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  • 151.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Wayside Condition Monitoring Technologies for Railway Systems2014Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The railway is an important mode of transport, due to its environmental friendliness, high safety level, and low energy consumption, among other reasons. Railways provide a sustainable means of transporting a large amount of freight and passengers, in a cost-effective and comfortable way. The railway system has a large number of stakeholders and a small improvement in the system will give many advantages, including financial savings and an increase in the quality of service. The Swedish railway network is old and there has been almost no expansion of the network during the past few decades. There is currently a demand for more track capacity and there are no more tracks availably at the network; therefore, the existing network is expected to deliver more capacity.The railway operators are the largest cause of train delays and wheel failures are one major contributor of the delays caused by operators. The infrastructure manager is the second largest owner of train delays, and a large contributor of their train delays is switches and crossings (S&Cs). This thesis shows proposals for how condition monitoring technology can be used more efficiently for both the infrastructure and the rolling stock to increase the reliability of their critical items by decreasing train delay. Firstly, the condition of the wheel-rail interface is important, in that a bad wheel influences the rail and vice versa. The monitoring of rail profiles is already in use, but the monitoring of wheel profiles is still in the development phase. This thesis shows the performance of a wheel profile measurement system (WPMS) for an extreme climate, and a case study of performance measures such as the accuracy and reliability of the system is presented. An additional topic dealt with is how the information from the WPMS can be combined with that from the wheel defect detectors to find early indications of wheels with bad behaviour. Secondly, the S&C is an essential component of a railway system in that it increases the flexibility by diverting traffic, but S&Cs need adequate support to work properly. A camera-monitoring method for S&Cs is presented which increases the inspection frequency and decreases the human activities on the track and the train delay. In conclusion, this thesis shows that the WPMS investigated works well with a high level of performance concerning measurement accuracy and reliability in an extreme climate, and that there is still some potential for improving the system. The combination of the WPMS and wheel defect detectors shows that wheels with a high flange height have a higher probability of ending up as wheels suffering from failures. A new maintenance limit for the flange height can reduce the number of wheel defects on the track. Camera-monitoring of the S&C will increase the availability and reliability of this item and even reduce the time on the track required for the maintenance action “check” through fewer inspections and maintenance actions. These proposed monitoring techniques can improve the railway system reliability by reducing the consequential train delay times, by decreasing the number of failures of wheels and S&Cs.

  • 152.
    Asplund, Matthias
    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.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Condition monitoring and e-maintenance solution of railway wheels2014Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 3, s. 216-232Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose – The purpose of this paper is to investigate the failure-driven capacity consumption of wheels on the track, to determine whether there are some relations to vehicle wheel configurations that show a larger amount of failures, and to ascertain the influence of the temperature and the travelling direction of the train on the number of events. This information can be used to develop prognostic health management (PHM) so that more track capacity can be gained without modifications, re-building or re-investments. Design/methodology/approach – This paper presents a study of 1,509 warning and alarm events concerning train wheels. The data come from the infrastructure manager’s wheel defect detectors and wheel profile measurement system. These data have been analysed and processed to find patterns and connections to different vehicles, travelling directions and temperatures. Findings – Lower temperatures increase the probability of wheels having high vertical forces. Trains with different wheel configurations show different results. With high vertical forces, the probability of wheel failures at axle 6 and 7 is high for locomotives with two bogies and three axles in each bogie (2x3). All these findings can be used to develop the maintenance, monitoring and inspection principles for wheels. Practical implications – The inspection of wheels to detect failures needs to be more frequent on days and in seasons with lower temperatures. The wheel inspection should be performed more frequently at axle 6 and 7 for locomotives with a 2x3 wheel configuration. The inspection and monitoring of wheels need to be carried out more carefully for trains travelling south, to avoid a large amount of wheels with high force levels rolling in the southern direction. Originality/value – The analysis carried out in this paper identifies important factors that correlate with the high occurrence of wheel defects. It also proposes a conceptual e-maintenance model for the combination of wheel condition monitoring data from different system. The value of this study is the provision of information to support prognostic and health management system to support proactive maintenance.

  • 153.
    Asplund, Matthias
    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.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Data quality assessment of automatic wheel profile measurement systems2016Ingår 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. 717-738Konferensbidrag (Refereegranskat)
    Abstract [en]

    The aim of this paper is to present a method for the quality assessment of data from a condition monitoring system for rolling stock wheels to ascertain if the data have the right quality to be used for further analyses. This quality assessment will also show if there are variations between different measurement units for the same system, and if there are relations between different wheel parameter measurements, speed and time. The assessment of data is accomplished using the quality dimension freedom of error. There are two different data sources, namely an automatic wheel profile measurement system and a manual wheel profile measurement device. The manual measurements of wheel profiles are used for verifying the accuracy of the automatic wheel profile measurements, which constitute the larger data set. The proposed method for evaluating the data quality is demonstrated using the data from a specific condition monitoring system. The results show some inconsistencies indicating that this system lacks quality in the dimension of freedom of error and that there is need for internal calibration or self-adjustment of the studied system for quality reasons.

  • 154.
    Asplund, Matthias
    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.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Prognostic and health management of wheel condition: integration of wheel defect detection and wheel profile monitoring data2012Ingår i: Proceedings of the 2nd International Workshop & Congress on eMaintenance: Dec 12-14 Luleå, Sweden : eMaintenace: trends in technologies and methodologies, challenges, possibilities and application / [ed] Ramin Karim; Adyita Parida; Uday Kumar, Luleå: Luleå tekniska universitet, 2012, s. 15-22Konferensbidrag (Refereegranskat)
  • 155.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. The Swedish Transport Administration, Trafikverket.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Schoech, Wolfgang
    3Speno International, Meyrin, Switzerland.
    A Nordic heavy haul experience and best practices2017Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 231, nr 7, s. 794-804Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article summarizes the experiences gained at the Nordic heavy haul line “Malmbanan” located in Northern Sweden and Norway during the years 2007 to 2015 and the resulting best practice. Unique long-term information of field trials and monitoring from the on-going development for maintenance of rail and wheel has been described. The reported results come from the rail profile measurements using MiniProf and HC-recordings with Eddy-current devices and visual inspection on 43 test sections. The monitoring has been continuous since the project started, to reveal a deep insight into the complex wheel–rail interaction and provide understanding of the effect of applying optimized specifications. This was particularly important in view of the increasing traffic load that contributed to doubling of the yearly grinding campaigns. This article presents in particular the new MB5 profile, the wear rate behaviour between two different curves, impacts of gauge widening on rail rolling contact fatigue and the speed of gauge widening as well as the seasonal impact on the crack propagation. The presently applied maintenance strategy is discussed together with other experiences. The article finishes with some conclusions and an outlook into further work.

  • 156.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gustafsson, Per
    SWECO Energuide AB.
    Nordmark, Thomas
    LKAB.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Palo, Mikael
    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.
    Wandt, Karina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability and measurement accuracy of a condition monitoring system in an extreme climate: a case study of automatic laser scanning of wheel profiles2014Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 228, nr 6, s. 695-704Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Iron Ore Line (Malmbanan) is a 473 km long track section located in northern Sweden and has been in operation since 1903. This track section stretches through two countries, namely Sweden and Norway, and the main part of the track runs on the Swedish side, where the owner is the Swedish Government and the infrastructure manager is Trafikverket (the Swedish Transport Administration). The ore trains are owned and managed by the freight operator and mining company LKAB. Due to the high axle load exerted by transportation of the iron ore, 30 tonnes, and the high demand for a constant flow of ore and pellets, the track and wagons must be monitored and maintained on a regular basis. The condition of the wagon wheel is one of the most important aspects in this connection, and here the wheel profile plays an important role. For this reason an automatic laser-based wheel profile monitoring system (WPMS) has been installed on this line using a system lifecycle approach that is based on the reliability, availability, maintainability and safety (RAMS) approach for railways. The system was prepared and installed and is being operated in a collaborative project between the freight operator and infrastructure manager. The measurements are used to diagnose the condition of the wheels, and to further optimize their maintenance. This paper presents a study of the concepts and ideas of the WPMS, and the selection, installation and validation of the equipment using a system lifecycle approach that is based on RAMS for railways. Results from the profile measurements and validation are shown. The system’s reliability during performance in extreme climate conditions, with severe cold and large quantities of snow, is presented. Then the benefits, perceived challenges and acquired knowledge of the system are discussed, and an improved V-model for the lifecycle approach is presented.

  • 157.
    Asplund, Matthias
    et al.
    Swedish Transport Administration, Trafikverket Luleå.
    Khan, Saad Ahmed
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Improved wheel-rail system of Sweden’s iron ore line2017Ingår i: Proceedings of the 11th International Heavy Haul Association Conference (IHHA 2017), Cape Town, South Africa, 2–6 September 2017 / [ed] P.J. (Hannes) Gräbe, R.D. Fröhling, 2017, s. 759-766Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    ABSTRACT: The Swedish Iron Ore Line (IOL) is the only heavy haul line in Europe. The northern part of the line is located above the Arctic Circle, a very harsh climate. Because of the introduction of new vehicles with a 30-tonnes axle load, the track were gradually replaced between 2006 and 2009 with heavier rails, mostly with a steel grade of R350LHT. Just after the first replacement of track in 2006, the project presented herein was established with the primary goal of improving the life length of the rail, and monitoring activities started. This project now has a unique database of rail degradation data. So far, the information has been used to improve the performance of the wheel-rail system and thus extend the life length of the rail, as well as to improve our knowledge of heavy haul operations in a cold climate. The paper discusses the project progress in general and gives some examples of improvements that have been successfully implemented, such as new rail profiles and a higher grinding frequency. Finally, it discusses the challenges of future capacity improvements, such as an increase in the axle load, and how these can be addressed.

  • 158.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Larsson, Dan
    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.
    Nissen, Arne
    Trafikverket.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Inspection of railway turnouts using camera2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    The railway turnout is an essential component in a railway system, used to divert traffic along different tracks. A turnout includes a number of different parts, including the switch blade, frog, point machine, switch roller, soleplate, check rail, wing rail, drive rods, control rods and other bars. These parts must be kept in good condition, meeting functional and safety requirements. Failing to comply will result in a reduction of the network’s capacity with economic consequences. Not honouring the safety limits could result in severe accidents, including derailment, causing human casualties. By performing the right type of inspection and/or maintenance at the right time, these unwanted events can be reduced. To determine if and when a maintenance action should be performed, the condition of the turnout must be established, usually by manual inspections or with measurement vehicles. The drawback is the discrete nature of these inspection events. Failure modes with development times shorter than the inspection interval could result in a malfunction of the unit. An on-line measurement system would be able to deal with these failure events and initiate correct maintenance actions at an earlier stage. With an on-line system, remotely located turnouts could be inspected without on-site personnel. Capacity consuming failures of turnouts with a strategic location or with bottleneck characteristics could also be corrected before they affect traffic. This paper describes a feasibility study of a camera based inspection system for turnouts and discusses the effect the method could have on system reliability and capacity.

  • 159.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Janet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Evaluating the measurement capability of a wheel profile measurement system by using GR&R2016Ingår i: Measurement, ISSN 0263-2241, E-ISSN 1873-412X, Vol. 92, s. 19-27Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reliable data with less variation play a key role for acceptance of the usefulness of the measurement output of a wheel profile measurement system (WPMS) in a railway network. However, in practice, most studies are carried out without checking the reliability of data from such a system, which may lead to inappropriate maintenance strategies. To ensure the measurement capability of WPMS and to support robust maintenance in railway systems, this study has evaluated measurement data for the flange height, flange thickness, flange slope, and tread hollowing of rolling stock wheels by using gauge repeatability and reproducibility (GR&R). In this study, acceptance and rejection criteria for the precision-to-tolerance ratio (PTR), signal-to-noise ratio (SNR), and discrimination ratio (DR) have been employed to evaluate the measurement capabilities. For the purpose of illustration, we have implemented a new proposed approach. This approach involves both an analysis using graphs with four regions with a confidence interval (CI) of 95% and an analysis using a graph with three regions with only the predicted values; the latter type of graph represents an innovation made in this study. The results show that the measurements of the tread hollowing and flange slope are on an acceptable level, while those for the flange height and flange thickness have to be rejected as unacceptable. The action proposed to increase the quality of data on the flange height and flange thickness is to enhance the calibration of the WPMS. In conclusion, GR&R is a useful tool to evaluate the measurement capability of WPMS and to provide helpful support for maintenance decision making.

  • 160.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Janet
    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.
    Assessment of the data quality of wayside wheel profile measurements2016Ingår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 19, nr 3, s. 19-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To evaluate the behaviour and the condition of a railway wheel in relation to performance and safety criteria, the wheel profile can be measured. This can be achieved using manual methods or automatic systems mounted along the railway track. Such systems have the advantage that they can measure a vast number of profiles, enabling new possibilities of performing statistical analyses of the results and pinpointing bad wheels at an early stage. These wayside measurement systems are, however, subjected to different environmental conditions that can affect the data quality of the measurement. If one is to be able to use automatic wheel profile measurements, the data quality has to be controlled in order to facilitate maintenance decisions. This paper proposes a method for the data quality assessment of an automatic wayside condition monitoring system measuring railway rolling stock wheels. The purpose of the assessment method proposed in this paper is to validate individual wheel profile measurements to ensure the accuracy of the wheel profile measurement data and hence the following data analysis. The method consists of a check routine based on the paired t-test, which uses a hypothesis test to verify if the null hypotheses are true. The check routine compares measurements of passing wheels rolling to a certain destination with measurements of the same wheels returning from that destination. The routine of comparing measurements of the same wheel, which is performed by four sensors (one on each side of each rail), will ensure that the sensors generate the same data for the same sample. A case study is presented which shows how the method can detect a faulty setup of the measurement system and prevent incorrect interpretations of the data from different measurement units in the same system. The paper ends with a discussion and conclusions concerning the improvements that are presented.

  • 161.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Janet
    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.
    Enhancing the quality of data from a wheel profile measurement system: a proposed approach2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    This investigation proposes a method for increasing the quality of data from an automatic condition monitoring system for railway rolling stock wheels, in order to assure the right data quality for further use of the data. The data quality improvement is used to ensure a higher reliability of the data analysis and to propose a new check routine to ensure that the sensors generate the same data for the same sample. A case study on field data shows how the data from different measurement setups differ for three of four measurements and why this check routine is needed. The paper ends with a discussion and conclusions concerning the improvements that are presented.

  • 162.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gustafsson, Per
    Comparison of TOR lubrication systems on the iron ore line2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    The Iron Ore Line (IOL) is a 473 km long track section which is located in northern Sweden and northern Norway, and has been in operation since 1903. The northern part is located above the Arctic Circle. The IOL is mainly used to transport iron ore and pellets from the mines in Kiruna and Malmberget to Narvik Harbour (Norway) in the northwest and Luleå Harbour (Sweden) in the southeast. The track section on the Swedish side is owned by the Swedish Government and managed by Trafikverket (the Swedish Transport Administration), while the ore wagons are owned and managed by the freight operator (LKAB).The IOL has seen a considerable increase in the axle load and traffic volume recently. Due to the introduction of new vehicles with a 30-ton axle load, the rails were gradually replaced between 2006 and 2009 with heavier rails, generally with a steel grade of 350LHT. The rail and wheels suffer from rolling contact fatigue (RCF) due to high friction between the rail and wheel. To control the wheel-rail interface, wayside top-of-rail (TOR) lubrication can be used. The reliability of the TOR lubrication equipment and the lubricants in northern conditions has not been investigated, and the long-term maintenance support required for TOR lubrication is unknown to the infrastructure manager. Furthermore, can TOR lubrication reduce the rail and wheel maintenance costs? This project has been conducted through collaboration between the main operator (LKAB) and the infrastructure manager (Trafikverket); the costs have been shared and the results analysed in collaboration. This paper describes the test period of two years, using two different TOR lubrication systems in two different places on the IOL, one situated in the northern loop and one in the southern loop, each with different operational conditions. The paper shows the actual operational conditions for the pilot test locations, the friction value close to the systems, the rail forces during the test period and some results for the noise measurements. Furthermore, the paper includes the improvements of system resulting from the test operation, and ends with recommendations for the continued use of TOR lubrication on the IOL.

  • 163.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gustafsson, Per
    Pallari, Robert
    Mining Technology R and D, LKAB Kiruna Mine.
    Larsson, Dan
    Damill AB, Luleå, Damill AB.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Slutrapport avseende hjulprofilmätare i Sunderbyn2014Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Bakgrunden till projektets genomförande har varit den ökande mängden rälsbyten och mängden trafik med 30 tons axellast på Malmbanan. Spårunderhållet och hjulunderhållet har idag de överlägset högsta underhållskostnaderna av järnvägens olika system. Hjulprofilmätaren sågs som en möjlighet att kunna plocka ut de hjul som närmade sig underhållsgränserna för slitage, och därigenom kunna styra underhållet mer kostnadseffektivt.LKAB och Trafikverket enades därför att sätta upp ett gemensamt projekt där en ny typ av mätutrustning utprovades. För att få stöd med datalagring, bearbetning av data mm anlitades LTU och eMaintenanceLAB. Syftet med projektet har varit att undersöka och verifiera att en utrustning för automatisk hjulprofilmätning kan klara av att registrera och larma vid hjulpassager som avviker från de säkerhetsgränser och underhållsgränser som definieras i projektet med hänsyn till vårt klimat och våra förhållanden på Malmbanan. Den bärande idén i detta projekt har varit att man genom en kontinuerlig mätning av hjulprofiler ska kunna ta ut fordon ur trafik innan den avvikande hjulprofilen ger upphov till ett accelererande hjul- och rälslitage och därigenom sänka underhållskostnaden och öka livslängden på både hjul och räl. Projektet har även lett till en högre säkerhet på spåret då man kan mäta hjul som passerat säkerhetsgränsen för hjulparametrar och plockar bort dem, detta var inte var möjligt tidigare. De slutsatser som kan dras från detta projekt är följande:• Utvecklingsprojekt kan med fördel genomföras gemensamt mellan industri, infrastrukturförvaltare och akademi. • För att säkerställa ett bra resultat är det viktigt att genomföra alla steg i ett projekt från koncept till överlämnande. Som stöd för detta har V-modellen används som representerar livscykeln för systemet enligt EN-50126.• Val av tekniklösning och leverantör har gjorts utifrån tekniknivå, referensanläggningar samt drift- och supportmöjlighet och inte enbart utifrån pris. Ett utvecklingsprojekt likt detta handlar inte primärt om att få en utrustning i drift utan överföring av ”know how” kring vilka möjligheter och begränsningar det finns med denna teknik.• Resursbehovet för test och utvärdering underskattades och gjorde att projektet försenades ett år jämfört med ursprunglig tidplan. • Informationen som genereras från denna utrustning är mycket användbar för alla parter som arbetar med utveckling av underhåll inom järnvägen. • Utmaningen för att tillgodogöra sig nyttan från mätstationen ligger i att kunna förädla och integrera de genererade tillståndsdata till respektive underhållsorganisation.

  • 164.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Pallari, Robert
    Mining Technology R and D, LKAB Kiruna Mine.
    Gustafsson, Per
    Mining Technology R and D, LKAB Kiruna Mine.
    Larsson, Dan
    Damill AB, Luleå, Damill AB.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    The wheel profile measurement system at Sunderbyn, Sweden: final report2014Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The background to the realisation of this project comprises an increasing number of rail replacements and an increasing volume of traffic with a 30-tonne axle load on the Swedish Iron Ore Line (IOL). When comparing the maintenance costs of all the different systems in the Swedish railway network, the maintenance costs for the track and wheels are by far the highest at present. The wheel profile measurement system (WPMS) was considered to provide the possibility of picking out wheels approaching the maintenance limits for wear and thereby of controlling maintenance in a more cost-effective way. Accordingly, LKAB and Trafikverket (the Swedish Transport Administration) reached an agreement concerning the initiation of a joint project in which a new type of measurement equipment would be tested. To obtain assistance with data storage and processing, etc., Luleå University of Technology (LTU) and its eMaintenance Lab were engaged in the project. The objective of the project has been to investigate and verify whether equipment for automatic wheel profile measurement is capable of registering wheel data and sending alerts concerning the passage of wheels which deviate from the safety and maintenance limits defined in the project, with regard to the climate and conditions prevailing along the Swedish IOL. The fundamental idea behind this project has been that, through continuous measurement of wheel profiles, one should be able to take vehicles out of service before any deviating wheel profiles give rise to accelerating wheel and rail wear, and that one should thereby be able to reduce the maintenance costs and increase the operational life of both wheels and rails. An additional result of the project has been increased safety on the track, since it is possible to measure wheels that have exceeded the safety limit for wheel parameters and remove them, which was impossible previously. The following conclusions can be drawn from this project.• There are benefits to be derived from development projects conducted jointly between industry, infrastructure managers and academia. • In order to ensure good results, it is important to perform all the steps in a project, from the concept phase to the handing-over phase. In support of this, the V-model was used, which represents the life cycle of the system according to EN 50126. • The selection of a technical solution and a supplier was made on the basis of the technology level, reference installations, and operation and support possibilities, and not merely based on the price. A development project of this nature is not primarily a question of putting equipment into operation, but of transferring knowhow concerning the possibilities and limitations associated with the technology in question. • The resource requirement for testing and evaluation was underestimated, which resulted in the project being delayed by one year compared with the original timetable. • The information generated by the equipment installed is very useful for all parties working with the development of railway maintenance. • The challenge with regard to utilising the benefits afforded by the measurement station at Sunderby lies in the ability to process the generated condition data for the maintenance organisations concerned and integrate these data in the operations of these organisations.

  • 165.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Palo, Mikael
    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.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A study of railway wheel profile parameters used as indicators of an increased risk of wheel defects2016Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 230, nr 2, s. 323-334Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The capacity demands on the railways will increase in the future, as well as the demands for a robust and available system. The availability of the railway system is dependent on the condition of the infrastructure and the rolling stock. To inspect the rolling stock and to prevent damage to the track due to faulty wheels, infrastructure managers normally install wayside monitoring systems along the track. Such systems indicate, for example, wheels that fall outside the defined safety limits and have to be removed from service to prevent further damage to the track. Due to the nature of many wayside monitoring systems, which only monitor vehicles at definite points along the track, damage may be induced on the track prior to fault detection at the location of the system. Such damage can entail capacity-consuming speed reductions and manual track inspections before the track can be opened for traffic again. The number of wheel defects must therefore be kept to a minimum. In this paper wheel profile parameters measured by a wayside wheel profile measurement system, installed along the Swedish Iron Ore Line, are examined and related to warning and alarm indications from a wheel defect detector installed on the same line. The study shows that an increased wheel wear, detectable by changes in the wheel profile parameters could be used to reduce the risk of capacity-consuming wheel defect failure events and its reactive measures.

  • 166.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Palo, Mikael
    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.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Condition monitoring of rolling stock wheels: approach towards maintenance decision making2014Ingår i: 27th International Congress on Condition Monitoring and Diagnostic Engineering (COMADEM 2014): 16 - 18 September 2014, Brisbane Convention and Exhibition Centre, Australia, COMADEM International, 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Due to the more or less fixed inherent capacity of a railway system, capacity consuming events like failures within a railway network should be kept to a minimum. This could be achieved by the use of existing and new condition monitoring systems which can detect, report and predict failure events in an early stage. Demands for higher service quality, higher capacity, network availability and track quality together with less human intervention on tracks, drive the development of railway condition monitoring systems.Failure driven capacity consumption due to worn or defected rolling stock wheels have a big impact on the capacity and the infrastructure condition. Wheel defects such as out-of-round wheels, generates high forces, and could result in large capacity consumption especially for areas with cold climate conditions. Bad wheels cause even higher track wear that reduce the life length of the track. Wheels with fatigue defects could also influence the track safety issues. This paper presents how different wheel defects can be monitored; together with a review of the most common wayside condition monitoring systems on the Swedish railway network. The study also describes how the decision making process could take advantage of the condition monitoring data in order to increase the achieved network capacity.

  • 167.
    Asplund, Matthias
    et al.
    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.
    Evaluation of wheel profile measurements by means of the contact-point function for the wheel-rail interface2018Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 232, nr 4, s. 1225-1239Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study examines the accuracy of a wayside train wheel profile measurement system. This was accomplished by an evaluation of the contact-point function for the wheel–rail interface. The wheel profile measurement system in question generates data about the wheel profiles of passing trains. These data are used for improving the wheel maintenance procedures for the rolling stock operator. Recent work shows that there are differences between the data from the two different units in the system, but how this influences further use of the data, e.g. in wheel–rail contact analysis, has not been investigated so far. Accordingly, this article shows how two key wheel measures (the wheel flange thickness and the wheel profile) impact on the contact-point function and which of these measures has the largest impact on the contact-point function. The data used in this study were generated by two different measurement units for the same wheel and with the same wheel status. The results show that the different units produce different results and that these differences are more prominent when a difference in the flange thickness is detected, with a resulting shift of the front side of the flange and of the tread. With no difference in the flange thickness, i.e. no shift of the front side of the flange and of the tread, a difference was still detected in the contact conditions. Furthermore, this investigation shows that the shape of the tread has a greater impact on the contact-point conditions compared to a change in the flange thickness of up to 2.5 mm. This difference in the tread shape could have originated in measurement noise or different wheel measurement positions. The results of the study also show the importance of managing the measurement quality before using the data, for example for maintenance decisions.

  • 168.
    Asplund, Matthias
    et al.
    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.
    Johnsson, Roger
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hiensch, Martin
    Combating curve squeal noise2016Ingår i: Combating curve squeal noise, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Society demand for more sustainable transports is increasing, starting a modal shift from road to railway. The resulting increase in railway traffic intensity is leading to more activities on the track, even during the night time. For many years continuous urbanization has been resulting in a higher density of residents in areas close to railway tracks. The combination of these factors is raising the issue of noise disturbances from railway transports, which is forcing infrastructure managers to take action to combat noise from railway traffic systematically. There are different types of noise emanating from railways and one of the most annoying is curve squeal noise. This paper deals with the curve squeal phenomenon, the places where it occurs, and different methods for reducing it. The curving behaviour of a vehicle plays an important role in the generation of curve squeals, and therefore the way in which different rail profiles affect the capability to steer in a sharp curve is dealt within this paper. The paper is based on two case studies with investigated curves in urban regions that suffer from squeal noise, and in which comparisons between measurements and simulations were performed. The outcome of these studies is a workflow for combating squeal noise, results concerning the effects of a top-of-rail friction modifier on noise mitigation, and a proposed rail profiles for improving the steering capability of vehicles.

  • 169.
    Asplund, Matthias
    et al.
    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.
    Palo, Mikael
    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.
    Wandt, Karina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nordmark, Thomas
    LKAB.
    Gustafsson, Per
    SWECO.
    Automatic laser scanning of wheel profiles: condition monitoring to achieve greater capacity for existing infrastructure in an extreme climate2013Ingår i: Automatic laser scanning of wheel profiles: condition monitoring to achieve greater capacity for existing infrastructure in an extreme climate, India: Indian Railways, the host of 10th IHHA Conferance , 2013, s. 445-451Konferensbidrag (Refereegranskat)
    Abstract [en]

    The Iron Ore Line (Malmbanan) is a 473 km long track section located in northern Sweden and has been in operation since 1903. It is mainly used to transport iron ore and pellets from the mines in Kiruna and Malmberget to Narvik Harbour (Norway) in the northwest and Luleå Harbour (Sweden) in the southeast. The track section on the Swedish side is owned by the Swedish Government and managed by Trafikverket (the Swedish Transport Administration), while the ore wagons are owned and managed by the freight operator (LKAB). Due to the high axle load exerted by the iron ore transports, 30 tonnes, and the high demand for a constant ore/pellets flow, the track and wagons must be monitored and maintained on a regular basis. The condition of the wagon wheel profile is one of the most important aspects in this procedure. For this reason an automatic laser-based wheel profile monitoring system has been installed on this line. This system can automatically measure and monitor the wagon wheel profiles at speeds up to 130 km/h. The system was installed and is being operated in a collaboration project between the freight operator and infrastructure manager. The information generated is collected by the e-maintenance personnel at Luleå Railway Research Center (JVTC). The measurements will be used to diagnose the condition of the wheel and rail, and to optimize their maintenance further. This paper presents a study of the selection and the installation of the equipment. Some results from the measurements are shown. The system’s availability during performance in extreme climate conditions, with severe cold and large quantities of snow, is presented. Then the benefits and perceived challenges of the system are discussed. Some potential improvements in rail and wheel maintenance, to achieve more capacity, are analysed.

  • 170.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Schoech, Wolfgang
    Speno International.
    Towards perfected rail maintenance: combining routine and long-term research activities2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    In 2007 the new grinding strategy with “Malmbanan”, Europe’s only heavy-haul railway, has been presented at the IHHA-conference in Kiruna. Four years later an update was given, as in between some adaptations concerning the target profiles and the metal removal requirements have been introduced. The monitoring process on selected test sections using MiniProf- and Eddy-current devices never stopped and provided since valuable understanding of the effect of applying optimized specifications. This was particular important in view of the increasing traffic load and the hence required doubling of the yearly grinding campaigns. The combination of the once fixed routine grinding operations with the research activities resulted in a consistently good rail surface situation and revealed further insight in the complex matter of wheel-rail interaction. The latest findings and further development is presented in this article.

  • 171.
    Astrand, M.
    et al.
    ABB Corp Res, Control Optimizat & Analyt, Automat Solut, Västerås, KTH Royal Inst Technol.
    Johansson, M.
    KTH Royal Inst Technol.
    Greberg, Jenny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Underground mine scheduling modelled as a flow shop: a review of relevant work and future challenges2018Ingår i: Journal of the southern African institute of mining and metallurgy, ISSN 2225-6253, Vol. 118, nr 12, s. 1265-1276Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Advanced planning and automation are increasingly important in modern mines. Sophisticated methods for long-term mine planning are often used, and the advent of autonomous machines makes the actual operation more predictable. However, the interface between these two timescales, i.e. the scheduling of the mobile production fleet, often limits the ability to operate mines at maximum profitability. We show how scheduling the production fleet in an underground mine can be modelled as a flow shop. A flow shop is a general abstract process formulation that captures the key properties of a scheduling problem without going into specific details. Thus, the flow shop enables mine scheduling to reap the benefits of scheduling research from other industries. We review recent results from the mining community and the flow shop community, and introduce scheduling methods used in these two fields. This work aims at providing value to researchers from the mining community who want to leverage their skill set, as well as to theoretical researchers by presenting the mining process as a potential application area. Lastly, we discuss the results, and outline some future challenges and opportunities facing the industry.

  • 172.
    Ataei, Mohammad A.
    et al.
    Shahrood University of Technology, Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology.
    Mikaeil, Reza
    Department of Mining and Metallurgy Engineering, Urmia University of Technology, Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technolog.
    Hoseinie, Hadi
    Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technolog.
    Hosseini, Seyed Mehdi
    Department of Mining, Shahrood Branch, Islamic Azad University, Shahrood.
    Fuzzy analytical hierarchy process approach for ranking the sawability of carbonate rock2012Ingår i: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 50, s. 83-93Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new classification system is presented to evaluate and ranking the sawability of carbonate rock. The sawability of carbonate rock is classified into five categories: excellent, good, fair, poor and very poor. The sawability is assumed to depend on the uniaxial compressive strength, Young's modulus, Mohs hardness, and a new abrasivity index. The FAHP approach is used to determine the weights of the above-mentioned parameters by decision makers. Moreover, in this paper, a new classification system was developed to modify Schimazek's F-abrasiveness factor. In this new abrasivity classification, each parameter has a different importance coefficient. The new abrasivity index of carbonate rocks can be obtained from this new abrasivity classification system. The calculated sawability index of developed classification is applied for Iranian carbonate rocks to evaluation the energy consumption in rock sawing process. A variety of two groups of carbonate rocks (seven types) were saw using a fully instrumented laboratory sawing rig at different feed rates, peripheral speeds, and depth of cut. Then, a new statistical model was obtained using multiple regression method based on operating parameters and rock sawability index

  • 173.
    Backlund, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Akersten, Per-Anders
    RCM introduction: process and requirements management aspects2003Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 9, nr 3, s. 250-264Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organisations have introduced reliability-centred maintenance (RCM) with a view to changing their overall way of performing maintenance. Many times, however, these organisations have experienced cumbersome or even failed RCM introduction. This is usually because of managerial and organisational obstacles, which more or less unexpectedly turn up during introduction. This paper focuses on managing the introduction of RCM. By applying process and requirement management principles, obstacles that turn up during introduction can be identified early on. As an example of this, we cite the results of a case study of the introduction of RCM in a Swedish hydropower company.

  • 174.
    Backlund, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Hannu, J.
    Luleå tekniska universitet.
    Can we make maintenance decisions on risk analysis results?2002Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 8, nr 1, s. 77-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For several branches of industry, an increasingly competitive environment has raised important questions concerning maintenance in plant systems. For example, the 1996 deregulation in Sweden's electricity sector has resulted in increased competition among the country's power producers. To survive the competition, suppliers have to reduce maintenance costs, i.e. handle maintenance more efficiently. Risk analysis is one tool decision makers can use to help them prioritise as they plan maintenance actions. There are a number of different approaches to risk analysis. As the results of an analysis must form a reliable basis for decision making, it is important to consider whether the quality of the results will vary significantly with the risk analysis approach chosen. This paper presents a comparative study based on three independent risk analyses performed on a specific hydro-power plant. The comparison and evaluation of the analyses reveal major differences in performance and results, along with various factors that affect the quality of the analyses. The study establishes the importance of a well-planned requirement specification and the need to analyse and interpret risk analysis results, before making maintenance decisions.

  • 175.
    Backlund, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Holmberg, Rikard
    Vattenfall Vattenkraft.
    Söderholm, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A 10 years journey introducing RCM within hydropower: a case study at Vattenfall Vattenkraft2008Ingår i: EuroMaintenance Papers: Conference and Trade Show on Asset Management & Production Reliability ; Brussels Expo, 8 - 10 April 2008, Belgian Maintenance Association , 2008, s. 21:1-21:10Konferensbidrag (Refereegranskat)
  • 176.
    Backlund, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Larsson, Dan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Rhen, Mats
    Luleå tekniska universitet.
    Risk analysis and condition monitoring for efficient maintenance planning at Swedish hydro power plants1998Ingår i: Safety and reliability: proceedings of the European Conference on Safety and Reliability, ESREL '98, Trondheim, Norway, 16 - 19 June 1998 / [ed] Stian Lydersen, Amsterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1998, s. 247-253Konferensbidrag (Refereegranskat)
    Abstract [en]

    Maintenance issues have in recent years grown in importance. Higher demands on availability and quality of products are some of the reasons. These demands have resulted in an increased use of condition monitoring systems, to support an effective maintenance concept. For a complex system, this technique generates an enormous amount of signals which is difficult to diagnose, and a great amount of information which is difficult to handle and interpret for the operator. Therefore, improved diagnosis and decision support tools are necessary, as a complement to the monitoring systems. This paper presents an ongoing project, trying to find a new approach to condition monitor and diagnose Kaplan hydro-power turbines, where the chain from transducer to decision making is under consideration. Risk analysis is adequate for decision making among alternative maintenance tasks and the ambition is a risk model that can be systematically updated with varying economic data and production requirements. Also, the availability is under consideration for the hydro power plant, as a total system, where the owners of the plant should be able to steer the availability according to demand. Another important aspect is the possibility of the condition monitoring system to test itself, which will prevent false alarms.

  • 177.
    Baglee, David
    et al.
    Institute for Automotive Manufacturing and Advanced Practices, University of Sunderland, Department of Computing, Engineering and Technology, Institute for Automotive and Manufacturing Advanced Practise, University of Sunderland, School of Computing and Technology, University of Sunderland.
    Knowles, Michael
    Institute for Automotive Manufacturing and Advanced Practices, University of Sunderland, University of Sunderland.
    Kinnunen, Sini Kaisu
    School of Business and Management, Lappeenranta University of Technology.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A proposed maintenance strategy for a wind turbine gearbox using condition monitoring techniques2016Ingår i: International Journal of Process Management and Benchmarking, ISSN 1460-6739, E-ISSN 1741-816X, Vol. 6, nr 3, s. 386-403Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Renewable energy sources such as wind are available without limitations, but reliability is critical if pay back periods are to be met. The current reliability and failure modes of offshore wind turbines are known and have been used to develop preventive and corrective maintenance strategies but have done little to improve reliability. The analysis of gear lubricants can detect early signs of failure. Reliability centred maintenance (RCM) approach offers considerable benefit to the management of wind turbine operation, as it includes an appreciation of the impact of faults. This paper provides an overview of the application of RCM and condition monitoring techniques, to support the development of a maintenance strategy. It discusses the development of a sensor-based processing unit that can continuously monitor the lubricated systems and provide, real-time data enabling onshore staff to predict degradation anticipate problems and take remedial action before damage and failure occur

  • 178.
    Baglee, David
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Knowles, Michael
    University of Sunderland.
    Morris, Adrian
    University of Sunderland.
    O´Hagan, Geraldine
    Glenmorangie Company.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Optimisation of food and engineering supply chain technology (OPTFEST): a case study2013Ingår i: International Congress of Condition Monitoring and Diagnostic Engineering Management: Comadem 2013 / [ed] Antti Heijo, Helsinki: KP-Media Oy Messuaukio 1 00520 Helsinki Finland , 2013, s. 498-503Konferensbidrag (Refereegranskat)
    Abstract [en]

    Predictive maintenance attempts to detect theonset of a degradation mechanism with thegoal of correcting that degradation prior tosignificant deterioration in the component orequipment. The diagnostic capabilities ofpredictive maintenance technologies haveincreased in recent years. The advances insensor technologies, component sensitivities,size reductions, and most importantly, cost,has allowed manufacturing processes,especially where once this technology was‘missing’, the opportunity to enter a new andnecessary area of diagnostics. One area inparticular is the food and drink industry.However, with the introduction of any newtechnology, proper application and training isof critical importance. In addition, theimplementation of any new maintenancestrategy should be supported by a welldeveloped information system. This paper willpresent the development and implementation,through case study analysis, of a newmaintenance strategy using predictivemaintenance strategies and an informationsystem designed to support staff training. Thisproject has resulted in the transfer of modernmaintenance technologies, alreadysuccessfully implemented in other industrysectors to the food processing sector. This hasbeen achieved through the transfer andimplementation of structured maintenancemethods and the introduction of monitoringtools for processing equipment. Significantbenefits include the ability to predict equipmentfailure, the development of best practice andcompliance with supplier audits. Theinformation interchange systems developed inthe project allow both users and suppliers todevelop and improve engineering andmaintenance guidelines, thus enabling theuser to improve plant and production efficiencyand determine the correct mix of technologies.

  • 179.
    Balindres, Anecito Reyes
    et al.
    University of Stavanger.
    Kumar, Rupesh
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Markeset, Tore
    Centre for Industrial Asset Management, University of Stavanger, School of Science and Technology, Stavanger University College, Tromsø University, Center for Safe Operation in HIGH North, University of Tromsø.
    Effects of Arctic Conditions on Human Performance2016Ingår i: Advances in Physical Ergonomics and Human Factors: Proceedings of the AHFE 2016 International Conference on Physical Ergonomics and Human Factors, July 27-31, 2016, Walt Disney World®, Florida, USA / [ed] Ravindra Goonetilleke; Waldemar Karwowski, London: Encyclopedia of Global Archaeology/Springer Verlag, 2016, s. 657-663Konferensbidrag (Refereegranskat)
    Abstract [en]

    Modern technologies are used to create competitive performance in industry, and highly specialized personnel are often needed to operate and maintain the technology. However, both the technology and the personnel are influenced by the environment in which the technologies are operated. In this paper we study how human performance is influenced by an Arctic environment in conjunction with a remote location. Based on a literature study, we map Arctic factors and study how they affect human performance in remote locations. The results show that operational and maintenance personnel may be significantly affected by the Arctic conditions. If not taken into consideration during the design phase, human and organizational performance may be significantly affected. Examples are discussed in relation to petroleum production in Arctic locations north of Norway

  • 180.
    Banda, Sraj U.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rock Mass Characterization of the Printzsköld and Fabian Orebodies at the Malmberget Mine2013Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Rock mass characterization is usually the first practice required when investigating rock mass responses in mining areas. The ground surface in the Malmberget mine has been affected by subsidence and formation of sinkholes, which have affected many residential areas. As mining progresses to lower levels, caving is expected to occur in the cap rocks of the Printzsköld and Fabian. For optimal planning and operations in the mine, it is therefore necessary to understand the caving mechanism of this area and to investigate the controlling factors in the deformations. This report is a summary of a preliminary rock mass characterization of the Malmberget Mine area, which was aimed at investigating rock mass parameters that will help in the understanding of the caving mechanisms. Diamond core drilling was conducted to obtain rock core for logging. Rock core logging was conducted as well as borehole photography, in which various rock joint orientations were determined. Rock core investigations also revealed zones of weakness due to various phenomena such as weathering, shearing, etc. Laboratory testing of the core samples revealed strength isotropy and high rock mass quality in many areas along the boreholes. Tunnel mapping was carried out only on two production levels of 945 and 970 meters of the Printzsköld orebody. The rock mass has been characterized using the Bieniawski 1989 system of Rock Mass Classification (RMR). The Geological Strength Index was also used to characterize the rock mass in the areas where tunnel mapping took place.

  • 181.
    Barabadi, A.
    et al.
    Iran Itok, Engineering, Procurement and General Contracting.
    Barabady, Javad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Slope stability analysis using probabilistic method: a case study2008Ingår i: 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, s. 887-896Konferensbidrag (Refereegranskat)
  • 182.
    Barabadi, Abbas
    et al.
    University of Tromsø - The Arctic University of Norway.
    Garmabaki, Amir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. Islamic Azad University.
    Fuqing, Yuan
    Tromsø University.
    Lu, J.
    University of Tromsø - The Arctic University of Norway.
    Maintainability analysis of equipment using point process models2015Ingår i: 2015 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM): Singapore, 6-9 Dec. 2015, Piscataway, NJ: IEEE Communications Society, 2015, s. 797-801, artikel-id 7385757Konferensbidrag (Refereegranskat)
    Abstract [en]

    The maintenance cost can be reduced significantly by applying the maintainability principle in the design and operation phase. An effective maintainability prediction can help the designer to improve performance and safety of equipment. The analysis of historical repair by an affective statistical approach provides essential information for decision-making regarding the planning of operation and maintenance activities of the plant. However, the literature on field repair data is quite scarce and they are not detailed. This paper will try to provide step by step guideline for field repair data using point process models by a case study.

  • 183.
    Barabadi, Abbas
    et al.
    Tromsø University, Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Garmabaki, Amir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Zaki, Rezgar
    Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Designing for performability: An icing risk index for Arctic Offshore2016Ingår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 124, s. 77-86Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ice accretion affects the performability of offshore production facilities in various ways, including repair time and failure rate. It can increase power losses, life cycle costs and safety hazards. There are few studies and limited systematically collected information about the impact of ice accretion on performability and its attributes (reliability, maintainability, quality, safety and sustainability) for Arctic offshore production facilities. This paper will discuss the effects of different types of ice accretion on the performability of Arctic offshore production facilities. Then, to quantify their effect on the performability of offshore production facilities, an icing risk index is developed; its application is then shown by means of a case study.

  • 184.
    Barabadi, Abbas
    et al.
    Tromsø University.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Barabady, Javad
    Tromsø University.
    Markeset, Tore
    University of Stavanger.
    Reliability and spare parts estimation considering operational environments: a case study2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Spare parts provision is a complex problem andrequires an accurate model to analysis all factors that mayaffect the required number of spare parts. The number ofspare parts required can be effectively estimated based onthe reliability performance of the item. The reliabilitycharacteristics of an item are influenced not only by theoperating time, but also by factors such as the operationalenvironment. Therefore, for spare parts provisioning to beeffective, the impact of these influence factors on thereliability performance of the item should be quantified.Hence, the statistical approach selected for reliabilityperformance analysis must be able to handle the effect ofthese factors. One of the important models for reliabilityperformance analysis that takes influence factors intoaccount is the proportional hazard model (PHM), which hasreceived less attention in the field of spare partsprovisioning. In this paper the application of PHM to spareparts provision is discussed and demonstrated by a casestudy.

  • 185.
    Barabady, Javad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Improvement of system availability using reliability and maintainability analysis2005Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    System reliability, maintainability and availability have assumed great significance in recent years due to a competitive environment and overall operating and production costs. Performance of equipment depends on reliability and availability of the equipment used, operating environment, maintenance efficiency, operation process and technical expertise of operators, etc. When the reliability and availability of system are low, efforts are needed to improve them by reducing the failure rate or increasing the repair rate for each component or subsystem. The aim of this research study is to analyse operating reliability and availability for a system with periodically inspected and maintained components subjected to some maintenance strategy and find some importance measures that show the criticality of the components or subsystems. This analysis has helped to identify the critical and sensitive subsystems or components of the system that need more attention for improvement. In this research study we suggest a methodology for improving the availability of a repairable system. In the methodology, the concept of importance measures must be used to prioritize the components or subsystems for availability improvement processes. Availability importance measures show the criticality of each component based on different points of view such as availability, repair rate, and failure rate of each component. The reliability and availability of repairable systems can be improved by applying appropriate maintenance strategies; therefore a model is developed for selecting the most suitable maintenance strategies on based of analysis of reliability and maintainability characteristic of the operating system. The empirical data of two crushing plants at the Jajarm bauxite mine of Iran are used as a case study for reliability and availability analysis. The study shows that the reliability and maintainability analysis is very useful for deciding maintenance intervals, planning and organizing maintenance. The results show that availability and reliability importance measures can be used as a guideline for managing the efforts for reliability and availability improvement of a system.

  • 186.
    Barabady, Javad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Production assurance: concept, implementation and improvement2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The dynamic business environment is characterized by short-term and long- term uncertainties in the business processes, combined with a short-term focus on meeting customers' and share-holders' requirements. Therefore, making correct decisions in a dynamic business environ-ment is a major challenge for production plant engineers and managers all over the world. Such a situation necessitates the successful application of tools and engineering solutions to minimize the total business risk and reduce uncertainties through assurance of world-class production plant performance, which can ensure that the right level of production can be ob- tained in order to meet customer demands. To meet these challenges, many approaches such as reliability analysis techniques have proved an effective solution during both design and operation of a production plant, and have been implemented by production engineers and managers. The main focus of reliability is on the process of ensuring a reliable product and/or system as well as reducing system uncer- tainty. However, these are not discussing the issues of production availability which are criti-cal for meeting customer requirements and market demands and may increase risk and uncer-tainties in decision-making. However, production assurance (PA) plays a significant role in supporting the decision-making process by production managers and engineers deal with the above mentioned challenges. The main focus of existing research on the area of PA is on the models and methodologies for data analysis and prediction of future system performance. Fur-thermore, existing models and methodologies supporting PA analysis and management have been primarily developed for the planning phases, specifically for the petroleum sector, but have not yet been sufficiently developed for general use. In many cases, the engineers and managers may face many problems in the process of implementing and executing the PA con-cept. The purpose of this research is to study, analyze and evaluate the application and implementa-tion of Production Assurance Programs (PAP) in production plants, and find some importance measures that show the criticality of the components or subsystems. To fulfill the stated pur- pose, an explorative literature study combined with a case study of a process plant has been performed. Various examples and data from the oil and gas industry are also used to support the thesis. In this study, firstly the concept of production assurance is discussed and Overall Production Assurance Effectiveness (OPaE) is suggested as a developed metrics for measuring the per-formance of a production plant which is considered internal effectiveness of production plant as well as external effectiveness as it considered customer requirement and demand. This thesis present and discusses a methodology that facilitates implementation of PAPs in a production plant. Such a methodology would support production engineers and managers in reducing or eliminating uncertainties and risks in their day to day operation and maintenance decisions. In this research study, some availability importance measures are defined. Thereafter, it a methodology is suggested to improve the production assurance effectiveness through im-provement of reliability, maintainability, and availability of production plant. In the method-ology, the concept of importance measures is used to prioritize the components or subsystems. This analysis of importance measures has helped to identify the critical and sensitive subsys-tems or components that need more attention for improvement. The research study shows that in order to measure the performance of a production plant, the PA provides a more comprehensive measure of a production plant's real performance com-pared to system availability performance as the production assurance provides information about the production plant's delivery capacity, production rate and ability to deliver according to design or customer demands. The study also indicates that availability importance measures can serve as a guideline for developing a strategy for improvement of production assurance.

  • 187.
    Barabady, Javad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability and maintainability analysis of crushing plants in Jajarm bauxite mine of Iran2005Ingår i: 2005 proceedings: Annual Reliability and Maintainability Symposium, International Symposium on Product Quality and Integrity : Alexandria, Virginia, USA, 2005, January 24 - 27, Piscataway, NJ: IEEE Communications Society, 2005, s. 109-115Konferensbidrag (Refereegranskat)
    Abstract [en]

    Reliability is an important consideration in the planning, design and operation of engineering systems. As the size and complexity of mining equipment continue to increase, the implications of equipment failure become ever more critical. An unplanned failure can result in significantly higher repair costs than a planned maintenance or repair. Of even more importance is the loss of production associated with larger equipment failures. One method to mitigate the impact of failures is to improve the reliability of the equipment. Reliability is a performance indicator of overall equipment condition. A first step in reliability improvement is collection and analysis of the appropriate data.This paper presents a case study describing reliability analysis of crushing plants in Jajarm bauxite mine. In this study crushing plants are divided into seven subsystems. Reliability analysis has been done for each subsystem by using failures data. The parameters of some idealized probability distributions, such as Weibull, Exponential, Lognormal distributions, have been estimated by using ReliaSoft's Weibull++ 6 software. An investigation has also been made to determine which of these distributions provide the best fit for characterizing the failure pattern of the two crushing plants and their subsystems. Some aspects of system failure behavior are analyzed briefly for ongoing machine improvement. Reliability of both crushing plants and its subsystems has been estimated at different mission times with their best fit distribution. Analysis of the total downtime, breakdown frequency, reliability, and maintainability characteristics of different subsystems shows that the reliability of crushing plant 1 and crushing plant 2 after 10 hour reduce to about 64% and 35% respectively. The study shows that reliability and maintainability analysis is very useful for deciding maintenance intervals. It is also useful for planning and organizing maintenance.

  • 188.
    Barabady, Javad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Aven, T.
    University of Stavanger.
    A methodology for the implementation of production assurance programmes in production plants2008Ingår i: Journal of Risk and Reliability, ISSN 1748-006X, E-ISSN 1748-0078, Vol. 222, nr 3, s. 283-290Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is an increased use of production assurance programmes in various industries, especially in the petroleum sector. The programme describes the production assurance activities necessary to fulfil the objectives, how they will be carried out, by whom, and when. The activities provide input to decisions regarding concept, design, manufacturing, construction, installation, operation, and maintenance. However, production assurance programmes have not yet been sufficiently developed for general use. It is a challenge to implement and apply such programmes in a practical setting. There is a lack of implementation guidelines. The purpose of the current paper is to meet these challenges; the paper describes and discusses a methodology that facilitates implementation of production assurance programmes in a production plant. The starting point is the offshore oil and gas industry, but the methodology and discussion are to a large extent general and could also be applied in other industries.

  • 189.
    Barabady, Javad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Aven, Terje
    University of Stavanger.
    Implementation of production availability programmes in engineering projects2007Ingår i: Risk, Reliability and Societal Safety: proceedings of the European Safety and Reliability Conference 2007 (ESREL 2007), Stavanger, Norway, 25 - 27 June 2007 / [ed] Terje Aven; Jan Erik Vinnem, London: Taylor and Francis Group , 2007, s. 487-494Konferensbidrag (Refereegranskat)
    Abstract [en]

    The aim of this paper is to present and discuss a methodology for implementing production availability programmes in engineering projects. The programmes are to ensure that the project goals will be met. The programme describes the production availability activities necessary to fulfil the objectives, how they will be carried out, by whom and when. The activities provide input to decisions regarding concept, design, manufacturing, construction, installation, operation and maintenance. The proposed methodology consists of three primary tasks and decisions. The three primary tasks are i) establish production availability requirements; ii) provide input to the design process and to operations; and iii) monitor production availability achievement and publish periodic report. Establishing the proposed methodology will help ensure that the project has a cohesive and cost-effective production availability programme, reflecting a production availability process and activities defined in view of the actual needs, available personnel resources, budget framework, interfaces, milestones, and access to data and general information.

  • 190. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A method for managing the availability improvement efforts2006Ingår i: Engineering Asset Management: Proceedings of the First World Congress on Engineering Asset Management (WCEAM), London: Encyclopedia of Global Archaeology/Springer Verlag, 2006, s. 445-451Konferensbidrag (Refereegranskat)
    Abstract [en]

    Availability is an important characteristic of a repairable system. When the availability of system is low, efforts are needed to improve it. Any improvement in the availability of a system is associated with the requirement of additional effort and cost. Therefore, it is essential to use methods or techniques for availability allocation amongst various components/subsystems of a system with the minimum effort and cost. The concept of importance measures could be used to prioritize the components or subsystems for the availability improvement process. The study shows, it is useful to obtain the availability importance measures value of each component in the system prior to deploying resources towards improving the specific components. With the assistance of importance measures one can identify the components/subsystems that merit additional research and development to improve their availabilities, so that the greatest gain is achieved in the system availability. Each component should be assigned a value and the component with a greater value will have a greater influence on the availability of the system. Generally, the importance of components should be used during the design or evaluation of systems to determine which components or subsystems have the greatest importance for the availability of the system.

  • 191. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Availability alocation through importance measures2007Ingår i: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 24, nr 6, s. 643-657Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - To define availability importance measures in order to calculate the criticality of each component or subsystem from availability point of view and also to demonstrate the application of such importance measures for achieving optimal resource allocation to arrive at the best possible availability. Design/methodology/approach - In this study the availability importance measures of a component are defined as a partial derivative of the system availability with respect to the component availability, failure rate, and repair rate. Analyses of these measures for a crushing plant are performed and the results are presented. Furthermore, a methodology aimed at improving the availability of a system using the concept of importance measures is identified and demonstrated by use of a numerical example.Findings - The availability importance measure of a component/subsystem is an index which shows how far an individual component contributes to the overall system availability. The research study indicates that the availability importance measures could be applied in developing a strategy for availability improvement. The subsystem/component with the largest value of importance measure has the greatest effect on the system availability. Research limitations/implications -The result of availability improvement strategy is demonstrated using only a hypothetical example.Practical implications - Using of availability importance measures will help managers and engineers to identify weaknesses and indicate modifications which will improve the system availability.Originality/value - This paper presents the concept of availability importance measure for a component/subsystem. It also introduces some availability importance measures based on failure rate, mean time between failures (MTBF), and repair rate/mean time to repair (MTTR) of a component /subsystem. The concept of importance measures are used to prioritize the components or subsystems for the availability improvement process.

  • 192. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance schedule by using reliability analysis: a case study at Jajarm bauxite mine of Iran2005Ingår i: 20th World Mining Congress, November 7-11, 2005, Tehran, Iran: mining and sustainable development, Teheran: Geological Survey of Iran , 2005Konferensbidrag (Refereegranskat)
    Abstract [en]

    Maintenance represents a significant proportion of the overall operating costs in the mining industry. The optimal maintenance scheduling can reduce the cost of maintenance and extend equipment lifetime. Since the cost of maintenance is very high, therefore, mining industry need to reduce maintenance cost reasonably meanwhile keeping system reliability and availability high. Despite the large cost of maintenance, mine management has only given passing attention to the optimization of the maintenance process. Performance of a mine production system depends on reliability and effectiveness of maintenance strategy of the equipment. An unplanned failure can result in significantly higher repair costs than a planned maintenance or repair. Of even more important is the loss of production associated with larger equipment failures. This paper is divided into two parts. First part introduces a methodology for optimal maintenance scheduling using reliability analysis and maintenance data analysis, in the form of time between failure and time to repair distributions. In the second part we present a case study from Jajarm bauxite mine of Iran to illustrate the effectiveness of the maintenance scheduling model.

  • 193. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Production assurance concept for a mine production system2008Ingår i: Mine planning and equipment selection: proceedings of seventeenth International Symposium on Mine Planning and Equipment Selection (MPES 2008), held in Beijing, China October 20-22, 2008 / [ed] Raj K Singhal, Bejing: Conference Division, Metallurgical Council of CCPIT , 2008, s. 379-387Konferensbidrag (Refereegranskat)
  • 194. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability analysis of mining equipment: a case study of a crushing plant at Jajarm Bauxite Mine in Iran2008Ingår i: Reliability Engineering & System Safety, ISSN 0951-8320, E-ISSN 1879-0836, Vol. 93, nr 4, s. 647-653Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The performance of mining machines depends on the reliability of the equipment used, the operating environment, the maintenance efficiency, the operation process, the technical expertise of the miners, etc. As the size and complexity of mining equipments continue to increase, the implications of equipment failure become ever more critical. Therefore, reliability analysis is required to identify the bottlenecks in the system and to find the components or subsystems with low reliability for a given designed performance. It is important to select a suitable method for data collection as well as for reliability analysis. This paper presents a case study describing reliability and availability analysis of the crushing plant number 3 at Jajarm Bauxite Mine in Iran. In this study, the crushing plant number 3 is divided into six subsystems. The parameters of some probability distributions, such as Weibull, Exponential, and Lognormal distributions have been estimated by using ReliaSoft's Weibull++6 software. The results of the analysis show that the conveyer subsystem and secondary screen subsystem are critical from a reliability point of view, and the secondary crusher subsystem and conveyer subsystem are critical from an availability point of view. The study also shows that the reliability analysis is very useful for deciding maintenance intervals.

  • 195. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability charecteristic based maintenance scheduling: a case study of a crushing plant2007Ingår i: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 3, nr 3, s. 319-328Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The cost of maintenance is too high in mining industry to ignore. This is mainly due to poor understanding of the maintenance process which is greatly influenced by the reliability characteristics of the operating system. The paper introduces an approach for maintenance scheduling of a mining system based on reliability analysis which is divided into two parts. The first part introduces a methodology for optimal maintenance scheduling based on analysis of maintenance data in the form of time-between-failure and time-to-repair distributions. In the second part, we present a case study from Jajarm Bauxite Mine in Iran to illustrate the applicability of the maintenance scheduling model.

  • 196. Barabady, Javad
    et al.
    Markeset, T.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Overall production assurance effectiveness2008Ingår i: Proceedings of the 3rd World Congress on Engineering Asset Management and Intelligent Maintenance Systems: WCEAM-IMS 2008 : Engineering Asset Management - A Foundation for Sustainable Development, 27 - 30 October 2008, Beijing, China, 2008, s. 202-206Konferensbidrag (Refereegranskat)
  • 197. Barabady, Javad
    et al.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A framework for improvement of production plant performance using production assurance programs2010Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 1, nr 1, s. 59-65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The main objective of a production assurance program (PAP) for a production plant is to ensure that the planned production capacity is achieved. The assurance programs describe the activities necessary to fulfil the objectives, how they will be carried out, by whom, and when. These activities also provide input to decisions-making regarding design, manufacturing, construction, installation, operation, and maintenance of plants. It is a challenge to manage and improve production assurance. The aim of this paper is to present and discuss a methodology for improvement of production assurance performance through PAP, organized into four steps, namely data collection and information management, modeling and data analysis, generation of improvement alternatives and evaluation and decision-making.

  • 198. Barabady, Javad
    et al.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Improvement of production plant performance using production assurance programs2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    There is an increased use of production assurance programmes in Oil and Gas industries. The programme describes the production assurance activities necessary to fulfill the objectives, how they will be carried out, by whom and when. The activities provide input to decisions regarding concept, design, manufacturing, construction, installation, operation and maintenance. It is a challenge to manage and improve production assurance. The aim of this paper is to present and discuss a methodology for improvement of production assurance performance. The proposed methodology consists of four steps. These steps are i) data collection and information management; ii) modeling and data analysis; and iii) generate improvement alternatives; and iv) evaluation alternatives and decision making.

  • 199. Barabady, Javad
    et al.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Review and discussion of production assurance program2010Ingår i: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 27, nr 6, s. 702-720Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - The purpose of this paper is to review, discuss and further develop the production assurance (PA) concept; and to define and describe a typical production assurance program (PAP) and its elements. Design/methodology/approach - An explorative literature study covering PA and dependability concept was carried out on contemporary literature. During the course of the study, meetings and discussions with a number of experts in Sweden and Norway were performed. Different types of data and examples from the oil and gas industries are used to illustrate and support the discussions. Findings - This paper indicates that the concept of PA helps the decision maker to estimate whether a production plant is able to meet customer requirements, as it provides information about the production plant's delivery capacity, production rate and ability to deliver according to design or customer demands. PAP can provide a basis for effective production control. Research limitations/implications - The material analysed was mainly related to the oil and gas industry. However, the findings and discussion can be transferred to other areas of application, such as mine production plants and chemical process plants. Practical implications - A PAP is a valuable tool for production plant managers and engineers, not only for documenting a production plant's performance, but also for providing decision support for the development and optimization of the production plant to improve the plant's performance and reduce risk and uncertainties. Originality/value - In this paper the concept of dependability is extended to include capacity performance and customer requirements or market demand, which provides a measure for delivery assurance or plant production performance in relation to customer requirements. This paper also develops a generic PAP to achieve a high level of delivery assurance.

  • 200.
    Barba, Tomas Villegas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Numerical analyses of the hangingwall failure due to sublevel caving: study case2013Ingår i: International Journal of Mining and Mineral Engineering, ISSN 1754-890X, E-ISSN 1754-8918, Vol. 4, nr 3, s. 201-223Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The sublevel caving used in Kiirunavaara mine induces failure and subsidence of the hangingwall. Two sections of the mine were studied by means of numerical analyses. Numerical models were developed using finite element and discrete element codes. The former was applied to calculate the location of new failure surfaces in the hangingwall and to estimate the break angle when mining advances downwards. The latter was used to analyse the displacement path of the caved rock during draw and to determine its effect on the stability of the hangingwall and footwall. The models were calibrated using displacement monitoring data. The finite element analyses indicated that the break angle is almost constant for deeper mining levels but may change if the geometry of the orebody changes. The discrete element model showed the formation of a stationary zone along the footwall that reduces the magnitude of the shear forces during draw, increasing its stability.

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