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  • 1.
    Galar, Diego
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Tormos, Bernardo
    Berges, Luis
    Podejmowanie decyzji eksploatacyjnych w oparciu o fuzje{ogonek} różnego typu danych2012In: Eksploatacja i niezawodnosc - Maintenance and Reliability, ISSN 1507-2711, Vol. 14, no 2, p. 135-144Article in journal (Refereed)
    Abstract [en]

    Over the last decade, system integration is applied more as it allows organizations to streamline business processes. A recent development in the asset engineering management is to leverage the investment already made in process control systems. This allows the operations, maintenance, and process control teams to monitor and determine new alarm level based on the physical condition data of the critical machines. Condition-based maintenance (CBM) is a maintenance philosophy based on this massive data collection, wherein equipment repair or replacement decisions depend on the current and projected future health of the equipment. Since, past research has been dominated by condition monitoring techniques for specific applications; the maintenance community lacks a generic CBM implementation method based on data mining of such vast amount of collected data. The methodology would be relevant across different domains. It is necessary to integrate Condition Monitoring (CM) data with management data from CMMS (Computer Maintenance Management Systems) which contains information, such as: component failures, failure information related data, servicing or repairs, and inventory control and so on. These systems are the core of traditional scheduled maintenance practices and rely on bulk observations from historical data to make modifications to regulated maintenance actions. The most obvious obstacle in the integration of CMMS, process and CM data is the disparate nature of the data types involved, and there have benn several attempts to remedy this problem. Although, there have been many recent efforts to collect and maintain large repositories of these types of data, there have been relatively few studies to identify the ways these to datasets could be related. This paper attempts to fulfill that need by proposing a combined data mining-based methodology for CBM considering CM data and Historical Maintenance Management data. It shows a system integration of physical and management data that also supports business intelligence and data mining where data sets can be combined in non-traditional ways.

  • 2.
    Galar, Diego
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Parida, Aditya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Berges, Luis
    University of Zaragoza.
    Use of vibration monitoring and analysis as KPIs in paper industry2011In: Proceedings of the 24th International Congress on Condition Monitoring and Diagnosis Engineering Management: COMADEM 2011 / [ed] Maneesh Singh; Raj B.K.N. Rao; J.P. Liyanage, COMADEM International, 2011, p. 135-147Conference paper (Refereed)
    Abstract [en]

    The use of automated systems for monitoring or surveillance of the condition of machinery for an industrial plant is becoming more common. Variables or indicators are transmitted to a database connected "on line" with such systems, allowing us to correctly track the condition parameters included in the PdM (Predictive Maintenance) Program. A practical example of an installation of 500 measuring points in a paper mill is presented in this paper. Paper mill plants show a wide variety of defects and conditions related to problems in rotating machinery bearings, gears, low speed operation, variable speed machine due to harsh conditions in the environment for elements of the installation and other adverse factors. Therefore, the vibration analyses are presented as physical indicators of the technical system for this type of machinery, on which the maintenance performance metrics are built. The article concludes presenting the "state of the art in data transmission to remote facilities engineering, for predictive diagnostic in order to detect potential problems in machinery which facilitate decisionmaking process in maintenance departments. These systems allow the rapid construction of the KPIs at different hierarchical levels. Therefore an approach to decision making based on the Maintenance methodology has been developed as a result of technological advances in the collection of physical data

  • 3.
    Ghosh, Rajib
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Danielsson, Markus
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Falksund, Hanna
    Luossavaara-Kiirunavaara Aktiebolag (LKAB), Malmberget.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessment of rock mass quality using drill monitoring technique of Hydraulic ITH drills2017In: International Journal of Mining and Mineral Engineering, ISSN 1754-890X, Vol. 8, no 3, p. 169-186Article in journal (Refereed)
    Abstract [en]

    A rock drilling system always responds to variations in the mechanical properties of the penetrated rock mass. Combining the drill response with a detailed understanding of the drill system has the potential to give a detailed and high-resolution characterisation of the penetrated rock mass along the borehole. This paper analyses 186 boreholes, drilled using a water powered in-the-hole (ITH) drilling technique considering drill parameters; penetration rate, rotation pressure, feed pressure and percussive pressure. In addition, it suggests, calculates and uses a parameter reflecting rock fracturing. Sixty-three of the holes were filmed with a borehole camera to reveal the geo-mechanical features. The results show that the responses from the drill monitoring system can distinguish between solid rock, fracture zones, cavities and damaged rock. The ability to extract this information directly from the drilling operation provides unique prior information and can be useful to adjust production planning before charging and blasting boreholes.

  • 4.
    Ghosh, Rajib
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Development of a geological model for chargeability assessment of borehole using drill monitoring technique2018In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 109, p. 9-18Article in journal (Refereed)
    Abstract [en]

    In the mining industry, the ability to charge and blast a production borehole is fundamental. However, if rock mass conditions are challenging, with cavities, fracture zones or even unstable boreholes, the charging crew may fail to insert the required amount of explosives, resulting in bad fragmentation and significant production disturbances in the downstream process. Prior detailed knowledge of the chargeability of each production fan or ring will improve both the planning and execution of the charging work in a mine. The paper describes a study using the drill monitoring technique to assess the chargeability of production boreholes. For the study, data were collected on four drill parameters, penetration rate, rotation pressure, feed pressure and percussive pressure, from 23 drill fans with a total of 186 boreholes. A parameter called fracturing was calculated based on penetration rate variability and rotation pressure variability. Sixty-three boreholes were filmed to establish different rock mass conditions: solid rock, cavities, fractured zones and cave-ins. Principal Component Analysis (PCA) was performed to model the relationship between drill monitoring data and the geological features. The developed model shows high potential by identifying charging problems directly from drill monitoring data, and has been verified and validated in a real charging operation in an operating mine.

  • 5.
    Ghosh, Rajib
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Monitoring of Drill System Behavior for Water-Powered in-the-hole (ITH) drilling2017In: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 7, no 7, article id 121Article in journal (Refereed)
    Abstract [en]

    A detailed understanding of the drilling system and the drilling control is required to correctly interpret rock mass conditions based on monitored drilling data. This paper analyses data from hydraulic in-the-hole (ITH) drills used in LKAB’s Malmberget mine in Sweden. Drill parameters, including penetration rate, percussive pressure, feed pressure, and rotation pressure, are monitored in underground production holes. Calculated parameters, penetration rate variability, rotation pressure variability, and fracturing are included in the analysis to improve the opportunity to predict rock mass conditions. Principal component analysis (PCA) is used to address non-linearity and variable interactions. The results show that the data contain pronounced hole length-dependent trends, both linear and step-wise linear, for most parameters. It is also suggested that monitoring can be an efficient way to optimize target values for drill parameters, as demonstrated for feed force. Finally, principal component analysis can be used to transfer a number of drill parameters into single components with a more straightforward geomechanical meaning

  • 6.
    Greberg, Jenny
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Salama, Abubakary
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Skawina, Bartlomiej
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Alternative Process Flow for Underground Mining Operations: Analysis of Conceptual Transport Methods Using Discrete Event Simulation2016In: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 6, no 3, article id 65Article in journal (Refereed)
    Abstract [en]

    As the near surface deposits are being mined out, underground mines will increasingly operate at greater depths. This will increase the challenges related to transporting materials from deeper levels to the surface. For many years, the ore and waste transportation from most deep underground mines has depended on some or all of the following: truck haulage, conveyor belts, shafts, rails, and ore pass systems. In sub-level caving, and where ore passes are used, trains operating on the main lower level transport the ore from ore passes to a crusher, for subsequent hoisting to the surface through the shaft system. In many mines, the use of the ore pass system has led to several problems related to the ore pass availability, causing production disturbances and incurred cost and time for ore pass rehabilitation. These production disturbances have an impact on the mining activities since they increase the operational costs, and lower the mine throughput. A continued dependency on rock mass transportation using ore passes will generate high capital costs for various supporting structures such as rail tracks, shaft extensions, and crushers for every new main level. This study was conducted at an existing underground mine and analyzed the transport of ore from loading areas at the lower levels up to the existing shaft points using trucks without employing ore passes. The results show that, when the costs of extending ore passes to lower levels become too great or ore passes cannot be used for production, haul trucks can be a feasible alternative method for transport of ore and waste up the ramp to the existing crusher located at the previous main level. The use of trucks will avoid installing infrastructure at the next main level and extending the ore passes to lower levels, hence reducing costs.

  • 7.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Automation of load haul dump machines2011Report (Other academic)
    Abstract [en]

    Load Haul Dump (LHD) vehicles are used in underground mines to load and transport ore and minerals. They can be manually or automatically operated. With an automatic system, the operator can be taken out of the mine and simultaneously control up to three LHDs, thus increasing both productivity and security for the personnel. There are a number of operation modes available for Load Haul Dump (LHD) vehicles and there are many criteria to consider when choosing the best one. This report fills a gap in the literature by mapping and describing the experiences and present status of the operation and maintenance of both automatic and manual LHDs as well as the existing navigation systems and techniques associated with underground automated loading and transportation.The commercially systems available today for automation of LHDs are supplied by Sandvik, Caterpillar and Atlas Copco. Automation focus have over the years gradually shifted from having fully automated fleets of vehicles to more flexible solutions with semi-automatic LHDs gaining safety as one of the main goals. Several issues must be resolved to maximize the benefits of automation. One is to improve maintenance, as this is crucial for an operation to work smoothly without the waste incurred by unplanned breakdowns.

  • 8.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Automation of Load Haul Dump machines: comparative performance analysis and maintenance modeling2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Load Haul Dump (LHD) machine and its operating environment create a complex system. Mine productivity depends on the operation of the LHDs and on the mining environment, including fragmentation, size of boulders, navigation techniques etc. Traditional navigation techniques require a lot of infrastructure to accommodate automatic operation. From fully automated fleets of vehicles, the focus of automation has gradually widened to include more flexible solutions, such as semi-automatic LHD machines, with safety as a main goal. The automatic system used for semi-automation is different from that used for fleet automation in that less infrastructure is needed, and the operator controls only one vehicle at a time. A semi-automatic LHD machine can operate in either manual or automatic mode depending on the need and situation. Several issues must be resolved to maximise the benefits of automation. One is to improve the maintenance strategy, especially preventive maintenance, as it is crucial to avoid the loss of time incurred by unplanned breakdowns. Another issue is the complexity of the mining environment; external disturbances such as oversized boulders, road maintenance etc. can throw the entire investment in automation into question.The purpose of this thesis is to explore the maintenance actions connected to automated LHDs as well as the factors influencing the operation of the machine. Research methods include a literature review, unstructured interviews, and data collection and integration. Reliability analysis, fault tree analysis and Markov modeling were performed to comparatively analyse manual and automatic LHDs.This thesis presents an approach to evaluate the performance of manual and semi-automatic LHD machines. It describes the maintenance procedures of automatic LHD machines. It includes a study of the reliability of LHD machines with special attention to automatic operation. It studies the operating environment’s effect on automatically operated LHDs compared to manually operated LHD machines, identifies the external disturbances affecting the automatic operation of LHD machines, and introduces a new way of modeling the maintenance and environmental disturbances to determine the best operation mode for the LHD machine.The analysis shows that the production performance of manual and semi-automatic LHD machines is similar. When it comes to the maintenance performance, hydraulic and electric systems are still the biggest reason for machine downtime but the stops are usually short, which means that LHD machines can start producing relatively soon after failure. However, the automatic LHD machine has more time spent in the workshop for the transmission and engine than the manual LHD machine. The difference in reliability between the machines regarding the engine is not significant. But for the transmission there is a verified difference. One possible reason for the difference in transmission reliability could be engaging/disengaging gears when the machine is in automatic mode.The analysis of the operating environment shows that LHDs suffer from mining related, machine related and/or automatic system related disturbances. Seventy-five percent of the stops causing idle time for LHD machines are related to the operating environment. Better fragmentation of rock to avoid big boulders, better constructed roads to minimise the need for road maintenance etc. are keys to the successful operation of automated LHDs.Fault tree models and reliability block diagrams are effective tools for evaluating the reliability of a system but it can be difficult to include mining related disturbances. Therefore, in this thesis, Markov models are introduced to describe disturbances affecting LHD machines and to identify possible differences between manual and semi-automatic LHDs. A fault tree model can classify and analyse failures but cannot show changes between states; this is something a Markov model can handle. The proposed Markov model built for the application shows that the best mode, from an operational point of view, is semi-automatic operation due to its flexibility handling disturbances of different kinds, especially those that are mining related.

  • 9.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Dependability assurance for automatic load haul dump machines2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Load Haul Dump (LHD) machines are used in underground mines to load and transport ore and minerals. Loading and hauling blasted ore from drawpoint to dumping point constitute a significant portion of the production costs for mining companies. There are a number of operation modes available for LHDs, and there are many criteria to consider when selecting the best one. The use of automated LHDs has been widely discussed due to the potential to increase productivity. The increasing focus on safety and ergonomics also gives an edge to automatically operated loaders over manually operated ones. Mine managers must decide when it is preferable to use manually operated loaders and when to complement or replace these with automatic ones. Automation focus has over the years gradually shifted from having automated fleets of vehicles to the more flexible solutions with semi-automatic LHDs gaining safety as one of the main goals. Several issues must be resolved to maximize the benefits of automation. One is to improve maintenance, and moving from operatorassisted “fail and fix” to planned maintenance. Since the operator is removed from the machine during automatic operation and maintenance staff is not always available on short notice, it is crucial to increase planned maintenance to maximize the investment in automation. Another issue is the complexity of the mining environment, including both the infrastructure and external disturbances like oversized boulders and road maintenance, as these can throw the entire investment in automation into question. The purpose of this thesis is to explore the maintenance actions connected to automated LHDs as well as the factors influencing the dependability of the machine. Research methods include a literature review, interviews, and data collection and analysis. Real time process data, operation and maintenance data have been refined, integrated and aggregated to make a comparative analysis of manual and automatic LHDs. The analysis show that 75% of the stop occasions causing idle time for LHDs relate to the operating environment, 21.5% pertain to machine related issues and 3.5% are related to the infrastructure of the automatic system installed in the mine. There is no difference in what kind of maintenance actions that are taken for manually and automatically operated LHDs, but there is a difference in what type of failures that occurs more frequently for the different operation modes. For automation of LHDs too much unplanned repairs and maintenance work significantly reduces the overall availability and can jeopardize the entire investment in automation. The difference between the semi-automatic and the manual LHD was found to be very small in terms of maintenance cost versus produced number of tons. However, a semi-automated LHD is an optimal machine regarding the ability to adapt to reconfiguring the operation mode to meet demands such as safety, flexibility and productivity.

  • 10.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Heyns, Stephan
    Division of Structural Mechanics, Pretoria.
    Fusion of production, operation and maintenance data for underground mobile mining equipment2012In: The Ninth International Conference on Condition Monitoring and Machinery Failure Prevention Technologies, 2012, Vol. 2, p. 783-791Conference paper (Refereed)
    Abstract [en]

    For integration purposes, a data collection and distribution system based on the concept of cloud computing could be possible to use for collection of data or information pertaining from various sources of data. From a maintenance point of view, the benefit of cloud computing is that information or data may be collected on the health, variability, performance or utilization of the asset. It is especially useful in data mining where different types of data of different quality must be integrated. This paper discusses the concept and presents one example from the underground mining industry.

  • 11.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Johansson, Daniel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Face to Surface: a fragmentation study2016Report (Refereed)
    Abstract [en]

    As ore grades have decreased and the mining depth has increased over the past few decades, other characteristics than ore grade and tonnage are becoming important. The underground mining process, from in-situ rock mass characteristics to the final mill product with fully liberated minerals, consists of a chain of unit operations that impact, and are influenced by, fragmentation. This report presents the baseline mapping of the project “From Face to Surface”, studying the effects of fragmentation on the process flow in an underground SLC mine. It analyses the underground unit operations in detail, from mine planning to shafts, and maps the blast fragmentation’s effect on the process flow. The goal is to provide a deeper understanding of fragmentation´s effect on different unit operations. The objective is to describe the mining operation at Luossavaara-Kiirunavaara AB (LKAB) and identify key areas for improving fragmentation. To understand how fragmentation influences different operations in the mine, the project conducted a literature study, collected data and interviewed mine personnel in LKAB’s Malmberget mine. Data were collected from the mine’s internal systems, such as GIRON, WOLIS, IP21 and a local drilling data system. The interviews were conducted in cooperation with research personnel from the mine.This baseline mapping shows that the mining operation in Malmberget is affected by fragmentation in several ways. For some unit operations, the fragmentation has a large impact, while for others, it has none at all. The influence of fragmentation starts with the loading operation after the initial blasting and ends with the crushing operation. For the former, boulders are the largest problem, as they cause a great deal of idle time, either when they have to be moved to a separate drift for secondary blasting or when they create hang-ups in the ore passes. When boulders are dumped into the ore passes, they risk damaging the ore pass walls. If boulders create a hang-up, it has to be removed. If the hang-up must be removed with explosives, there is a risk of further damaging the ore pass. In addition, the toxic fumes created by the explosives hinder production until the pass is ventilated. Finally, hang-ups affect the transportation operation as the trucks cannot use an ore pass blocked by a hang-up or closed for ventilation of toxic fumes. There is also a slight possibility that a boulder which does not get stuck in the ore pass will get stuck on a truck. The last operation affected by fragmentation is crushing; boulders and large fragments risk creating a hang-up in the crusher. There are no reports of problems related to fragmentation after this point.The results suggest that further work and mine trials are required in the following areas: drilling, loading, ore passes and crushers.

  • 12.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Jonsson, Kristina
    LKAB.
    Johansson, Daniel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    From Face to Surface: a Fragmentation Study2016In: Seventh International Conference & Exhibition on Mass Mining : (MassMin 2016), Sydney: The Australian Institute of Mining and Metallurgy , 2016, p. 555-562Conference paper (Refereed)
    Abstract [en]

    The underground mining process, from in-situ characteristics of the unmined rock mass to the final mill product with fully liberated minerals, consists of a chain of unit operations. Some of them influence fragmentation while fragmentation impacts others. From a production point of view, fragmentation is a key parameter for the proper functioning of many unit operations and affects total production; it influences the ability to load, haul and crush the rock later in the process. Fragmentation varies because of rock mass strength, the presence of joints, the chosen explosive, specific charge (kg/m3) and quality of drill holes. The efficiency and result of unit operations such as drilling, blasting, loading and crushing depend on the rock properties which vary throughout a mine. Generally speaking, operations are not well adapted to the actual rock properties, leading to a non-optimised flow in production. This paper presents the initial part of a project that will build knowledge on the impact of fragmentation on each step of the production chain in an underground mine. It identifies the key parameters of fragmentation which influence the overall energy consumption and productivity in a mining operation through interviews, mine visits and a literature review. In the subsequent stages of the project, a number of field tests in the case study mine will address important segments of the production process where fragmentation is a major obstacle to improvements. Optimising the entire process, rather than isolated unit operations, will lead to increased productivity, decreased amount of interruptions and lower energy consumption.

     

  • 13.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Lipsett, Michael
    Mechanical Engineering, University of Alberta, Edmonton.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Development of a Markov model for production performance optimisation: Application for semi-automatic and manual LHD machines in underground mines2014In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, no 5, p. 342-355Article in journal (Refereed)
    Abstract [en]

    This paper compares three ways to operate a load haul dump (LHD) machine, manual operation, automatic operation (fleet operation) and semi-automatic operation, to find the best operating mode. In a fault tree analysis, different failures are classified and analysed, but the way to recover from certain states is not accounted for, which is something a Markov model can handle. The paper is based on the analysis of real data from an underground mine. A Markov model has been built for mining application and it is shown that a semi-automatic LHD has the highest probability of being in a productive state since it has the advantage of changing operating modes (manual and automatic) depending on the need and situation. Hence, the semi-automatic LHD is the best choice from an operational point of view. The paper fills a gap in the literature on manual vs. automatically operated LHDs by providing a new way of evaluating the operating mode of LHDs using Markov modelling, while considering the operating environment.

  • 14.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Paraszczak, Jacek
    Department of Mining, Metallurgical and Materials Engineering, Université Laval, Quebec City.
    Tuleau, Jocelyn
    Department of Mining, Metallurgical and Materials Engineering, Université Laval, Quebec City.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Impact of technical and operational factors on effectiveness of automatic load-haul-dump machines2017In: Mining Technology, ISSN 1474-9009, E-ISSN 1743-2863, Vol. 126, no 4, p. 185-190Article in journal (Refereed)
    Abstract [en]

    The use of automatic load-haul-dump (LHD) machines in underground metal mines is a promising way to overcome some of the challenges now facing mining companies. They offer several potential benefits over man-operated units, mostly in terms of safety and health of the workers, but also in terms of higher availability, increased productivity, and reduced mining cost. That said, using such systems at their full capacity is a challenging and complex task. In this context, after describing some commercially available equipment and systems, the paper examines factors affecting reliability, availability and productivity of automatic LHDs and notes several technical and operational concerns.

  • 15. Gustafson, Anna
    et al.
    Parida, Aditya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Nissen, Arne
    Optimizing productivity through performance measures for underground mining industry2008In: MassMin 2008: Proceedings of the 5th International Conference and Exhibition on Mass Mining, Lulea, Sweden 9-11 June 2008 / [ed] Håkan Schunnesson; Erling Nordlund, Luleå: Luleå tekniska universitet, 2008, p. 371-378Conference paper (Refereed)
    Abstract [en]

    Performance needs to be measured in order to manage the business goals. Performance measurement (PM) has caught the imagination of almost all industries in the last decade. A number of PM frameworks are in use by different industries. Due to global competition and high dynamic market demand, the pressure on the process industries like; the mining industries, is too high. In order to manage and meet the challenging market demands of high productivity, mining industries are trying to apply the concept of PM and performance measures. Before applying performance measures for PM, the production process need to be organized and the management needs to be fully committed for PM implementation. PM measures can be divided into hard and soft measures, which are necessary to monitor, control and measure the productivity. Hard measures like the technical, productivity and financial measures can be well defined and relatively easy to control, where as soft parameters pertaining to human factors like; competence, motivation and organizational climate are critical and hard to measure. In this paper, the authors have discussed the concept of performance measurement and measures for achieving desired productivity. Based on their experience of a related project, the authors have discussed the performance measures for LKAB underground mining industry.

  • 16.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Maintenance indicators for underground mining equipment: a case study of automatically versus manually operated LHD machines2011In: Proceedings of the 24th International Congress on Condition Monitoring and Diagnosis Engineering Management: COMADEM 2011 / [ed] Maneesh Singh; Raj B.K.N. Rao; J.P. Liyanage, Stavanger: COMADEM International, 2011, p. 1205-1214Conference paper (Refereed)
    Abstract [en]

    Key Performance Indicators (KPIs) are performance measures directly related to the overall goals of the company and some of them depend on the maintenance function. In mining companies top managers use the maintenance cost per unit versus budget as one of the KPIs. However many other technical, organizational and economical parameters in a company can be helpful during the decision making process.In this paper the productivity of Load-Haul-Dump machines (LHDs), that is obtained when manual and/or automatic mode are used, are being analysed. The correlation between the productivity and the maintenance KPIs as well as the issues related to the acquisition of data will be shown in this paper highlighting the complexity of getting accurate decision process parameters. It is recognized that the data for some of the components and failure modes originating from different sources are not compatible. This situation must be considered when compiling the data, especially to permit comparison the data should be made compatible. The problem of incompatibility is most severe when dealing with demand related failures. The philosophy and mechanisms of demand related failures as well as the methods used to denote the time and demand related failures in common form have to be taken into account.

  • 17.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    TPM framework for underground mobile mining equipment: a case study2011Conference paper (Refereed)
    Abstract [en]

    In underground mines, mobile mining equipment is critical to the production system. Drill rigs for development and production, vehicles for charging holes, LHDs for loading and transportation, scaling rigs and rigs for reinforcement and cable bolting are all important units in the process to generate a continuous ore flow. For today’s mining companies, high equipment availability is essential to reduce operational and capital costs and to maintain high production. High and controllable reliability is also important especially in attempts to automate the production equipment. This paper compares existing maintenance work in a Swedish and a Tanzanian mine. The various maintenance procedures are identified and evaluated based on a TPM framework.

  • 18.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Production and maintenance performance analysis: manual versus semi-automatic LHDs2013In: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 19, no 1, p. 74-88Article in journal (Refereed)
    Abstract [en]

    Purpose – The purpose of this paper is to evaluate and analyse the production and maintenance performance of a manual and a semi-automatic Load Haul Dump (LHD machine to find similarities and differences.Design/methodology/approach – Real time process-, operational- and maintenance data, from an underground mine in Sweden, have been refined and aggregated into KPIs in order to make the comparison between the LHDs.Findings – The main finding is the demonstration of how production and maintenance data can be improved through information fusion, showing some unexpected result for maintenance of automatic and semi-automatic LHDs in the mining industry. It was found that up to one third of the manually entered workshop data are not consistent with the automatically recorded production times. It is found that there are similarities in utilization and filling rate but differences in produced tonnes/machine hour between the two machines.Originality/value – The originality in this paper is the information fusion between automatically produced production data and maintenance data which increases the accuracy of reliability analysis data. Combining the production indicator and the maintenance indicator gives a common tool to the production and maintenance departments. This paper shows the difference in both maintenance and production performance between a manual and semi-automatic LHD.

  • 19.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    The influence of the operating environment on manual and automated load-haul-dump machines: a fault tree analysis2013In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 27, no 2, p. 75-87Article in journal (Refereed)
    Abstract [en]

    The automated load-haul-dump (LHD) machines have the potential to increaseproductivity and improve safety, but there are many issues to be considered when optimising the operation of LHDs. Today’s focus on improved equipment reliability is part of the problem, and another difficult issue is the special conditions and constraints of the operating environment. For automated LHDs, the latter issue is even more important, as humans have been removed from the production area and are not close by to solve the problems. The purpose of this paper is to find the causes of LHD idle time and to study their impact on the operation of LHDs. In this study, real-time process data and maintenance data from an underground mine in Sweden have been refined and integrated. The study takes into account the complexity of the mine environment, discusses the factors to be considered when optimising and automating the operation and uses fault tree analysis (FTA) to analyse the idle time.

  • 20.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ghosh, Rajib
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Bolting Procedures in Outokumpu’s Kemi Mine2014In: Mine Planning and Equipment Selection: Proceedings of the 22nd MPES Conference, Dresden, Germany, 14th – 19th October 2013 / [ed] Raj Singhal ; Carsten Drebenstedt, Encyclopedia of Global Archaeology/Springer Verlag, 2014, Vol. 3, p. 411-420Conference paper (Refereed)
    Abstract [en]

    The working environment for ground support installation in mines has improved a lot during the last 20-30 years, with more and more mechanized installations of the different ground support elements such as bolts, cable bolts and screen. However ground support installation productivity has not followed the same development curve. In fact, its productivity has more or less remained constant and in some cases has even fallen if, as an example, comparisons are made between the manual and mechanized installations of bolts. One reason for this is that modern mechanised bolt rigs are very complex, capable to perform many tasks. To be able to fully utilize this equipment’s capability a different level of maintenance and product support is required. This paper describes the bolting process in Outokumpu’s Kemi mine that has a very interesting procedure for bolt installation and has also paid an unsurpassed attention to the maintenance procedures to improve productivity.

  • 21.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Reliability analysis and comparison between automatic and manual load haul dump machines2015In: Quality and Reliability Engineering International, ISSN 0748-8017, E-ISSN 1099-1638, Vol. 31, no 3, p. 523-531Article in journal (Refereed)
    Abstract [en]

    Today's trend of replacing manually operated vehicles with automated ones will have an impact not only on machine design, working environment and procedures but also on machine breakdown and maintenance procedures. In the harsh environment of underground mines, the transition from manual to automatic operation is believed to fundamentally change the basis for break downs, maintenance and machine design. In this paper, differences and similarities between manual and automatic underground loading equipment is analysed from a reliability point of view. The analysis is based on a case study performed at a Swedish underground mine. In the contrary of common thoughts, this paper proves that there is a difference between the manual and semi-automatic machines and in particular for the transmission, in favour of the manual one. This paper also shows a path for detailed reliability analysis, and the results may be used for improving maintenance programmes for other types of mobile equipment

  • 22.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Timusk, Markus A.
    Division of Engineering, Laurentian University, Sudbury.
    Hauta, Rebecca
    Division of Engineering, Laurentian University, Sudbury.
    Productivity of rock reinforcement: Methodology development2016In: The Southern African Journal of Mining and Metallurgy, ISSN 2225-6253, E-ISSN 1543-9518, Vol. 116, no 12, p. 1127-1134Article in journal (Refereed)
    Abstract [en]

    The working environment for ground support installation in mines has improved during the last 20-30 years, with more mechanized equipment for installation of ground support elements such as bolts, cable bolts, and screens. Ground support installation productivity has, however, not followed the same development curve, remaining more or less constant. In some cases, for example the mechanized installation of bolts, productivity has even dropped. One reason for this is that modern mechanized bolt rigs are complex. In this paper we evaluate manual and mechanized ground support systems, propose a way to measure the productivity of bolt rigs, and make relevant comparisons between different mines and equipment. Some productivity measures for rock reinforcement are suggested, using productivity results from eight case study mines

  • 23.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sundqvist, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sjödin, Erik
    Greberg, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Conceptual models for mining at greater depths: Automated bolt rigs and scaling rigs2016Manuscript (preprint) (Other academic)
    Abstract [en]

    One of the challenges that underground mines face today is the deepening of the mines. This, together with lower grades of the deposits, makes the mines strive for higher productivity and lower costs. By introducing autonomous vehicles, the operators will be removed from the face, and thus safety for operators will be improved. Since autonomous vehicles are scheduled to operate during breaks, there is a potential for a productivity increase. The goal with this study was to determine if and to which degree autonomous bolt rigs and scaling rigs can improve the productivity in a deep underground mine.The research is based on data collected during 2013 from New Boliden AB’s Kristineberg mine in Sweden. A simulation tool, SimMine, was used for analyzing the effects of operational changes and for simulation of parameters that are difficult to estimate, such as traffic congestions. A number of scenarios were simulated and compared to the base case with focus on productivity.It can be concluded that the simulation scenarios using faster, manually operated vehicles shows a productivity increase, and that the automated vehicles further improved the productivity increase. The largest productivity increase comes however from faster vehicles, and not from the automation itself.

  • 24.
    Hassan, Syed Alley
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Greberg, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Transition from surface to underground mining in the Arctic region: A case study from Svartliden Gold Mine, Sweden.2014In: Mine Planning and Equipment Selection: Proceedings of the 22nd MPES Conference, Dresden, Germany, 14th – 19th October 2013 / [ed] Carsten Drebenstedt; Raj Singhal, Germany: Encyclopedia of Global Archaeology/Springer Verlag, 2014, Vol. X, p. 1397-1408Conference paper (Refereed)
    Abstract [en]

    Gold ores often consist of nuggets associated with quartz veins. In other ore types gold can be found as a by-product to pyrite. For both types, mine planning of scattered veins type deposits is often complicated regarding both mine design and production scheduling. Despite the cold climate in the Arctic region, near surface deposits are initially mined with open pit mining. As the mine goes deeper, the stripping ratio and the transportation cost increases which economically limit the possibility to continue the project with open pit mining. The transition to underground mining, with gradually decreasing production from an open pit, near its final depth, and with gradually increasing production from newly developed underground production areas, require detailed planning and production scheduling to avoid production delays and maintaining a high cash flow. This paper high-lights the main operational aspects of the Svartliden gold mine in Sweden and in particular how a scattered gold deposit during harsh cold weather conditions was dealt with. The on-going transition from surface to underground mining and the applied concept of minimizing own personnel in favour of national and local contractors for production purposes are also discussed.

  • 25.
    Morant, Amparo
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Söderholm, Peter
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Safety and Availability Evaluation of Railway Signalling Systems2016In: Current Trends in Reliability, Availability, Maintainability and Safety: An Industry Perspective / [ed] Uday Kumar; Alireza Ahmadi; Ajit Kumar Verma; Prabhakar Varde, Encyclopedia of Global Archaeology/Springer Verlag, 2016, p. 303-316Conference paper (Refereed)
    Abstract [en]

    The purpose of this paper is to evaluate the safety and availability of railway signalling systems using Markov models. Since a failure of the signalling systems still allows operation of the railway, it is not sufficient to study their safety and availability by considering only the failures and delays. The safety and availability are evaluated, handling both repairs and replacements by using a Markov model. The model is validated with a case study of Swedish railway signalling systems with different scenarios. The results obtained show that the probability of being in a state where operation is possible in a degraded mode is greater than the probability of not being operative at all, which reduces delays but requires other risk mitigation measures to ensure safe operation.

  • 26.
    Morant, Amparo
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Söderholm, Peter
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Larsson-Kråik, Per-Olof
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Safety and availability evaluation of railway operation based on the state of signalling systems2017In: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 231, no 2, p. 226-238Article in journal (Refereed)
    Abstract [en]

    A framework is presented to evaluate the safety and availability of the railway operation, and quantifying the probability of the signalling system not to supervise the railway traffic. Since a failure of the signalling systems still allows operation of the railway, it is not sufficient to study their effect on the railway operation by considering only the failures and delays. The safety and availability are evaluated, handling both repairs and replacements by using a Markov model. The model is verified with a case study of Swedish railway signalling systems with different scenarios. The results show that the probability of being in a state where operation is possible in a degraded mode is greater than the probability of not being operative at all, which reduces delays but requires other risk mitigation measures to ensure safe operation. The effects that different improvements can have on the safety and availability of the railway operation are simulated. The results show that combining maintenance improvements to reduce the failure rate and increase the repair rate is more efficient at increasing the probability of being in an operative state and reducing the probability of operating in a degraded state.

  • 27.
    Paraszczak, Jacek Jack
    et al.
    Department of Mining, Metallurgical and Materials Engineering, Université Laval, Quebec City.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Technical and operational aspects of autonomous LHD application in metal mines2015In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 29, no 5, p. 391-403Article in journal (Refereed)
    Abstract [en]

    Due to safety concerns, automation of load-haul-dump (LHD) machines receives considerable attention from the mining industry. This paper analyses and discusses the issues and problems related to implementation and use of autonomous LHDs in underground metal mines. It presents the need for safety measures, infrastructure and discusses technical problems encountered. The paper looks also into technical and operational issues (reliability, maintainability, utilisation, production rate, etc.) as compared to conventional manually operated machines. Conclusions focus mostly on the aspects requiring attention before and after the implementation of autonomous loading systems in order to maximise the chances that they deliver expected benefits

  • 28.
    Salama, Abubakary
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Greberg, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Conceptual models regarding mine layout/infrastructure and process flow at greater depths: A literature review on haulage systems2014Report (Other academic)
    Abstract [en]

    This report is part of the work done by Luleå University of Technology within the EU 7th framework project I2Mine, Innovative Technologies and Concepts for the Sustainable and Intelligent Deep Mine of the Future. The work is performed within work package 2 Novel mining and underground processing methods, subtask 2.1.1 Novel mining methods and processes for deep, steeply dipping orebodies. This subtask aims at identifying new conceptual methods and processes for mining of deep, steeply dipping orebodies. The literature review presented in this report is aiming at identifying haulage systems that might be applicable for the given conditions, and serves as input for the future work within subtask 2.1.1 which is carried out by the research subject Mining and Rock Engineering at LTU together with LKAB and Boliden from November 2011 to November 2015.

  • 29.
    Salama, Abubakary
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Greberg, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Skawina, Bartlomiej
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Analyzing energy consumption and gas emissions of loading equipment in underground mining2015In: CIM Journal, ISSN 1923-6026, Vol. 6, no 4, p. 179-188Article in journal (Refereed)
    Abstract [en]

    In an environment of rising energy prices and mining at greater depths, cost-efficient loading and hauling equipment is essential. Conducted at an underground mining operation, this study analyzes the energy consumption and gas emissions of diesel and electric load-haul-dump machines (LHDs) with similar bucket capacities. Based on energy prices from the first quarter of 2014, results of discrete event simulation show that energy costs for diesel and electric LHDs are US$0.24/t and US$0.07/t, respectively. Also, diesel LHDs emit 2.68 kg CO2 per litre of diesel fuel, whereas using electric machines reduces the need for ventilation to mitigate engine heat and emissions and reduces energy costs.

  • 30.
    Schunnesson, Håkan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Gustafson, Anna
    Kumar, Uday
    Performance of automated LHD machines: a review2009Conference paper (Refereed)
    Abstract [en]

    The importance of LHD (Load Haul Dump) machines in most mine operating systems is evident today. The cost of operation and maintenance is one of the challenges, while high availability and reliability are others. The latter will be increasingly important when automatic LHD machines are used more frequently. A key factor for automated LHD system is the planned maintenance process, as all corrective maintenance or accidental break-downs rapidly deteriorate the production system where operators are not present and maintenance personnel not available on short notice. A challenge for manufacturers is to improve the engineering design of their machine and related components (hydraulic systems etc) so as to make them more reliable and also making the machine easy to maintain. The demands on the overall communication systems and new and higher competence and skills needs on operation and maintenance personnel are a few factors that make many mines reluctant to the higher investments in Automated LHD systems. This paper reports some experiences with automated LHD machines in Scandinavia and the rest of the world and examines some of the issues that make the application of automatic LHD machines restricted by large operators and prohibitive by small mines. It also deals with the maintenance aspects of automated LHD systems and provides some initial considerations from a major Scandinavian research project in the field.

  • 31.
    Shekhar, Gurmeet
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Boeg-Jensen, Patricia
    Luossave-Kiirunavaara AB, Kiruna, Sweden.
    Malmgren, Lars
    Luossave-Kiirunavaara AB, Kiruna, Sweden.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Draw control strategies in sublevel caving mines: A baseline mapping of LKAB's Malmberget and Kiirunavaara mines2018In: The Southern African Journal of Mining and Metallurgy, ISSN 2225-6253, E-ISSN 1543-9518, Vol. 118, no 7, p. 723-733Article in journal (Refereed)
    Abstract [en]

    The Malmberget and Kiirunavaara mines are the two largest underground iron ore operations in the world. Luossavaara-Kiirunavaara AB (LKAB) uses sublevel caving (SLC) to operate the mines while maintaining a high level of productivity and safety. The paper enumerates the loading criteria and loading constraints at the mines and outlines details of mine design, layout, and geology affecting the draw control. A study of the various draw control strategies used in sublevel caving operations globally has also been done to establish the present state-of-the-art. An analysis of the draw control and loading operations at the Malmberget and Kiirunavaara mines is summarized using information collected through interviews, internal documents, meetings, and manuals. An optimized draw control strategy is vital for improving ore recovery and reducing dilution in SLC. Based on the literature review and baseline mapping study, a set of guidelines for designing a new draw control strategy is presented. The draw control strategy at Malmberget and Kiirunavaara is guided by a bucket-weightbased drawpoint monitoring system that is part of the overall framework. Both mines employ a draw control strategy that considers the production requirements and mining constraints while regulating the loading process through an empirical method based on bucket weights and grades. However, in the present scenario of fluctuating metal prices and increasing operational costs a new draw control strategy is needed which is probabilistic in nature and can handle the uncertainties associated with caving operations.

  • 32.
    Shekhar, Gurmeet
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Boeg-Jensen, Patricia
    LKAB.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Draw control optimization along the production drift in sublevel caving mines2016In: Seventh International Conference & Exhibition on Mass Mining : (MassMin 2016), Sydney: The Australian Institute of Mining and Metallurgy , 2016, p. 241-249Conference paper (Refereed)
    Abstract [en]

    The amount of material extracted from each blasted ring in sublevel caving mines is vital when deciding the overall mine production target. The orientation of the production drifts is normally perpendicular to the strike of the orebody, and rings are blasted from the hanging wall side to the footwall side in a retreating manner. For an inclined orebody, a given ring will contain different amounts of material based on its relative position along the production drift. This layout creates a distinctive problem with respect to the extraction ratio optimisation along the axis of the production drift. This paper describes the current drawpoint control strategy practiced at LKAB and presents the variation of drawpoint performance parameters along the production drifts. It uses automatically generated data from a bucket weighing system that measures tonnage drawn per bucket, and it classifies the blasted rings into four zones based on their relative position along the production drift. It considers the loading procedure for blasted rings at Kiirunavaara mine and analyses the variations in drawpoint performance along the production drift. The paper finds that although the current draw control strategy is sensitive to ring position along the drift, it could be modified to optimise the final extraction ratio.

  • 33.
    Shekhar, Gurmeet
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hersinger, Anders
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Jonsson, Kristina
    Luossavaara-Kiirunavaara AB, Kiruna, Sweden.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Development of a model for economic control of loading in sublevel caving mines2019In: Mining Technology:Transactions of the Institutions of Mining and Metallurgy, ISSN 2572-6668, Vol. 128, no 2, p. 118-128Article in journal (Refereed)
    Abstract [en]

    This paper presents an economic model for optimizing loading at the draw point in sublevel caving (SLC) operations. The input data consist of estimated bucket grades based on bucket weights from Load Haul Dump machines. This information, together with average operational mining costs, was used to create an economic model providing a real-time economic assessment of the draw point performance for SLC rings. The results demonstrate the importance of continuous draw point monitoring to optimize SLC operations. The proposed model provides an economic assessment of operating draw points and will help mine personnel to decide when to stop loading from a blasted ring. It can also help mine management understand the complexity of material flow in SLC operations. Finally, it provides operational flexibility for the mine to optimize loading at the draw point by increasing ore recovery while maintaining operational control of draw point performance.

  • 34.
    Shekhar, Gurmeet
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Draw Control Strategy and Resource Efficiency in Sublevel Caving: State-Of-the-Art2016Report (Other academic)
    Abstract [en]

    Sublevel caving is an underground mass mining method used for extracting different types of ores from the earth crust. Mines using sublevel caving (SLC) as the primary mining method are generally highly mechanized with standardized and independent unit operations. Mine development for caving operations are similar to other underground mining methods, however, the scale of production drilling and blasting performed in caving operations including SLC are larger than many other underground mining methods (such as room and pillar or cut and fill). Loading of the material from the production face in sublevel caving is facilitated by the flow of material under gravity into the production face. A large amount of material is loaded from a limited opening termed as the draw point. Different unit operations (drilling, blasting, loading and transportation) are performed in isolation with each other which leads to standardized procedures and safe operation. The mine design allows for operational agility with respect to ore geometry and inclination. These features give SLC an advantage over other mining methods. However, SLC demands a caving conducive geology along with a large ore footprint. The mining method also registers higher percentage of dilution and ore loss compared to non-caving mining methods. Material flow in SLC has been studied extensively in the past five decades and different methods have been used to simulate material flow in caving operations. Physical models of different scales has been designed for simulating material flow by using sand, gravel or rocks and studying the movement of material inside the model. Initial physical models showed an ellipsoidal zone above the draw point from which material flowed into the draw point. However, subsequent modelling results disagreed with this notion of material flow. Numerical modelling techniques have also been applied to simulate material flow. The models were calibrated against mine or mill production data for optimization. Currently, marker trials are being used to understand material flow in SLC. Markers (numbered steel rods, RFID enabled markers) are installed in boreholes drilled inside the burden of a production ring and based on the recovery sequence of markers, material flow is predicted. Results from physical models, numerical models and marker trials along with mine experience have been used in the past to design draw control strategy for SLC operation. Initial draw control techniques were based on the assumption of uniform flow of material. But with the advancement in modelling techniques, draw control strategies have also changed. Ore flow simulation techniques developed to simulate material flow are being applied to predict the ore grade at draw point and hence help in draw control during the loading process. Recent draw control strategies in some mines have evolved to include production data and metal prices to optimize the loading process in SLC. Monitoring of the ore grade at the draw point is crucial in controlling dilution and increasing ore recovery. Present draw point monitoring technique predicts ore grade by exploiting the differences between ore and waste. The difference between ore and waste can be detected through visual observations, assay sampling or weight measurements. Draw point monitoring gives data for both regulation and calibration of draw control strategies, and provides important information regarding dilution and ore recovery during the loading process. Understanding material flow is vital for improving different aspects of SLC operation but draw control for SLC is an operational activity which regulates the loading process for a given mine design and material flow conditions. Therefore, an effective draw control requires a constant monitoring system and a constant calibration of the loading criteria’s through draw point monitoring for reducing dilution and improving ore recovery.

  • 35.
    Shekhar, Gurmeet
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Loading Procedure and Draw Control in LKAB’s Sublevel Caving Mines: Baseline Mapping Report2017Report (Other academic)
    Abstract [en]

    Sublevel caving (SLC) is an underground mass mining method used to extract iron ore from the Kiirunavaara and Malmberget mines. Although both mines use SLC as the mining method, their implementation varies in terms of mine design, ring design and draw control strategy. The Kiirunavaara mine has a continuous and massive ore deposit which allows a standard mine design layout, while the Malmberget mine has scattered ore bodies with varying mine design parameters. The two mines also employ different opening techniques for production drifts.

    Luossavaara-Kiirunavaara AB (LKAB) uses different information systems to run these highly mechanized mines. The information generated by the various systems is transferred between the different unit operations and is used to optimize the mining process. The mines use GIRON to create, store and display different information related to the mining operation. Information on all unit operations is stored in a number of databases inside GIRON. The two loading related information systems which support the loading operation are the Wireless Loader Information System (WOLIS) and the Loadrite system. The Loadrite system measures the bucket weights being loaded by the Load Haul Dump (LHD) machines at the draw point. This information, along with information on planned ring tonnage etc., is displayed to the LHD operator inside the LHD machine using WOLIS. WOLIS provides online data on the ring performance such as grades, tonnage extracted etc. to the LHD operators and the production team.

    In SLC, the different aspects of loading at the draw point include loading procedures, loading issues, loading criteria and loading constraints. Loading procedures include the practices and precautions taken during loading at the draw point. Loading issues include events observed at both mines, such as brow failure, ring freeze, hang-ups etc. Although most loading issues are handled in a similar manner, hang-up handling techniques are different at the Kiirunavaara and Malmberget mines. Loading criteria and constraints along with the nature of material flow collectively provide a complete understanding of the draw control strategy. Loading criteria comprise a set of rules or guidelines for loading and closing a draw point. LKAB uses WOLIS to enforce the loading criteria for its SLC operations. Loading constraints include production constraints, grade control and mining constraints which must be followed for a safe and sustainable mining operation.

    A baseline analysis of the draw control and loading operations at the Kiirunavaara and Malmberget mines is summarized in this report using information collected through internal documents, meetings, e-mails and manuals.  

  • 36.
    Skawina, Bartlomiej
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Salama, Abubakary
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Svanberg, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    The effects of orepass loss on loading, hauling, and dumping operations and production rates in a sublevel caving mine2018In: The Southern African Journal of Mining and Metallurgy, ISSN 2225-6253, E-ISSN 1543-9518, Vol. 118, no 4, p. 409-418Article in journal (Refereed)
    Abstract [en]

    Orepass failure is a well-known problem in deep mines, and the risk of losing an orepass is associated with severe production disturbances. In the near future, one possible scenario in the Loussavaara Kiirunavaara Aktiebolag (LKAB) Malmberget mine is to concentrate the mining operation in fewer, but larger, production areas. In this paper we evaluate the effects of orepass loss on loading, hauling, and dumping operations and production rates using discrete event simulation, by simulating part of the Malmberget mine loading and hauling system under different environmental and operational constraints.

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