RAM PIPE REQUAL: A Risk Assessment & Management Based Process for the Requalification of Marine Pipelines

Robert Bea Marine Technology & Management Group

University of California at Berkeley bea@ce.berkeley.edu

mailto:bea@ce.berkeley.edu

Topics

RAM PIPE REQUAL

Reliability Approach

Level 2 examples: corrosion

Un-instrumented

Instrumented

RAM PIPE REQUAL Project

Develop guidelines for requalification of marine pipelines

Associated Developments RAM PIPE REQUAL

Guidelines Project

RAM PIPE REQUAL special projects

API RP 1111 LSD SECTION 17

OTHER ASSOCIATED PROJECTS

RAM Workshop

Rosen reliability formulations

PEMEX requal criteria

PIMPIS

PIPE IMR

Trinidad Pipelines Time Pf's

DNV RP F 101

ABS GL

HSE OTO 99 002

CFER PIRAMID

RAM

MARINE SYSTEM Design

Construction

Decommissioning

Operation Maintenance

ASSESSMENT

MANAGEMENT

RISK

Risk Assessment

Risks: likelihoods & consequences

Hazards: uncertainties, threats

Knowable & unknowable hazards

Assessment: identify & evaluate

Alternatives:likelihoods, consequences, both Observe: improve & revise

Risk Management

Alternatives: evaluate, costs, benefits Culture: production & protection

Identify: alternatives

Resources: abilities, money, time

Implementation: plan, organize, lead, control

Revise: monitor, assess, modify

Accidents are caused by people and so are successes

High Consequence Accidents

Environment (intrinsic)

Human (extrinsic)

80 %

Design Construction Operations

80 %

Organizations have major influences

PROPAGATING EVENTS

Organization Errors - 80 % Other Factors - 20 %

CONTRIBUTING EVENTS

Organization Errors - 80 % Other Factors - 20 %

INITIATING EVENTS

Individuals errors of: omission - 20 % commission - 80 %

Near Misses Accidents

Primary factors

Interfaces

Operators

Procedures

HardwareStructure

Organizations

Environments

REACTIVE empirical

pproaches frequent accidents

REAL-TIME PROACTIVE actionpredictive

frequent andinfrequent infrequentaccidents accidents

before & after UNSAFE SPACE

A

Three key strategies

Reduce the likelihood of HOE

Increase detection & remediation of HOE

Reduce the effects of HOE

Quality, safety, & reliability

QUALITY ability to satisfy requirements

Serviceability use for purpose for conditions

Safety acceptability of risks

Compatability acceptability of impacts

Durability freedom from unanticipated

degradation

S T A RT

S e l e c t P i p e l i n e F o rC o n d i t i o n E v a l u a t eA s s e s s m e n t& S u r v ey R e s u l tsR e q u a l i f i c a t i on

L E V E L 2 L E V E L 3L E V E L 1 S i m p l i f i e d M e t h o d sQ u a n t i f i e d R i s kS c o r i n g M e t h o d s

M i x ed A n a l y s i s M e t h o dsQ u a l i t a t i ve

N e x t C y c le E n g i n e e r N e x tE v a l u a t e A l t e r n a t i v e s I n s p e c t i o n , P i p e l i n e O p e r a t i o n s

M a i n t e n a n c e , L o a d i n g s M a i n t e n a n c e P r o t e c t i o n I n s p e c t i o n s R e p a i r C y c le

RAM PIPE REQUAL

RAM PIPE REQUAL Level 2 Method Base on physics - mechanics

Simplified models

RAM approach

Performance databases

Test data verified

Instrumented & un-instrumented

Linguistic & quantitative variables

Level 2 Burst Capacity Damaged / Defective

Intact: pB = SU (t / R)

Corrosion

pB = (SU / SCFC )(t / R)

SCFC = 1+2(tc / R)0.5

R

t

tc

Pf = P [ Demand (S) " Capacity (R) ]

.

R

p r o b a b i l l i t y

r e l a t i v e f r e q u e n c y de m and ( S ) o r

c apac it y ( R)

S

Rs t ro n g e r

p ro p o rt io n a l t o p ro b a b ilit y o f

f a ilu re ( Pf )

Pf

10 0

10 -1

10 -2

10 -3

10 -4

10 -5

10 -6

FS 50

s=0.1 s=0.2 s=0.3 s=0.4

2 4 6 8 10

Nominal Values & Biases

pB = pO (BpO / BpB ) exp ( b sb s ) = pO B exp ( b s )b s )

prob

abili

ty

ss B

B

Bias = actual / nominal

Bia

s =

Mea

sure

d B

urst

Pre

ssur

e /

Com

pute

d B

urst

Pre

ssur

e

0.4

0.8

1.2

1.6

2

.01 .1 1 5 10 2030 50 7080 9095 99 99.999.99 Percent

http:99.999.99

0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001

Failu

re R

ate

Gulf of Mexico Pipelines: Pf " 1 to 2 E-3 per year

0

oil gas

8080 8181 8282 8383 8484 8585 8686 8787 8888 8989 9090 9191 9292 9393 9494 9595 9696

Year

Corrosion is the Primary Problem OTHER

STRUCTURAL3% 6% UNKNOWNNAT.HAZARD

1%

CORROSION 47%ERROSION

MATERIAL 2%

26% ANCHORING 2%

4%

FIRE/EXPLOSION 0%

IMPACT 8%

CONSTRUCTION 1%

Corrosion Rates from Database

Time Dependent Reliability

Corrosion: Instrumented 1

0.8

0.6

Prob

abili

ty

0.4

0.2

Alyeska Pipeline UK Oil Pipelines

0.05 0.1 0.15 0.2 0

Corrosion Rate (mm / year)

0

Probabilities of Detection

Measurement Accuracy tC50 = tCD ( BDt ), V tC50 =25 % to 35 %

Bia

s =

1.4

1.35

1.3

1.25

1.2

1.15

1.1

1.05

1

Pig C Pig A

50 100 150 200 250 300

Pit Depth (mils)

20-inch gas line instrumented Pig C

0 5000 10000 15000 Distance (m)

0.05

0.1

0.15

0.2

0.25

0.3

0.35

Measured (% t) Corrected (% t)

Mea

sure

d C

orro

sion

(% t)

Probabilities of Failure: Detected & Not Detected

0.01

0.015

0.02

0.025

0.03

Prob

abili

ty o

f Fai

lure

0 5000 10000 15000 Distance (m)

AN

NU

AL

PRO

BA

BIL

ITY

OF

INSU

FFIC

IEN

T Q

UA

LITY

Fitness for Purpose1

0.1

0.01

0.001

0.0001 1 10 1 10 2 10 3

COST RATIO x PVF

Marginal

Optimum

Bay Campeche pipelines risers

Summary RAM PIPE REQUAL approach to

requalification of pipelines

Corrosion is the primary problem Need to develop industry database on

performance of marine pipelines

RAM PIPE REQUAL project continuing with industrial guidance

POP (Performance of Offshore Pipelines) Project

Pipelines proposed for abandonment

In-line instrumented and un-instrumented

Predictions of burst pressures & defects

Hydrotest pipelines to failure & recover

Perform material and geometry tests

Revise predictions Contact James Wiseman at: james@winmarconsulting.com

mailto:james@winmarconsulting.com

RAM PIPE REQUAL: A Risk Assessment & Management Based Process for the Requalification of Marine Pipelines Topics RAM PIPE REQUAL Project RAM. Risk Assessment Risk Management Accidents are caused by people. and so are successes Organizations have major influences. Primary factors. Three key strategies Level 2 Method Summary