RAM Modelling in the RAM Modelling in the Project Design PhaseProject Design Phase

Friday 30Friday 30thth April, 2010 April, 2010

Paul WebsdanePaul Websdane

Reliability Modelling Reliability Modelling for Business for Business

DecisionsDecisions

Asset Management Council – WA Chapter & Maintenance Engineering Society of Asset Management Council – WA Chapter & Maintenance Engineering Society of AustraliaAustralia

RAM Modelling for Business RAM Modelling for Business DecisionsDecisions

• Project Design and Execute PhasesProject Design and Execute Phases– Steps in Process.Steps in Process.– Examples & Learnings.Examples & Learnings.– Benefits.Benefits.

• RAM in Operations phaseRAM in Operations phase– Barriers & Benefits.Barriers & Benefits.

IntroductionIntroduction

– Snr Reliability Engineer – K2 Technology.Snr Reliability Engineer – K2 Technology.– Experience in Oil and Gas, Alumina, Experience in Oil and Gas, Alumina,

Mining, Condition Monitoring, Pumping.Mining, Condition Monitoring, Pumping.– RAM Tools & Packages;RAM Tools & Packages;

•Many different packages are available.Many different packages are available.

•Each have strengths and weaknesses.Each have strengths and weaknesses.

– Used RAM for analysis of large new Used RAM for analysis of large new projects, small design changes, tank projects, small design changes, tank overhaul scenarios, decisions on overhaul scenarios, decisions on redundancy.redundancy.

RAM Modelling OverviewRAM Modelling Overview

• Tool to analyse and predict the availability / Tool to analyse and predict the availability / reliability of an asset or facility.reliability of an asset or facility.

• Reliability Block Diagrams (RBD) used.Reliability Block Diagrams (RBD) used.

• Use Equipment Capability & Reliability data. Use Equipment Capability & Reliability data. • Maintenance Strategies & Schedules Maintenance Strategies & Schedules

(optimise).(optimise).

• Overall production impact - $$$$.Overall production impact - $$$$.

• Improved business decisions. Improved business decisions.

RAM models in the Design RAM models in the Design PhasePhase

• Evaluate, Validate and Optimize designEvaluate, Validate and Optimize design– Availability & Reliability targets.Availability & Reliability targets.– Production capability.Production capability.– Bottlenecks & Big hitters – Critical Equipment.Bottlenecks & Big hitters – Critical Equipment.– Redundancy levels.Redundancy levels.– Sparing.Sparing.

• Can “Design In” ReliabilityCan “Design In” Reliability– Focus improvement efforts early in design.Focus improvement efforts early in design.

Model Basic StepsModel Basic Steps

• Understand system operating context, Understand system operating context, production impact and cost of downtime.production impact and cost of downtime.

• Document assumptions.Document assumptions.

• Build the RBD and Reliability Data Register.Build the RBD and Reliability Data Register.

• Populate with Reliability Data and details of Populate with Reliability Data and details of Maintenance Strategy / Shutdowns.Maintenance Strategy / Shutdowns.

• Analyse the System.Analyse the System.

• Update and refine over time.Update and refine over time.

• Conduct Sensitivity analyses.Conduct Sensitivity analyses.

Reliability Block DiagramsReliability Block Diagrams

• Build Reliability Block Diagram from Build Reliability Block Diagram from P&ID, system drawings, PFDs;P&ID, system drawings, PFDs;– RBD’s represent the connections RBD’s represent the connections

between system components from a between system components from a reliability perspective. reliability perspective.

– Does not show process flow.Does not show process flow.

Reliability Block DiagramsReliability Block Diagrams

3 x 50%

2 x 100%

RBD’s – ExamplesRBD’s – Examples

Operating Context – what we Operating Context – what we needneed

• Design Capacity of each block.Design Capacity of each block.• Redundancy.Redundancy.• Impact on productionImpact on production

– No impact – why in the model?No impact – why in the model?

• Single Point Vulnerabilities! Single Point Vulnerabilities! – Very important – do not miss these.Very important – do not miss these.

• Bypass capacity on failureBypass capacity on failure– Inbuilt work arounds that protect Inbuilt work arounds that protect

production.production.

Production ImpactProduction Impact

Full Production

32 kT/d

Each Turbine

8 kT/d

For full production system requires 4 turbines online at all

times (32kT/d)

Production ImpactProduction Impact

Full Production

30 kT/d

Each Pump

15 kT/d

For full production system requires 2 pumps online at all

times (15kT/d)

Production ImpactProduction Impact

• Bypass capacity – refines model with Bypass capacity – refines model with actual production impact – also helps actual production impact – also helps with buy in from operations.with buy in from operations.

• Must understand the linkages Must understand the linkages between key elements in the model.between key elements in the model.

Failure Modes / Reliability Failure Modes / Reliability Data Data

• Understand dominant functional Understand dominant functional failures.failures.

• Reliability data sourced fromReliability data sourced from– CMMS & Facility Operating History.CMMS & Facility Operating History.– Experienced operators.Experienced operators.– OREDA.OREDA.– Vendor.Vendor.

Reliability Data Reliability Data

• CMMSCMMS– Maintenance and failure history.Maintenance and failure history.– Data accuracy? Job recording?Data accuracy? Job recording?– How accurate is this across industry?How accurate is this across industry?– Be careful – garbage in , garbage out.Be careful – garbage in , garbage out.

• Facility Operating / Trip historyFacility Operating / Trip history– Often stored outside CMMS.Often stored outside CMMS.– See your friendly Reliability Engineer.See your friendly Reliability Engineer.

Reliability Data Reliability Data

• Operators & Maintenance ResourcesOperators & Maintenance Resources– Very valuable information resource.Very valuable information resource.– BUT – difficult to quantify losses without BUT – difficult to quantify losses without

data.data.– Useful information on Bypass capacity.Useful information on Bypass capacity.– Engage operations and maintenance Engage operations and maintenance

where possible.where possible.

Reliability Data Reliability Data

• Vendors and OREDAVendors and OREDA– Some vendors have good history – check Some vendors have good history – check

operating context and environment.operating context and environment.– OREDA is of use – ensure a reasonable OREDA is of use – ensure a reasonable

population of equipment is available.population of equipment is available.

• Useful Reliability Data is available – Useful Reliability Data is available – understand limitations and use with understand limitations and use with care.care.

Reliability Data RegisterReliability Data Register

Compressor Critical_Failure OREDA Critical Mean 0 3.2 1 22.8 1

Compressor_Motor Critical_Failure OREDA Critical Mean 0 2.12 1 47.5 1

Compressor Critical_Failure OREDA Critical Mean 0 3.2 1 22.8 1

Compressor_Motor Critical_Failure OREDA Critical Mean 0 2.12 1 47.5 1

Refrigerant_Air_Dryer Critical_Failure Spurious Trip 0 0.67 1 48 1

Refrigerant_Air_Dryer Critical_Failure Spurious Trip 0 0.67 1 48 1

Vessel Critical_Failure Significant External Leak 0 60 1 12 1

Maintenance

MTTR (hrs) CVFailure ModeDescription

Bypass Capacity (%) MTTF (years)Maintainable Component

MCFailure Mode

Nameb

RELIABILITY DATA

Air_CompA_NRB Air Compressor A 1/01/2017 50

Air_CompB_NRB Air Compressor B 1/01/2017 50

Dessicant_Air_DryerA_NRB Dessicant Air Dryer A 1/01/2017 50

Dessicant_Air_DryerB_NRB Dessicant Air Dryer B 1/01/2017 50

Inst_Air_Receiver_NRB Instrument Air Receiver 1/01/2017 50

Capacity (kT/d)Start dateS-unit Description• Capture key data & Capture key data & references.references.

• Hold workshop with Hold workshop with operations & operations & maintenance to maintenance to validate / review validate / review data & assumptions.data & assumptions.

Analyse the Model OutputsAnalyse the Model Outputs

• Model outputs – typical.Model outputs – typical.

RAM Model ResultsReliability %

(Unplanned Losses)

Reliability % 98.07

Unreliability % 1.93

Total Annual Downtime Equivalent (Days) 7.0

Total Annual Downtime Equivalent (Hours) 168.9

RAM Model Results Availability % (Unplanned + Planned Losses)

Availability % 96.38

Unreliability % 3.62

Total Annual Downtime Equivalent (Days) 13.2

Total Annual Downtime Equivalent (Hours) 317.1

Capacity Level %

% Time at Capacity Level

Days at Capacity Level per

year

0% 0.63 2.31

0% - 33.3% 0.00 0.00

33.4% - 66.6% 0.2 0.68

66.7% - 99.9% 7.0 25.53

100% 92.19 336.48

Model Outputs - timeModel Outputs - timeFacility XYZ Availability over time

93.00%

94.00%

95.00%

96.00%

97.00%

98.00%

99.00%

100.00%

2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031

Model OutputsModel OutputsFacility - Relative Unreliability

67.00%

12.01%

6.57%

6.56%

3.52%

2.52%

1.83%System A System B

System C System D

System E System F

System G

Unit InterventionsUnit InterventionsFacility XYZ - Unit Interventions - Field Life

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10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

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Corrective Interventions

Preventive Interventions

Unit InterventionsUnit Interventions

Facility XYZ - Subsystem A - Unit Interventions per year

0

5

10

15

20

25

30

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2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033

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Corrective Interventions

Preventive Interventions

Update and Refining the Update and Refining the ModelModel

• Assess Design ChangesAssess Design Changes– Latest updates.Latest updates.– Quantify improvements .Quantify improvements .– Incorporate maintenance (RCM).Incorporate maintenance (RCM).

• Shutdown analysis.Shutdown analysis.

• Sensitivity Studies.Sensitivity Studies.

• Production Profiles.Production Profiles.

Design ChangesDesign Changes

• Add newer component (high Add newer component (high reliability)reliability)– System availability before – 98.0%System availability before – 98.0%– System availability after - 99.2%System availability after - 99.2%

• Improvement of 1.2% or 4.4 days Improvement of 1.2% or 4.4 days productionproduction

@ $1million per day = $4.4m savings@ $1million per day = $4.4m savings

Design ChangesDesign Changes

• Redesign to save cost!Redesign to save cost!

• Reduction in availability 0.5% or 1.8 Reduction in availability 0.5% or 1.8 days productiondays production

@ $1million per day = $1.8m COST @ $1million per day = $1.8m COST to business.to business.

• Can demonstrate impact of changes Can demonstrate impact of changes on facility performance – better on facility performance – better decisions are made.decisions are made.

Sensitivity StudiesSensitivity Studies

• Critical Equipment improvement Critical Equipment improvement options;options;– water washing frequencies.water washing frequencies.– more reliable equipment.more reliable equipment.– maint strategy changes.maint strategy changes.– Redundancy installed.Redundancy installed.

• Show me the money $$$$!Show me the money $$$$!• Shutdown analysis – modify Shutdown analysis – modify

frequency and durations – optimise.frequency and durations – optimise.

Sensitivity Studies – Savings Sensitivity Studies – Savings $$$$

Facilty XYZ Reliability Study

Impact of variations to design for Prod Water

and Recovered Oil Systems

Scenario ModelRecovered Oil Pump

Degasser Water Pump

Produced Water

CentrifugeAvailability Comments

0 Base 2 x 100% 2 x 100% 2 x 100% 98.00% Base Case1 1a 2 x 100% 2 x 100% 2 x 100% 98.15% New Assumptions added2 1b 2 x 100% 2 x 100% 1 x 100% 97.81% Removed Centrifuge3 2a 2 x 100% 3 x 50% 2 x 100% 98.25% Added 3rd Degasser Water Pump4 2b 2 x 100% 3 x 50% 1 x 100% 97.89% Removed Centrifuge5 3a 2 x 100% 2 x 50% 2 x 100% 97.00% Worst Case - 2 x 50% Degasser Water Pumps6 3b 2 x 100% 2 x 50% 1 x 100% 96.25% Worst Case - 1 Centrifuge

Mud Thickener Descale Scenarios

Shutdown Frequency

(wks)

Shutdown Duration (days)

AvailabilitySavings ($)

per yearfrom Base Case

Base Case - Current condition 25 10 94.29%Scenario 1 - short life, short turnaround 15 7 93.33% 347,619-$

Scenario 2 30 11 94.76% 173,810$

Scenario 3 40 15 94.64% 130,357$ Scenario 4 - long life, longer turnaround 60 25 94.05% 86,905-$

Sensitivity Studies – Savings Sensitivity Studies – Savings $$$$

Sensitivity Study - Facility XYZfrom base case ($m)

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

A B C D E

Option

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Production Profiles - Production Profiles - RefiningRefining• Highlights system deficiencies over time.Highlights system deficiencies over time.

• ApplicationsApplications– well deterioration over time.well deterioration over time.– Tank volume decrease (scaling) over time.Tank volume decrease (scaling) over time.

Well Production Profile vs Capacity - XYZ

0

10

20

30

40

50

60

2016 2018 2020 2022 2024 2026 2028 2030 2032 2034

Pro

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Well Production Profile

Max capacity

Improving Business Improving Business DecisionsDecisions• Predict performance over time.Predict performance over time.• Validate design changes.Validate design changes.• Quantify ($) cost and impact of failure.Quantify ($) cost and impact of failure.• Identifies Critical Equipment Identifies Critical Equipment

– where to focus improvement efforts.where to focus improvement efforts.– where to focus training.where to focus training.– where to consider redundancy.where to consider redundancy.– where to hold critical spares (MTTR).where to hold critical spares (MTTR).

Asset’s Operations PhaseAsset’s Operations Phase

• Traditionally this is done poorly Traditionally this is done poorly (if at all).(if at all). • BarriersBarriers

– Lack of buy in / support from operations & Lack of buy in / support from operations & maintenance .maintenance .

– involve O&M in model build and involve O&M in model build and assumptions.assumptions.

– Modelling – inaccuracy, no understanding of Modelling – inaccuracy, no understanding of operating context.operating context.

– Rigorous review of data and facility Rigorous review of data and facility configuration – engage operations.configuration – engage operations.

Asset’s Operations PhaseAsset’s Operations Phase

• BarriersBarriers– Lack of confidence in model / data.Lack of confidence in model / data.– Use valid data, document assumptions, Use valid data, document assumptions,

involve operations & maintenance.involve operations & maintenance.

• Review actual performance compared Review actual performance compared to design over time – feedback into to design over time – feedback into model.model.

• Consider the model to be “live” – Consider the model to be “live” – regularly update to improve accuracy.regularly update to improve accuracy.

Operations Phase - BenefitsOperations Phase - Benefits

• Highlight improvement opportunities.Highlight improvement opportunities.

• Justify cost of upgrades.Justify cost of upgrades.

• Quantify BENEFITS of past projects.Quantify BENEFITS of past projects.

• Assess effectiveness of maintenance.Assess effectiveness of maintenance.

• Assess risk of shutdowns – optimize Assess risk of shutdowns – optimize shutdown intervals.shutdown intervals.

SummarySummary

• RAM modelling is a valuable tool in RAM modelling is a valuable tool in Reliability Engineering.Reliability Engineering.

• Important to use valid data and involve Important to use valid data and involve operations & maintenance.operations & maintenance.

• Useful in all industries, for large and Useful in all industries, for large and small projects.small projects.

• Can improve business decisions by Can improve business decisions by quantifying loss and benefits in quantifying loss and benefits in $$ terms.terms.

Questions?Questions?