RBI Introduction

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Module 01 - RBI Introduction

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INTRODUCTION TO RBI& API 580

RBI Training CourseModule 01

Scope of the Training

Introduction to RBI RBI Methodology Theory + with hands on exercises� Likelihood calculation � Consequence calculation

Case Study with the RBI software: refinery unit� Data preparation� Screening analysis� Detailed analysis

Agenda

Start End

1 09:00 12:3012:30 13:30

2 13:30 15:003 15:00 17:00

4 09:00 10:305 10:30 12:30

12:30 13:306 13:30 17:00

7 09:00 11:008 11:00 12:30

12:30 13:308 13:30 17:00

9 09:00 11:0010 11:00 12:0011 12:00 12:30

12:30 13:3012 Other Features 13:30 16:00

Lunch

Plant inspection plans Creating inspection plans from the RBI guidelines.Reporting features / information output Extracting information from software

Model creation and data entry issues.Detailed analysis - Data entry

Day 1Introductions - Installations, Introduction to RBI

Detailed analysis - Data entry

Day 4

Lunch

Project Start up and Data Organization. Inventory groups and Corr circuits

Module

Other limit statesDay 2

Consequence theory and exercises

RBI Training Program. Breaks assumed during the day but not shown. Timing approximate.

Item Objectives

Lunch

Likelihood theory 2

Likelihood theory 3 Other likelihood models

Thinning: calculation principles and inspection updatingLikelihood theory 1

Other features

Establishing criteria and using the IP tool Inspection Planning using risk criteria

Consequence theory

Model creation and data entry issues.Screening Analysis Introduction Using the screening tool

Lunch

Day 3

INTRODUCTIONS(Name, Organisationtype of work, why interested in RBI,English )

Presentation Topics - This Session

RBI History – API StandardsGeneral IntroductionThe benefits of RBIWhat RBI isHow RBI fits within existing plant systemsImplementing RBISome case studies

RBI History

Probabilistic risk analysis techniques� Started in the nuclear industry (1970s)

Quantitative risk assessment (QRA) in the Process Industries� Canvey Island and the Rijnmond Report (1980s)

Software tools for QRA� Eg DNV-Technica develops SAFETI and PHAST risk assessment

tools (1980s)ASME RBI principles overview document in 1991 API develops Risk Based Inspection Methodology (1990’s)� DNV main API sub-contractror� API Base Resource Document 581 (2000)� API RBI software� API RP 580 (2002)

RBI History

DNV develops ORBIT Onshore 1997-now� Some Reasons:

Need for a RBI software for all onshore installations– API 581 focuses on refineries

Improved consequence calculations with PHAST linkEnhancements in likelihood calculation

– ORBIT uses equations for limit state implementation

Need for a robust software architecture & professional software development and maintenance

� ORBIT is consistent with the API 580 RBI standard� ORBIT and API 581 share philosophy/technology

API RBI development by Equity Eng. (2002-now)API RP 581 Update (2008)API RP 580 Update (2009)

API Inspection and FFS Standards

Existing RBI & FFS documents

API750

API510

API570

API653

API - BRD P 581RISK BASEDINSPECTION

MPCFITNESS FOR

SERVICE

RBIAPI RP 581

FFSAPI RP 579

WorkingDocuments

Research & referenceDocuments

NewDocuments

ASME

RBI API RP 580

Presentation Topics - This Session

RBI History

General IntroductionThe benefits of RBIWhat RBI isHow RBI fits within existing plant systemsImplementing RBISome case studies

A Typical Plant

Loading facilities

Processing to give added value.

Storage and export

Typical Operating Objectives

Operate safely and profitably� Maintain high availability and throughput.� Minimize shut downs.� Extending shut down intervals� Prevent/reduce leaks.

Class question?

What are the typical plant objectives here?

Typical Plant Issues

Challenges� Old Plants� Large, complex units� Integrated Feed Systems� Many degradation mechanisms� Raw material price

PROCESS CORROSION

- Continuously degrading integrity

Corrosion Principles

Corrosion rate is measured as weight loss per unit area and is expressed in mils per year (mpy) or mm/y.Corrosion Rates can be affected by:� Passivity forming protective surface films (including

corrosion inhibitors, paints and coatings)� Oxygen content� Flow velocity/rates� Temperature� pH effects (Low and High)� Contaminants/intermediates

Some Corrosives Found In The Process Industry

WaterOxygenNaphthenic AcidPolythionic AcidChloridesCarbon DioxideAmmoniaCyanides

DepositsHydrogen ChlorideSulfuric AcidHydrogenPhenolsDimer and TrimeracidsOther

Low Temperature Corrosion

Below 500°F (<260°C)Occurrences� Inorganic compounds such as water, hydrogen sulphide,

hydrogen chloride, sulphuric acid, salts, etc.� Presence of water (even in very small amounts)� Electrolyte in hydrocarbon stream� Hydrocarbons in water streams creating acidic conditions � Solids .. Under deposit� Organic acids� Vapour Streams at water condensation points

Obeys electrochemical lawsStable films can reduce or prevent corrosion

Low Temperature Corrosion

From Process chemicalsFrom Process contaminantsNot caused by clean hydrocarbonsCaused by inorganic compounds such as water, hydrogen sulphide, hydrogen chloride, sulphuric acid, salts, etc.

High Temperature Corrosion

Above 500°F (>260°C)No water presentResult of a reaction between metal and process ions (such as oxygen O-, sulphur S, etc.)

High Temperature Corrosion

Important due to serious consequencesHigh temperatures usually involve high pressures.Dependent on the nature of the scale formed � General thinning� Localized thinning (pitting)� Inter-granular attack� Mixed phase flow

Metallurgical changes

Situations Leading To Deterioration

Normal operation, upset, startup /shutdown conditionsMaterial/Environment condition interactionsMany combinations of corrosive process streams and temperature/pressure conditions.In the absence of corrosion, mechanical and metallurgical deterioration can occur.Weather effects ….

Forms Of The Damage

General loss due to general or localized corrosionPitting attackStress Corrosion Cracking (SCC)Metallurgical ChangesMechanical damageHigh Temperature Hydrogen Attack (HTHA)

Damage types occur with specific combinations of materials and environmental/ operating conditions

SOHIC in soft base metal. Stress-Oriented Hydrogen Induced Cracking

In contrast to general corrosion, SCC is very hard to detect visually even when it has progressed to an extreme condition.

Stress Corrosion Cracking Detection

Types of Stress Corrosion Cracking

Chloride stress corrosion cracking (Cl-)NitratesCaustic stress cracking (NaOH)Polythionic acid stress corrosion crackingAmmonia stress corrosion cracking (NH4)Hydrogen effects (in steel)Sulfide stress corrosion cracking SSC, hydrogen induced cracking HIC, stress oriented hydrogen induced cracking SOHICHydrogen cyanide HCNOthers

High Temperature Hydrogen Attack (HTHA)

Carbon and low alloys steels exposed to hydrogen above 430°F (221°C)Hydrogen Partial pressure above 200 psi (>14 bar)Dissociation of molecular hydrogen to atomic hydrogen

H2 -> 2 H+Atomic hydrogen permeation into the steelReaction of atomic hydrogen with carbon in steelFormation of methane at discontinuitiesAPI 941 recommended for new installation

Longitudinal Weld

Magnification: 500x Etch: 2% Nital

High Temperature Hydrogen Attack

Metallurgical And Environmental Failures

Temper embrittlementLiquid metal embrittlementCarburizationMetal dustingDecarburizationSelective leaching

Grain growthGraphitizationHardeningSensitizationSigma phase885 F embrittlement

Mechanical Failures

Over pressurizationBrittle fractureCreepStress ruptureThermal shockThermal fatigue

Incorrect or defective materialsMechanical fatigueCorrosion fatigueCavitation damageMechanical damageOverloading

Conclusions

There are many causes of equipment failures in the process industry.Many are common and well documented.Other, less common deterioration mechanisms are not well documented.Deterioration is the result of metal and environment/ operating conditions combinations.These combinations vary somewhat in different process units.Detection and characterization of the different forms is a challenging and critical activity.

Tools exist to assist to assess the severity of corrosion or determine the appropriate materials of construction For Example:

NaOH Chart

These Tools Are Generally Used By Experienced Corrosion Engineers.

They can also be implemented in software as corrosion evaluation supplements

Determining Equipment Integrity

Requires information about the level of degradation:

� Monitoring (Fluid corrosivity) and� Inspection (Wall condition)

“MONITORING” POSSIBILITIES

Monitoring� Fluid Composition/Quality

Pressure, Temperature, pHContaminants when relevant

� Fluid corrosivityCorrosion probes (e.g. Weight loss, electrical resistance, linear polarization)

� Function of protective systems e.g. inhibitor injection

Inspection: Pressure boundary condition checks, e.g.� Visual examination� Thickness measurements� Other checks

Non Destructive Examination

- Inspection

Selecting Inspection method. Factors to consider

Type of defect� General metal loss� Localized metal loss� Pitting� Cracks� Metallurgical changes

Location of defect� On the outside wall of an item� The inside wall� Within the body of the wall� Associated with a weld

Selecting Inspection method. Factors to consider:

Material of construction� Magnetic� Non magnetic� Operating at high temperatures� Insulated

Equipment geometry:� May be hard to access� May require extensive activity e.g. scaffolding,

entry preparations, to perform the inspection

Many considerations when determining how to inspect.Also, need to justify the need for inspection.

NDE MethodsAmerican Society for Nondestructive Testing (ASNT)

Acoustic Emission Testing (AE) VolumetricEddy Current Testing (ET) Surface/ VolumetricInfrared/Thermal Testing (IR) SurfaceLeak Testing (LT)Magnetic Particle Testing (MPT) SurfaceNeutron Radiographic Testing (NR) VolumetricPenetrant Testing (PT) SurfaceRadiographic Testing (RT) VolumetricUltrasonic Testing (UT) VolumetricVisual Testing (VT) SurfaceMagnetic Flux Leakage (MFL)

Penetrant Testing

Penetrant solution is applied to the surface of a pre-cleaned component. The liquid is pulled into surface-breaking defects by capillary action. Excess penetrant material is carefully cleaned from the surface. A developer is applied to pull the trapped penetrant back to the surface The penetrant spreads out and forms an indication. The indication is much easier to see than the actual defect.

Magnetic Particle Testing

A magnetic field is established in a component made from ferromagnetic material.

The magnetic lines of force or flux travel through the material, and exit and reenter the material at the poles.

Defects such as cracks or voids are filled with air that cannot support as much flux, and force some of the flux outside of the part.

Magnetic particles distributed over the component will be attracted to areas of flux leakage and produce a visible indication.

Radiography Testing

X-rays are used to produce images of objects using film or other detector that is sensitive to radiation.

The test object is placed between the radiation source and the detector.

The thickness and the density of the material that X-rays must penetrate affect the amount of radiation reaching the detector.

This variation in radiation produces an image on the detector that shows the internal features of the test object.

Ultrasonic TestingHigh frequency sound waves are sent into a material by use of a transducer. The sound waves travel through the material and are received by the same transducer or a second transducer. The amount of energy transmitted or received, and the time the energy is received are analyzed to determine the presence and locations of flaws. Changes in material thickness, and changes in material properties can also be measured.

Ultrasonic Principles

Straight Beam(Longitudinal Wave)

Angle Beam(Shear Wave)

Ultrasonic Presentations

TOP VIEW(C-SCAN)

END VIEW(B-SCAN)

SIDE VIEW(D-SCAN)A-SCAN

Risk Based Inspection

Presentation Topics

General Introduction

The benefits of RBIWhat RBI isHow RBI fits within existing plant systemsImplementing RBISome case studies

The Value of RBIWhat is the first duty of Business?

“The first duty of business is to survive, and the guidingprinciple of business economics is not the maximisation of profit - it is the avoidance of loss.”

Peter Drucker

The Key Benefits of an RBI Study

Identify the high risk itemsUnderstand the risk drivers and develop mitigation plansFocussed inspection plans which:� Increase safety and reduce risk� Help to improve reliability� Often results in cost benefits due to:

Reduced turnaround time and/orA reduction in the number of items to be inspectedThe associated “maintenance” costs e.g access arrangements

Normally an overall reduction in risk and cost savings from the inspection activity.

Presentation Topics

General IntroductionThe benefits of RBI

What RBI isHow RBI fits within existing plant systemsImplementing RBISome case studies

What Is RBI?

A method/process for prioritizing equipment for inspection based on risk.It determines the risk associated with the operation of specific items of equipment and identifies the key factors driving the risk.A tool which demonstrates the value (or not) of performing specific inspection activities.It is a decision making management tool applied to the issue of Inspection Planning.

Equipment Types

•Pressure Vessels—All pressure containing components.•Process Piping—Pipe and piping components.•Storage Tanks—Atmospheric and pressurized.•Rotating Equipment—Pressure containing components.•Boilers and Heaters—Pressurized components.•Heat exchangers (shells, floating heads, channels, and bundles).•Pressure-relief devices.

Strategic Process� Increasing reliability (revenue)

� Lowering cost

� Lowering risk

Integrated Methodology� Risk factors

Likelihood

Consequence

Supports effective decision making

Risk Based Inspection

What Constitutes an Undesirable Event In RBI?

Failure is defined as a leak of the equipment contents to the atmosphere; “breach of containment” or LOPC� Heat exchanger failures are channel or

shell leaks.� Pump failures are due to seal leaks and

adjacent piping fatigue cracking.

RBI_Key_Concepts.vsd

Risk = Likelihood of Failure XConsequenceof Failure

GFF DFx

Age

DamageType/Rate

InspectionEffectiveness

Damage Area.

Equip. Repair

Other repairs

Injury

Business Int.

x

Abbreviations: :

DF: DamageFactor

GFF: Generic FailureFrequency

Fi : Process, Mechanical& Universal Factor

Fdomino:Domino Eff.FactorMF: Management Factor

xMF Fp x Fm x Fu

RBI - Detailed Analysis

Components in the calculation of the risk

Fdomino x CoF

Common Damage Mechanisms in RBI

DamageMechanisms

InternalThinning

Stress CorrosionCracking

External Damage

Brittle Fracture

PipingFatigue

HTHA Lining PRVs

General• HCl

• HT Sulfide .& Nap. Acid

• HT H 2S/H2

• H2SO 4

• HF

• Sour Water

• Amine

• HTOxidation

• Caustic

• Amine

• SSC

• HIC/SOHIC

• Carbonate

• PTA

• ClSCC

• HSC-HF

• HIC/SOHIC-HF

Cl SCC

CUI

Damage factor CalculationMANUAL ACTIVITY

Estimate the likelydamage state /

severityConsider data source

Assess theinspection history(Effectiveness)

Inspection Effectiveness

Determine the Likelihood of being in oneof the different possible damage states:

1 No worse than predicted X %

2 Up to 2x worse than predicted Y %

3 Up to 4x worse than predicted Z %

Damage states

Calculate the failure frequency for eachstate using the relevant limit state

equation

Calculate the weighted failure frequencyfor the item based on the Likelihood of

being in the different states.

Steps in Bayes_LoF

CALCULATING THE FAILURE FREQUENCY

Failures only occur when the rate of degradation is

higher than expected.

Undesirable Consequences in RBI

HEAT from flames destroys equipment, injures people

PRESSURE WAVE from explosions knocks down structures and people, causes flying objects

TOXIC cloud, for some duration, causes toxic exposure injuries

ENVIRONMENTAL DAMAGE due to spill (currently only included in AST RBI software)

Consequence Calculation

Physical Properties

Process Information

Equipment Damage Costs

Business Interruption Costs

Calculate Release Rate or Release Mass

Equipment Information

Safety Costs

Assessment of Incident Outcome

Damage Areas

Amount of Effort - RBI vs QRA

QRA*

RBI**

Likelihood Consequence

* Quantitative Risk Assessment ** Risk Based Inspection

Input Data For A Quantitative RBI Assessment

For some damage mechanisms, e.g. SCC, brittle fracture, fatigue, other data may be needed e.g. PWHT, Charpy test temp.

What has been looked for and what has been found

Is it operating as intended?

Identify all items

The main input data collected

ItemOD Tnom Matl Ins Press Temp Fluid Temp. Press Fluid Mechanism Severity/rate Done? Result?

A Thinning, SCC, Furnace, HTHA,..

BC

Inspection dataDesign Data Operating Data Damage mechanisms

What do we expect to find and what at what severity?

RBI Results?

Why -(Damage mech. &factor)

Where / How -(Item - Effectiveness - Material - Mechanism)

When -(Basis Inspection planning targets.)

What -(Risk priority)

Item no.

Type From To Damage Mechanism

GFF DF LoF CoF Risk Insp. Type

Insp. Date

New DF

1 Pipe Thinning 30002 Vessel CUI 1003 Fin Fan Erosion 0.5

Calculation of the risk with a lookahead: Inspection Plan

5

4

3

2

1

High RiskMedium-High Risk

Med. High Risk

Medium Risk

Low Risk

Lik

elih

ood

Cat

egor

y

Consequence CategoryA B C D E

The Presentation Of Risk

A B C D EConsequence of Failure

Like

lihoo

d of

Fai

lure

A

C

B

How Will This Picture Change With Time?

Risk Increase Over Time

Likelihood of failure will increase over time because of time-dependent material degradation

A B C D EConsequence of Failure

Like

lihoo

d of

Fai

lure

What is the effect of Inspection ?

A B C D EConsequence of Failure

Like

lihoo

d of

Fai

lure

Steps Leading To The Inspection Plan

Risk Criteria

High Risk

Negligible risk

Unacceptable region

The ALARP or Tolerabilityregion(Risk is undertaken only ifa benefit is desired)

Broadly acceptable region(No need for detailed working todemonstrate ALARP)

Risk cannot be justifiedsave in extraordinary

circumstances

Tolerable only if risk reduction isimpracticable or if it cost is grossly

disproportionate to the improvementgained

Tolerable if cost of reduction would exceed the improvement

Necessary to maintain assurancethat risk remains at this level

Traditional Vs. Risk-Based Inspection Planning

TraditionalInspection based on experience (usually by previous leaks and breakdowns)

Inspection effort driven by “Likelihood of failure”

Reactive “fire fighting”, running behind the ball

Use of appropriate / Inappropriate NDT techniques

RBIInspection based on experience and systematic (risk) review

Inspection effort driven by “risk”, i.e. Likelihood of failure and consequences of failure

Pro-active planning and execution of inspections

Systematic identification of appropriate NDT techniques

Change inspection frequencies (when)

Change inspection scope / thoroughness (what)

Change inspection tools / techniques (how)

Inspection Program Options for Influencing Risk

RBI - Applications

Risk-prioritized Turnaround planning� High safety/reliability impact = more attention (in order to

lower risk� Less impact safety/reliability = less attention (in order to

lower costs)� Result:

Lower equipment life cycle costsFewer incidents / outagesFewer unnecessary inspectionsHigher reliability

May also assess the impact of delaying a turnaround/ shut down

RBI - Applications

Special focus studies e.g.:� Corrosion under insulation.� Positive material identification.� Hydrogen sulfide etc.

What if studies e.g.� Assess the impact of process changes.� Assess the impact of a different feed.

Can RBI Help To Prevent All Releases?

MechanicalFailure

43%

Process Upset11%

Sabotage/Arson1%

Unknown14%Operational

Error21%

Design Error5%

Natural Hazard5%

About half of thecontainmentlosses in a

typicalpetrochemicalprocess plant

can beinfluenced by

inspectionactivities

Where Inspection Can Help

Source: Large Property Damage Losses in the HC-Chemical Industries - A thirty year review, 17th edition, J&H Marsh& McLennan.

THE SYSTEM FACTORS

"HARDWARE" "SOFTWARE" PEOPLE

Managing Risk - Considerations

Risk Exposures (Potential Losses)

Experienced Losses - Cause and Costs

0

50

100

% a

nd

MM

$

Percentage

Avg. $ loss

Percentage 43 21 14 11 5 5 1

Avg. $ loss 72.1 87.4 68.9 81 55.7 82.5 37.1

Mech. Fail.

Operator error

UnknownProcess upsets

Natural hazards

Design errors

Sabotage/arson

Source: Large Property Damage Losses in the HC-Chemical Industries - A thirty year review, 17th edition, J&H Marsh& McLennan.

The Equipment Involved

Losses vs Equipment Type

0

50

100

% a

nd

MM

$

% of losses

Avg. $ loss

% of losses 33 15 10 8 8 7 5 5 5 2 2

Avg. $ loss 76.9 61.9 151.8 86.9 68.1 38.9 69.6 60.6 34.6 82.4 16.3

Piping TanksReactors

Towers

Pumps/Com

Drums

Heat exch.

Unknown

Misc.Vesse

lsHeater

s

Presentation Topics

General IntroductionThe benefits of RBIWhat RBI is

How RBI fits within existing plant systemsImplementing RBISome case studies

Managing Integrity

Trained and Competent Staff

PlantIntegrity

Plant DesignOperating &MaintenanceProcedures

Data

Dataanalysis

Management SystemNormally fixed.

RBI projectprocedures. Data Integrity is

essential!

Trained staff areneeded.

Cannot beneglected!

Model For An MI System

SystemDocumentation

(Say what you do)

Documentation/Records

(Document the actions)

Actions(Do what you say)

FILING SYSTEM:

Asset RegisterDesign data

MI equipmentInspection dataOperational dataDeficiency data

Inspection PlansRepair information

Defect AssessmentsInspection due dates

TOP LEVELSYSTEM

DOCUMENTS

GENERALPROCEDURES:

WORKINSTRUCTIONS

STANDARDS

ESTABLISHSYSTEM

INSPECT

UPDATE/REVISE PLANS:

ASSESS THERESULTS

PLANNING

RBI

The Integrated Plan

INSPECTION PLANNING

06_Inspection Planning RBI role.vsd

The InspectionPlan

Database

Corporate Philosophy

Local Legislation

Corporate Policy

Inspection Planning activity

i. Inspectii. Onsite assessment

iii. Detailed FfS ifneeded

Update database

Codes andStandards, RP's,

RAGAGEPM

onito

ring

info

.

Gen

eral

"G

ood

Hou

se k

eepi

ngfin

ding

s

RB

I ana

lysi

s/pr

iotit

izat

ion

Data analysis

Design

InspectionOperation

Construction

DM's

Anomalies

Presentation Topics

General IntroductionThe benefits of RBIWhat RBI isHow RBI fits within existing plant systems

Implementing RBISome case studies

Typical RBI implementation

Define scope of RBI StudySet up RBI team and train

Collect Data

Identify inventory groups (For consequences)Identify Corrosion circuits

Perform Screening Analysis

Select high risk equipment items for Detailed AnalysisPerform detailed RBI analysis � Consequence data-Likelihood data

� Run risk assessment & Review the results

� Develop action criteria� Discuss Orbit proposed inspection guidelines and run final

Translate into an actual inspection plan with schedule

Implement plan-perform inspectionsUpdate the model with latest inspections

Risk Target and Inspection Planning

Inspection Target

Ris

k / D

amag

e F

acto

r (D

F)

Predicted Risk Increase

Now

Time to next inspection

Highly Effective

Risk / DF

1st

Turnaround

Fairly Effective

2nd

Turnaround

Time

Implementation Timeline (Tight Deadlines)

Equipment Data Collection

Risk Analysis and Prioritization

Inspection Program Improvements

Weeks 2 4 6 8

EffortEvergreen

Level of Effort

Critical Success Factors

Defined objectives and planningA robust working process to assure efficiency and quality A good knowledge of the RBI theoryTrained competent staffA good understanding of the tools to be used.“Evergreening” the process.

Types of Analysis

A qualitative unit analysis (API 581 for Plant Units)� Which unit or platform should be the first based on risk

A system screening analysis� Which piping systems need to be included

A qualitative circuit based analysis A qualitative equipment analysisA semi-quantitative circuit based analysisA semi-quantitative equipment based analysisA fully quantitative equipment based analysis.

THE STEPWISE APPROACH

Will be of most benefit to a large facility just starting on the journey.

This course introduces the semi-quantitative approach but focuses on the quantitative.

These steps may beformal or informal.

System Screening- Determine which systems to be included

Semi-quantitative analysis of theincluded equipment

Quantitative analysis ofhigh risk items

FfS/ CBAof a few.

Facility Screening- Determine where to start the study

Vision for the RBI Services.vsd

Qualitative vs Quantitative - COST COMPARISON

For repeat analyses the quantitative approach is far more efficient.The benefits multiply with time

MethodEst. total

hoursHours on

Accum. Hours

"Value"

Data Coll. Analysis Insp. plan insp plan

Qual. 310 10% 40% 50% 155 na 40

Quant 500 60% 10% 30% 150 na 100

Qual. 310 10% 40% 50% 155 620 40

Quant 200 15% 15% 70% 140 700 100

Second time around:

Initial Analysis

Activity

Proportion of the time spent on activity:

ADVANTAGES OF THE QUANTITATIVE APPROACH

Not simply opinion based-easily reproducibleAccuracy-Time model� The results of qualitative and semi quantitative studies are

frozen in time. In reality the risk will change as the equipment ages and as new data is available from inspection. The quantitative method incorporates this.

What if studies, e.g.:� New campaigns in swing plants � If the study had been done qualitatively or semi

quantitatively, the effort would be much higher� i.e. It is more efficient and powerful to use an analytical

approach

Presentation Topics

General IntroductionThe benefits of RBIWhat RBI isHow RBI fits within existing plant systemsImplementing RBI

Some case studies

Issue:

Should we change our feed to a cheaper but more corrosive alternative?

What does this mean for our risks and inspection requirements?

EXAMPLE STUDY 1

Risk

Inspection Interval

Corrosive Conditions

Tolerable Risk

Maximum Tolerable Risk

Changed Inspection Frequency

Unacceptable Risk

Standard OperatingConditions

Example Study 1

Financial Risk Exposure

$34,793

$46,846

$26,421$15,000

$25,000

$35,000

$45,000$55,000

$65,000

0.1% 0.5% 0.8%

Corrosive in the feed

Fin

anci

al R

isk

afte

r In

spec

tion

($ p

er y

ear

per

equi

pmen

t it

em)

Example Study 1

Cost of Inspection

$0$50,000

$100,000$150,000$200,000$250,000$300,000$350,000

0.1% 0.5% 0.8%

% Corrosive in Process Feed

Cos

t of

Ins

pect

ion

Example Study 1

The study gave the facility the information on:� The increased risk exposure � The increased cost of inspection

They compared this with the cost benefits of the cheaper feed and made their decision.

Example Study 1

-$400,000

-$200,000

$0

$200,000

$400,000

$600,000

$800,000

$1,000,000

$1,200,000

$1,400,000

Unit 30 Unit 33 Unit 34 Unit 48 Unit 51

Current Inspection CostsCurrent Maintenance CostsTotal Current CostsRBI Inspection CostsRBI Maintenance CostsRBI TotalTotal Savings

Example Study 2

Inspection

Maintenance

Total

Savings

RBICurrent

$0

$500,000

$1,000,000

$1,500,000

$2,000,000

$2,500,000

$3,000,000

COST BENEFIT ANALYSIS Results for all Units

Example Study 2

Cost effective decision making for an older refinery with a limited inspection history.

Example Study 3

Using The Financial Risk Values

Total Risk vs. Risk RankRefinery Process Unit, Top 10% Risk Items

$0

$200,000

$400,000

$600,000

$800,000

$1,000,000

$1,200,000

$1,400,000

0 10 20 30 40 50

Risk Rank

Ris

k,$/

yr Total Risk = $11,500,000/year

Assess The Cost Benefits Of Inspection

Total R isk vs . R isk RankRe finery Process Unit, Top 10% Risk Items,

Same Ite ms, Each with 1 M ore Inspe ction

$0

$200,000

$400,000

$600,000

$800,000

$1,000,000

$1,200,000

0 10 20 30 40 50

Ris k Rank

Ris

k, $

/yr

Total Risk = $4,100,000/yr,

Savings = $7,400,000/yr

Cost = $250,000 (mostly piping, approximately $5,000 avg. insp. cost)

The Risk of the Lowest 10% Items

Total Risk vs. Risk RankRefinery Process Unit, Bottom 10% Risk Items

$0

$200

$400

$600

$800

$1,000

$1,200

$1,400

$1,600

0 10 20 30 40 50

Risk Rank

Ris

k, $

/yr

Total Risk = $12,000/yr

The Inspection Benefits Here

Total R is k vs . R is k R ankR e fine ry Proce s s Unit, B ottom 10% R is k Ite ms ,

Same Ite ms , Each with 1 M ore Ins pe ction

$ 0

$ 20 0

$ 40 0

$ 60 0

$ 80 0

$ 1 ,00 0

$ 1 ,20 0

0 1 0 2 0 3 0 4 0 5 0

Ris k Rank

Ris

k, $

/yr

Total Risk = $4,300/yr,

Savings = $7,700/yr

Cost = $250,000 (mostly piping, approximately $5,000 avg. insp. cost)

END