2 Condition Based Maintenance

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Condition Based Maintenance

Dr. Ir. M. Sabri, MT


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Definisi dan Tujuan CBM

Perawatan Berbasis Kondisi (Condition BasedMaintenance, CBM) adalah seperangkat tindakanperawatan berdasarkan real-time atau penilaian waktuterdekat-sebenarnya dari kondisi peralatan yang dapatdiperoleh melalui sensor tertanam dan / atau tes eksternal& pengukuran yang dilakukan dengan alat portabel.

Tujuan dari strategi CBM adalah untuk menjalankanperawatan hanya jika terdapat bukti obyektif darikebutuhan, sambil memastikan keamanan, keandalanperalatan dan pengurangan biaya total kepemilikan.


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What is CBM?

Proses condition based maintenance (CBM) memerlukanteknologi, keterampilan, dan komunikasi untukmengintegrasikan semua kondisi data peralatan yangtersedia, seperti: data diagnostik dan kinerja; sejarahpemeliharaan; log operator, dan data desain, untukmembuat keputusan yang tepat waktu tentang persyaratanpemeliharaan utama/peralatan penting.

Metodologi baru ini telah dikembangkan bertahun-tahun,yang sebenarnya, telah berkembang dari metodepemeliharaan terdahulu selama tiga dekade terakhir.


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CBM Phillosophies

CBM menganggap bahwa semua peralatan akanmenurun kondisinya dan bahwa akan terjadi hilangnyasebagian atau seluruh fungsi

CBM monitors the condition or performance of plant

equipment through various technologies The data is collected, analyzed, trended, and used to

project equipment failures Once the timing of equipment failure is known, action

can be taken to prevent or delay failure Condition based maintenance uses various process

parameters (e.g. pressure, temperature, vibration, flow)and material samples (e.g. oil and air) to monitor

conditions


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CBM GoalsTujuan dari perawatan berbasis kondisi adalah untuk mengoptimalkankeandalan dan ketersediaan dengan menentukan kebutuhan untukkegiatan pemeliharaan berdasarkan kondisi peralatan. Menggunakan"teknik prediksi", teknologi, pemantauan kondisi, dan pengamatandapat digunakan untuk memproyeksikan ke depan dalam upaya untukmenetapkan waktu yang paling mungkin dari kegagalan dan tindakanini untuk meningkatkan kemampuan pabrik untuk merencanakan danbertindak secara proaktif.

PDM / CBM mengasumsikan bahwa peralatan memiliki indikator yangdapat dipantau dan dianalisis untuk menentukan kebutuhan kondisidiarahkan kegiatan pemeliharaan. Pemeliharaan berbasis kondisimemungkinkan biaya terendah dan program pemeliharaan yang palingefektif dengan menentukan aktivitas yang benar pada waktu yangtepat.


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CBM Benefits To reduce or eliminate unnecessary repairs, prevent

catastrophic machine failures and reduce the negativeimpact of the maintenance operation on the profitabilityof manufacturing and production plants

Condition based maintenance has the ability to reduce

the actual time required to repair or rebuild plantequipment (MTTR) A condition-based predictive maintenance program

prevents serious damage to machinery and other plant

systems (MTBF) Provides the means to verify the purchased condition ofnew equipment or offsite rebuilt before acceptance

Predictive data can provide the information required to

plan the specific repairs and other activities during theoutage


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CBM Advantages

A principal advantage of CBM is the capability itoffers the user to perform inspections while theequipment is operating.

Although the technical knowledge required forCBM inspections is usually higher than those forPM, the inspection time required per asset is muchless.

When comparing cost advantages of CBM overPM, consider customer downtime costs,maintenance labor costs, maintenance materialscosts, and the cost of holding spare parts ininventory.


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CBM Objectives

Improve availability i. Reduced forced outagesii. Improve reliability

Enhance Equipment Life i. Reduce wear from frequent rebuildingii. Minimize potential for problems in disassembly and

reassemblyiii. Detect problems as they occur

Save Maintenance Costs i. Reduced repair costsii. Reduced overtimeiii. Reduced parts inventory requirements


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CBM TargetsKondisi Berbasis Perawatan bukanlah pengganti metode manajemenpemeliharaan yang lebih tradisional. bagaimanapun, Hal ini, jaditambahan yang berharga untuk keseluruhan program pemeliharaanpabrik yang komprehensif.

Dimana program manajemen pemeliharaan tradisional mengandalkanservis rutin semua mesin dan respon yang cepat terhadap kegagalantak terduga, kondisi berdasarkan jadwal program tugas pemeliharaankhusus yang benar-benar dibutuhkan oleh peralatan pabrik.

CBM tidak bisa menghilangkan keseluruhan kebutuhan programpemeliharaan tradisional, yaitu mendekati-kegagalan dan preventif,pemeliharaan prediktif dapat mengurangi jumlah kegagalan tak terdugadan menyediakan alat penjadwalan yang lebih dapat diandalkan untuktugas-tugas pemeliharaan preventif rutin.


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Maintenance Strategies


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TDM versus CDM

Time-directed maintenance (TDM)Attempts to avoid failures by retiring, replacing oroverhauling components at a specific age (TBO)

Condition-directed maintenance (CDM)Attempts to avoid failures by monitoringcomponent condition to detect potential failuresbefore they become functional failures

CDM is always more efficient than TDMTDM should be used only when CDM is infeasible


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Decisions Tree


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CBM Demands

Real-time application High reliability At early stage, alert when fault is impending, so that

maintenance can be planned when asset is not beingused Identification of the fault and tell where the fault is

located

Classify faults in different categories, when a fatal faultoccurs automated shut down should be a possibility The alerts should be easy to understand The system should be connected to a superior computer


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CBM Implementation ProcessConditions necessary for a successful implementation process are typicallyones of culture change and change management. They require substantialefforts by all site personnel and management.Commitment - The staff must have commitment to the process and itsnew technologies as well as their use. Staff has to trust the training and the

technology. Management must have the commitment to procure adequateequipment and training for the Staff.Part icipation - All groups must participate in the program. Theorganizations support for condition based maintenance must be 100% toachieve success. Management has to reinforce this expectation.Holis t ic appro ach - It applies to all systems throughout the plant. Noexceptions.Sus tainabil i ty - The program, its staff, its equipment has to be maintainedthrough time to ensure the long term benefits of the process. As peoplemove into and out of organizations, the needed resources must beavailable. This includes the management support and attitude to trust andmaintain it.


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CBM Implementation Process


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CBM Technologies


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Condition Monitoring Technologies


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Vibration Analysis

Today, electronic instrumentation is available that goes farbeyond the human limitations with which the old timecraftsperson had to contend when trying to interpretvibration signals with a screwdriver-handle-to-the-ear

method. Todays instruments can detect with accuracy andrepeatability, extremely low amplitude vibration signals.They can assign a numerical dimension to the amplitude ofvibration and can isolate the frequency at which thevibration is occurring. When measurements of bothamplitude and frequency are available, diagnostic methodscan be used to determine the magnitude of a problem and

its probable cause.


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Early detection ofmechanical fatigue andbreakdown

Vibration Analysis


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Vibration Analysisissues that can befound EARLY!

Vibration Analysis


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Sample Platforms

Vibration Analysis


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Vibration Analysis willfind defects

Avoiding disassembly andaverting unplanneddowntime

Vibration Analysis


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Vibration Analysis


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Vibration Analysis

When you use electronic instruments in organized andmethodical programs of vibration analysis you are able to:

Detect asset problems long before the onslaught of

failure Isolate conditions causing accelerated wear

Make conclusions concerning the nature of defectscausing asset problems

Execute advance planning and scheduling of correctiverepair so that catastrophic failure may be avoided

Execute repair at a time which has minimum impact on

operations


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Thermography

Infrared thermography has grown by leaps and bounds inthe past 10 years. Equipment is easier than ever to useand more effective. The real power of thermography is that

it allows quick location and monitoring of problems. Itpresents critical decision-making information in visual formmaking it easy for management to understand. Infraredimaging systems, as they are generally called, produce a

picture, either black or white or color, of the invisiblethermal patterns of a component or process. These thermalpatterns, when understood, can be used to monitor actualoperating conditions of equipment or processes.


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A widely used tool in all facets of industry to measure anywhere a fault can bepredicted by a temperature differential.

Non-destructive tool in the analysis and evaluation of electrical distributionequipment.

Reference point of equipment temperature under normal operating conditions.

Thermography


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Thermography

Using infrared thermography. Thermography can beused to quickly locate equipment and process problemsand in preventing the recurrence of the following problems:

Catastrophic electrical failures

Unscheduled electrical outages or shutdowns

Chronic electrical problems in a piece of equipment orprocess

Excessive steam usage

Frozen or plugged product transport lines

An inability to predict failures accurately

Inefficient use of downtime maintenance opportunities


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Thermography

Friction failures in rotating equipment Poor product quality due to uneven hearing or cooling or

moisture content

A fire in a wall or enclosed space Inability to locate or verify a level in a tank

Replacement of refractory in a boiler, furnace, or kiln

A leaking flat roof Uneven room temperatures affecting product quality or

employee productivity

Trouble locating underground water, steam, or sewerlines


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What can Thermography find?

What you see What thermography sees

Overheating electrical connection indicates a serious fire hazard.

Thermography


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Indication of bearing overheating, will eventually cause failure

Thermography


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Can you afford not to have aThermography Survey?

Fire damaged electrical systemCruise Ship Fire Damage

Thermography


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Oil AnalysisThe spectrometric oil analysis process is a laboratory technique whichuses various instruments to analyze a used oil sample from a machine.

A spectrometer is used to show when a significant wear mode isunderway. Some varieties of these instruments can isolate up toperhaps 80 different types of metals in a sample. The spectrometric

result is compared to a baseline level of metal found to be typicallysuspended in the oil under normal operating conditions. An importantfeature of the spectroscopic method is that it not only determines theamount of metal in the sample but also the type. The analysis not only

permits the discovery of severe wear, but also analysis of the possiblelocation of severe wear in a machine. With this information you cantake timely action to prevent further deterioration, either by oilpurification, oil replacement, or some other means appropriate to theproblem.


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Oil Analysis is a non-destructive test used to assess the condition of lubricants anddetermine the type and amount of contamination present.

Criticality of lubrication to most industrial equipment, oil analysis trending over time isone of the most powerful predictive tools for identifying potential failures.

3 basic categories of elements affecting the lubrication effectiveness: wear metals,contaminants, and additives.

Oil Analysis


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Oil Analysis

In addition to the spectrometric analysis, the oil laboratoriesalso check the oil using common oil analysis techniques.For example, the oil is usually checked for viscosity. If the

viscosity of the oil has changed 5 percent from new oil ofthe same type, it is probably time for an oil change due tocontamination. Typical of these types of analysis are totalacid number, percent moisture, particle count (for hydraulic

systems), total solids, and percent silicon (representing dirtfrom the atmosphere in the form of silicon dioxide orperhaps just from an additive). With prior agreement,special tests are performed at additional cost.


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Benefits

Improve oil sampling methodswith emerging technologiesImprove machine condition and

reliability with oil analysisIncrease the remaining useful lifeof your lubricantReduce maintenance costsassociated with unplanneddowntime

Oil Analysis


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Early detection with oil analysis can allowfor corrective action such as repairing anair intake leak before major damageoccurs.

One of the major advantages of an oil analysisprogram is being able to anticipate problems andschedule repair work to avoid downtime during acritical time of use.

Oil Analysis


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Oil Analysis

The relatively low costs of spectrometric oil analysis make it avery valuable and commonly used CBM method. It is practicalfor asset systems and subsystems that have a reasonableinventory of oil and are provided with reuse methods of oilapplication such as circulating, bath, splash, flood, and ring-oiling designs. In addition to providing advance warning whensevere wear occurs, spectrometric oil analysis can giveimportant assistance in machine lubrication programs.Conventional oil change frequencies are arrived at according tothe traditional PM approach based upon time, hours, or milesoperated. A best estimate (or guess) is made of the time orcalendar period over which the oil in the system will degenerateand require changing under current operating conditions.Spectrometric oil analysis enables you to change oil only when

the actual condition of the oil requires.


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Condition Monitoring Standard


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Challenges in Implementing CBM

Accurate and Full Utilization of Data Variable Operating Patterns Complexities of Real-life Systems Documentation Customer Specific User Profiles


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Opportunities in Implementing CBM

Establish Root Causes of Failures and theConsequences

Reduce the Life Cycle Cost of Systems in theField


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CBM Reporting Action Report Containing:

- Asset ID, Date, Current Alarm Status, Fault, Action,Priority Missed Measurement Report listing:

- Asset ID, Date and reason measurements missed

Typical Action/Advisory Priorities:-


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Typical Action Report


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CBM Assessment


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CBM Design


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Framework for CBM DesignCondition Based

MaintenanceDesign

Selection of a Unitto monitor

Selection of theCondition

Indicator(s)

Selecting aPrognostic

Modeling approach

Determination ofthe Maintenance

Policy

Selection of a Unit to monitor - this selection process should be based on the potentialbenefits of a CBM program for a specific unit, and the impact of the failure modes of thisunit on the overall condition of a system.

Selection of the Condition Indicator(s) - to obtain insights into the relation between thefailure mode(s) of a specific unit and the related deterioration parameter(s).

Selecting a Prognostic Modeling approach - these models are divided into Knowledgebased models, life expectancy models, Artificial Neural Network (ANN) models, andphysical models.

Determination of the Maintenance Policy - determination of the maintenance policy, theoverall CBM program for the specific unit can be evaluated on profitability.


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MaintenanceDesign



Indicator(s)


Modeling approach


Policy

As the asset base of a company can be large and systemscomplex, criteria need to be formulated such that precious

resources, time and money are spent on the most importantassets of a company. Over different assets, the impact of a CBMprogram on the operational and technical costs can depend onnumerous factors.


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Selection of a Unit to monitor

System DecompositionDecomposition of the system into lower level units (i.e.components, items) for which the failure modes and interactionsare comprehensible is key at the start of a CBM program. By gaininginsights into these failure modes of the specific units, gradually, anoverall condition parameter for the system can be developed.Depending on the level of knowledge of these failure modes,analysis on the item, component, or system level is possible. Forexample, the wheels of a car can be considered as a unit, but also

the entire steering mechanism (i.e. all components enabling thefunction of steering) can be considered to be the unit for analysis.Depending on the way of defining the unit, different failure modeswill have different effects on the unit and will have different causesdepending on the level of decomposition.


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Selection of a Unit to monitor Criteria AnalysisAs the field of maintenancemanagement is concerned withproduction, finance and qualitywithin organizations, multiplecriteria can be involved inmaintenance decision making.Maintenance personnel can considerthe unit with the highest frequencyof failures to be the most critical unitwhile employees of the production

department can consider the unitwith the longest downtime to be themost critical one.Also, from a financial point of view, the spare parts consumptioncan be considered to be a criteria for defining the criticality of a

unit.


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Determining the Critical Failure ModesSome commonly used tools in the field of Root CauseAnalysis (RCA) are:-i. FMEA - supports the process of selecting the most

critical failure modes of a specific unit by evaluatingthe consequential damage related to it.ii. Pareto Analysis - aims at selecting the actions that

have the biggest impact on the overall result.iii. Ishikawa Diagram - by providing the relationships

between variables of influence on a specific event,these diagrams can give insights into specific processbehavior.


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Determining the Critical Failure ModesFMEA


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Determining the Critical Failure ModesPareto Analysis


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Bearing Failures Study


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Determining the Critical Failure ModesIshikawa Diagram

F k f CBM D i


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MaintenanceDesign



Indicator(s)


Modeling approach


Policy

After discussing the selection of a unit to monitor, it is importantto obtain insights into (1) the failure modes of the specific unitand relating these failure modes to a single or multipledeterioration parameters, (2) gather data on the deteriorationparameters, (3) gain insights into the deterioration process of aspecific parameter, and (4) define a failure threshold level tospecify at what condition level the unit is considered to be unableto perform according to functional specifications (i.e. the unit is

considered to be in the failed condition).

Selection of the Condition Indicator(s)


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Selection of the Condition Indicator(s) Relation Between Monitored Parameter and Deterioration

In order to make an accurate prediction of the deterioration conditionof a system, selection of correlated quantitative variables to thedeterioration is key. Insights into the failure modes and possible effectsof the system is crucial in this parameter selection process. Also, thefailure dependencies can play an important role in the parameterselection process. While some deterioration parameters correlate to asingle failure mode, some failure modes will need multipledeterioration measures to provide an accurate indication of thedeterioration condition. It should be noted that a situation might arisein which a deterioration parameter cannot be determined, thedeterioration parameter cannot be measured, or where it is too costlyto measure the deterioration parameter. Hence, an imminent mode offailure cannot be predicted. In these cases, implementation of a CBMprogram might not be efficient, depending on how critical this

parameter is with respect to predicting a system failure.


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Selection of the Condition Indicator(s) Data AcquisitionThe necessary data collected can be categorized in two types; event dataand condition monitoring data. The event data consists of informationextracted from information systems (e.g. CMMS, MIS). The collection ofevent data done by manual data entry into the information system couldresult in the erroneous entry of data in the system because of theinvolvement of human input. The condition monitoring data can fall intothree types of different data categories

- Value type data is collected data that is registered as a single valuevariable. Examples can be oil particles analysis data, temperature,

pressure and humidity data.- Waveform type data is data collected as a time series, which is referred

to as a waveform. Examples of these type of data are vibration data andacoustic data.- Multidimensional type data is data that is of a multidimensional

character. Most of the time this is some sort of image data like infraredthermographs, X-ray images or visual images.


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Trend EvaluationFor the purpose of predictability, the trendcharacteristics of the deterioration signal are key.Knowledge on the deterioration behavior over timeshould be obtained. Depending on this behavior, itis determined what the best model fit for thespecific unit is. This can for example be a linear orexponential model. Most important is to observe a

specific pattern over time. Often, a phase of normaloperation can be defined in the early lifetime of theunit.


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Trend Evaluation

The Potential Failure Failure (P-F) Interval


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Trend Evaluation

Lifetime Characteristics


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Determining a Threshold LevelDepicts the condition level of the item at which afunctional failure is likely to occur. This can happenbecause of actual failure of the unit, or because the unitfails to meet a functional requirement as specified by thecustomer or company. Relevant information can beacquired from (1) historical data, (2) from expert opinion,or in case no data is available for determining the

threshold level, (3) a tentative threshold level can beselected in order to gain more insights and obtain moreexperience with the deterioration of the unit.

Framework for CBM Design


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MaintenanceDesign



Indicator(s)


Modeling approach


Policy

As the condition parameters defined and deterioration data are gathered,the selection of the prognostic model is considered to be notstraightforward within companies as this requires both knowledge on howthe model should be used and understanding of the mathematical

background of the model. This chapter provides an overview into thedifferent models available for the purpose of prognostic modeling and therelevant selection criteria. As depicted in figure 13, the area of prognosticmodels can be generally divided into; (1) knowledge based models, (2) lifeexpectancy models, (3) Artificial Neural Network (ANN) models, and (4)

physical models.


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Selecting a Prognostic Modeling approach

Knowledge Based ModelsWithin the knowledge-based models, the RUL is determinedusing historical data. These events are compared to a databaseof failure events based on historical data and expert knowledge.The knowledge-based models can be divided into a class of:-

Fixed Rule SystemsThe knowledge from experts is gathered and used to define ruleswithin a software program. This can be done by formulating if-then statements for specific problem situations.

Fuzzy SystemsUse simple if-then rules based on empirical data to solveproblems. However, the rules are defined based on specificconditions. (e.g. if(friction is high) and (temperature buildsquickly) then (cool down))


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Selecting a Prognostic Modeling approach

Life Expectancy ModelsThe life expectancy models determine theRemaining Useful Life (RUL) of a unit by

assessing the risk of degradation under knownoperating conditions. The life expectancymodels can be classified into the group of:-

(1) stochastic models, and

(2) statistical models.


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Selecting a Prognostic Modeling approach Artificial Neural Networks (ANN)ANNs predict the RUL of a unit by using amathematical representation of the unit which isbuilt from historical observations. Therefore, this

approach lacks understanding of the underlyingphysical failure processes. It is typically used formodeling complex non-linear units by using inputdata such as process variables, condition

monitoring data, unit characteristics andmaintenance history data to give the desiredmaintenance action or the RUL as output of thenetwork model


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Selecting a Prognostic Modeling approach Physical ModelsPhysical models assumes that physical laws can beused to quantitatively model the behavior of a unit.This is done by using scientific or empirical

knowledge and transforming this into adeterministic equation to estimate the RUL. Toenable this, unit specific parameters need to beidentified to build this equation. Sensory

measurements are used to compare the model withthe real-life unit behavior. A drawback of thismethod is that the failure behavior of a unit isinfluenced by a lot of different variables.

Framework for CBM Design


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MaintenanceDesign



Indicator(s)


Modeling approach


Policy

The goal of CBM prognostics is to gain insights and support intomaking appropriate maintenance decisions. To enable this, a

maintenance policy should be incorporated into the prognosticimplementation process. Less mathematical models areapplicable to the situation of CBM compared to conventionalmaintenance policies.


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Determination of the Maintenance Policy

Based on a minimizing cost, maximizing availability, ormaximizing profit objective function, a maintenance policy canbe determined. The decision structure to come to an appropriatemaintenance policy is illustrated in below figure.


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RUL (Remaining Useful Life)The output of the selected prognostic model is theRUL. This RUL is considered as the input for

operations research decision making. The RUL is thetime interval between the actual point in timebetween obtaining the last data point and the pointin time where a failure occurs. This failure timediffers for a particular unit. Therefore, it is a randomvariable following a probability distribution.


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Condition Monitoring IntervalThe information on the monitoring interval can beused to update (fixed) intervals which areestablished in the design phase of a unit, or to usethe prognostic information for determining the timeuntil the next maintenance action. Conditionmonitoring can be done on continuous and onperiodic basis. In continuous monitoring, unit data

is collected on continuous basis and an alarm signalis triggered when a unit is operating outside of thenormal operating specifications.


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Delay TimeWithin delay time modeling (DTM) it is assumedthat failures occur according to a multi-phasedeterioration process. These phases can beclassified as representing the state in which the unitis operating according to specifications (i.e. good state), the state in which a deterioration can be

observed (i.e. the degraded state), and the unitcondition at which the unit is considered to be nomore functional (i.e. the failed state).


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Number of RenewalsRenewal theory is used to determine theaverage cost of a maintenance policy wherecomponents are assumed to be restored into anas good as new state. Within maintenancemodeling, replacing an item by a preventive

action and repairing an item by a correctiveaction are assumed to do so


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Expected Total Relevant Maintenance CostThe goal of an economic objective function is tominimize the expected total relevantmaintenance costs (E[TRMC]) per unit time.Under a CBM policy costs are built up from thefollowing cost factors (1) Costs for PM, (2) Costs

for CM (i.e. emergency costs), (3) Downtimecosts, (4) inspection costs.


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Maintenance ObjectiveIn order for companies to cope with a variety ofrisk factors, it is necessary to assign resources,

time and money in an optimal way. This meansoptimization of the maintenance policies.Quantitative maintenance modeling isconcerned with mathematical optimization ofprocesses with respect to cost or reliabilitycriterion.


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Determination of the Maintenance Policy Determine PolicyBased on the insights in the long term cost per unit timefor replacing an item with respect to a certainmaintenance objective, the time of maintenance can bedetermined for the unit. Based on the long term cost per

unit time, the CBM policy can be compared to aconventional maintenance policy using fixed replacementintervals. Application of a CBM program can result insavings due to extending the maintenance intervals andby preventing unexpected failures from ever occurring

due to the unit condition information. An appropriateway of determining the savings of implementing a CBMprogram would be determining the remaining service lifeof the component at the moment of replacement.


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CBM Key Step

1 Cost/Benefit analysis

2 Carry out equipment audit

3 Reliability & criticality audit

4 Select monitoring method

5 Select monitoring method

6 Data acquisition and analysis

7 Determine maintenance action

8 Review & measure effectiveness

Key Step toImplementConditionBasedMaintenance

f


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Cost Benefit Analysis

This will highlight where Condition BasedMaintenance will reduce costs Do we have life cycle cost info? What is cost of failures? What is cost benefit of avoiding failure?

d


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Carry out equipment audit

Make sure we have accurate databases withassets clearly identified and labeled The importance of this step is often overlooked Without clear identification of assets most activities

are compromised

l b l l d


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Reliability & criticality audit

Carrying out this means we can target the most important What Availability & Reliability does the business need?

MTTR Mean Time to RepairMTBF Mean Time Between Failure

FMEA Failure Modes and Effect Analysis

Select Appropriate Maintenance


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Select Appropriate MaintenanceStrategy

Selecting the appropriate combination ofmaintenance tasks depends on the failure history Initially the results from Step 3, Later on from feedback and analysis from Steps 6 8

S l i i h d


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Select monitoring method

We need to identify the best parameters to be measured todetect faults Fault and failure characteristics linked to measurable parametersand symptoms allow us to do this (Output from FMEA in step 3) We can then select the best measurement technique and thenselect the appropriate transducers and condition monitoringsystem

D i i i d l i


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Data acquisition and analysis

Quality of Measurements OK?

Possible errors come from- poor readings, transducer faults or adjacent machines. If confidence in readings low:

- take more readings or apply other types of CM Review symptoms, rules etc

D i i i


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Determine maintenance action

The key output of a CM program is recommendedmaintenance actions Poor feedback allows valuable information to leak away

M i Eff i


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Measuring Effectiveness

Managing CBM is a continuous process Technology & Techniques change Periodic reviewing the process is an important step


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Thank You

Documents

2 Condition Based Maintenance