Conference PaperPDF Available

Simulation-Based Optimization of Maintenance Crew Configuration in Mining Sites

Authors:

Abstract

The mining sector is a production industry that requires the efficient and interactive use of limited resources such as human resources, proven reserves, and equipment fleets. Mining companies must establish a delicate balance among these resources with the aim of achieving maximum productivity and efficiency. One of the most critical departments of a mining operation is the maintenance and repair department responsible for performing and planning maintenance and repair activities to ensure the operational reliability and reliability of the equipment fleet. These departments require human resources with different technical competencies and specialties. The number of personnel with different qualifications required for a maintenance and repair department is influenced by factors such as the equipment used in the relevant mining operation, the failure modes they are exposed to, the frequencies at which these failures occur, and the subsequent repair times. Uncertainties such as failure frequencies, repair times, and the number of employees assigned to failure modes often exist at different levels, and in situations where uncertainty increases, cases of maintenance and repair not being carried out due to a shortage of personnel are frequently observed. Employing an excessive number of personnel in the field allows maintenance and repair activities to be carried out on time but also leads to high physical expenses. This situation creates a trade-off point between production losses and physical expenses that need to be optimized when it comes to the shortage or excess of maintenance and repair personnel. The current research aims to create a simulation model that takes into account different equipment and failure mode behaviors in a working mining area and attempts to optimize the required maintenance and repair personnel numbers in different specialties accordingly. Thus, the model aims to allocate the necessary personnel to different equipment failure modes to achieve maximum efficiency and performance.
SIMULATION-BASEDOPTIMIZATIONOFMAINTENANCECREWCONFIGURATIONIN
MININGSITES
MADENSAHALARINDABAKIM-ONARIMEKİBİYAPILANDIRMASININSİMÜLASYONTABANLI
OPTİMİZASYONU
S.F.Sahiner
,*
,O.Golbasi
1
1
MiddleEastTechnicalUniversity,MiningEngineeringDepartment
(*CorrespondingAuthor:fsahiner@metu.edu.tr)
ÖZ
Madencilik sektörü, insan kaynağı, kanıtlanmış rezerv ve ekipman filosu gibi kısıtlı kaynakların
verimliveetkileşimliolarakkullanılmasınıgerektirenbirüretimsektörüdür.Madencilikşirketleri,maksimum
üretkenlikveverimliliğisağlamakamacıyla,bukaynaklararasındahassasbirdengekurmalıdırlar.Birmaden
işletmesininenkritikbölümlerindenbirisi,ekipmanfilosununoperasyonelkalımlılığıvegüvenilirliğinidevam
ettirmeyeyönelikbakımveonarımfaaliyetlerinigerçekleştirenveplanlayanbakımveonarımbölümüdür.Bu
bölümler,farklıteknik yeterlilik ve branşlardainsankaynağınaihtiyaç duymaktadırlar.Bir bakımve onarım
bölümüiçingereklifarklıniteliklerdekipersonelsayısı,ilgilimadencilik operasyonundaçalışanekipmanlar,
bunların maruz kaldıklarıarıza modları,bu arızaların ortaya çıkış frekansları ve sonrasında gerçekleştirilen
onarım sürelerigibifaktörlerdenetkilenmektedir.Arızafrekansları,bakımveonarımsürelerive arızamodu
için görevlendirilen çalışan sayısı gibi belirsizlikler farklı seviyelerdemevcut olup, belirsizliğin arttığı
durumlarda çalışan noksanlığına bağlı olarak bakım ve onarım yapılamama durumları da sıklıkla
gözlenmektedir. Bir sahada, gereğinden fazla personelin çalıştırılması bakım ve onarım faaliyetlerinin
zamanında yapılmasına olanak sağlarken, yüksek fiziki giderlere de neden olmaktadır. Bu durum, bakım-
onarımpersoneliazlığıveçokluğudurumlarındaoluşabileceküretimkayıplarıvefizikimasraflararasındabir
değiş-tokuşnoktasıyanioptimizeedilmesi gerekli birproblemiyaratmaktadır. Mevcut araştırma çalışması,
işleyen bir maden alanında farklı ekipman ve arıza modu davranışlarını dikkate alan ve buna göre farklı
branşlarda gerekli bakım ve onarım personel sayılarını optimize etmeye çalışan bir simülasyonmodelinin
oluşturulmasını amaçlamaktadır. Böylelikle; model, maksimum verimlilik ve performansı sağlamakiçin
gereklipersonellerifarklıekipmanarızamodlarınatahsisetmeyihedeflemektedir.
Anahtar Sözcükler: Sürekli-OlaySimülasyonu, Optimizasyon,Bakım ve Onarım,Madencilik,Makineve
Ekipman,İşgücü
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
541
Cite as: Sahiner, S. F. and Golbasi, O. (2023). Simulation-Based Optimization of Maintenance Crew Configuration in Mining Sites.
Proceedings of the 28th International Mining Congress and Exhibition of Türkiye (pp. 541-549). Antalya: UCTEA Chamber of Mining Engineers.
ABSTRACT
The minin g sector is a produc tion industry that re quires the effic ient and interacti ve use of limited
resourcessuchashumanresources,provenreserves,andequipmentfleets.Miningcompaniesmustestablisha
delicatebalanceamong theseresourceswiththeaimofachievingmaximumproductivityandefficiency.One
ofthemostcriticaldepartmentsofaminingoperationisthemaintenanceandrepairdepartmentresponsiblefor
performingandplanningmaintenanceandrepairactivitiestoensuretheoperationalreliabilityandreliability
oftheequipmentfleet.Thesedepartmentsrequirehumanresourceswithdifferenttechnicalcompetenciesand
specialties. The number of personnel with different qualifications required for a maintenance and repair
departmentisinfluencedbyfactors suchasthe equipmentused inthe relevant miningoperation,thefailure
modes t hey are exposed t o, the frequencie s at which these failures occur, a nd the subsequ ent repair times.
Uncertaintiessuchasfailurefrequencies,repairtimes,andthenumberofemployeesassignedtofailuremodes
often exist at differentlevels, andinsituations whereuncertaintyincreases,casesofmaintenanceandrepair
notbeingcarriedoutduetoashortageofpersonnelarefrequentlyobserved.Employinganexcessivenumber
ofpersonnelinthefieldallowsmaintenanceandrepairactivitiestobecarriedoutontimebutalsoleadstohigh
physicalexpenses.Thissituationcreatesatrade-offpointbetweenproductionlossesandphysicalexpensesthat
needtobeoptimizedwhenitcomestotheshortageorexcessofmaintenanceandrepairpersonnel.Thecurrent
research aims to create a simulation model that takes into account different equipment and failure mode
behaviorsinaworking miningarea and attemptsto optimizetherequiredmaintenanceandrepairpersonnel
numbers in different specialties accordingly. Thus, the model aims to allocate the necessary personnel to
differentequipmentfailuremodestoachievemaximumefficiencyandperformance.
Keywords: ContinuousEventSimulation,Optimization,MaintenanceCrew,Mining,Workforce
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
542
INTRODUCTION
With mass production and gl obalization improvem ents, machines hav e become crucial in various
manufacturingsectors.Consequently,astrongcorrelationbetweenproductionoperationsandmaintenancehas
become e ssential for the overall success of com panies. Equipment m alfunctions can dire ctly or indirectly
disruptproduction,resultinginsignificantfinanciallosses.Therefore,ithasbecomeimperativeforproduction
companies to establish a competent and well-organized maintenance department with a skilled workforce
possessingdiversecompetenciestoensureuninterruptedproduction.Intheminingsector,whichheavilyrelies
onmachinery, miningcompanies mustalso establish efficient maintenance departmentsin their operational
areas.Mining equipmentvariesincomplexityandis used insurface mines,underground mines,andmineral
processingfacilities, facing multiple failuremodes thatdemanddifferent maintenanceactions. Maintenance
workshops comprise units and employees with diverse qualifications in mining areas. Additionally, the
maintena nce policies in mining are diver se and complex, with main tenance work repres enting a substantial
shareoftheoperatingcost.Therelationshipbetweenmaintenanceandoperatingcostsintheminingindustry
has been extensively discussed in various studies and literature. The findings reveal several important
observatio ns; for instance , equipment m aintenance cos t in mining con stitutes a signifi cant portion, ran ging
from20% to 35%,ofthetotal operating cost(Unger and Conway,1994).Inspecific regionslike Chileand
Indonesia, m aintenance cos ts for surface min es surpass 60% of the operating cost (Won g et al., 2000). In
addition,maintenancecostsdominateasubstantialportionoftheequipmentoperatingcostacrossthemining
industry,ranging from40%to50% (KumarandForsman,1992). Moreover, a Finnishcompany sharedthat
maintenance costsin theirmines account forapproximately 30% of theproduction cost (Harjunpaa,1992).
Lastly, un planned mainten ance activities ha ve been shown to lead to a 10% production lo ss in Australian
undergroundcoalmines(Clark, 1990).Theseobservationsunderscorethesignificantimpactofmaintenance
costs on the overall operational expenses in the mining sector and highlight the importance of effective
maintenancestrategiestoensureefficientanduninterruptedproduction.
Theliteraturehighlightsthatmaintenanceisunavoidableinmachinery-basedproductionindustriesand
can significantly impact operating costs, leading to both direct expenses and indirect consequences like
productionloss.Therefore,whendevisingmaintenancepolicies,itiscrucialtodevelopabalancebetweenthe
physical cost of maintenancework and the value of production loss per unit. The composition of the
maintena nce crew, referring to the number of ind ividuals with different qua lifications, is a critical factor in
makingmaintenance-relateddecisions.Findingtherightbalanceinthemaintenancecrewisessentialasboth
over-employmentandunder-employmentcanaffectthecostdynamics,includingdirectandindirectexpenses.
Thisstudyaims to developa continuoussimulationalgorithmtodetermine the optimalmaintenance
crew in t erms of quantity and qualification. The objective is to minimize the overall cost, con sidering the
stochasticnatureofequipmentfailuresexperiencedataminingsite.
Problem St atement
Maintenance plays a crucialrole in production areas,as itenhancesand sustains the reliability and
functionality of systems. However, maintenance activities can lead to production loss if the maintenance
departmentlacksthenecessaryworkforce.Additionally,maintenanceactionscanbeexpensiveandlimitedby
available resources. Hence, balancing system breakdown costs and maintenance expenses is essential.
Neglecting maintenance can re sult in excessiv e failures, leadi ng to downtime a nd system dete rioration. To
ensure sustained production and improved operational profitability, it is crucial to establish an optimal
maintenance policy that minimizes both direct and indirect cost items related to employee expenses. In
machine-intensive sectors suchasmining,where production relieson multiple well-coordinatedheavy-duty
machines , maintenance cost sc an be substantial and sig nificantly contri bute to the total operatin g cost. The
maintenance cost included in the operating cost budget can differ significantly across industries. For the
manufacturingindustry,ittypicallyrangesfrom3%to15%,whileformetallurgicalprocesses,itfallsbetween
15%and20%.However,inthehighlymechanizedminingindustry,theaccountedmaintenancecostcanbeas
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
543
highas50%(Ben-Dayaetal.,2016).Furthermore,innumerousindustries,thechallengeofallocatinglimited
resourcestoaspecificsetoftasksisacommonoccurrence.Atthispoint,optimizinglaborresourceallocation
andconfigurationisessentialtoenhancesystems'servicelevelswhileminimizingdirectandindirectcosts.In
the case of a highly machine-intensive industry like mining, determining the optimal human resource
configurationformaintenanceactivitiesbecomesverycrucial.
Objective & Scope of the Study
Thecurrentstudyaimstodevelopasimulationalgorithmcapableofoptimizingthemaintenancecrew
configurationinanoperationinvolvingmultipletypesofequipmentwithrandomfailuremodes.Theprimary
goalistominimizethecumulativecostassociatedwiththe maintenancecrew,encompassingbothdirectand
indirectcostitems.Directcrew-inducedcostsincludevariouselementssuchassalary,insurance,foodservice,
shuttle servic e, rent help, and fa mily help. Indire ct costs, on the other hand, encompas s production losses
resulting from scheduled maintenance downtime and potential unavailability of the maintenance crew. In
addition to themainobjective,the study aimstoachieve severalsub-objectives. First,anindustrialresearch
componentisconductedtoinvestigatethefactorsdeterminingmaintenancecrewconfiguration,specificallyin
theminingindustry.Understandingthesefactorsiscrucialforoptimizingthecrewstructureeffectively.
Besides, the studyseekstoestablishthedependenciesbetweenproduction lossandthemaintenance
workforce.Byunderstandinghowthesetwofactorsarerelated,theresearcherscanbetterdesignamaintenance
crew config uration that minimi zes production los ses. To facilitate the ob jectives, the resea rch endeavors to
develop a m aintenance cre w simulation algor ithm within a cont inuous event sim ulation environme nt. This
algorithm will enable the evaluation and optimization of the crew configuration under various scenarios.
Moreover, the study involves implementing the developed model using an operational dataset after pre-
processingdata groups.This practicalimplementationusing real-world datawillenhancethe reliability and
relevance of t he results. Lastly , the researchers fo cus on verifying a nd validating the developed simu lation
algorithm toensure itsaccuracyandeffectiveness in optimizing themaintenance crew configuration.In the
applicationpart, thestudy utilizesthe historical maintenance dataset of a five-excavatorfleet operating in a
surfacecoalmine.Thefailuresarecategorizedintotwocommontypes:mechanicalandelectrical.
LITERATURE REVIEW
Maintenancecanbedefinedastheauxiliaryactivitiestoensurethatasystem,whichmayhavevarying
complexity and functions, remains in a satisfactory state by conducting regular checks, replaceme nts and
repairs on its components. As aresult, amaintenance policyinvolves a combination of actionswith distinct
objectivestoenableacomponenttofunctioneffectivelythroughoutthesystem'sentireservicelife.Theprimary
purpose of ma intenance action si s to enhance the func tionality and depend ability of systems .N evertheless,
improving reliability can be expensive in certain situations and is constrained by technical and financial
limitations. Consequently, there exists a delicate balance between the economic impact of maintenance
activities andthepotentialdeteriorationofthesystem.Toensure optimalresults,amaintenancepolicymust
bedesignedtomaintainthesystem'sreliabilityabovethedesiredlevel,takingintoaccountitsroleandvalue
inproduction.However,itisessentialtoavoidimplementingexcessivelyhigh-ratedpreventiveworkpackages,
as they may lead to additional investment costs and increased system unavailability due to preventive
downtimes.
Foraminingcompany,threecriticalassetsarecrucial:humanresources,orereservesforexploitation,
and an equipment fleet. Among these, human resources employed in operational areas hold particular
significance.Thenumberandqualificationsofpersonnelmustbedeterminedbasedonthedivisionalcapacity
requireme nts in mining areas. N otably, the mainte nance facility is obse rved to be the most lab or-intensive
aspect, asit requiresa considerablenumber ofindividuals withdiverse qualifications to ensure theoptimal
performan ce of the equipment fleet. Several studies have focused on mining equipm ent maintenance and
managementdecision-makingprocessesfortheminingsector.
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
544
Barberá etal.(2014) utilized theGAMMmethod toanalyze two slurry pumps in amining plantin
Chile,suggestingimprovementsforpumpmaintenance.AliandReza(2014)developedanewapproachusing
statistical modelstodetermineloading equipment'soverhaulandmaintenancecostinsurfacemining. Morad
etal.(2014)investigatedmaintenancepoliciesforoperatingtrucksinSungunCopperMinetominimizefailure
downtimes.Kovacevicetal.(2016)describedatwo-stepmethodtoanalyzefactorsinfluencinghumanerrors
duringminingmachines'maintenanceactivity.Nikulinetal.(2016)presentedacomputer-aidedapplicationto
evaluatetheoperationalandmaintenancestrategyforcomplexprocesseswithequipment.GölbaşıandDemirel
(2017)developedasimulationalgorithmtooptimizeinspectionintervalsandminimizemaintenancecostsfor
miningmachines.Jonssonetal.(2018)discussedanalyzingdigitalizedcondition-basedmaintenancedatainan
iron ore mine. Angeles and Kumral (2020) proposed a maintenance management approach to improve
equipmentavailability and reliability inaminingtruck fleet. These studies contribute valuable insights and
practical tools for effectively maintaining mining systems regarding cost minimization and availability
maximization.
In addition, various simulation studies in the mining industry have been conducted to evaluate
uncertaintiesattheoperationallevel,optimizeprocesses,andaddressvariousaspectsofminingoperations.For
instance, Hashemi and Sattarvand (2014) developed a model using discrete-event simulation to analyze
interaction s between loadi ng and hauling syst ems in mines, r esulting in improved dispatching sy stems and
reducedtruckqueueingtime.UpadhyayandNasab(2018)presentedasimulationandoptimizationframework
toenhanceshort-termproductionplanninganddecision-makinginminingoperations,consideringuncertainties
and dependencies between various factors. Golbasi and Demirel (2017) introduced an inspection interval
optimize r using a stochast ic, continuous , and dynamic simulation str ucture to determ ine the best co st-wise
decisionsinequipmentmaintenancepolicies.
Other studies explored optimiza tion in truck dispatching and allocation to shovels (Moradi et al.,
2019), truck allocation considering uncertainties in dispatching operations (Moradi et al., 2019), and the
effectof humanfactorsonminingequipmentreliability(Ozdemirand Kumral,2018).Additionally,Ozdemir
and Kumral (2019) proposed a two-stage dispatching system to maximize the utilization of truck-shovel
systems, le ading toi ncreased material quantity .Gol basia ndTu ran(2 020) introduced a maintenance po licy
optimizer todetermine optimal maintenance work packages based on equipment uptime and downtime
character istics. Bernardi et al. (2 020) compared mat erials handling sy stems in a mine to optim ize handling
systemsand minimizeoperatingcostsusingdiscreteeventsimulation.GolbasiandKina(2022)developeda
fuelconsumptionsimulatortoevaluatefuelusageinhaultrucksoperatingunderstochasticconditions.
These studieshaveprovidedvaluable insightsandpracticaltools for effectively maintaining mining
systemsregardingcostminimizationandavailabilitymaximization,improvingminingoperations,optimizing
maintenance policies, and enhancingdecision-making processes. However,optimization of human resource
configurationinminingactivitieshasnotbeenobservedintheliterature.
MODEL DEVELOPMENT
The algorithm's objectiveis todetermine the optimal maintenance crew configuration for a mining
area,ensuringthemostcost-effectiveoperationbystrikingabalancebetweenphysicalexpensesandproduction
losses re sulting from over or under-employm ent of skilled wor kers. The mainten ance crew incurs v arious
physicalcostitems,includingwages,employmentinsurance,foodservice,transportation,andaccommodation.
Over-employment in different maintenance branches can lead to a significant increase in direct costs.
Conversely,under-employmentinamaintenancebranchcancausenotableproductionlossesasrelatedfailure
types may n ot receive timely at tention, impac ting machinery avai lability. It is cruc ial to avoid overla pping
maintenanceactivitiesforsimilarfailuremodesthatrequiresimilartechnicalcompetency,asfailuretoevaluate
failure mode characterization and crew member occupancy rates jointlycan disrupt machinery availability.
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
545
Giventhatminingareasutilizenumerousequipmentwithvaryingnumbersandoperationalrequirements,
any misjudgment in maintenance behavior can lead to catastrophic situations, reduce equipment
utilization, and result in additional unavailability periods that harm short-term production plans. The
algorithmlogicisillustratedinFigure1briefly.
Figure1.SimulationModelAlgorithm
The model was tested on a fleet of five excavators, each with distinct failure occurrence and
maintenance characteristics. Failures were categorized into mechanical and electrical types, which
determinedthe crewgroups.Through200simulations,theinteractionswithin the systemwereevaluated
by varyin g the total numb er of mechanical an d electrical crew members in each run. Each simulat ion
coveredanobservationperiodof4,383hours.Theresultsindicatedthattheoptimizedcrewconfiguration,
consisting of 4 members inthe electrical and 4 members in the mechanical divisions, minimized the
cumulativedirectandindirectcosts.Thefleet'sgeneralevaluation,includingfiveexcavators,canalsobe
seenandFigure2.
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
546
Figure2.TotalDowntime(B)andTotalCost(A)for5ExcavatorsforEachCrewPolicy
CONCLUSIONS
In a machine-based production company, the maintenance department consists of various
divisionswithdifferentcrewconfigurations,dependingonthecompany'sproductionprofile,complexity,
andtypesofmachinesinvolvedinproductionphases.Inminingareas,operationscanbeeithersurfaceor
underground, depending on the mining method, and specific heavy-duty machinery with varying
production rates is requiredbased on the mining type and production capacity. A mining company
typically possesses a large fleet of machines, including loading, hauling, drilling, and auxiliary
equipment.Eachmachinemayexperiencedifferentfailuremodeswithvaryingoccurrencefrequency and
consequences,resultingindifferentdowntimeprofiles.
Given that the m aintenance cre w is a limited resource with specific num bers of people in each
division,it is crucial to determine the optimal configuration of the maintenance crew, considering the
trade-of fbet weenthe total financial co nsequences of diff erent crew config urations. To addr ess this, the
studydevelopsa multi-scenario continuous-eventsimulationmodeltoidentifytheoptimalcapacityand
qualification of the maintenance crew for a functional mining operation. The developed model is
implemented for the maintenancecrew requirement of a fleet covering five excavators experiencing
randomfailureswithvaryingmaintenancerequirementsanddurations.Theoverallcostis minimizedfor
acrewconfigurationwith4and4peopleintheelectricalandmechanicaldepartments.
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
547
References
Angeles, E., & Kumral, M. (2020). Optimal Inspe ction and Preventive Maintenance Scheduling of Mining
Equipment. Journal of Failure Analysis and Prevention, 20(4), 1408–1416.
https://doi.org/10.1007/s11668-020-00949-z
Barberá,L., Crespo,A., Viveros,P.,&Stegmaier,R.(2014). Acasestudyof GAMM(graphicalanalysis for
maintenancemanagement)intheminingindustry. ReliabilityEngineeringandSystemSafety, 121,113
120.https://doi.org/10.1016/j.ress.2013.07.017
Ben-Daya , M., Kumar, U., & Mur thy, D. N. P. (2016). Int roduction to mai ntenance enginee ring: modelling,
optimizationandmanagement.
Bernardi,L.,Kumral,M.,&Renaud,M.(2020).Comparisonoffixedandmobilein-pitcrushingandconveying
and truck-shovel systems used in mineral industries through discrete-event simulation. Simulation
ModellingPracticeandTheory,103,102100.https://doi.org/10.1016/j.simpat.2020.102100
Clark, D.: T ribology – its appl ication to equipme nt reliability and m aintainability de sign in the underg round
coalminingindustry.In:ProceedingsoftheInstitutionofEngineersAustraliaTribologyConference,pp.
38–44(1990)
Demirel, N., Minerals, O. G.-, & 2016, undefined. (2016). Preventive replacement decisions for dragline
componentsusingreliabilityanalysis.Mdpi.Com.https://doi.org/10.3390/min6020051
Forsmann,B.,Kumar,U.:Surfaceminingequipmentandmaintenancetrends inthescandinaviancountries.J.
MinesMineralsFuelsAugust/September266–269(1992)
Golbasi, O., & Demirel, N. (2017). Simulation of an Active Maintenance Policy: A Preliminary Study in
Dragline Maintenance Optimization. Lecture Notes in Mechanical Engineering, 669–679.
https://doi.org/10.1007/978-3-319-23597-4_49
Golbasi, O., & Kina,E.(2022).Haultruck fuelconsumption modelingunderrandomoperating conditions:A
case study. Transportation Research Part D: Transport and Environment, 102, 103135.
https://doi.org/10.1016/j.trd.2021.103135
Golbasi, O., & Turan, M. O. (2020). A discrete-event simulation algorithm for the optimization of multi-
scenariom aintenance pol icies. Computers & Indus trial Engineering ,1 45, 106514.
Harjunpaa,H.:Howtodeterminetheeffectivenessofanindustrialmaintenanceorganizationanditsinfluence
on the profitability of a company. In : Proceedings of the Eu ro Maintenance Conf erence, pp. 101–104
(1992)
Hashemi,A.S.,&Sattarvand,J.(2014).LNPE9-ApplicationofARENASimulationSoftwareforEvaluation
of Open P it Mining Tran sportation Sy stems – A Case S tudy. https://d oi.org/10.1007/97 8-3-319-1230 1-
1_20
https://doi.org/10.1016/J.CIE.2020.106514
Jonsson, K.,Mathiassen, L., Holmströ, J.,& Jonsson,K. (2018). Representation andmediation in digitalized
work:evidencefrommaintenanceofminingmachinery.https://doi.org/10.1057/s41265
Kovacevic,S.,Papic, L.,Janackovic,G.L.,& Savic, S.(2016).The analysisof humanerroras causesinthe
maintenance of machines: A case study in mining companies. South African Journal of Industrial
Engineering,27(4),193–202.https://doi.org/10.7166/27-4-1493
Lashgari, A., & Sayadi, A. R. (2013).Statisticalapproachtodeterminationof overhaulandmaintenance cost
ofloadingequipmentinsurfacemining.InternationalJournal ofMiningScienceandTechnology,23(3),
441–446.https://doi.org/10.1016/j.ijmst.2013.05.002
Morad, A. M., Pourgol-Mohammad, M., & Sattarvand, J. (2014). Application of reliability-centered
maintenanceforproductivityimprovementof openpitminingequipment:CasestudyofSungun Copper
Mine.JournalofCentralSouthUniversity,21(6),2372–2382.https://doi.org/10.1007/s11771-014-2190-2
Moradi Afrapoli,A., & Askari-Nasab,H. (2019).Mining fleetmanagementsystems:areviewofmodels and
algorithms. International Journal of Mining, Reclamation and Environment, 33(1), 42–60.
https://doi.org/10.1080/17480930.2017.1336607
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
548
Moradi Afrapoli, A .,T abesh, M., & Askari-Nas ab, H. (2019a). A mul tiple objective tra nsportation problem
approachto dynamic truck dispatching in surface mines. European Journal of Operational Research,
276(1),331–342.https://doi.org/10.1016/j.ejor.2019.01.008
Moradi Af rapoli, A., Tabesh , M., & Askari- Nasab, H. (2019 b). A stochastic h ybrid simulation -optimization
approach towards haul fleet sizing in surface mines. Mining Technology, 128(1), 9–20.
https://doi.org/10.1080/25726668.2018.1473314
Nikulin, C., Ulloa,A.,Carmona,C.,&Creixell, W. (2016).AComputer-aidedApplicationforModelingand
Monitoring Operational and Maintenance Inf ormation in Mini ng Trucks. Archi ves of Mining Scie nces,
61(3),695–708.https://doi.org/10.1515/amsc-2016-0048
Ozdemir,B., &Kumral,M.(2018).Appraisingproductiontargetsthroughagent-basedPetrinetsimulationof
material h andling system s in open pit m ines. Simula tion Modellin g Practice and Theory, 87, 138– 154.
https://doi.org/10.1016/j.simpat.2018.06.008
Ozdemir,B.,&Kumral, M.(2019).Simulation-basedoptimizationoftruck-shovelmaterial handlingsystems
in multi-pit surface mines. Simulation Modelling Practice and Theory, 95, 36–48.
https://doi.org/10.1016/j.simpat.2019.04.006
Unger, R. L.andConway,K.(1994),Impact ofmaintainability designoninjury ratesand maintenance costs
forundergroundminingequipment,inImprovingSafetyatSmallUndergroundMines,compiledbyR.H.
Peters,ReportNo.SpecialPublication18–94,USBureauofMines,Washington,pp.140–167.
Upadhyay, S. P., & Askari-Nasab, H. (2018). Simulation and optimization approach for uncertainty-based
short- termplanninginopen pit mines. International Journal of Mining Scienceand Technology, 28(2),
153–166.https://doi.org/10.1016/j.ijmst.2017.12.003
Wong, J.,R.A. &Daneshmend, L.K.& Lipsett, M.& Hall. (2000).Reliability analysis as atool forsurface
miningequipmentevaluationandselection.CIMBulletin.93.78-82.
IMCET2023/ANTALYA/TÜRKİYE/November28-December1
549
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
This research study evaluates kinematic fuel consumption factors of haul trucks employed simultaneously in a multi-route operation network under stochastic payload and precipitation conditions. First, a discrete-event simulation algorithm was introduced, and significant parameters available in a material haulage system were correlated with time and location-based fuel usage behavior. Then, the model was validated with a large-scale cement production network covering two separate mines and one processing plant where fifteen different routes and twenty-nine trucks were available. The simulation results showed that precipitation conditions might lead to a variation in fuel consumption by 15–25 percent. Besides, the same-capacity trucks employed in the clay mine were detected to consume 40 percent more fuel in loaded travel than the limestone mine trucks due to the higher frequency of uphill loaded travels. The clay mine trucks also released 1.48 kg/km carbon dioxide in a complete production cycle, which is 17.5 percent more comparatively.
Article
Full-text available
Accuracy in predictions leads to better planning with a minimum of opportunity lost. In open pit mining, the complexity of operations, coupled with a highly uncertain and dynamic production environment, limit the accuracy of predictions and force a reactive planning approach to mitigate deviations from original plans. A simulation optimization framework/tool is presented in this paper to account for uncertainties in mining operations for robust short-term production planning and proactive decision making. This framework/tool uses a discrete event simulation model of mine operations, which interacts with a goal-programming based mine operational optimization tool to develop an uncertainty based short-term schedule. Using scenario analysis, this framework allows the planner to make proactive decisions to achieve the mine's operational and long-term objectives. This paper details the development of simulation and optimization models and presents the implementation of the framework on an iron ore mine case study for verification through scenario analysis.
Article
A typical mining company has three important assets: the human labor-force, the orebody, and the equipment. Trucks, excavators, drilling machines, crushers, grinders, classifiers, and concentrators represent the equipment. Mining operations that want to take advantage of economies of scale have huge equipment fleet, and the worth of the equipment could be more than a hundred million dollars. The reliability and availability of this equipment play critical roles in increasing the efficiency and productivity of a mining operation. This paper proposes an effective maintenance management approach to be used in the mining industry such that equipment availability and reliability are improved while potential failures are prevented. Using failure data of a mining truck fleet in an open-pit Canadian mining operation, a case study is conducted in two steps. The first step focuses on determining optimal inspection intervals based on the desired reliability level in such a way as to detect potential catastrophic failures that represent considerable maintenance and downtime costs. The second step develops a preventive maintenance scheduling plan that differentiates between physical and virtual age considering the degradation of systems and their rejuvenation after each repair. The research outcomes show that the proposed approach has the potential to increase the benefit obtained from the mining equipment and can be used in mining operations.
Article
In-pit crushing and conveying (IPCC) systems (whether fixed, mobile, or semi-mobile) are an alternative to the traditional truck/shovel approach to materials handling. However, assessing the viability of one of these systems for an existing or planned open-pit mine from an operational standpoint presents a great deal of challenge given the complexity of the problem. This research applied the discrete event simulation to model the materials handling system of a mine to assess the applicability and weaknesses of the technique for such use. Varying configurations of a mine's geometry were fed into the simulation then run and optimized for cost using the discrete event simulation tool. The development of the model and simulation highlighted the potential for discrete event simulation to serve as a rapid tool to compare IPCC and truck/shovel systems by assessing those parameters and associated costs inherent with the operating realities of each system.
Article
Truck and shovel are the most widely used equipment in the mining industry, and their performances are highly interdependent. When a problem occurs in one type of equipment, the productivity of the other type of equipment is also affected. That is to say, shovel waiting times, truck queues and bunches on the roads, and idle capacity problems in crushers are experienced in such a way as to result in direct or opportunity costs. In this paper, a two-stage dispatching system is proposed to maximize the utilization of truck-shovel systems. In the first stage, the truck and shovel fleets are divided into sub-fleets to work on the specific pit by a simulation-based optimization method which considers uncertainties in the mining operation. In the second stage, the trucks are simultaneously dispatched to the shovels in the pit by linear programming. Match factor is also tracked in the second stage as a measure of the compatibility of the fleets. In surface mines which consist of more than one pit, the trucks can be reassigned to another pit during the operation to manage high match factors for all pits. The proposed approach is tested in a mine. When the ore and waste production quantities of the previous dispatching system and the proposed framework were compared, the total quantity was increased with the proposed framework by 9.4% in a shift which corresponds to 6.0 K tonnes of material. The approach has great potential to increase the productivity of truck and shovel systems.
Article
In surface mining operations, fleet management systems seek to make optimal decisions to handle material in two steps: path production optimization and real-time truck dispatching. This paper develops a multiple objective transportation model for real-time truck dispatching. The model addresses two major drawbacks of former models. The proposed model dispatches the trucks to destinations trying to simultaneously minimize shovel idle times, truck wait times, and deviations from the path production requirements established by the production optimization stage. To evaluate the performance of the proposed model, we developed a benchmark model based on the backbone of the most widely used fleet management system in the mining industry (Modular Mining DISPATCH). Afterward, we built a discrete event simulation model of the truck and shovel operation using an iron ore mine case study, implemented both of the dispatching models, and compared the results. The implementation of the models suggests that the multiple objective model developed in this paper is able to meet the production requirements of the operation using a fleet at 85% of the size of the deterministically calculated desired fleet. In addition, the model is able to meet the full capacity of the processing plants with a fleet of 30% less trucks than the desired fleet.
Article
In a mining operation, significant differences between production targets in the planning stage and actual production quantities are a common issue. These differences can be related to heterogeneity of quality of ore within orebody, availability, and reliability of mining equipment, design-related problems of mining activities, and external factors. One way to understand the feasibility of targeted production rates is to simulate the activities. In this paper, an agent-based Petri net simulation model is proposed to check whether production targets are feasible, and the extent to control head grade in mineral processing. The model evaluates different realizations under the uncertain operation environment. Moreover, the fuel consumption of haul trucks is tracked in the proposed model. A case study was carried out to evaluate the proposed approach in an open pit mine. The research outcomes showed that this approach could assist in capacity installation, mineral processing design, and fuel tracking in mining operations.
Article
Haul fleet size determination is a critical task in any surface mining operation where the material is handled using the truck-and-shovel system. Although the problem of finding the optimum haulage fleet size has been thoroughly studied, there are two important shortcomings: disregarding the effects of downstream processes on the operation and ignoring the fleet management system effects. This paper presents an integrated simulation-optimization framework to address the haul fleet size determination problem surface mines and target the two shortcomings listed above. In the developed framework, the mining operation, the processing plants, and the operational decision tools communicate with each other to find the best size of the haul fleet required to meet the production schedule. Results of the study show that the developed framework is capable of handling the operation with 13% less number of trucks than the required number of trucks suggested by deterministic calculations.