C Course Notes (Fitness for Purpose)

7/24/2019 C Course Notes (Fitness for Purpose)

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Pipeline Defect Assessment

Phil Hopkins

Penspen Ltd., UK

([email protected])


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Contents

1. INTRODUCTION.....................................................................................................2

2. O! "#$% I" # TR#N"&I""ION PIP%LIN%'......................................................2.1 GENERAL...........................................................................................................4

. D%$%CT" IN # TR#N"&I""ION PIP%LIN% "*"T%& + T% N%%D $OR $ITN%""$ORPURPO"%......................................................................................................-3.1 DEFECTSINPIPELINES.......................................................................................5

. C#N I #PPL*, #ND DO I N%%D TO U"%, $ITN%""$ORPURPO"% &%TOD"'1

4.1 PHASE1 - APPRAISAL........................................................................................14.2 PHASE2 - ASSESSMENT.................................................................................... 14.3 PHASE3 - SAFETYFACTORSANDPROBABILISTICASPECTS.................................24.4 PHASE4 - CONSEQUENCE.................................................................................24.5 PHASE5 - REPORTING.......................................................................................2

-. #""%""IN D%$%CT" #ND D#% IN # TR#N"&I""ION PIP%LIN% "*"T%&................................................................................................................................ 25.1 INTRODUCTION...................................................................................................25.2 DECIDINGONTHECORRECTLEVEL OFASSESSMENT.........................................35.3 FITNESS-FOR-PURPOSEASSESSMENTMETHODSFORPIPEUNDERINTERNALPRESSURELOADING.................................................................................................45.4 CONSTRUCTINGDEFECTASSESSMENTPLOTS....................................................3

/. N%! "TRUCTUR#L R%LI#0ILIT* &%TOD" LI&IT "T#T% #N#L*"I"..........1 RELIABILITY-BASEDLIMITSTATEDESIGN.............................................................4

3. CONCLU"ION"....................................................................................................../

4. R%$%R%NC%".....................................................................................................15

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1. INTRODUCTION

These course notes explain how to conduct fitness-for-purpose assessments (sometimes calledEngineering Critical Assessments (ECA)) of defects in a transmission pipeline, and present a summary

of the methods aaila!le" The methods coer a wide range of defects, and can !e applied to !oth onshoreand offshore oil and gas pipelines" The following types of defect are discussed#

$ouges, %ents, %ents and $ouges

Corrosion

$irth &eld %efects

'tress Corrosion Cracing

aterial %efects

Construction %efects

1.1 o7 do Pipe8ines $9i8'*il and gas pipelines carry ha+ardous products, !ut it is important to remem!er that it is the product thatis ha+ardous, not the pipeline" The pipeline will hae high relia!ility if it is correctly designed,maintained and operated"

ipelines can fail due to#

natural disasters or acts of $od,

gross human error,

sa!otagewars

existing defects in a new pipeline or introduced during operation

Engineers can do little to preent i . iii", !ut hae many tools aaila!le to reduce i"

1.2 De98in: 7ith Risks

There are millions of ilometres of transmission pipelines around the world" The oil and gas transmissionsystem in &estern Europe alone is oer /01,111 m in length" A pipeline, and all its associated plant,must !e operated safely and efficiently" There are four ey issues (2riss2) in the operation of thesesystems#

/" Safety- the system must pose an accepta!ly low ris to the surrounding population,

3" Security of Supply - the system must delier its product in a continuous manner, to satisfy theowners of the product (the 2shippers2) and the shippers2 customers (the 2end users2), and hae lowris of supply failure,

4" Cost Effectiveness- the system must delier the product at an attractie maret price, and minimiseris of losing !usiness,

5" Regulations - the operation of the system must satisfy all legislation and regulations, and thisusually re6uires the operator to assess, and mitigate, pipeline-associated riss"

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An operator must ensure that all riss are accepta!ly low" 7or most of the lifetime of a pipeline, this willnot !e a pro!lem, !ut occasionally, an operator will detect, or !ecome aware, of defects in their pipeline"8n the past, this has usually led to expensie shut-downs and repairs" 9oweer, recent years hae seenthe increasing use of fitness-for-purpose methods to assess these defects" These course notes presentsome of the fitness-for-purpose methods applica!le to defects in transmission pipelines"

1.2 $itness ;o< P=/1 contains detailed engineeringcritical assessment methods, and can !e applied to defects in pipelines" Also, A8 0=>, which has similarmethods to


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2. HOW SAF IS A TRANS!ISSION PIP"IN#

2.1 eneG= and />>4"These casualty figures are ery low compared with other riss to the general pu!lic in the :'A (Ta!le3)"

T #0L% 2 Re89tie 0117alls F 311

Accidental oisoning 5 /11

7irearm Accidents =11

ipeline failures can also cause enironmental damage" 7igure / shows the total amount of oil spills intothe marine enironment !etween />>1 and />>>" early /,111 million gallons (4 million tonnes) werespilled in this period, !ut oer 01I was due to taner spills# pipelines accounted for only F"5I of totalspills" 'u!-sea pipelines can and do fail (see 7igure 3, later), !ut they tend to spill less product that a seataner" The taners at sea today are massie# the Exxon Jalde+ that spilled oil in />G> released //million gallons (30=,111 !arrels or 4G,G11 metric tonnes) of its 04 million gallon cargo" // million

gallons would fill /30 *lympic swimming pools"

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). CAN I APP"%, AND DO I ND TO US, FITNSS'FOR'

PURPOS !THODS#

Any engineer with a potential defect pro!lem should structure their assessment as follows#

.1 Ph9se 1 #pp


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%efects in longitudinal (i"e" factory produced) pipeline welds usually fail !y a ductile fracturemechanism, although defects in circumferential (field) welds can fail !y !rittle fracture and may re6uire!rittle fracture calculations>D" 9oweer, new guidelines, specifically for transmission pipelines areaaila!le (see 'ection 0"4">, later)"

*ther pipeline defect such as loss of wall thicness defects within dents, can !e highly constrained, andcan exhi!it low ductility failures" These defects are often assessed using fracture mechanics !asedmodels that incorporate the effect of the material toughness>D(see 'ection 0"4"5, later)"

-.2 Decidin: on the Co


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78$:E /" ,8,EH8E %E7ECT A''E'')ET#

T9E 78JE 'TA$E'

"T#% 2

QUANTITATIVE -e.g. ASME B31.G

CODE

"T#%

QUANTITATIVE -e.g. FRACTURE

MECHANICS CALC.

"T#% -

PROBABILISTIC USINGLIMIT STATE ANALYSIS), OR

RIS ANALYSIS

"T#% 1

QUALITATIVE -e.g. COMPANY OR CODE

WORKMANSHIP LEVELS

"T#% 9

EPERIMENTAL-MODEL/FULL

SCALE TESTING

"T#% D

QUANTITATIVE -NUMERICAL

ANALYSIS

DEFECT

SIE 6 TYPE

AS ABOVE7

BUT ADDITIONAL

DEFECT7 PIPE 6

MATERIAL DATA

AS ABOVE7 PLUS7

DISTRIBUTIONS

OF PIPE7 MATERIAL

6 DEFECT DATA

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PIPE DATA7

PIPE PRESSURE

AS ABOVE7 PLUS7

PIPE SAMPLE

OR MATERIAL

PROPERTIES

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RE8ECT

RE8ECT

RE8ECT

ACCEPT

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RE8ECT

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ACCEPT

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9......SIMPLESTAGES.......:9.....................

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RE8ECT

ACCEPT

RE8ECT

-. $itness$o


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&hen summarising fitness-for-purpose methods, it is !est to start off with an assessment of the failurestress of a defect-free pipe" This gies a !enchmar failure stress for any pipeline"

8t should !e noted that safety factors are not gien or recommended in the following 'ections - they will!e dependent on the type of defect, the relia!ility of the data used in the assessment and the assessmentmethod, and the conse6uences of the failure of the defect" 8t is the responsi!ility of the engineerconducting the assessment to derie an appropriate safety factor"


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D!""?

7or a more accurate assessment, the method gien in A'E J888/4D is#

P K

Kf u=

+

/

1 F 1 5" " for ; /"0 (3)

P K

Kf u=

+

3

3

/

/ for ; N /"0 (4)

where#

KR

R

o

i

= (5)

oM outside radius of pipe %3 (mm)

iM inside radius of pipe, o-t (mm)

ore complex and accurate methods are aaila!le/5D"

-..2 o=:es o< "imi89< &et98 Loss De;ects2

External interference, or damage during construction, can cause gouges or scratches on the pipessurface" These metal loss defects may !e accompanied !y local plastic deformation"

8f this deformation has caused a dent, then the gouge must !e assessed using sophisticated fracturemechanics methods (see 'ection 0"4"5)"

Eenif

the

gougeis not

associated with a dent, there may !e a wor hardened layer at the !ase of the gouge which may reducethe local ductility and it may contain cracing"

8t is good practice to remoe any surface hardening !y grinding, although special procedures arere6uired for dressing damage on a lie pipeline" 7ollowing dressing, the gouge can !e assessed using itsdressed dimensions"

3'ee 'ection 0"4"/1"3 for methods for assessing the fatigue life of these type of defects"

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.&.2.1 0ially-$rientated Gou+es

8n ductile line pipe, the failure stress of an axially-orientated gouge su!?ect to internal pressure loading isdescri!ed !yFD#

2/

R

0

%efect %imensions

//

/

=M

A

A

A

A

o

of

or

//

/

=M

t

d

t

d

f

(0)

M c

Rt= +

/ 1 3F

33

" (F)

where#

Pt

Rf f=

fM failure stress (a)

M !ulging factor (E6" F is an example . there are many other formulations)

M flow stress (a)

d M maximum or aerage depth of part wall defect (mm)

3c M defect axial length (mm)

A M area of metal loss in the axial plane through the wall thicness (mm3)

AoM original area (d3c)

M outside radius of pipe (mm)

E6uation F can also !e used to determine the failure of a through wall defect# this failure of a throughwall defect will !e a rupture as the through wall defect is already leaing (see 7igure 4)" The stress to

fail (rupture) a through wall defect is :

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/=M (Fa)

Assessments of part wall defects are more accurate if the area ratio (AA o) is used" :sing the maximumdefect depth will !e conseratie (using the aerage defect depth is e6uialent to using the area ratio)"7igure 0 gies a simple representation of E6uations 0 and Fa"

$ouges can !e assessed using the a!oe e6uations, proiding your pipeline has a toughness N31B (/>)"ote that a gouge needs to !e checed for possi!le fatigue crac growth in some pipelines (e"g" someli6uid lines)"

Allowance (e"g" adding 1"0mm to defect depth) for the hard layer or su!-surface cracing is adisa!le, ifthey are to !e left in the pipeline, !ut you should ensure there is no ris of enironmental cracing, andno residual denting, and no pro!lems from cyclic loading"

ote that the assessment of gouges in pipeline is often not allowed !y codes and regulations F5-FFD due toconcern oer the difficulty of detecting associated denting and cracing" $ouges in thesecodesregulations re6uire repair"

.&.2.2 Circuferentially-$rientated Gou+es

7or a circumferential gouge (orientated at an angle of >1o to the pipeline axis) in ductile linepipe, thefollowing plastic collapse failure criterion due to ;astner/0Dmay !e used to calculate the axial failurestress#

2/0

R

%efect %imensions

( )( )( ) ( )

sin/3

/

+

=z

= = c

R

d

t/

where#

+M axial failure stress (a)

M flow strength (a)

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d M maximum or aerage depth of part wall defect (mm)

c M half circumferential length of defect(mm)

t M pipe wall thicness (mm)

M outside radius of pipe (mm)

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-.. Dents (7ith no 9ssoci9ted de;ects)

.&.&.1 urst Stren+th of Plain #ents

A dent in a pipeline is a permanent plastic deformation of the circular cross section of the pipe" A plaindent (sometimes referred to as a smooth dent) is defined as damage which causes a smooth change incurature of the pipe wall without a reduction in pipe wall thicness, i"e" it contains no defects orimperfections, such as a girth or seam weld" A ined dent contains rapid changes in contour"

%ents in pipelines are assessed using data deried from full scale tests" Harge dents can !e tolerated /FD,although their !ehaiour under cyclic loads, or when they coincide with seam welds, remains apro!lem/FD"

The effect of a plain dent (i"e" one with no associated loss of wall thicness defect, and of smoothshape) is to introduce high localised stresses and cause yielding in the pipe material" The high stressesand strains caused !y the dent are accommodated !y the ductility of the pipe" 7ull scale test results haeconfirmed this !y showing that plain dents do not generally affect the !urst strength of the pipeline /F-33D"*n pressurisation the dent attempts to moe outward, allowing the pipe to regain its original circular

shape" roided that nothing restricts the moement or acts as a stress concentration (e"g" a gouge or ain), then the dent will not reduce the !urst strength of the pipe"

Empirical limits for plain dents under static internal pressure loading hae !een deried from extensiefull scale testing" 8t should !e noted that all of the dent depths in the full scale tests were measured at+ero pressure"


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p

M stress intensification factor

p M cyclic pressure, psi

The reader is directed towards the original references/>-3/D

if they wish to conduct an assessment" Thefatigue model is !ased on an '- cure, modified for the stress concentration due to the dent" A stressintensification factor has !een deried from 7E analysis to account for the stress concentration due tothe dent" 8t is a function of the diameter to wall thicness ratio (%t), the ratio of the dent depth tonominal diameter, and the aerage pressure"

9oweer, it should !e emphasised, that for the fatigue design of pipelines !ased on '- cures, it isnormal practice to tae an '- cure !ased on the mean minus two standard deiations (i"e"approximately >="=I one tail confidence limit) and to then apply an allowa!le damage ratio of 1"/(e6uialent to a factor of safety of ten on fatigue life34D)"

-.. P89in Dent Cont9inin: 9 De;ect

.&.4.1 urst Stren+th

%ents containing defects can record low failure pressures" This is !ecause a defect in the dent is affected!y the stress concentration and the large strains within the dent@ this causes ductile tearing of the defectthrough the remaining ligament" The structure comprising the dent and the defect is complex andunsta!le"

7ull scale tests and ring tests inestigating the !urst strength of com!ined dents and defects hae !eenundertaen/F-33D"


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=

//0 /" SMS

d

t(l!fin3)

d

t

d

t

d

t

d

t/

3 4 5

//3 1 34 /1 F 3/ = 41 5=

+

+

" " " " "

d

t

d

t

d

t

d

t3

3 4 5

//3 / 4> = 43 /4 / /5 1=

+

+

" " " " "

K/

/ >= "

K3

1 0== "

(;/and ;3are non-linear regression parameters)

fM hoop stress at failure (l!fin3)

M plastic collapse stress of infinitely long gouge (l!fin3)

A M fracture Area of Charpy (1"1G4 in3for a 34 Charpy specimen)

E M Ooungs odulus (41,111,111 l!fin3)

CM 34 Charpy toughness (ftl!f)

dM maximum or aerage depth of part wall defect (in)

%1M dent depth measured at +ero pressure (in) ('ee eference /=)

t M pipe wall thicness (in)

M outside radius of pipe (in)

This failure criterion for a dent containing a metal loss defect does not gie a lower !ound failure stress"8t is a mean predictie model" Additionally, the model is semi-empirical and therefore limited !y the!ounds of the original test data/F-33D"

The model is well nown to gie large scatter in its predictions F4D, and it is considered more of a researchtool than a practical model, hence, its use in the field is no recommended without expert help"

.&.4.2 Fati+ue 3ife

The fatigue life of a dent containing a gouge is difficult to predict" 7ull scale tests indicate that thefatigue life of a com!ined dent and gouge can !e of the order of !etween ten and one hundred times lessthan the fatigue life of an e6uialent plain dent" 8n some cases een shorter fatigue lies hae !eeno!sered during testing"

-..- Dents on !e8ds

.&..1 urst Stren+th

7ull scale tests hae shown that dented seam welds can exhi!it ery low !urst pressures/F,/=D@ theminimum !urst pressure in one test was 35 percent of the 'O'" The low !urst pressures occur due tocracing in the weld as a result of the large stress and strains associated with the denting process" The

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!urst strength of a dented weld is critically dependent on whether or not the weld cracs during thedenting process, and whether or not the weld contains any fa!rication defects" There are no methods forrelia!ly predicting the failure pressure of a dented weld" Therefore, dented welds are usually repaired iffound in an operational pipeline"

.&..2 Fati+ue 3ife

There hae !een a num!er of fatigue tests on pipe rings containing dented seam welds /F,/=D, and fatiguetests on essels containing dented seam welds and dented girth welds 31,3/D" These tests hae shown thatthe fatigue life of a dent containing a weld can !e considera!ly lower than the fatigue life of ane6uialent plain dent" There are no methods for relia!ly predicting the fatigue life of a dented weld"

eference F4 gies full adice on the fatigue !ehaiour and eference F0 gies more practical guidance,!ut the following is a list of ey facts a!out seam welds in dents#

- Tests on low fre6uency E& and %'A& welds in dents, and deep dents on girth welds haeshown low fatigue lies"

- *ld welds such as acetylene welds or seerely flawed arc welds may hae poor fatigue lies"

- 8f the longitudinal seam or girth weld is good 6uality, ductile and free from ma?or defects (e"g"the girth weld is to A8 //15), the fatigue life can !e good

- 'ome tests on (the !etter 6uality) high fre6uency E& welds in dents hae shown good fatiguelies"

- &or in the >1s for *' in the :'A also supported the iew that shallow roc dents on girthwelds in gas lines were not a ma?or pro!lem

- $enerally, dents on girth welds or E&, or %'A& welds hae fatigue lies of a!out 31I that ofa similar plain dent with no weld"

-../ Note o; the #ssessment o; o=:es 9nd Dents

8f a gouge or dent is detected in the field, an engineer needs to chec#- %ET' * $*:$E'P C9EC; 7* ':7ACE CAC;8$ - There may !e some crac-

lie indications (spalling) caused !y the damaging o!?ect" 8f the cracing is deep, it may !eindicatie of a gouge that has craced due to denting (the denting may not !e isi!le as it mayhae !een pushed out (35,30))" This is seere, and re6uires repair"

- $*:$E'P C9EC; 7* EJ8%ECE *7 %ET8$ - The impact may hae also dented thepipe" esidual denting around a gouge is seere . see a!oe"

7inally, an engineer should always thin carefully of the conse6uences of getting things wrong" 8f yourdamage is in a pipeline in a high conse6uence area, you should inspect the damage closely !eforeassessment, and include appropriate safety factors in your assessment"

6P!"#$!" G%&'$ R!( 2))4*1


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-..3 Co


25/41

8n eference 3F the a!oe limit on the defect length is expressed in terms of


26/41

The effectie area method is incorporated into software referred to as 'TE$" 7or simple handcalculations the geometric shape approximation is recommended (this is the ar!itrary assumption thatthe defect area is 1"G0dH)"

The 'TE$ method is !ased upon the effectie area and effectie length of the corrosion defect" Theshape of the corrosion defects is not important, all that is re6uired is a profile of the defect (i"e" a seriesof length and depth measurements along the length of the defect)" %etermining the corrosion defectprofile re6uires a large num!er of depth measurements to !e taen at regular interals along the length ofthe defect" The defect can !e a single defect or a composite defect formed through defect interaction" Theprocedure is !ased upon considering arious su!sections of the total defect profile, and predicting thecorresponding failure pressure" This process is repeated for all possi!le com!inations of the arioussu!sections" 8n most cases, although not all, 'TE$ predicts a minimum failure pressure that is lessthan the alue predicted using the exact area, total length method3=D"

The modified


27/41

modelled !y an idealised patch containing a num!er of idealised pits" The assessment methoddetermines whether the defect !ehaes as a single irregular patch, or whether local pits within thepatch dominate" otential interaction !etween the pits is also assessed" The failure pressure is taen asthe minimum failure pressure from the analysis of all of the depth increments"

The methods deeloped from this pro?ect, together with those from a %J pro?ect (see !elow), hae!een incorporated into a %J ecommended ractice, -7/1/41D"

.&..4 #7 8oint Industry Pro6ect

A Boint 8ndustry ro?ect undertaen !y %et orse Jeritas (%J) has also produced guidelines for theassessment of corrosion defects, !ut considering axial and !ending loads in addition to internalpressure4/D" 8n the course of the pro?ect, /3 full scale tests on axial and circumferential single defectssu!?ected to internal pressure, and axial and !ending loads were carried out, together with a largenum!er of three-dimensional, non-linear, elastic plastic finite element analyses"

The results of the %J pro?ect were guidance for assessing single corrosion defects under !oth internalpressure and com!ined loading" 8n addition, a pro!a!ilistic cali!ration exercise was undertaen toproduce partial safety factors to !e used with the assessment method" The intention of proiding partialsafety factors, rather than a single safety factor, was to gie a more consistent leel of safety oer a widerange of defect si+es and pipeline geometries"

The methods deeloped from this pro?ect, together with those from a a

Ar!itrary1"G0(dt)D

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31144=0"13F3=0"1/

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The main methods (A'E


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9i8=! #%!"?> ,!=&@ @>/> "& +&%! >;"5J & ;== $#,=! !# (;='!# @&'=0 ;== %!!%%!0 & ;# >! 5J %;/=!G. T>! "&+";= =&;0 #&!" 0!"!0 ;# >! +!;" =&;0 &%

O"/! >! "&+";= =&;0# ;"0 %!##;"/!# ;%! 0!"!0 >! @== ,! 0!$!"0!" &"

>! (;%;,= & =&;0# ;"0 %!##;"/!# ;"0 >! +&0!= '"/!%;"!#G7 >! $;%;=#;! ;/&%# ;%! '#!0 & ;/>!(! ; #'/!" #!$;%;&" ,!@!!" >! =&;0 ;"0 %!## ;"/!$%&,;,= 0#%,'&"7 & !!$ >! $%&,;,= & ;='%! ,!=&@ ;" ;//!$;,=! ;%?! (;='!.

PROBABILITY

LOAD LG

DISTRIBUTION

RESISTANCE RG

DISTRIBUTION

M!;" S;! M;%?"

artial 'afety

7actor, artial 'afety

7actor,

N&+";= S;!

M;%?"7

/

H M

M!;"L&;0

N&+";=L&;0

!.?.

E)JS

MYS

M!;"R!##1;"/!

N&+";=R!##1;"

/!

!.?.

SMYS

O(!%=;$ #;='%!

$%&,;,=

$i:=


36/41

. CONC"USIONS

/" 7itness-for-purpose methods are aaila!le for a wide ariety of defects in transmission pipelines"'ome of these methods hae !een aaila!le, and tried-and-tested, for many years, and their use

should !e encouraged"3" There are fie leels (or stages) of defect assessment, ranging from simple methods detailed in

current codes, to highly sophisticated ris analyses, and limit state methods" A ery high leel ofexpertise is re6uired on the higher leels"

4" The defect assessment will only !e as relia!le and as accurate as the method used, and the data thatis aaila!le"

5" Corrosion in pipelines can !e relia!ly assessed, !ut account should !e taen of the accuracy andrelia!ility of the inspection data, and any future corrosion growth"

0" External interference can result in seere defects such as com!ined dents and gouges" These type ofdefects must !e assessed with caution, as their !ehaiour with time (i"e" fatigue) is not well-understood, and dents associated with welds are ery difficult to assess"

F" %efect assessment in pipelines is moing into relia!ility-!ased limit state design and ris analysis"These methods will allow een more sophisticated assessment, proiding accurate data is aaila!le"

3. RCO!!NDATIONS

This paper will end !y giing engineers general adice on assessing defects in pipelines (F=)#

/" AH&AO' T98; 'A7ETO . ipeline codes are safety standards, and an engineersprime role in any industry is to ensure safety" 'tructural assessments are safetyassessments"

3" 8EH8E %E'8$ C*%E' AE %AO / C*%E' . ipeline design codes gie usminimum structural integrity re6uirements . they are the starting point for integrity, notthe end point" A pipeline designed and !uilt to code will !e ery safe on its first day inserice" 9oweer, after day / the pipelines management dictates its safety, not thedesign code" Therefore, good managers and good management systems5are the ey topipeline structural integrity" This means a continual appraisal of technical issues such assmart pigging, ris management programmes, correct routeing etc", to achiee highintegrity"


37/41

will learn from their experience, and act accordingly, so it does not happen to you" Theywill then copy your practices, !ut you will then moe one step ahead againP and thentheir pipeline will again fail !efore yoursU

0" %* *T A:T*AT8CAHHO 'EHECT T9E H*&E'T


38/41

1(. RFRNCS

/" Anon", 28nterstate natural gas pipelines - %eliering energy safely2, 8nterstate atural $asAssociation of America eport, :'A, />>5"

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5" 9opins, ", 9aswell, B", The ractical Assessment ethods for Application to :; $asTransmission ipelines, The 8nstitute of aterials 3nd $riffith Conference, 'heffield, :;,'eptem!er />>0"

0" 9opins, ", Ensuring the 'afe *peration of *lder ipelines, 8nt" ipeline and *ffshoreContractors Association, 3GthConention, Acapulco, exico, 'ept" />>5"

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5F/-5G/, />=4"=" 'hannon, " &" E", />=5, 2The 7ailure 0, />GG"

>" Anon", 2$uidance on ethods for the %eriation of %efect Acceptance Heels in 7usion &elds2, >>" 7ormerly# Anon", 2$uidance on ethods for the%eriation of %efect Acceptance Heels in 7usion &elds2, >/

/1" 9opins, ", 9opins, 9", Corder, 8", The %esign and Hocation of $as Transmission ipelines:sing is Analysis Techni6ues, is and elia!ility Conference A!erdeen, :;, ay />>F"

//" 9opins, ", ew %esign ethods for Vuantifying and educing the um!er of Heas in *ffshoreand *nshore Transmission ipelines, European ipeline Heaage reention Conference, 8ChemE,Hondon, ay />>="

/3" 9opins, ", 9aswell, B", The ractical Application of 'tructural elia!ility Theory and Himit 'tateConcepts to ew and 8n-serice Transmission ipelines, 8nt" 'eminar on 8ndustrial Applications of'tructural elia!ility Theory, E'e%A, aris, 7rance, *cto!er />>="

/4" Anon", A'E


39/41

/=" 9opins, ", Corder, 8", Cor!in, "@ The esistance of $as Transmission ipelines to echanical%amage, aper J888-4, 8nternational Conference on ipeline elia!ility, Calgary, Canada, Bune/>>3"

/G" Bones, %"$"@ The 'ignificance of echanical %amage in ipelines, 4 8nternational, 3/, Bahrgang,9eft, =, Buly />G3"

/>" 7owler, B""@ Criteria for %ent Accepta!ility in *ffshore ipelines, *TC =4//, 30 th *ffshoreTechnology Conference, 9ouston, Texas, 4rd-Fth, pp 5G/-5>4, ay />>4"

31" 7owler, B"" Alexander, C"", ;oach, "B", Connelly, H""@ 7atigue Hife of ipelines with %entsand $ouges 'u!?ected to Cyclic 8nternal ressure, %-Jol" F>, ipeline Engineering, A'E />>0"

3/" 7owler, B"" Alexander, C"", ;oach, "B", Connelly, H""@ Cyclic ressure 7atigue Hife ofipelines with lain %ents, %ents with $ouges, and %ents with &elds, A$A ipeline esearchCommittee, eport -31/->3= and -31/->435, Bune />>5"

33" &ang, ;"C", 'mith, E"%", The Effect of echanical %amage on 7racture 8nitiation in Hinepipeart 8 - %ents, CAET, Canada, eport EH G3-// (T), Banuary />G3"

34" Anon", ules for 'u!marine ipeline 'ystems, %et orse Jeritas (%J) , %ecem!er />>F"

35" 9opins, ", 2The Application of 7itness for urpose ethods to %efects %etected in *ffshoreTransmission ipelines2, Conference" on 2&elding and &eld erformance in the rocess 8ndustry2,Hondon", />>3"

30" ;iefner, B"7", %uffy, A""@ Criteria for %etermining the emaining 'trength of Corroded Areas of$as Transmission ipelines, A$A *perating 'ection on Transmission, Conference, A$A />=4"

3F" Anon", 2anual for determining the emaining 'trength of Corroded ipelines2, A'8A'E G5, />G5"

3=" ;iefner,B"7", Jieth,"9"@ A odified Criterion for Ealuating the 'trength of Corroded ipe, 7inaleport for ro?ect 4-G10 to the ipeline 'uperisory Committee of the American $asAssociation, G>"

3G" osenfield,"B", ;iefner,B"7"@ roposed 7itness-for-urpose Appendix to the A'E


40/41

40" c%onald, ;", 9opins, ", The significance of em!edded non-planar defects in transmissionpipeline girth welds# a literature reiew, ipes and ipelines 8nternational, arch-April (art /),ay-Bune (art 3), />>0"

4F" ;nauf, $", 9opins, ", The E$ $uidelines on the Assessment of %efects in Transmissionipeline $irth &elds, 4 8nternational, 40, Bahrgang, 9eft /1-///>>F, pF31-F35"

4=" 9opins,", istone,J", and Clyne,A"B"@ A 'tudy *f The >4"

4>" %elanty, 5, />>5 (reported in Rimmermann, T", et al Target elia!ility Heels for ipeline Himit'tate %esign, 8nternational ipeline Conference - Jol" /, A'E, p"///)"

5=" Anon", ules for 'u!marine ipeline 'ystems, %et orse Jeritas, %J/>>F, orway (eportedin Biao, $", et al, The 'uper! ro?ect# &all Thicness %esign $uideline for ressure Containmentof *ffshore ipelines, *ffshore echanics and Arctic Engineering Conference, *AE />>F,7lorence, 8taly"

5G" Anon", ipelines for $as Transmission, European Committee on 'tandardisation, peE /0>5,/>>5 (%raft)"

5>" Anon", ipeline Transportation 'ystems for the etroleum and atural $as 8ndustries,8nternational *rganisation for 'tandardisation, 8'* C% /4F34, arch />>0, (%raft)"

01" Anon", Eisen Joor 'talen Transportleidingsystemen, etherlands Code E 4F01, 8,

'eptem!er />>3"

0/" c;innon, C", et al, A Case 'tudy of the F"

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6P!"#$!" G%&'$ R!( 2))4*1


41/41

04" & A axey, B 7 ;iefner, B Ei!er, A %uffy, %uctile 7racture 8nitiation, ropagation and Arrestin Cylindrical Jessels, A'T 'T 0/5, American 'ociety for Testing and aterials, hiladelphia,/>=3, pp" =1-G/"

05" ipeline esearch Committee of the American $as Association" roceedings of the 'ymposia onHine ipe esearch, :'A, />F0 onwards" www"prci"com"

00" 'eptem!er />>4"

0=" " 9opins, A Cosham, 9ow To Assess %efects 8n Oour ipelines :sing 7itness-7or-urposeethods Conference on Adances in ipeline Technology >=, %u!ai, 8 to *cto!er 5, 3113"

F3" A" Cosham, " 9opins, The Assessment *f Corrosion 8n ipelines . $uidance 8n The ipeline%efect Assessment anual (%A), 8nternational Collo6uium elia!ility of 9igh ressure 'teelipelines, 3=-3Gth arch 3114 . rague, C+ech epu!lic"

F4" A" Cosham, " 9opins, The Effect *f %ents 8n ipelines . $uidance 8n The ipeline %efectAssessment anual, roceedings 8CJT-/1, Buly =-/1, 3114, Jienna, Austria"

F5" Anon", anaging 'ystem 8ntegrity for 9a+ardous Hi6uid Hines, /st Ed", A'8A'E 'tandard//F1-311/, oem!er 311/"

F0" Anon", anaging 'ystem 8ntegrity of $as ipelines, A'E "
http://www.prci.com/http://www.prci.com/

Documents

C Course Notes (Fitness for Purpose)