollar investment in labour and componentry to achieve the reduction. “Operator comfort is getting more consideration, regarding truck ride quality
Whether Buying a Truck or a Fleet...
Buy HOSS! There is a difference when you buy from Hoss™. Our 30-acre rebuild facility, 26 Service Bays, experienced Mechanics and Welders, knowledgeable Sales Force, massive equipment inventory, leading-edge machine demo technology and an unwavering commitment to excellence combine to save you time and money on the acquisition of high-quality, reliable surface mining and heavy construction machinery. The Hoss Custom Rebuild program delivers outstanding value. These exceptional machines provide 100% the performance of a like-model new machine for about 60% of the cost. Each machine delivers a lower operating cost than a new machine and is sold with a limited 1-year, 2000-hour Powertrain Warranty. Visit www.hossequipment.com to view our all-new Web site. Find more of what you need... more selection in one physical location, more photos from more angles and more detailed information (more answers) about each machine than are typically shown on competing Web sites. To experience the Hoss Difference, contact Hoss Sales by telephone at 1 244 or by e-mail at
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(less vibration) – which is a very important factor. It has been shown that truck operators have a tolerance for a certain level of shock and vibration. It appears that as the equipment ride quality is improved, the operator traverses the rough spots on a haul road at a higher speed but still stays below his tolerance level. As a result, the truck has to be able to withstand operation at higher speeds across these rough portions of roads. Improving operator comfort interestingly enough often results in harsher operation of equipment. “The wear life of components is an important part of equipment productivity and lower operating cost. Mines continue to expect increases in the service life of components as well as the overall life of the machine structures. Many components still have not developed to that level of service life however all have expanded service lives due to continued research and product development programmes.” Bucyrus: “Using cost-effective methods and technologies, Bucyrus is intensely focused on providing mines with the resources necessary to increase production, reliability and availability. These resources are not just limited to supplying quality parts and equipment, but also include services that meet and exceed the expectations of customers. The advisory role Bucyrus engages in with its customers consists of applying the vast expertise the company has to offer in order to provide value-added aftermarket support and service. This can include such efforts as helping mine maintenance management with effective shutdowns and making recommendations on how to increase performance. “The Maintenance and Repair Contracts (MARC) offered by Bucyrus help mines manage their surface mining equipment to achieve maximum reliability and uptime. Each MARC is tailored to meet the specific needs of each customer providing much more than a basic maintenance and repair contract. Bucyrus can provide a comprehensive programme to cover all maintenance and operating aspects of a customer’s machine."
Reborn to run Faced with long lead-times, there is a viable low-risk alternative to buying new machines – to buy a totally rebuilt machine from an experienced and respected rebuilder such as Hoss Equipment. The Hoss Custom Rebuild (HCR) programme represents years of refinement in the ‘headwork’ and ‘physical work’ that goes into the successful completion of a ‘total rebuild project’. Caterpillar and others design their heavy machines to be rebuilt. Second and third ‘work lives’ are possible on big
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Surface mining machines that have been well maintained and then have been processed through a reputable complete rebuild programme. Hoss points out that the main barrier is perceptions of upper limits of number of operating hours, after which machines are worn out and forevermore unreliable. Ron Richardson, Hoss Director of Marketing, says, “most perceptions are very hard to change once formed. This perception, however, is simply not true. “While it is true that components and parts wear out and the machine’s ‘softer’ structures get dented in day-to-day operations, the core - the foundation upon which the machine is built - is designed to ‘keep on going’. To make this possible, stringent rebuild guidelines have been developed by Caterpillar to shepherd Dealers and other rebuilders of Caterpillar equipment in every step of the process. “There are two key benefits to mining operations that need to be considered when deciding to buy - or not buy - a completely rebuilt machine. The first is cost. Expertly rebuilt and updated, HCR machines deliver 100% of the performance and reliability of a new like-model machine for about 60% of the cost of a new machine. This represents considerable savings to companies and provides a machine that delivers ‘new’ machine power and reliability at a lower operating cost than when originally purchased new.
“The second key consideration, especially in times like these, is ‘availability’. Delivery of a completely rebuilt machine that is covered by a one-year, 2,000-hour limited powertrain warranty can be as close as 45-days (on the short side) to 90days (on the long side) from the date the core is selected.” In the HCR programme, cores (used machines) are sourced from around the world and shipped to Irving, Texas. Once received, they are completely disassembled, expertly rebuilt, reassembled, sand blasted, primed, repainted, tested and then placed into inventory. Hoss has invested millions over time to develop an industry-leading infrastructure that includes 26 service bays, well-trained mechanics and welders and a state-of-theart sandblast/paint facility. Additional millions of dollars have been invested in original Caterpillar parts and Caterpillar Dealer support. Selecting the ‘right’ core is one of the most crucial steps in the labour-intensive rebuild process. Each machine has to be inspected, acquired, transported, torn down, reconditioned, reassembled, tested, inventoried, tested again prior to shipment, and then partially disassembled for shipment and delivered to its new owner - covered by a strong warranty - at a cost that still represents a significant saving to the owner versus purchasing a new machine of the same design. To meet this challenge, Hoss
has in-depth knowledge and expertise in the machine inspection and buying process. In general, Hoss rebuilds Caterpillar mining machines with genuine Caterpillar new, rebuilt or exchange components, a completely new undercarriage or a new set of tyres. Electrical systems are checked and replaced as needed. Hydraulic systems are restored to original performance. All hoses, belts, seals, gaskets, bearings, knobs, wiring, switches, and gauges will be replaced with new parts. Worn linkage pins and shaft bearings are replaced. Cabs are detailed; seating is recovered or replaced as required. All sheet metal is repaired or replaced as needed. To provide maximum value to HCR customers, all powertrains are rebuilt by one of Hoss’ selected Caterpillar Dealers under the Certified Power Train programme. Engines, fuel systems, transmissions, torque converters, differentials, final drives, and radiators are disassembled, inspected, and reconditioned with new or qualified parts. Each component is thoroughly bench tested before reinstallation. Engine Electronic Control Modules are replaced and the most current engine operating software is installed. Reassembled engines and transmissions are Dynamometer-tested prior to return to Hoss. These tests are specified to detect possible leaks (both fluid and air), monitor lubrication, fuel and boost pressures and to evaluate overall engine performance.
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Bauxite in Guinea (here) and coal in India are just two of the area’s of success of the Wirtgen surface miners.
As an example, Hoss is currently rebuilding two 1980 CAT 657B Coal Scrapers for a large global company with US operations in Alabama. The last 657Bs were manufactured in 1983. These rebuilt scrapers will be delivered to the customer
with all of the technological and engineering updates introduced since their original 1980 manufacturing date and more (including conversion to 651Bs by removing the rear engines, transmissions and differentials). While these machines
cannot be upgraded to the current production models, the 657E or 651E, they can be modernized. Each machine receives a Tier 2, Stage II compliant 3456E Air-to-Air aftercooled engine using a Caterpillar-sanctioned process. This engine produces the same power and torque as the original engine. It delivers better throttle response and consumes less fuel for reduced operating costs. The engine is also lighter and this weight saving will result in better overall steering. A next generation J1939 MurphyLink PowerView System is also being installed in each converted 651B. The PowerView System is an advanced instrument and gauge solution for SAE J1939 CANBUS engines. It comprises the PowerView Digital Display and the MLink PowerView Analog Gages. This multifunctional tool enables equipment operators to view many different engine or transmission parameters and service codes. Diagnostic capabilities include fault codes with text translation for the most common fault conditions.
Performance testing Following re-assembly, Hoss machines leave the shop and undergo rigorous testing. Complete tests are made for: ◆ Turbocharger boost at full load and stall speed ◆ Throttle response and engine rpm check at stall speed ◆ Transmission and steering clutch pressures ◆ Hydraulic and pilot relief valve pressures, and cycle times ◆ Cooling system performance under varying engine loads ◆ Overall machine performance and leaks.
A Bucyrus boom? Bucyrus is certainly optimistic about the market, announcing in August that it is proceeding with the expansion of its manufacturing operations at its South Milwaukee facilities. The company said that “as a result of the strong commodity market, the demand for Bucyrus’ equipment has increased dramatically and Bucyrus is continuing to expand its capacity to meet that demand.” The initial phase will include the construction of a new Rawson Avenue facility for welding and machining large electric shovel components. It will also provide capacity for welding and machining large walking dragline components should they be required to meet market demand. “This initial expansion will effectively increase our capacity to manufacture large electric mining shovels by 50%,” stated Tim Sullivan, President and CEO. 12 International Mining October 2005
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Surface mining “Based on our assessment of current and future market demand for our equipment, in particular our electric mining shovels, we believe that now is the time to move forward with additional manufacturing capability” One of the latest Bucyrus shovel sales was to a major coal producer in the USA. A 495HR (Hard Rock) high performance electric rope shovel to support production targets joins a fleet of Bucyrus brand machines already operated by the company. Bucyrus says the 495 “has a proven history of outstanding productivity and incorporates new and innovative technologies which enhance its capabilities.” It uses the Siemens AC - IGBT electric drive system. The AC system eliminates brushes, fuses and RPC components that are high maintenance items on DC drive machines. A fully modularized electrical room ships directly to the field to facilitate the erection process. 495HR shovels carry the new SuperCab that sets high standards for operator visibility, comfort and safety. In addition, the machinery house includes an additional workroom under the operator’s cab and roof hatches, which allows ready access to all components on board the shovel. Reliability and ease of maintenance are key ingredients of the design. A few of the numerous features include a third rail swing system (which uses larger, wider, flangeless lower rollers) and lowered swing planetaries to provide for improved maintainability and ease of maintenance. To further productivity, this 495 shovel will be equipped with AccessDirect remote machine diagnostics. AccessDirect allows for direct access to a machine’s electrical system by a Bucyrus engineer from anywhere in the world. Machines in remote locations are as close as a modem or Internet connection. AccessDirect means that in many cases adjustments or repairs can be made without the need to attend the machine. For machines in remote locations that would otherwise require hours and sometimes days to reach, this can be critical in maintaining a machine’s productivity. On this 495, AccessDirect will be enhanced by AccuLoad
A low inertia boom design is an exclusive feature of Bucyrus’ rope crowd machines and allows for greater operator control and visibility when swinging. In addition, design enhancements in all structural areas and increased power in key digging motions, allow the 495 High Performance shovel to provide payload ratings at the top of its class. 14 International Mining October 2005
and MIDAS. AccuLoad is setting standards for precise weighing of each individual dipper load. MIDAS provides production tracking and maintains ongoing detailed records of the various machine motions and activities. The resulting digital history allows managers to track and set benchmarks for improving productivity. When commissioned later this year, the new 495 will carry a 63 m3 dipper. As part of the commissioning process, Bucyrus will provide turnkey erection and an extensive training program to support a quick ramp-up to full productivity.
Carrying the burden The commentary on Tarkwa above noted the use of lowboys. These are attracting interest around the world. BHP Billiton recently ordered two TowHaul lowboys for its Chilean mines, Escondida and Cerro Colorado. TowHaul says lowboy/tow truck combinations offer cost saving mobility for tracked dozers, blasthole drills, shovels (up to 1,200 t operating weight) and disabled haul trucks. They are ideally suited for loads of 100 t and greater, and are able to use a towing unit as small as 75 t. Providing transport for equipment within the operation area, speeds machine moves and saves wear on crawlers and tyres wear. One unit, a TowHaul lowboy, model RGS-LP-54-21, 250 t capacity is 16.5 m long and 6.4 m wide and was acquired for Minera Escondida, where a similar lowboy has been in use since 1999. Therefore, this new unit confirms the preference for this brand’s quality. The second unit for Cerro Colorado is a 136-t capacity model RGS-LPM-150-42-20, 12.8 m long
and 6 m wide. It is expected that two more lowboys will be delivered to this customer early in 2006.
Continuous mining Wirtgen’s surface miners are making steady inroads into the market, most notably in salt, limestone and coal extraction. In the latter case Wirtgen machines mine 40 Mt/y of Indian coal. There have also been interesting developments in bauxite in Guinea. In the Tsentralnaya orebody of the Debele mine ore pillars had been left in the vicinity of a generator substation and along a public road and a rail line. No blasting was allowed here but the reserve of these pillars was estimated to be around 89,000 t. Further locations with similar conditions had been identified. In 2000, Kompanyia Boksity Kindii purchased a Wirtgen 2100 SM to extract these sections without blasting. Over nine and a half months, i.e. some 3,000 working hours, this machine mined 300,000 t of bauxite and 25,000 t of overburden. In 2001, CGG bought a 2200 SM Wirtgen. Working in the Tsentralnaya orebody, in just three months (some 900 working hours), this mined 95,000 t of bauxite and 20,000 t of overburden. In both cases the Wirtgen units operated on narrow faces with lengths of 100 to 160 m and widths ranging from 35 to 55 m. Highway trucks with an average capacity of 16 t were loaded with the mined material. Tested rock samples showed a compressive strength of 30 to 125 MPa. The compressive strength to tensile strength ratio ranged from 5 to 7. This indicated a tough material.
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Depending on the hardness of the rock, cutting performances ranged from 140 to 550 t/h, averaging around 250 t/h. What was important was that different rock hardnesses could be cut without interrupting the mining process. By March 2003 nearly 1 Mt of bauxite ore from the reserve’s abandoned zones, where drill and blast was not allowed, had been extracted by means of Wirtgen SMs. The clean removal of bauxite and the production of small particle sizes, along with the elimination of the crushing process, convinced the bauxite mine operators of the strengths of the Wirtgen Surface Mining technology. Apart from mining abandoned areas where blasting is prohibited, the technology was also considered for general use at the Frija ore deposit, which, up to 2003, had been mined by conventional drilling and blast. However the very complex deposit structure made it very difficult to achieve the required ROM quality. The Frija ore deposit consists of five ore zones; each of them has 3 to 7 seams, with thicknesses ranging from 2 to 12 m. The ore seams contain substantial inclusions of low-grade bauxite (below 37%). Therefore ore has to be mined from several pits to achieve the required quality. The 2200 SM was shifted to this deposit in April 2003 and is now used for the selective bauxite mining in this difficult geology. The miner dumps cut material on the ground to build up a mine stockpile. The material is later loaded on demand by wheel loaders into 100-t capacity trucks. In 2003, of the total production of 2,308,000 t, 414,000 t were mined selectively. The average production per machine motor hour was 180 t. When planning an expansion the mine decided to purchase a 2500 SM. In addition to its selective mining ability, the mine was able to eliminate the expansion of the crushing plant since the particle size produced by the SM eliminates primary crushing. The 2500 SM was commissioned in July 2004 and during commissioning achieved an average 500 t/h on average. Taking truck change and maneuvering times into
Myth The GPS satellites could be shut down at any time, leaving mines with obsolete GPS systems.
Fact GPS is funded and controlled by the US Department of Defense, which has a commitment to keep GPS operational
GPS has costly subscription fees.
GPS is paid for and supported by US taxes, so there are no subscription fees.
Dependable GPS systems for mines are years away.
Robust GPS systems are now available that provide up to 2-m accuracy for mobile equipment tracking, and sub-meter accuracy for shovel and drill positioning.
High-precision GPS systems require a high-band width radio channel.
High-precision GPS systems can virtually unlimited numbers of trucks, shovels, drills, dozers, etc., minewide, on a 9,600 b/s radio channel.
GPS isn’t practical for deep pit mines.
Many deep pit mines, where the view to the horizon is partially blocked, have adequate coverage when GPS is augmented with the Russian GLONASS, which is similar in scope to GPS and provides up to 24 additional satellites when fully deployed.
GLONASS is unreliable.
The Russian government has gone on record with a long-term commitment to support GLONASS.
Source: Modular Mining
account, the real average is 360 t/h. The Wirtgens in Guinea have shown this technology is an economic solution for: ◆ Mining bauxite without blasting ◆ Mining materials of varying hardness without interrupting the mining process ◆ Selective mining of different bauxite qualities ◆ Elimination of primary crushing.
Seeing safety Intec reports that, while used initially as a safety feature, on-board cameras can help cost-efficiency in several ways. An operator with sufficient visibility can direct the machinery more confidently and hit fill and dump points more accurately. With escalating tyre costs, there is great advantage in seeing and avoiding hazards before damage can occur. A wide-view camera can provide the operator with the necessary visibility to manoeuvre safely, with the added benefit
of seeing the ground immediately ahead or behind the tyres. Operator health and comfort are also addressed with cameras. Most heavy equipment requires the operator to twist, turn and stretch to see around the equipment before moving. A camera system brings these difficult views into the cab, where the operator can see them in normal sight lines. With the possible increase in productivity and reduction of downtime, camera systems are a small investment that can yield big rewards.
Fleet management GPS solutions for mobile equipment tracking, shovel and drill positioning, and more are used by a growing number of mines worldwide. But, Modular Mining reports, “as demand for GPS increases, so do the myths and misconceptions surrounding the technology:” IM
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