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  • 1.
    Hoseinie, Seyed Hadi
    et al.
    Department of Mining Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
    Al-Chalabi, Hussan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Comparison between Simulation and Analytical Methods in Reliability Data Analysis: A Case Study on Face Drilling Rigs2018Ingår i: Data, ISSN 2306-5729, Vol. 3, nr 2, artikel-id 12Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Collecting the failure data and reliability analysis in an underground mining operation is challenging due to the harsh environment and high level of production pressure. Therefore, achieving an accurate, fast, and applicable analysis in a fleet of underground equipment is usually difficult and time consuming. This paper aims to discuss the main reliability analysis challenges in mining machinery by comparing three main approaches: two analytical methods (white-box and black-box modeling), and a simulation approach. For this purpose, the maintenance data from a fleet of face drilling rigs in a Swedish underground metal mine were extracted by the MAXIMO system over a period of two years and were applied for analysis. The investigations reveal that the performance of these approaches in ranking and the reliability of the studies of the machines is different. However, all mentioned methods provide similar outputs but, in general, the simulation estimates the reliability of the studied machines at a higher level. The simulation and white-box method sometimes provide exactly the same results, which are caused by their similar structure of analysis. On average, 9% of the data are missed in the white-box analysis due to a lack of sufficient data in some of the subsystems of the studies’ rigs.

  • 2.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Context-driven mean residual life estimation of mining machinery2018Ingår i: International Journal of Surface Mining, Reclamation and Environment, ISSN 1389-5265, s. 486-494Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Maintenance is crucial to ensure production/output and customer satisfaction in the mining sector. The cost of maintenance of mechanised and automated mining systems is very high, necessitating efforts to enhance the effectiveness of maintenance systems and organisation. For effective maintenance planning, it is important to have a good understanding of the reliability and availability characteristics of the systems. Determining the Mean Residual Life (MRL) of systems allows organisations to more effectively plan maintenance tasks. In this paper, we use a statistical approach to estimate MRL and consider a Weibull proportional hazard model (PHM) with time-independent covariates to model the hazard function so that the operating environment could be integrated into the reliability analysis. The paper explains our methods for calculating the conditional reliability function and computing the MRL as a function of the current conditions. The model is verified and validated using data from the hydraulic system of LHD equipment in a Swedish mine. The results are useful to estimate the remaining useful life of such systems; the method can be used for maintenance planning, helping to control unplanned stoppages of highly mechanised and automated systems.

  • 3.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Rahimdel, Mohammad Javad
    Department of Mining Engineering, Sahand University of Technology, Tabriz, Iran.
    Taghizadeh Vahed, Amir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Fuzzy Risk Prioritization of the Failure Modes in Rolling Stocks2018Ingår i: / [ed] Kay Chen TAN, Roger JIAO, Surendra M GUPTA, Kongkiti PHUSAVAT and Min XIE, Piscataway, NJ: IEEE, 2018, s. 108-112Konferensbidrag (Refereegranskat)
    Abstract [en]

    Failure Mode and Effects Analysis (FMEA) is extensively used to identify and eliminate the potential failures in products, processes, designs, and services. In this approach, the detectability, occurrence and the severity of each identified failure mode need to be determined usually by a FMEA team. This paper aims to prioritize the failure modes of rolling stocks by integrating Analytical Hierarchy Process (AHP) and Risk Priority Number (RPN). To reduce the uncertainties and ambiguities, all calculations are done in the fuzzy environment instead of the crisp values. The importance degree of each failure mode is determined and then the overall fuzzy RPN is calculated. In this way, the critical failure modes are defined to make an efficient maintenance decision.

  • 4.
    Moosazadeh, Sayfoddin
    et al.
    Faculty of Mining Engineering, Sahand University of Technology, Tabriz.
    Aghababaie, Hamid
    Faculty of Mining Engineering, Sahand University of Technology, Tabriz.
    Hoseinie, Hadi
    Department of Mining Engineering, Isfahan University of Technology, Isfahan.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Simulation of tunnel boring machine utilization: A case study2018Ingår i: Journal of Mining & Environment, ISSN 2251-8592, Vol. 9, nr 1, s. 53-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Utilization is one of the main managerial factors that is applied for construction process analysis well. It directly affects the project duration and construction costs. Therefore, a utilization study in tunneling projects is essential. In this work, the utilization of an earth pressure balance Tunnel Boring Machine (TBM) in Tabriz urban railway project was studied using the Monte Carlo simulation approach. For this purpose, the unit operation during one working shift such as boring time, ring building time, and locomotive travel time was recorded and saved in data base. In addition, the general down times such as TBM and back-up system maintenance, surface and tunnel logistic maintenance, cutting tools’ replacement, and locomotive delay times were recorded and considered in simulation. The results of this work show that the mean simulated project duration time of case study TBM is approximately 859 shifts and close to the real data with a difference of 0.92%. Finally, the average estimated utilization factor was found to be approximately 14%.

  • 5.
    Hoseinie, Hadi
    et al.
    Department of Mining Engineering, Isfahan University of Technology.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Bagherpour, Raheb
    Department of Mining Engineering, Isfahan University of Technology.
    Failure mode and effect analysis (FEMA) in automated mining machinery2017Ingår i: Mine Planning and Equipment Selection (MPES 2017): Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection Luleå, Sweden, August 29-31, 2017 / [ed] Behzad Ghodrati, Uday Kumar, Håkan Schunnesson, Luleå: Luleå tekniska universitet, 2017, s. 81-86Konferensbidrag (Refereegranskat)
  • 6.
    Qarahasanlou, Ali Nouri
    et al.
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology, .
    Khalokakaie, Reza
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology, .
    Ataei, Mohammad
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology, .
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Operating Environment-Based Availability Importance Measures for Mining Equipment: (Case Study: Sungun Copper Mine)2017Ingår i: Journal of Failure Analysis and Prevention, ISSN 1547-7029, E-ISSN 1864-1245, Vol. 17, nr 1, s. 56-67Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    When a system’s performance is inadequate, the concept of availability importance can be used to improve it. The availability of an item depends on the combined aspects of its reliability and maintainability. In a system consisting of many subsystems, the availability of some subsystems is more important to system performance than others. The availability measure determines the priority of availability across subsystems. Most researchers only consider operation time and ignore the influence of the operating environment; therefore, their estimations are not accurate enough. In contrast to previous research, we focus on the influence of the operating environment on the system/subsystem’s characteristics with a view to prioritizing them based on the importance of availability. The paper considers part of the mining fleet system of Sungun copper mine, including the wagon drill, loader, bulldozer, and dump truck subsystems. We identify an ordered list of possibilities for availability improvement and suggest changes or remedial actions for each item to either reduce its failure rate or reduce the time required to repair it.

  • 7.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, UdayLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.Schunnesson, HåkanLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection: MPES 20172017Proceedings (redaktörskap) (Refereegranskat)
  • 8.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability Analysis of Switches and Crossings: A Case Study in Swedish Railway2017Ingår i: International Journal of Railway Research, ISSN 2361-5376, Vol. 4, nr 1, s. 1-12Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is reported that switches and crossings (S&C) are one of the subsystems that cause the most delays on Swedish Railways while accounting for at least 13% of maintenance costs [6]. It is the main reason why we chose to base our study on this subsystem.

    Intelligent data processing allows understanding the real reliability characteristics of the assets to be maintained. The first objective of this research is to determine the S&C reliability characteristics based on field data collection. Because field failure data are typically strongly censored, an especial statistics software package was developed to process field failure data, as commercial packages have not been found satisfactory in that respect. The resulting software, named RDAT® (Reliability Data Analysis Tool) has been relied upon for this study: it is especially adapted to statistical failure data analysis.

    In the next step the availability of studied switches and crossings is estimated based on the reliability characteristics founded in the first step.

  • 9.
    Javed Rahimdel, Mohammad
    et al.
    Department of Mining Engineering, Sahand University of Technology, Tabriz.
    Mirzaei, Mehdi
    Department of Mechanical Engineering, Sahand University of Technology, Tabriz.
    Hoseinie, Hadi
    Department of Mining Engineering, Isfahan University of Technology.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Whole body vibration assessment of the mining truck drivers: a case study2017Ingår i: Mine Planning and Equipment Selection (MPES 2017): Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection Luleå, Sweden, August 29-31, 2017 / [ed] Behzad Ghodrati, Uday Kumar, Håkan Schunnesson, Luleå: Luleå tekniska universitet, 2017, s. 299-302Konferensbidrag (Refereegranskat)
  • 10.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Comparison of Mine Production Index Factors for Rock Bolter and Shovel2016Ingår i: 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, s. 645-656Konferensbidrag (Refereegranskat)
    Abstract [en]

    MPi uses availability, utilisation and performance to compare and evaluate equipment. These measures apply to all equipment in mining. However equipment use in mining operations could lead to different evaluation of its availability, utilisation and production performance. MPi evaluation and comparison of equipment on MPi basis thus becomes difficult. Shovel and rock bolters are equipment used in open pit and underground mining respectively. Rock bolters are used to place bolts in mining room. Bolts reinforce rock masses through restraining the deformation within the rock masses. In open pit mining shovels are used for loading broken rock in truck for hauling. MPi can be used as scale for comparison of these equipment. However the operational difference between two equipment leads to different evaluation of MPi. Using hypothetical case study difference between availability, utilisation and performance of the rock bolters and shovel is studied. It was found that these parameters must be measured differently for rock bolters than shovel. Rock bolters availability and utilisation should be given less weights consideration as compared to other equipment in continuous mining operation. Its performance measurement it dependent upon bolts installed and capacity of bolts installation rather than tonnage of ore produced. This study can be helpful for evaluating MPi for equipment which are non-continuously used and lacks output in terms of ore tonnage..

  • 11.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Hamedan University of Technology.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lean mining2016Ingår i: The Routledge companion to lean management / [ed] Torbjørn H Netland; Daryl J Powell, New York: Routledge, 2016, s. 302-310Kapitel i bok, del av antologi (Refereegranskat)
  • 12.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Mine production index (MPI)-extension of OEE for bottleneck detection in mining2016Ingår i: International Journal of Mining Science and Technology, ISSN 2095-2686, Vol. 26, nr 5, s. 753-760Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although mining production depends on various equipments, significant amount of production loss can be attributed a specific equipment or fleet. Bottleneck is defined not only by production loss but also by our satisfaction from the equipment. The user satisfaction could be measured as machine effectiveness. Mining literature on performance improvement and optimization of equipment operations assert importance of availability, utilization and production performance as key parameters. These three parameters are useful for evaluating effectiveness of equipment. Mine production index (MPI), which can represent the effect of these factors, has been applied for continuous operation in mining. MPI uses Fuzzy Delphi Analytical Hierarchy Process to determine importance of each three parameter for individual equipment. A case study in a Swedish open pit mine was done to evaluate the field application of MPI. The results reveal that crusher is the bottleneck equipment in studied mine. As a methodical approach, an algorithm which uses MPI and detects bottleneck in continuous mining operation has been proposed.

  • 13.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Production improvement techniques in process industries for adoption in mining: A comparative study2016Ingår i: International Journal of Productivity and Quality Management, ISSN 1746-6474, E-ISSN 1746-6482, Vol. 19, nr 3, s. 366-386Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High profitability and customer satisfaction are of supreme importance for any business. To achieve both objectives, an organisation must design a structured approach. To achieve profitability, organisations look to principles of lean manufacturing and techniques such as EFQM, business excellence. This paper reviews such methodologies across different industries, comparing techniques and elements. Its objective is to determine which methodologies are most applicable to the Swedish mining industry and propose a method to achieve lean mining. To this end, the paper looks at the methodologies of a food manufacturing industry, an automobile component manufacturing company, the manufacturing and service sector, and the oil and gas industry. It finds that the method used in the oil and gas industry is more relevant to mining, even though it has some flaws. Further research is needed to adapt this method to the mining industry.

  • 14.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Railway switches and crossings reliability analysis2016Ingår i: 2016 IEEE International Conference on Industrial Engineering and Engineering Management, 2016, Vol. 2016-December, s. 1412-1416, artikel-id 7798110Konferensbidrag (Refereegranskat)
    Abstract [en]

    Switches and crossings (S&Cs) connect the rail network, guiding trains from one track to another and supporting path crossing. They are critical systems given the frequency of their functional failure and the consequences on the operation, cost and safety of railway transportation. Reliability studies are required to support the transport objective of providing dependable, sustainable and cost effective transportation. The main objective of this study is to assess the reliability characteristics of S&Cs based on field data collection. As field failure data have censored nature, commercial packages have not been satisfactory for processing them; therefore, the study uses a special statistical software package RDAT® (Reliability Data Analysis Tool). The availability of the studied switches and crossings is estimated based on the estimated reliability characteristics. The results show the availability of the S&Cs varies between x and y. This is useful information, as it helps the contractor plan and schedule maintenance. It also helps the asset owner to identify units whose performance is below the desired target and to make replacement decisions.

  • 15.
    Rahimdel, Mohammad Javad
    et al.
    epartment of Mining Engineering, Sahand University of Technology, Tabriz.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ram analysis of rotary drilling machine2016Ingår i: Mining Science, ISSN 2300-9586, Vol. 23, s. 77-89Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rotary drilling machines are the most common machines used for drilling the blast holes in mining and constructions activities. The vital role of drilling operation in mining activities reveals that, the performance analysis of drilling machines and their failure and repair behaviors are essential. There-fore, the present study focuses on the reliability, availability and maintainability (RAM) of drilling ma-chines. In this paper, four rotary drilling machines at Sarcheshmeh Copper Mine in Iran are considered for repair and failure data collection. RAM analysis of drilling machines is done using Markov Approach. Results show that the reliability of drilling fleet is decreased by 0.67% in per hour drilling. The hydraulic system is the main unavailability reason of all machines. Moreover, the most failures of the two newest machines are completely repaired in 25 hours

  • 16.
    Hoseinie, Seyed Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability Centered Maintenance (RCM) for Automated Mining Machinery2016Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Reliability centered maintenance (RCM) was initiated on 1960s in Boeing company to optimize the maintenance process of aircrafts. Since that date, this method has been applied in wide range of industries and has provided a completely positive results and recommendations for implementation in other industries. RCM is a systematic approach to quantitatively assess and optimize the performance of preventive maintenance tasks and to eliminate non-value adding maintenance actions. It provides considerable cost savings due to optimum maintenance effort, increased safety and productivity. This research considers the feasibility of applying the RCM methodology to fully-automated underground mining machineries as one of the vital requirement of early future modern mining. For this purpose, a literature review has been done to clarify the advantages, requirements, issues and challenges of RCM in other industries such as aviation, marine, nuclear, oil and gas, and process industries. It has been tried to analyze the RCM procedure in detailed and to have a look on the adoption issues and requirement for RCM implementation in fully-automated mining. Mainly, in this research, following RCM documents and standards were used for feasibility study: • Classic RCM in Aviation industry (SAE-JA1011, SAE-JA1012)• NASA RCM guidelines • USA’s military standards MIL-STD-2173• International Atomic Energy Agency (IAEA) RCM documentUsing the above mentioned documents, an implementation issues and challenges in developing a RCM program for fully-automated underground mining machineries has been presented. The result of this study shows that RCM is applicable in maintenance planning for fully-automated underground mining machinery. Because, serious safety restrictions are associated with this kind of mining operation and RCM can properly help the engineers to analyze the safety consequences of any failure and make the best decision for maintenance tasks. However, practical application of RCM has some differences in mining context which in this project are discussed in detail. The investigations show the risk priority number is the suitable measure to select the RCM target component/system. Since, there is no operation in site, detective the some evident failures are become impossible in automated mining. Therefore, we have to consider the smartness level and capabilities of agent-based supervisors to get the real feeling of machinery health and operation condition. Internet of Thing platforms are also required in fully automated mine to develop the machine-to-machine communication and to reduce the risk of failures and failure propagation in fleet level. RCM could apply the outcomes of these advanced technologies to optimize the maintenance actions in automated mines.

  • 17.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Uncertainty Analysis of Production in Open Pit Mines: Effect of environmental conditions2016Ingår i: Archives of Mining Sciences, ISSN 0860-7001, E-ISSN 1689-0469Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Production volume by mining equipment is influenced by internal and external parameters. External parameters include weather conditions, human factors etc. This study shows impact of temperature, rainfall and snowfall on production volume achieved under influence of these factors in open pit mine.  The case study is carried out which include data from weather station near an open pit mine and production tonnage. Multi regression modelling in performed using stated factors and production volume.  It was observed that Snowfall and rainfall has impact on production volume. Temperature has no effect on payload achieved as represented by model. With increasing snowfall and rainfall decreases. Higher snowfall (0.8 meter to 1 meter) although has tends to lead higher tonnage compared to low snowfall (0 to 0.8meters). Rainfall causes decrease in production of ore, with increase in rainfall from 1.2 mm, there is sharp decrease in production volume. The optimization table shows that with either no snowfall coupled with maximum rainfall (39 mm) it is possible to achieve production levels of 120 thousand per day. With high snowfall (1.06 metres) and no rainfall, it is possible to achieve maximum of 118 thousand tonnes per day.

  • 18.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Department of Mining Engineering, Hamedan University of Technology, Hamedan.
    Uncertainty Analysis of Production in Open Pit Mines: operational parameter regression analysis of Mining Machinery2016Ingår i: Mining science, ISSN 2353-5423, Vol. 23, s. 147-160, artikel-id msc162312Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In mining uncertainties related to equipment and operation are major reasons for loss of production. In order to address this issue a wide literature review was done in this study. It showed that reliability of equipment, spare part availability, automation of equipment are researched areas focused. However, a methodology which relates operational issues directly to production levels have been not studied with detailed analysis. In order to overcome this issue and propose, a method to achieve production assurance is the objective of this study. A case study with 2.5 years of data from a large open pit mine is carried out. Following the statistical principles, multiple regressions modeling with details analysis, optimization of payload and interpretation of analysis are used. It showed that at system level availability, utilization and maximum capacities are important criteria for finding root cause in loss of production. Model for shovel fleet showed that availability is most important characteristics hindering it to achieve higher level of production. It was also seen that 3 to 4 number of shovels are optimal for achieving current level of production. For truck fleet model represented that capacities involved are less important factor as compared to utilization of fleet.

  • 19.
    Hoseinie, Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hosseini, A.
    Iran Minerals Production and Supply Co., Tabas Parvadeh Coal Company, Tabas.
    Availability analysis of drum shearer machine;: A Case Study2015Ingår i: Proceedings of the 24th International Mining Congress of Turkey, IMCET 2015: Antalya, Turkey, 14- 17 April 2015 / [ed] M. Karadeniz, TMMOB Maden Muhendisleri Odasi , 2015, s. 913-918Konferensbidrag (Refereegranskat)
    Abstract [en]

    Drum shearer plays an important role in the face production in longwall coal mines. Therefore, monitoring of this machine can lead the whole extraction operation to high level of productivity and safety. Availability is one of the most important measures for evaluation of the mining machineries. High availability of equipment can be helpful in satisfying the desired production goals. In this article the availability of drum shearer in an Iranian coal mine has been studied. For this purpose, the failure and maintenance data for a period of two years have been used. After data sorting and analysis, the inherent availability, achieved and operational availability of this machine have been calculated. The results show that the studied shearer machine performs in high level of availability. Nevertheless, the logistics delay time and administrative delays with the share of 25% of whole downtimes are so important influencing factors which should be controlled and planned to minimize it.

  • 20.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hamodi, Hussan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Environmental friendly manufacturing and support: Issues and challenges2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Environmentally Conscious Manufacturing and Product Support (ECMPS) is animportant issue driven by concern for the escalating deterioration of the environment.ECMPS involves integrating environmental thinking into the design of a product, theselection of materials, manufacturing processes, delivery and support to consumers, andend-of-life management of the product after its useful life has ended. Both academia andindustry are interested in finding solutions in this newly emerging research area. Relatedresearch is on pollution prevention, remanufacturing, disassembly, life cycle of products,after sale support and material recovery. The aim of this study is emphasizing the productdesign, operation, maintenance and disassembly effects on environment, and how theseissues can be considered in manufacturing phase to minimize the negative environmentalimpact.

  • 21.
    Hoseinie, Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance planning for drum shearer machine based on its reliability characteristics and economical sensitivity analysis2015Ingår i: Safety and Reliability: Methodology and Applications / [ed] Tomasz Nowakowski; Marek Mlynczak; Anna Jodejko-Pietruczuk ; Sylwia Werbinska-Wojciechowska, London: CRC Press, 2015, s. 1257-1262Konferensbidrag (Refereegranskat)
    Abstract [en]

    Cutting arms are the main productive units of coal shearer machine that contact directly with coal seam. More importantly, the cutting arms operate under a high stress environment. In this paper, in order to suggest an optimum maintenance plan for the subsystem of shearer machine, firstly, we conducted a failure and reliability analysis using the data acquired from the Parvadeh coal mine Iran over the last two years. In doing so, we applied estimated distribution functions and calculated cost parameters to identify the cost-based optimum preventive maintenance interval. The analysis shows that the Power Law Process model provides a good fit to the failure data. Accordingly, the preventive maintenance operation can improve the reliability of the system by 53.5%. Furthermore, we conducted a sensitivity analysis of the studied machine and identified that if we consider the variation of the world price of the raw coal then the maintenance plan is sensitive to the price, however the effects of this change on reliability improvement is almost zero

  • 22.
    Hamodi, Hussan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Al-Gburi, Majid
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Model for economic replacement time of mining production rigs including redundant rig costs2015Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 21, nr 2, s. 207-226Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - This paper presents a practical model to determine the economic replacement time (ERT) of production machines. The objective is to minimise the total cost of capital equipment, where total cost includes acquisition, operating, maintenance costs and costs related to the machine’s downtime. The costs related to the machine’s downtime are represented by the costs of using a redundant machine. Design/methodology/approach - Four years of cost data are collected. Data is analysed, practical optimisation model is developed and regression analysis is done to estimate the drilling rigs ERT. The artificial neural network (ANN) technique is used to identify the effect of factors influencing the ERT of the drilling rigs.Findings - The results show that the redundant rig cost has the largest impact on ERT, followed by acquisition, maintenance and operating costs. The study also finds that increasing redundant costs per hour have a negative effect on ERT, while decreases in other costs have a positive effect. Regression analysis shows a linear relationship between the cost factors and ERT. Practical implications - The proposed approach can be used by the decision maker in determining the economic replacement time of production machines which used in mining industry.Originality/value - The research proposed in this paper provides and develops an optimisation model for economic replacement time of mining machines. This research also identifies and explains the factors that have the largest impact on the production machine’s ERT. This model for estimating the ERT has never been studied on mining drilling rigs.Keywords Decision support model, Life cycle cost, Optimisation, Replacement timePaper type Research paper

  • 23.
    Hoseinie, Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Juuso, Esko
    University of Oulu, Control Engineering Group, Faculty of Technology, University of Oulu.
    Optimal Preventive Maintenance Planning for Water Spray System of Drum Shearer2015Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Water spray system is one of the most important parts of rock cutting machines, especially the drum shearer. Field data shows that the maintenance of this system is time-consuming and causes major downtimes in the coal mines’ production process. Therefore, it is essential to find an optimum preventive maintenance task and intervals, to reduce the downtime and minimize the associated costs of the machine. In this paper, in order to suggest an optimum preventive maintenance plan, a parametric failure and reliability analysis was done on available data from an Iranian longwall coal mine over the two years. A reliability-based cost modelling was implemented to identify the optimum maintenance interval and frequencies of restoration for the water spray system. In the study, a cost rate function was introduced in which an as-good-as-new effectiveness for restoration actions is considered. The results of the analysis showed that the minimum maintenance cost per unit of time for the studied machine, $19.54/hour, will be achieved within a range of intervals i.e. T=136 hours to T=142 hours.

  • 24.
    Ahmadi, Alireza
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Garmabaki, Amir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Optimum inspection interval for hidden functions during extended life2015Ingår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 18, nr 3, s. 45-49Artikel i tidskrift (Refereegranskat)
  • 25.
    Rahimdel, Mohammad Javad
    et al.
    Faculty of Mining Engineering, Sahand University of Technology, Tabriz.
    Sattarvand, Javad
    Faculty of Mining Engineering, Sahand University of Technology, Tabriz.
    Hoseinie, Hadi
    Ghodrati, Behzad
    Practical Approaches to Reduce the Vibration and Health Risk of Operators in Heavy Mining Truc2015Konferensbidrag (Refereegranskat)
  • 26.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Garmabaki, Amir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability considerations in automated mining systems2015Ingår i: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 29, nr 5, s. 404-418Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Automation is the operation of machinery or processes by devices, such as robots and machines, able to make and execute decisions without human intervention. Automation is one of the most attractive research and development areas in mining, as it aims to solve many technical, production and safety problems in current and future mining. This paper studies the structure of automated mining systems from a reliability and failure occurrence perspective. It reviews the main subsystems and related failure modes. Based on field investigation and a literature review, it highlights some critical issues and technical difficulties. Finally, it presents some challenges for future automated mines and offers some related solutions

  • 27.
    Khoshalan, Hasel Amini
    et al.
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology.
    Torabi, Seyed Rahman
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    An introduction to RAM analysis of EPB tunnel boring machine2014Ingår i: Scientific Journal of Pure and Applied Sciences, ISSN 2322-2956, Vol. 3, nr 3, s. 120-127Artikel i tidskrift (Refereegranskat)
  • 28.
    Hamoudeh, Youssef
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Analysis of mine mobile fleet maintenance vs. mine roads maintenance for optimum performance2014Ingår i: Mine Planning and Equipment Selection: Proceedings of the 22nd MPES Conference, Dresden, Germany, 14th – 19th October 2013 / [ed] Carsten Drebenstedt; Raj Singhal, Cham: Encyclopedia of Global Archaeology/Springer Verlag, 2014, Vol. X, s. 1369-1380Konferensbidrag (Refereegranskat)
    Abstract [en]

    The expansion of the mining operations world-wide leads to development of large vehicles. In the past the design of the mine haul roads was done empirically based on the local experience; this way is not applicable anymore because the extreme increase of the truck sizes which demands more focus on mine haul roads quality and performance. The inadequate designs will not only increase the mine haul road maintenance but also will increase the overall operating and maintenance costs of the vehicles. Therefore it is necessary to improve the designs and quality for the mine haul road. The aim of this study is to find out the optimum points which indicate the minimum maintenance cost for both transportation machineries and mine haul roads for both surface and underground mines. The parameters which considered for the transportation machineries are tires consumption, parts vehicles consumption, and labour hour maintenance costs. The major problems in the mine haul roads and vehicles are discussed. The maintenance and rehabilitation of the pavements deterioration are also considered with respects to their costs besides to the minimum accepted values for the pavements performance levels. Consequently, the achievements will comprise minimizing the operation costs, and optimizing the availability and performance/capacity of mobile fleet.

  • 29.
    Hoseinie, Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Assessment of Reliability-Related Measures for Drum Shearer Machine: a Case Study2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Longwall mining is one of the most continuous and productive mining methods. Efficiency of this method is directly affected by the involved machineries and systems. The drum shearer plays an important role in the face productivity and the mine life. Therefore, monitoring of this machine can lead the whole extraction operation to a high level of production and safety. There are several reliability-related measures for evaluation of the mining equipment. Availability, utilization, production efficiency and overall production effectiveness are the most important measure which can help us in this way. In this paper, the production and failure data of a drum shearer machine in Parvade coal mine in Iran have been collected from whole of one longwall panel during a two-year period. The mentioned reliability-related measures have been calculated based on the total uptime and downtime of the machine. The results showed that, the studied drum shearer is in good availability level. However, it has average production efficiency, very low utilization and very low overall equipment effectiveness. Also, high waiting and idling time raises from other machineries during the extraction process, was recognized as the main reason for the current low productivity of shearer machine in mine.

  • 30.
    Hoseinie, Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Cost-effective maintenance scheduling of cutting arms of drum shearer machine2014Ingår i: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, nr 5, s. 297-310Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cutting arms are the main productive units of coal shearer machine that contact directly with coal seam. More importantly, the cutting arms operate under a high-stressed environment. In this paper, in order to suggest an optimum maintenance plan for the subsystem of shearer machine, firstly, we conducted a failure and reliability analysis using the data acquired from the Parvade coal mine, Iran over the two years. The analysis shows that the Power Law Process model provides a good fit to the failure data. Also, we applied estimated distribution functions and calculated cost parameters to identify the cost-based optimum preventive maintenance interval. Furthermore, we conducted a sensitivity analysis of the studied machine and identified that if we consider the variation of the world price of the raw coal then the maintenance plan is sensitive to the price. The analysis showed that, big changes in world price of raw coal are not so effective on maintenance plan but have a considerable effect on maintenance costs of the cutting arms of the shearer machine. However, the effects of this change on reliability improvement are almost zero.

  • 31.
    Hamodi, Hussan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Wijaya, Andi
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Downtime analysis of drilling machines and suggestions for improvements2014Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 4, s. 306-332Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose– The purpose of this paper is to analyse and compare the downtime of four drilling machines used in two underground mines in Sweden. The downtime of these machines was compared to show what problems affect downtime and which strategies should be applied to reduce it.Design/methodology/approach– The study collects failure data from a two-year period for four drilling machines and performs reliability analysis. It also performs downtime analysis utilising a log-log diagram with a confidence interval.Findings– There are notable differences in the downtime of most of the studied components for all machines. The hoses and feeder have relatively high downtime. Depending on their downtime, the significant components can be ranked in three groups. The downtime of the studied components is due to reliability problems. The study suggests the need to improve the reliability of critical components to reduce the downtime of drilling machines.Originality/value– The method of analysing the downtime, identifying dominant factors and the interval estimation for the downtime, has never been studied on drilling machines. The research proposed in this paper provides a general method to link downtime analysis with potential component improvement. To increase the statistical accuracy; four case studies was performed in two different mines with completely different working environment and ore properties. Using the above method showed which components need to be improved and suggestions for improvement was proposed and will be implemented accordingly.

  • 32.
    Hamodi, Hussan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadzadeh, Farzaneh
    Division of Product Realization, Mälardalen University, Eskilstuna.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Economic lifetime prediction of a mining drilling machine using an artificial neural network2014Ingår i: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, nr 5, s. 311-322Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study develops models for predicting the economic lifetime of drilling machines used in mining. It uses three cases, each represented by a MATLAB code, to develop an optimisation model. The resulting ORT is fed as input to an artificial neural network (ANN) and the results translated into a relatively simple equation. The study finds that increasing the purchase price and decreasing the operating and maintenance costs will increase a machine's ORT linearly. Decreased maintenance cost has the largest impact on ORT, followed by increased purchase price and decreased operating cost. The ANN method gives a series of basic weight and response functions which can be made available to any engineer without the use of complicated software. It also helps decision-makers determine the best time economically to replace an old machine with a new one; thus, it can be extended to more general applications in the mining industry

  • 33.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Mine Production index (MPi): New method to evaluate effectiveness of mining machinery2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    OEE has been used in many industries as measure of performance. However due to limitations of original OEE, it has been modified by various researchers. OEE for mining application is special version of classic equation, carries these limitation over. In this paper it has been aimed to modify the OEE for mining application by introducing the weights to the elements of it and termed as Mine Production index (MPi). As a special application of new index MPishovel has been developed by authors. This can be used for evaluating the shovel effectiveness. Based on analysis, utilization followed by performance and availability were ranked in this order. To check the applicability of this index, a case study was done on four electrical and one hydraulic shovel in a Swedish mine. The results shows that MPishovel can evaluate production effectiveness of shovels and determine effectiveness values in optimistic view compared to OEE. MPi with calculation not only give the effectiveness but also can predict which elements should be focused for improving the productivity.

  • 34. Lanke, Amol
    et al.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Mine Production index (MPi): new method to evaluate the effectiveness of mining machinery2014Konferensbidrag (Övrigt vetenskapligt)
  • 35.
    Ahmadi, Alireza
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Garmabaki, Amir Soleimani
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Optimum inspection interval for hidden functions during extended life2014Konferensbidrag (Refereegranskat)
  • 36.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Product Support Logistics Based on System Reliability Characteristics and Operating Environment2014Ingår i: IEEE International Conference on Industrial Engineering and Engineering Management: IEEM 2013, Bangkok, Thailand; 10 - 13 December 2013, Piscataway, NJ: IEEE Communications Society, 2014, s. 457-461, artikel-id 6962453Konferensbidrag (Refereegranskat)
    Abstract [en]

    The environmental conditions in which the equipment is to be operated, such as temperature, humidity, dust, operators’ skill, etc, often have considerable influence directly on the product reliability and indirectly on the product supportability characteristics. This paper, after discussing the factors influencing product reliability, describes a method to estimate spare part requirements based on estimation of the actual reliability of a product under the influence of the product-operating environment using a proportional hazard model. In this research only non-repairable components/parts in repairable systems are studied. Results express a considerable difference between considering and ignoring the operating environmental factor on system performance. So, this factor should be seriously considered while dimensioning product support and service delivery performance strategies, since it will have an impact on operation, maintenance and service quality.

  • 37.
    Hoseinie, Hadi
    et al.
    Hamedan University of Technology.
    Khalokakaie, Reza
    Shahrood University of Technology, Petroleum and Geophysics Department.
    Ataei, Mohammad A.
    Shahrood University of Technology, Petroleum and Geophysics Department.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Monte Carlo reliability simulation of coal shearer machine2013Ingår i: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 9, nr 5, s. 487-494Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper the Kamat-Riley (K-R) event-based Monte Carlo simulation method was used for reliability analysis of longwall shearer machine. Shearer machine consists of six subsystems; water, haulage, electrical, hydraulic, cutting arms and cable systems in a series network configuration. A shearer in the Tabas coal mine was selected as case study and its all failure data were collected and used for reliability analysis of subsystems. With negligible assumption of time to repair, a flowchart was built for programming the simulation process. The Matlab mathematical programming software was used for reliability simulation process. Finally the reliability plot of longwall shearer machine was achieved and upper and lower bound reliability were calculated. The results illustrate that the reliability of shearer machine reduces to zero in a period of 100h. There is a 50% chance that the shearer will not fail for the first 12h of operation.

  • 38.
    Hoseinie, Hadi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Monte Carlo reliaility simulation of water system of longwall shearer machine2013Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 20, nr 6, artikel-id 1350023Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The water system of coal shearer machine consists of three main subsystems namely spray jets, water & hoses, and filters which are connected and working in series configuration. In this paper the Kamat-Riley Monte Carlo simulation method was used for reliability analysis of the considered system. The studied data was collected from an Iranian longwall coal mine for analysis. The MATLAB software was used for simulation and then reliability plot of water system in shearer machine was determined. The results show that the reliability of shearer machine reduces to almost zero in a period of 300h. Comparison between the results of analytical method and simulated reliability plot presents that for analyzed data set, in high reliability levels (28%≤), the simulation approach estimates the higher reliability than analytical method. The maximum difference between the results of analytical and simulation methods is 23%. However, in low reliability levels (≤28%) there is no remarkable difference between the methods.

  • 39.
    Ahmadi, Alireza
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Optimum Failure Finding Inspection During Extended Operation Life2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    In a complex system such as railway and aviation equipment’s, it may be necessary to employ a combination of Failure Finding Inspection (FFI) and a scheduled discard task, as suggested by Reliability-Centered Maintenance (RCM). This strategy ensures an adequate level of availability of hidden functions, as well as the reduction of the risk of multiple failures to an acceptable level. However, in some situations, operators prefer to extend the discard life of components beyond their recommended life limit, due to the operational restrictions. This necessitates the definition of an optimal Failure Finding Inspection interval for the extended life period. This paper aims to provide a mathematical model for defining optimal FFI interval, during the extended period of the replacement life. A cost function (CF) is developed to identify the cost per unit of time associated with different FFI intervals, for the proposed extended period of life, i.e. postponement period. The proposed method concerns as-bad-as-old (ABAO) inspection and repairs (due to failures found by inspection). It considers inspection and repair times, and takes into account the costs associated with inspection and repair, the opportunity cost of lost production due to maintenance downtime created by inspection and repair actions, and also the cost of accidents due to the occurrence of multiple failure

  • 40.
    Lanke, Amol
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reducing defects and achieving business profitability using innovative and lean thinking2013Ingår i: IEEE International Conference on Industrial Engineering and Engineering Management: IEEM 2013, Bangkok, Thailand; 10 - 13 December 2013, Piscataway, NJ: IEEE Communications Society, 2013, s. 1026-1030Konferensbidrag (Refereegranskat)
    Abstract [en]

    The case study conducted in magnet manufacturing shows that with use of innovative thinkingusing TRIZ an organization can achieve the quality ofproduct without sacrificing business goals. Cost of qualityand cost of manufacturing were both balanced with simplesolution to the production problems. Simple innovations leadto increased output capacity and reduction of defects. Thiscontributed to reducing the wastage of resources i.e. achieveLEAN. This case study holds a prime example of TRIZ andhow an manufacturing organization can benefit using such anew technique.

  • 41.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability analysis of switches and crossings: a case study in Swedish railway2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    It is reported that switches and crossings (S&C) are one of the subsystems that cause the most delays on Swedish Railways while accounting for at least 13% of maintenance costs [6]. It is the main reason why we chose to base our study on this subsystem.Intelligent data processing allows understanding the real reliability characteristics of the assets to be maintained. The first objective of this research is to determine the S&C reliability characteristics based on field data collection. Because field failure data are typically strongly censored, an especial statistics software package was developed to process field failure data, as commercial packages have not been found satisfactory in that respect. The resulting software, named RDAT® (Reliability Data Analysis Tool) has been relied upon for this study: it is especially adapted to statistical failure data analysis.In the next step the availability of studied switches and crossings is estimated based on the reliability characteristics founded in the first step.

  • 42.
    Hoseinie, Hadi
    et al.
    Hamedan University of Technology.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability-centered maintenance for spray jets of coal shearer machine2013Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 20, nr 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spray jets constitute one of the most important parts of each type of rock cutting machine, especially the drum shearer. This system cools the cutting picks and controls the dust emission. The blockage of spray jets causes the coal shearer machine to stop automatically. Therefore, the reliable performance of this system assists the achievement of a smooth coal cutting operation. Field's data shows that the maintenance of this system is time-consuming and causes major downtimes in the production process. Therefore, it is essential to find an optimum preventive maintenance task and intervals, to reduce the downtime and minimize the associated costs of the machine. The aim of this paper is to identify an applicable and effective maintenance task, with its associated interval, for management of the failure modes of the spray jets of coal shearers. A case study has been conducted on spray jets of double-drum shearer machine in Tabas Coal Mine in Iran. In the study, the RCM approach is used to select an applicable and effective maintenance task. The failure data were analyzed using a parametric approach to evaluate the reliability of the spray jets, and to estimate the reliability parameters. A reliability-based cost modeling has been implemented to identify the optimum maintenance interval and frequencies of restoration for the spray jets. In the study, a cost rate function (CRF) has been introduced in which an as-good-as-new (AGAN) effectiveness for restoration actions is considered. The CRF also considers restoration and repair times, and takes into account the costs associated with repair and restoration, and the opportunity cost of the equipment's lost production due to maintenance downtime, to arrive at the most cost-effective maintenance intervals. The results of the analysis have shown that the minimum cost per unit of time, $46.5/h, will be achieved within a range of intervals i.e., T = 210 h to T = 260 h.

  • 43.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Spare parts estimation for machine availability improvement addressing its reliability and operating environment: case study2013Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 20, nr 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Industrial operation cost analysis shows that, in general, maintenance represents a significant proportion of the overall operating costs. Therefore, the improvement of maintenance follows the final goal of any company, namely, to maximize profit. This paper studies spare parts availability, an issue of the maintenance process, which is an important way to improve production through increased availability of functional machinery and subsequent minimization of the total production cost. Spare parts estimation based on machine reliability characteristics and operating environment is performed. The study uses an improved statistical-reliability (S-R) approach which incorporates the system/machine operating environment information in systems reliability analysis. For this purpose, two methods of Poisson process and renewal process are introduced and discussed. The renewal process model uses a multiple regression type of analysis based on Cox’s proportional hazards modeling (PHM). The parametric approaches with baseline Weibull hazard functions and time independent covariates are considered, and the influence of operating environment factors on this model is analyzed. The outputs represent a significant difference in the required spare parts estimation when considering or ignoring the influence of the relevant system operating environment. The difference is significant in the sense of spare parts forecasting and inventory management which can enhance the parts and consequently machine availability, leading to economical operation and savings.

  • 44.
    Ahmadi, Alireza
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gupta, Suprakash
    Banaras Hindu University, Varanasi.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Estimation of economic consequences of aircraft system failures2012Ingår i: Communications in Dependability and Quality Management, ISSN 1450-7196, Vol. 15, nr 1, s. 39-49Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large portion of the direct and indirect aircraft operational costs stems from the consequences of decisions made during the maintenance program development. Decision on maintenance task selection for non-safety category of failures, is based on the cost effectiveness, in which the cost of preventive maintenance should be less than the costs associated with the corrective action and failure consequence. Although the assessment of the direct cost for preventive and corrective maintenance is quiet straightforward, however quantification and estimation of the cost associated with the consequence of failure is a great challenge. This is due to a long list of contributory factors and lack of adequate data regarding the cost headings. This study attempts to estimate the economic consequences of aircraft system failures which lead to a technical delay. The paper considers financial losses, mostly due to the additional unexpected costs related to the flight crew, passengers, aircraft itself, ramp and airport, when one of the cost headings, e.g. the pre-fixed crew cost is known. The experience of the field experts has been used following a pairwise comparison technique to compare the cost headings, and to estimate the contribution of each one to the total cost of a delay. The study shows that the proposed model can be a tool to assess the cost of failure consequences in aircraft operation, when there is a limited data and information regarding the cost headings.

  • 45.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Fusion of CMMS Data and CM Data - a real need for maintenance: Part 22012Ingår i: Maintworld, ISSN 1798-7024, E-ISSN 1799-8670, nr 3, s. 40-43Artikel i tidskrift (Övrigt vetenskapligt)
  • 46.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Fusion of CMMS data and CM data: a real need for maintenance (part I)2012Ingår i: Maintworld, ISSN 1798-7024, E-ISSN 1799-8670, nr 2, s. 42-45Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Maintenance can be considered as an information processing system. Therefore, thedevelopment of future maintenance information systems is one of the most importantcurrent research problems to model the effects of automatic condition monitoringsystems enabled by embedded electronics and software.

  • 47.
    Lin, Jing
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Information sharing in a spares demand system2012Ingår i: 2012 IEEE International Technology Management Conference: Dallas,USA, 24 June - 27 June, 2012, Piscataway, MJ: IEEE Communications Society, 2012, s. 36-44Konferensbidrag (Refereegranskat)
    Abstract [en]

    Spare parts inventory management differs from other manufacturing inventory managements mainly due to its speciality in function with maintenance. Furthermore, spares demand management shows more complexities and differs from other productions’ SCM (Supply Chain Management). Recently, studies on information sharing in SCM attract more and more researchers’ attention because of its ability to counter the so-called “bullwhip effect”. Based on the authors’ consultant experiences and studies in practice, information sharing also plays a pivotal role on optimizing the effectiveness of the spares demand system. However, discussions those stand in the point of spares optimization management are limited, which should be a better combination of practical as maintenance engineers and managers making decision support for spares management. Therefore, this paper aims to help them to understand the information sharing in a spares demand system, to illuminate how to optimize the systems’ performance with it, and to elaborate how to improve information sharing process itself. First, a spares demand system was promoted, and information sharing in the system was investigated from a downstream and an upstream process separately. Second, performances of information sharing in such spares demand system were discussed from both qualitative and quantitative viewpoints. Third, the effective ways regarding information sharing utilization to optimize the spares demand system came into question. And finally, how to improve information sharing process in the mentioned system was discussed.

  • 48.
    Ahmadzadeh, Farzaneh
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Mean Residual Life Estimation Considering Operating Environment2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The cost of maintenance of mechanized and automated mining systems is too high necessitating efforts to enhance the effectiveness of maintenance systems and organization. For effective maintenance planning, it is important to have a good understanding of the reliability and availability characteristics of the systems. This is essential for determining the Mean Residual Life (MRL) of systems so that maintenance tasks could be planned effectively. In this paper we used the statistical approach to estimate MRL. A Weibull proportional hazard model (PHM) with time-independent covariates was considered for modelling of the hazard function so that operating environment could be integrated in the reliability analysis. Methods are presented for calculating the conditional reliability function and computing the MRL as a function of the current conditions to guarantee the desired output. The model is verified and validated using data from the Hydraulic system of an LHD fleet from a Swedish mine. The results obtained from the analysis is useful to estimate the remaining useful life of such system which can be subsequently used for effective maintenance planning and help controlling unplanned stoppages of highly mechanized and automated systems.

  • 49.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Banjevic, Dragan
    C-MORE Lab, University of Toronto.
    Jardine, Andrew K.S.
    C-MORE Lab, University of Toronto.
    Product support improvement by considering system operating environment: a case study on spare parts procurement2012Ingår i: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 29, nr 4, s. 436-450Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ongoing availability of existing industrial systems/machines depends to a great extent on the form and level of product support. Product support, or the after sale service of a product, is important because it assures the expected function of the product in its operational phase. Product support is affected by a number of factors, including system reliability and maintainability characteristics and the operating environment. The purpose of this paper is to analyze the influence of time independent external factors of industrial systems on product support requirements and spare parts need.

  • 50.
    Ghodrati, Behzad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Johansson, John
    Sverige.
    Project: CAMM - Lean mining2012Övrigt (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    The current status of Scandinavian mining industry is characterized by semi-autonomous to autonomous and intelligent production machines. Since many of these autonomous machines are expected to perform round the clock, the importance of system characteristics such as reliability, availability, flexibility and controllability are of prime importance. Other area is focused on seamless integration of information to realize the vision of autonomous mining system and been actively developing and implementing the concept of collaborative and intelligent operation and maintenance for operating systems. Therefore, the vision of a Digital Mine with autonomous mining systems seems a possibility especially with the advent of new and emerging technologies together with willingness of mining industry to make investment towards semi autonomous and autonomous mining systems.For achieving lean production, all the processes and systems need to communicate in real time so as to eliminate uncertainty and address the critical issues and challenges often arising at short notices in a continuously changing environment as found in mining operations.The plan for research development intends to take the mining industry several steps forward in creating a reliable robust and productive autonomous mining system. Our goal is to build a state of the art research capability in the area of mine production system by working on the following subproject addressing the critical issues to realise the vision of lean mining system.Work plan A: Improvement of production availability and delivery assuranceWork plan B:Rock and machine interfaceWork plan C:Remaining useful life of mining systemsWork plan D:Integration of mine work environment into production systems

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