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매설배관 건전성평가 매설배관 건전성평가 Pipeline Integrity Assessment 코렐테크놀로지㈜ 이선엽

Pipeline Integrity Assessment

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Pipeline Integrity Assessment

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  • Pipeline Integrity Assessment

  • ?

    ?

    GNP 4% GNP 4%

    (1999) 1/3

    (1999) 1/3

  • Summary of Incident CausesSummary of Incident Causes

    ASME Causes of Gas Transmission Incidents

    External Corrosion

    Third Party Damage

    I t O ti

    Misc

    Natural Forces

    Internal Corrosion

    Constr/Instal

    Other Failures

    Unknown

    Incorrect Operation

    Non-PipePipe

    Malfunction

    Prev. Damgd Pipe

    Mfr

    Constr/Instal Pipe

    0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0

    Vandalism

    Stress Corrosion Cracking

    Avg Annl Incidents, 85-01

  • COST OF CORROSIONCOST OF CORROSION

    $5 0 bil$5.0 bil.

    4Department of Transportation (DOT), USA, 2001 ($276 bil.)

  • Cost Estimate Example Offshore PNG PipelineCost Estimate Example Offshore PNG Pipeline

    C (US $ Milli )Category

    Cost (US $ Million)

    7.4 MPa 8.4 MPa 10 MPa 12 MPa

    Bare Pipe Materials 374.1 314.4 296.5 228.8

    External Coating 44.1 44.1 44.1 42.0

    Internal Coating 21.2 21.3 21.2 21.2

    Weight Coating 67 2 63 7 57 8 54 0Weight Coating 67.2 63.7 57.8 54.0

    Cathodic Protection 20.7 20.5 20.5 20.2

    Pipe Laying 80.7 78.1 80.8 80.8

    Dredging& Backfill 17.7 17.1 16.8 16.1

    Mobil. & Demobil. 8.4 8.4 8.4 8.4

    Total 634 1 567 6 546 1 471 5Total 634.1 567.6 546.1 471.5

    10 15% of total direct construction cost for corrosion protection (coating + CP)(Cited from Feasibility Study Report for Irkutsk PNG pipeline)

  • CASE HISTORIES ON UNDERGROUND CORROSIONCASE HISTORIES ON UNDERGROUND CORROSION

    Corrosion on the pipeline

    Corrosion on the bottom plates of aboveground storage tank

  • CORROSION IN ANAEROBIC SOILCORROSION IN ANAEROBIC SOIL

  • Chemical/microbiological corrosion

    /

    Electrical corrosion

    10

  • (corrosivity)

    , ,

  • 333

    vs. vs. P/S Disbonded area Sulfate

    2

    P

    0

    2

    P

    0

    2

    P

    0

    0 1 2 3 40

    1

    0 20 40 60 80 100 1200

    1

    2 0 1 8 1 6 1 4 1 2 1 00

    1

    3

    2

    100 101 102 103 104

    [SO42-] (mg/g of soil)

    0 20 40 60 80 100 120

    Disbonded Area (cm2)

    -2.0 -1.8 -1.6 -1.4 -1.2 -1.0

    P/S (V/CSE)

    pH SRB

    2

    Resistivity

    2

    P

    0

    1

    P

    0

    1

    P

    0

    0

    1

    4 5 6 7 8 9 100

    0

    1

    103 104 105 106 107 108 109

    SRB (cells/g of soil)

    4 5 6 7 8 9 10

    pH101 102 103 104

    0

    Resistivity (Ohm.cm)

  • Soil Resistivity Soil Resistivity Wenner 4-Pin Resistivity Measurement

    I

    E

    SSS

    . = RA/L (cm) ()

  • 4-pin method

    Soil box

  • SOIL RESISTIVITY SURVEY: EQUIPMENTSSOIL RESISTIVITY SURVEY: EQUIPMENTS

  • Soil pin

    . .

    a/2 .

  • 5 000 ohm cm 5,000 ohm.cm

  • () ()1.E+06

    1 E+051.E+05

    t

    y

    (

    .

    c

    m

    )

    1.E+04

    S

    o

    i

    l

    R

    e

    s

    i

    s

    t

    i

    v

    i

    t

    1.E+03

    S

    corrosive

    1.E+020 10 20 30 40 50 60 70 80 90 100 110 120 130

    Distance (km)

  • AA

    A B ?

    B

    19

    A, B ?

  • SOIL RESISTIVITY SURVEY: DEPENDENCY ON SOIL DEPTH: DEPENDENCY ON SOIL DEPTH

    A. . B. . . C. .D.

    20

  • SOIL RESISTIVITY SURVEY: BARNES METHOD: BARNES METHOD

    T

    1h1

    2

    3

    h2

    h3 3

    4

    h3

    h4

    h

    S

    1111S

    5h5

    21n21 RRRR

    S

  • SOIL RESISTIVITY SURVEY: BARNES METHOD: BARNES METHOD

    4m 111 42

    4224

    RRR

    RRR

    1. 2m, 4m

    4242

    4242

    RRRR400

    RRR

    1. 2m, 4m (R2, R4)

    2. R2-4 42

    42 RR

    3. 2-4

    22

  • SOIL RESISTIVITY SURVEY: BARNES METHOD: BARNES METHOD

    Pin 2m R2 = 6.3 Pin 4m R4 = 1.3

    2m 2= 22006.3=7,917 cm 2m 4= 22006.3=3,267 cm

    2-4 = 400(R2R4)/(R2-R4)00 ( 3 6 3)/(6 3 3) = 400(1.36.3)/(6.3-1.3)

    = 2,061

    Test data Barnes AnalysisTest data Barnes Analysisa (cm) R (Ohms) Avg. 1/R (1/R) Layer R Layer

    200 6.3 7,917 0.16 - 6.3 7,917

    23

    400 1.3 3,267 0.77 0.61 1.64 2,061

  • SOIL RESISTIVITY SURVEY: BARNES METHOD: BARNES METHOD

    Test data Barnes AnalysisTest data Barnes Analysisa (cm) R (Ohms) 1/R (1/R) Layer R Layer

    150 1.1 0.91 - 1.1 1,040300 0.89 1.1 0.19 5.3 4,995450 0.46 2.2 1.1 0.91 858600 0 14 7 1 4 9 0 20 190600 0.14 7.1 4.9 0.20 190750 0.083 12 4.9 0.20 190900 0.076 13 1.0 1.0 94

    Ref.) T.H. Lewis, Jr., Deep Anode Systems, NACE (2000) p.7-11

    24

  • (sulfate- (sulfatereducing bacteria; SRB)

  • CORROSION IN ANAEROBIC SOILCORROSION IN ANAEROBIC SOIL

  • SULFATE-REDUCING BACTERIA (SRB)

    SO 2 ATP APS PPi

    SULFATE-REDUCING BACTERIA (SRB)

    SO42- SO42- + ATP APS + PPi Pi

    2e-

    SO32- + AMP

    Enters cell

    H+

    S2O52- Metabisulfite

    2e-

    2e- S2-

    S2O42- Dithionite

    S3O62- Trithionate 2e- S2O32-

    Outside cell

    2e 2e Thiosulfate

    Anaerobic bacteriaNeutral environments

    Reducing sulfate to corrosive sulfides

    27

  • SRB Population vs. Soil Key Parameters

    107

    108

    109

    p y

    Resistivity Redox potential

    7

    108

    109

    107

    108

    109

    104

    105

    106

    10

    c

    e

    l

    l

    s

    /

    g

    -

    s

    o

    i

    l

    )

    105

    106

    107

    e

    l

    l

    s

    /

    g

    o

    f

    s

    o

    i

    l

    )

    104

    105

    106

    10

    c

    e

    l

    l

    s

    /

    g

    -

    s

    o

    i

    l

    )

    101

    102

    103

    S

    R

    B

    (

    c

    Clay content102

    103

    104

    S

    R

    B

    (

    c

    e

    101

    102

    103

    S

    R

    B

    (

    c

    108

    109

    -0.2 0.0 0.2 0.4 0.6 0.8100

    Eh (V/NHE)

    Clay content102 103 104 105 106

    101

    ( cm)0 10 20 30 40 50 60

    100

    Clay Content (%)

    108

    109

    106

    107

    108

    /

    g

    -

    s

    o

    i

    l

    )

    105

    106

    107

    /

    g

    -

    s

    o

    i

    l

    )

    Anaerobic,Neutral,High clayey,L i ti it

    103

    104

    105

    A

    P

    B

    (

    c

    e

    l

    l

    s

    /

    102

    103

    104

    S

    R

    B

    (

    c

    e

    l

    l

    s

    / Low resistivity,High water content

    102

    10

    102 103 104 105 106 107 108 109

    SRB (cells/g-soil)

    0 10 20 30 40 50100

    101

    Water Content (%)

    Water content APB

  • C i E Ti

    Corrosion vs. Exposure Time

    04A

    -0.6

    -0.4 SRB-active Biocide added APB-active

    V

    /

    S

    C

    E

    )

    2

    U

    n

    i

    t

    )

    25m A

    C

    10

    -0.8E

    c

    o

    r

    r

    (

    m

    V

    0 2 4 6 8 100

    1

    AlSiFe

    O

    C

    P

    SFe

    Fe

    C

    o

    u

    n

    t

    s

    (

    A

    r

    b

    .

    U

    20m

    0.3

    0.4-1.0

    0.36mm/y

    t

    e

    (

    m

    m

    /

    y

    )

    B D

    Energy (keV)

    0.1

    0.2

    o

    r

    r

    o

    s

    i

    o

    n

    R

    a

    t

    20m

    2m

    2.0

    0 50 100 150 2000.0C

    o

    Time (Day)1.0

    1.5

    2.0

    O SFe

    n

    t

    s

    (

    A

    r

    b

    .

    U

    n

    i

    t

    )

    0.5

    1.0

    1.5

    Fe

    O

    C P

    S

    Fe

    C

    o

    u

    n

    t

    s

    (

    A

    r

    b

    .

    U

    n

    i

    t

    )

    0 2 4 6 8 100.0

    0.5

    Al

    SiFe

    CP

    Fe

    C

    o

    u

    n

    Energy (keV)

    0 2 4 6 8 100.0

    Si Fe

    Energy (keV)

  • MIC in Aerobic Condition2.0

    MIC in Aerobic Condition

    1.0

    1.5

    O SFe

    A

    r

    b

    .

    U

    n

    i

    t

    )

    0 0

    0.5

    Al

    SiFe

    CP

    Fe

    C

    o

    u

    n

    t

    s

    (

    A

    0 2 4 6 8 100.0

    Energy (keV)

    SRB

  • CPCP CPCP SRB-active soil

    Ref.) K. Kasahara, et al., Corrosion, 55(1) (1999) 74

    The change of local chemistry at metal

    OH2He2OH2 22

    The change of local chemistry at metal surface, inducing an increase of pH.

    Effective tool for prevention of SRB-induced MIC in soil.

    31

  • CP vs MICCP vs. MIC3

    2

    P

    0

    1

    -2.0 -1.8 -1.6 -1.4 -1.2 -1.00

    P/S (V/CSE)P/S (V/CSE)

    Despite of coating and CP, MIC occurred. All corrosion occurred the region under the disbonded coating. All corrosion occurred the region under the disbonded coating.

  • Pt & Reference

    ~15cm depth

    PtRef2PipeRef1

    15cm depth

    1. Ref 1 vs. Pipe 2. Ref 2 vs. Pipe 3. Ref 2 vs. Pt

    33

  • Potential mV vs. Cu/CuSO4

    P/S -1430 (-1200)

    I C i 610 ( 500)In Crevice -610 (-500)

    Pt Electrode -480Pt Electrode 480

    Redox -160 (vs. NHE)*1

    *1. At pH 7

    34

  • ANSI/AWWA ANSI/AWWA < 700700 - 10001000 - 12001200 - 15001500 2000

    108521

    (polyethylene encasement) 1500 - 2000

    > 200010

    pH0 - 22 - 4

    53

    encasement)

    10

    4 - 6.56.5 - 7.57.5 - 8.5> 8.5

    00**03

    (mV)> 10050 - 1000 - 50< 0

    03.545

    (sulfide)i i 3

    DIN 50929 ,

    positivetracenegative

    3.520

    (moisture)(drainage) ,

    21

    35

    , ,

    10

  • CORROSIVITY MAP ( )CORROSIVITY MAP ( )

    36

  • Corrosion of Steel in Soil EnvironmentCorrosion of Steel in Soil Environment

    P=ktn

    e

    p

    t

    h

    /

    m

    m

    )

    x

    i

    m

    u

    m

    P

    i

    t

    D

    e P=ktn Power law P: t:

    P

    (

    M

    a

    x

    k, n:

    t, (Time/year)

    k n k n . .

    37

  • )(LogpH014.0ClayE050.0)Cl(Log203.0S/P749.0)SRB(Log069.0700.0LogP hc

    2.5

    R=0.942R=0.942

    )(gpy)(g)(gg hc

    1 5

    2.0 372.0c0 tP500.0P

    1.0

    1.5

    P

    0

    ,

    o

    b

    s

    0.5

    Chemical factors Biochemical (microbial) factors CP effects

    0.0 0.5 1.0 1.5 2.0 2.50.0

    38

    P0, cal

  • INTERFERENCEINTERFERENCE

  • (interference)

    (stray current; ) () (: )

    (; stray current corrosion)

    ,

  • , , AC

  • (anodic interference) (anodic interference)

    , ,

  • (anodic interference) (anodic interference)

  • (cathodic interference) (cathodic interference)

    + crossing

  • 3

    1

    2 Rectifierpower up

    V

    /

    C

    S

    E

    -1

    0

    Rectifier

    i

    n

    e

    P

    o

    t

    e

    n

    t

    i

    a

    l

    ,

    corrosion !!

    -2

    P

    i

    p

    e

    l

    0 50 100 150-3

    Distance, m

  • STS 304L : 1 : 1.2V/CSE

    DC

  • (combined interference) (combined interference)

  • (combined interference) (combined interference)

  • 49

  • 9 1 9 1

    25km, 9 7 2

    10km, 3 3k : ~3km

    80

    90

    100

    8

    9

    10

    )

    feeding current ()

    40

    50

    60

    70

    80

    4

    5

    6

    7

    8

    e

    C

    u

    r

    r

    e

    n

    t

    ,

    I

    l

    '

    '

    '

    (

    A

    )

    Il '''/I (%

    0

    10

    20

    30

    40

    0

    1

    2

    3

    4

    T

    o

    t

    a

    l

    L

    e

    a

    k

    a

    g

    %)

    7000A leak current0 2 4 6 8 10

    Substation Spacing, L (km)

    leak current

  • vs vs.

  • . (, , )

    /

    / / (BS EN 50162: 2004) ,

    (KS C IEC 62128-2)( )

    ( /)

  • -

    : , (2005) p.83

  • 1010 9

    8

    10

    9

    8 8

    7

    8

    7

    6

    6

    5

    5

    4

    4

    3 4

    3

    3

    2

  • 191817161514

    1313

    12

    11

    10

    9

    8

    76

    5

    4

    3

    22

    1

  • / /

    I-beam

    I-BEAM ()

    () I beam I-beam / /

  • / ()/ ()

    1 2

    [V][A]

    [A] [A] [A] [A]

    15.5 19.0 7.2 4.7 0.04 3.2 79% 15.5 18.9 - 9.9 4.2 4.7 100%

    1 15.5 18.5 - - 0.9 12.9 75%

    2 15.5 16.8 - - - 8.0 48%

    15.5 14.6 - - - - 0%

    // - : 19A 14.6A (23% ) 0 82 1 06 (30% )- : 0.82 1.06 (30% )

  • - 40

    30

    m

    m

    /

    y

    20

    o

    n

    R

    a

    t

    e

    ,

    m

    10

    m

    C

    o

    r

    r

    o

    s

    i

    o

    0

    M

    a

    x

    i

    m

    u

    m

    -800 -600 -400 -200 0 200

    Potential mV/CSEPotential, mV/CSE

  • Rail spike

  • : 2-3 1.2m

    61

  • - () ( ) (-)

  • Forced Drainage Bond Using a Potential Controlled Rectifier ( )( )

    PotentialControlled

    Is

    ControlledRectifier

    Is

    structure buried referenceelectrode

  • () ()

  • () ()-0.5

    Case Histories on Mitigation

    -2.0

    -1.5

    -1.0

    C

    S

    E

    )

    instant off 7.5A 12.5A

    Case Histories on MitigationClients: KOGAS, KOWACO

    -3.5

    -3.0

    -2.5

    E

    (

    V

    V

    s

    .

    C

    32 30 28 26 24 22 20 18-4.0

    T/B No.

  • T3-14

    R3-5

    ()R ()R

    R3-4T3-15

    C3-8 ()T

    C ()

    R3-3

    T3-11

    T3-12

    C3-4

    R4-4

    R3-2

    T3-10R4-2

    R4-3R4-5

    R4-6

    R4-7

    R3-1 C3-2

    R4-1R4-8

    T3-8

    C3-7

    T3-6T3-7

    T3-4

    T3-5

    T3 2T4-9 T3-3

    66

    C3-6T3-2

    C3-9

  • Corrosion Control of Underground PipelinesCorrosion Control of Underground Pipelines

    Base metal: CS Coating + Cathodic Protection (CP)

    ()

    , CP

  • Corrosion Protection Corrosion ProtectionTB

    coating & lining () CP anodic protection corrosion inhibitor material selection Mg

    : Mg, Al

    +g : , +

    -

  • Cathodic Cathodic Protection (CP)Protection (CP)Cathodic Cathodic Protection (CP)Protection (CP)

    CPCP is achieved by supplyingis achieved by supplying ee-- to the metalto the metal CP CP is achieved by supplying is achieved by supplying ee to the metal to the metal structure structure to to be protected and widely used be protected and widely used in:in:

    1) 1) long pipelineslong pipelines,,2) gas and oil transmission lines,2) gas and oil transmission lines,3) ships,3) ships,4) chemical processing 4) chemical processing equipments, etc.equipments, etc.

    Eapp

    Fe Cu Fe Cu

    E E E

    (a) before protection

    EFeECu-EFe

    (b) after protection

  • Galvanic (Sacrificial) Anode CP SystemGalvanic (Sacrificial) Anode CP SystemGalvanic (Sacrificial) Anode CP SystemGalvanic (Sacrificial) Anode CP System

    CURRENTCURRENT

    ANODEANODE

  • Impressed Current CP (ICCP) SystemImpressed Current CP (ICCP) SystemImpressed Current CP (ICCP) SystemImpressed Current CP (ICCP) SystemPowerSourceSource

    +-

    T T

    CUR

    CUR

    C

    U

    R

    R

    E

    N

    T

    C

    U

    R

    R

    E

    N

    T

    RRENT

    RRENT

    ANODEANODE

  • Relative Economic Range for Galvanic and Impressed Current Systems F i f C R i d d S il R i i ias a Function of Current Required and Soil Resistivity

    3 5

    3.0

    3.5

    2 0

    2.5Impressed Current

    1.5

    2.0

    0.5

    1.0Galvanic

    10 20 30 40 50 60 70 80 90 1000

    Soil Resistivity ( in ohm-m)

  • CP CP

    73

  • CP CP

    74

  • Effect of CPEffect of CP

  • NACE RP0169 Control of External Corrosion on

    Underground or Submerged Metallic Piping Systems (potential criteria) -850mV

    100mV 100mV

    76

  • : -850mV vs Cu/CuSO4 : -850mV vs Cu/CuSO4 : -5,000mV P/S

    Pipe to Soil () Pipe to Soil () : Sat. Cu/CuSO4

    Ag/AgCl T/B T/B

    300m - 500m

  • Equivalent Circuit for Corrosion Cell

    ElectrochemicalReaction

    ElectrochemicalReaction

    Rct

    R

    RctResistance of Solution

    Rsol

    Anode CathodeDouble-layerCapacitance

    Double-layerCapacitance

    : Rsol

    78

  • Voltage and Current Lines Around a Bare Pipeline R i i C th di P t ti C tReceiving Cathodic Protection Current

  • V

    )

    ( )

    ON Potential

    V

    )

    ( )

    ON Potential

    a

    l

    (

    -

    m

    V

    ON Potential

    OFF Potential

    IRIRON-IR -850 mVCSEOFF -850 mVCSEa l

    (

    -

    m

    V

    ON Potential

    OFF Potential

    IRIRON-IR -850 mVCSEOFF -850 mVCSE

    P

    o

    t

    e

    n

    t

    i

    a

    100 mV Polarization

    OFF 850 mVCSE

    P

    o

    t

    e

    n

    t

    i

    a

    100 mV Polarization

    OFF 850 mVCSE

    P

    Native (Free Corroding Static) Potential

    100 mV DepolarizationP

    Native (Free Corroding Static) Potential

    100 mV Depolarization

    (+) Native (Free Corroding, Static) Potential(+) Native (Free Corroding, Static) Potential

    80

  • 81

  • P/S ( )P/S ( )

    A

    B

    82

  • Reference Electrode Placed Close to Pipe Surface to Mi i i IR D E i P t ti l M t Minimize IR Drop Error in Potential Measurement

  • IR free Potential (Instant Off Method)IR-free Potential (Instant-Off Method)

    V

    )

    ( )

    ON Potential

    V

    )

    ( )

    ON Potential

    a

    l

    (

    -

    m

    V

    ON Potential

    OFF Potential

    IRIRON-IR -850 mVCSEOFF -850 mVCSEa l

    (

    -

    m

    V

    ON Potential

    OFF Potential

    IRIRON-IR -850 mVCSEOFF -850 mVCSE

    P

    o

    t

    e

    n

    t

    i

    a

    100 mV Polarization

    OFF 850 mVCSE

    P

    o

    t

    e

    n

    t

    i

    a

    100 mV Polarization

    OFF 850 mVCSE

    P

    Native (Free Corroding Static) Potential

    100 mV DepolarizationP

    Native (Free Corroding Static) Potential

    100 mV Depolarization

    Time

    (+) Native (Free Corroding, Static) Potential(+) Native (Free Corroding, Static) Potential

  • Electrode for IR free Potential MeasurementElectrode for IR-free Potential Measurement

  • (polarization shift) (polarization shift) 100mV 100mV 100mV (, )

    86

  • (polarization shift) (polarization shift)

    87

  • Test Point Test Point - -500

    -700

    -600

    -900

    -800CP criteria

    TB 315.4mA( m

    V

    C

    S

    E

    )

    -1100

    -1000

    TB 126.8mA

    TB 414.7mA

    TB 511.4mA

    TB 6 TB 7

    TB 80 mA

    TB 925.2mA

    p

    o

    t

    e

    n

    t

    i

    a

    l

    -1300

    -1200TB 255mA

    19.2mA 34.3mA

    P

    /

    S

    0 1 2 3 4 5 6 7 8 9 10-1500

    -1400

    Distance (km) !!!Test points TPTP

  • Test Point Test Point - AbovegroundStorage Tank

    Test / AccessStation

    Storage Tank

    Grade

    f ll

    Rim 25' Center 55' Rim

    Reference CellMonitoring Tube

    On -1411 -698 -404 -601 -1455Off -902 -664 -402 -578 -911

    Potentials (mV)

  • Close Interval Potential Survey (CIPS)Close Interval Potential Survey (CIPS)

    s

    120od

    Ls

  • Pin pointing of Coating DefectsPin-pointing of Coating Defects

    DCVG (pulsed-direct current voltage gradient) method 3-4m

    5

    10

    15

    20

    -15

    -10

    -5

    0

    5

    Defect

    P

    o

    t

    e

    n

    t

    i

    a

    l

    D

    i

    f

    f

    e

    r

    e

    n

    c

    e

    (

    m

    V

    )

    0 1 2 3 4 5 6 7 8 9

    -25

    -20

    Measure Point

  • Pipeline operators concern and solutionPipeline operator s concern and solution

    Concern Solution

    Is protective coating sound? DCVG *1

    Is cathodic protection system working properly? CIPS*2p y g p p y

    What extent and where is the corrosion damage (metal loss?)

    ILI*3

    Is pipelines having corrosion defects safe? What will be the life?

    FFS*4

    What will the appropriate remedial action? Internal ExpertConsulting Service

    *1. Direct current voltage gradient method*2. Close interval potential survey*3. In-line inspection*4. Fitness-for-service

    (External Corrosion Direct Assessment; ECDA)

  • ECDA (External Corrosion Direct Assessment)ECDA (External Corrosion Direct Assessment)

    (CP) (CP) ,

  • - / (2003)

    1MPa / / 15 1MPa / / 15 5 .

    (Gas Transmission IM Rule), 49CFR192.923-931 (2003) 10 HCA (

    5 ) 7

    (ECDA) (pressure testing) e g In-line inspection (MFL-ILI) , e.g., In line inspection (MFL ILI)

    ASME B31.8S Section 6.4 ASME B31.8S Appendix B2 & A3

    NACE RP0502 (M th d l f ECDA) NACE RP0502 (Methodology for ECDA) Shall/Must Should Statements

  • ECDA ECDA PRE-ASSESSMENT

    INDIRECT EXAM.

    DIRECT EXAM.

    POST ASSESSMENT

    Risk Assessment

    (region)

    IMMEDIATE

    ( g ) CIPS/DCVG/

    SCHEDULEDMONITORING

    //

    SEVEREMODERATEMINOR

  • 1 1. - Pi l Pipe locator AC

    30m

    ECDA

  • Pre-assessment

    (,TB, ) :CIPS,DCVG,,PCM

  • 1 1. -

    Active/passive corrosion

  • 1 1. - 04-4

    03-303-404-104-204-3

    02 102-202-302-403-103-2

    00 401-101-201-301-402-1

    99 399-400-100-200-300-4

    1 2 3 4 5 6 7 8 9

    1

    0

    1

    1

    1

    2

    1

    3

    1

    4

    1

    5

    1

    6

    1

    7

    1

    8

    1

    9

    2

    0

    2

    1

    2

    2

    2

    3

    2

    4

    2

    5

    2

    6

    2

    7

    2

    8

    2

    9

    3

    0

    3

    1

    3

    2

    3

    3

    3

    4

    3

    5

    3

    6

    3

    7

    3

    8

    3

    9

    4

    0

    4

    1

    4

    2

    4

    3

    4

    4

    4

    5

    4

    6

    4

    7

    4

    8

    4

    9

    5

    0

    5

    1

    5

    2

    5

    3

    5

    4

    5

    5

    5

    6

    5

    7

    5

    8

    5

    9

    6

    0

    6

    1

    6

    2

    6

    3

    98-398-499-199-299-3

    4 4 4 4 4 4 4 4 4 4

    T/B NO.-2,500 --2,000 -2,000 --1,500 -1,500 --1,000 -1,000 --500 -500 -0

  • 1 1.

  • ()ECDA 1 ECDA 2 ECDA 3 ECDA 4 ECDA 5ECDA 1 ECDA 2 ECDA 3 ECDA 4 ECDA 5

    CIPS

    PCM

    River

    CIPS/DCVG PCM CIPS/DCVG

    Sandy-Loam Sandy Sandy Loam

    River

    Sandy Loam

    Medium

    No History

    Sandy

    Well Drained

    Low

    Sandy

    Well Drained

    Med. Resist.

    Loam

    Poor Drainage

    High

    No History Some Problems Many Problems

  • 1 2 3 CIPS(2) DCVG (ASP)

    / CIS DCVG

    , (6) 50m, CIS PCM DCVG1. , 40-50m CIS2. 30m SCM3 1 2 DCVG3. 1, 2 DCVG

    CIS DCVG (4)(5)(6) CIS DCVG , (4) CIS DCVG

    CIS DCVG

    1 CIS CIS PCM DCVG

    1. CIS 2. 30m SCM 3. DCVG

    Steel casing GSD 2124g () CIS DCVG encasement CIS DCVG

  • () () NACE RP0502 OO UNITS CpIS (ICCP) 1 - 3 m - 1.2-3m

    -

    mV (CSE)

    DCVG 1 2 m % IR - / (dip) %IR

    %IR Cathodic/anodic

    cathodic/anodic

    - %IR

    Resistivity , 1/3 2/3

    (50m)

    cm(Wenner 4-pin method or soil box)

    1/3, 2/3,

    (50m)

    PCM 18 45 20 PCM 18 45 m, 3 5 m

    20mCIPS ,

    (mA)

  • 2 2. - TB, , ,

    TB

  • 2 2. -

    (m) (mVCSE)

    M01 6 -498 -511 -503

    M02 864 126 -59 22

    M03 1386 180 -5 88 TPM04 2028 230 70 150

    M05 2970 540 100 320

    M06 3186 168 -227 -24

    M07 3732 920 560 740

    M08 4494 84 432 285M08 4494 -84 -432 -285

    M09 4908 148 -299 -97

    M10 5748 -181 -598 -412

    M11 5976 -219 -705 -432 TP

    - (TB)

    M12 6762 -235 -535 -427

    M13 7488 -207 -483 -361

    - (TB) - 600m-1Km 13

  • 2 2. -

    (< ~5,000 ohm.cm)

    Wenner four pin Method Wenner four pin Method ~200m

  • 2 (CIPS)2. (CIPS)

    s

    120od

    Ls

  • CIPS ()CIPS ()

  • CIPS ()CIPS ()

  • CIPS (25 ft to 5 ft)CIPS (25 ft to 5 ft)5 ft interval

    25 ft interval

  • 2 2. - .

    DCVG DCVG

  • 2 2. -

    Mg ( )

  • DCVG/CI Side DrainageDCVG/CI - Side Drainage

    115

  • DCVG - %iRDCVG - %iR

    5 ft interval

    25 ft interval

  • %IR (NACE RP0502 2002)%IR (NACE RP0502-2002) Category 1: 1-15% IR:

    .

    Category 2: 16-35% IR: , . . .

    Category 3: 36 60% IR: Category 3: 36-60% IR:

    Category 2 .

    -Category 4: 61-100% IR: .

    117

    .

  • 1995-2002 DCVG

  • DCVG GPS SystemDCVG-GPS System

    120

  • CIPS/DCVG CIPS/DCVG

    PDAGPS Antenna Bluetooth communication

    Push switchMeasure cablePDA screen touch operation

  • Pipeline Current Mapper(PCM) 4-8Hz ,

    Pipe locator receiver (receiver

    )

    ( ), ( ) ( )

  • Case I. ,

    Case II. , ,

    Case IIICase III./ ,

    Case IV. short

    C VCase V

    Case VI ,/

  • PCM OO PCM OO transmitter , 4Hz, 1A

    ( ) , loss

    transmitter Receiver

  • PCM PCM

    100TB1 TB2 TB3 TB4

    60

    70

    80

    90

    -

    30

    40

    50

    d

    B

    m

    A

    0

    10

    20

    0 500 1000 1500 2000 2500 3000 3500 4000 4500Distance,m

    TB DEFECT

  • 2 ( )2. ( ) (static or dynamic) -

  • ( ) (- ) - 0

    () +()(STA 29+37.91)

    -300

    STA 73 80V 9A

    900

    -600

    E

    ,

    m

    V

    -1200

    -900

    -1500

    -15 -10 -5 0 5 10 15

    Distance, m

    - ,

    - : ~0.2A ( 9A 2.2%)

  • Carrier pipe casing Carrier pipe casing

    128

  • CIS survey: river-crossing region DGPS coordinates measurement Stray current mapperCIS survey: river-crossing region

    0

    DGPS coordinates measurement Stray current mapper(SCM)

    -1,500

    -1,000

    -500

    -3,000

    -2,500

    -2,000

    0 20 40 60 80 100 120 140 160 180 2000 20 40 60 80 100 120 140 160 180 200

    No drilling DrillingCIS survey: asphalt road

  • -800

    -600

    -400

    -200

    0

    -2000

    -1800

    -1600

    -1400

    -1200

    -1000

    250%IR

    CIPS

    0 300 600 900 1200 1500 1800 2100 2400 2700 3000 3300 3600

    150

    200

    %IR

    %IR

    0

    50

    100

    0 300 600 900 1200 1500 1800 2100 2400 2700 3000 3300 3600100000

    1001000

    10000

    1

    10

    0 300 600 900 1200 1500 1800 2100 2400 2700 3000 3300 36002500

    PCM2A 2A 2A

    1000

    1500

    2000

    PCM

    0

    500

    1000

    0 300 600 900 1200 1500 1800 2100 2400 2700 3000 3300 3600

    PCM

  • CP Effectiveness (Pipeline Integrity) AssessmentCP Effectiveness (Pipeline Integrity) AssessmentField Survey

    TB34

    TB3TB33

    TB35

    TB2TB23

    Pipe locator/SCMPipe Location

    CP History

    TB23

    T1

    TB26TB27

    TB30

    TB28

    TB29

    TB31

    TB32

    3TB25-1TB25

    TB24

    T2TB23-2TB23

    -1

    y

    Rectifier/Test Point/Insulation FlangeInsulation Survey

    Resistivity/Water 0

    Resistivity/Water Content/MIC etc.Soil Corrosivity

    CIPS/DCVG/PCM3433323130

    282726

    25-12523-2T223-1T1

    23

    -2500

    -2000

    -1500

    -1000

    -500

    P

    o

    t

    e

    n

    t

    i

    a

    l

    (

    V

    C

    S

    E

    )

    D2-8

    -0.75V

    -0.85V

    D2-9

    Steel CasingDC/AC Interference, etc.Special Region Exam.

    Risk Assessment

    2924

    -30000 500 1000 1500 2000 2500 3000 3500 4000 4500

    Distance from TB 23 (m)

    Risk Assessment

    Mitigation Action

    Documentation

  • DIRECT EXAMINATION DIRECT EXAMINATION (urgency of excavation)

    (Immediate action required) (Schedule for action required) (Suitable for monitoring)

    / feedback

  • (1 good coating) (1 good coating)1: DCVG*DCVG + Severe Moderate Minor NI

    < 3,000 I* S* S* M*

    3,000 7,000 I* S* M* M*(cm)

    , ,

    7,000 20,000 I* S* M* NI*

    > 20,000 S* M* M* NI*

    2: 1 1 + CIPS I* S* M* NICIPS Severe I S S M

    Moderate I S M M

    Minor I S M NI

    NI S M M NI

    * I: Immediate ( ) S: Scheduled ( ) M: Monitoring ( ) I: Immediate ( ), S: Scheduled ( ), M: Monitoring ( )

  • (2 poor coating) (2 poor coating)

    (minor) (moderate) (severe)

    CIPS -0.75V < off < -0.65V Off > -0.65V

    > 10,000 cm 5,000 10,000 cm < 5,000 cm

    CIPS I II

    III

    IV V

  • / pH / p () ()

  • () (monitoring)() ( monitoring )

    Coating defect found No disbonding Defect was protected perfectly by CP.

  • () (scheduled)() (scheduled)

    Disbonded area Mechanical Damage Coating disbondment

    No corrosion at crevice openingCorrosion occurred inside creviceDepth of disbondment: about 15 cm.

    Crevice opening: pH>11Inside crevice: pH 6-7

  • () (immediate)() ( immediate )

    pH pH (mV) (cm) STN

    1

    7 604 6 513

    :10,362cm2

    1 7 -604 6,513 :56cm2

    : 12 25 70 2

    2

    7~9 -735 2,098:25 ~ 70cm2

    : 12, 7

    3

    8 -562 2,538

    :10,362cm2

    :1,602cm2

    :5.4 ~ 6.1cm2

    4

    8~9 -701 1,360

    , , :7.6cm2~47cm2

  • Is corrosion is active or passive?Is corrosion is active or passive?

    CASE 1: Active corrosion CASE 2: Passive corrosion

    Types Potential (mV/CSE)

    Pipe-to-Soil Potential -1430 to -1200

    Potential inside crevice -610 to -550

    OFF OFF

  • pH pH

    , OH- pH

    OHHeOH 222 22 pH 1) 2) pH (

    ) )

    3) pH pH

    pH pH>10~11

    . vs. pH

    ,

    . p pH< 8

    , pH

    .

  • 4 4.

    ECDA

  • Maximum pit depth/burial time 0.4 mm/y*1

    0 3 / l 0 C 0.3 mm/y at least 40mV CP

    LPR measurement (ASTM G59) + pitting index LPR measurement (ASTM G59) + pitting index Corrosion coupon

    *1. Upper 80% confidence level of maximum pitting rates for long term (up to 17y) underground corrosion tests ofbare pipe coupons without CP in a variety of soils including native and non-native backfill.

  • tSM850RL PP

    GRt

    SM85.0RL YIELD

    MAOP

    YIELD

    FAIL

    PP

    PP

    SM FOR: YIELDYIELD

    3300

    FOR:

    SM (safety margin) = 0.6

    GR () = 10 mil/yr.yr8.16

    010.330.0

    )6(.85.0RL ( ) /y

    T () = 0.330

    1/2 ECDA !!!

  • ECDA DCVG ECDA DCVG .

    DCVG , ECDA .

    . DCVG ECDA .

    ECDA , , feedback

  • Availability of ECDA Tools (cf NACE RP0502)Availability of ECDA Tools (cf. NACE RP0502)CIPS DCVG Pearson EM AC Attenuation

    Coating holidays 2 1,2 2 2 1,2

    Anodic zone or bare pipe 2 3 3 3 3

    Near river or water crossing 2 3 3 2 2

    Under frozen ground 3 3 3 2 1,2

    S 2 1 2 2 2 1 2Stray currents 2 1,2 2 2 1,2

    Shielded corrosion activity (heat-shrink sheet) 3 3 3 3 3

    Adjacent metallic structures 2 1,2 3 2 1,2

    Near parallel pipelines 2 1,2 3 2 1,2Near parallel pipelines 2 1,2 3 2 1,2

    Under HVAC overhead electric transmission lines 2 1,2 2 3 3

    Shorted casing 2 2 2 2 2

    Under paved roads 3 3 3 2 1,2

    Uncased crossing 2 1,2 2 2 1,2

    Cased piping 3 3 3 3 3

    At deep burial locations 2 2 2 2 2

    W tl d (li it d) 2 1 2 2 2 1 2Wetlands (limited) 2 1,2 2 2 1,2

    Rocky terrain/rock ledges/rock backfill 3 3 3 2 2

    *1: - (

  • Corrosion under Disbonded CoatingCorrosion under Disbonded Coating

    147

  • PtRef2PipeRef1 p

    1. Ref 1 vs. Pipe 2. Ref 2 vs. Pipe 3. Ref 2 vs. Pt

    Potential mV vs. Cu/CuSO4

    P/S -1430 (-1200)

    In Crevice -610 (-500)

    Pt Electrode -480

    Redox -160 (vs. NHE)*1

    *1 At H 7

    148

    *1. At pH 7

  • C i P t ti l M t U d Di b d d C tiC i P t ti l M t U d Di b d d C tiCrevice Potential Measurement Under Disbonded CoatingCrevice Potential Measurement Under Disbonded Coating

  • Holiday potential -1.0V/CSE

    NaCl 0.001M, 8350cm NaCl 0.005M, 1755cm NaCl 0.05M, 195cm

  • : /

  • Disbonded coating (PUF), DCVG ( )/ / ( )

  • ECDA + ILI ()

  • ILI (GRI 02/0087) ILI (GRI-02/0087) 33% ILI (2002)

    75% ILI 40 ( )

    25% unpiggable ILI

    ECDA (25% (42%)) ECDA . (25% + (42%))

  • ECDA+ILI (KOGAS )ECDA+ILI (KOGAS ) /

    Geometry pig

    ILI /(Defect Assessment)

    Geometry pigMFL pig

    (CIPS)

    /

    ()

    (ECDA)/

  • ILI-MFLILI-MFL

    . (threshold value)

    .

  • GPS WirelessGPSGIS

    Satellite Communication

    WirelessNetworks

    Rectifier RectifierTB 1 TB 2

    Remote Remote

    ReferenceElectrode

    ReferenceElectrode

    Remote MonitoringData Logger

    Remote ControlRectifier

    Remote MonitoringData Logger

    Remote ControlRectifier

    ElectrodeElectrode

    Anode AnodeCurrent

    157

  • [ ] [ ]

    SCR type SMPS typeSCR type SMPS type

    - (on/off) GPS 10 msec

  • Installation & Operation Status in KoreaInstallation & Operation Status in Korea

    Gas transmission pipelines Gas transmission pipelines ~150 km of total 3,000 km is covered by

    RemoteCPMSTM

    Municipal water pipelines Municipal water pipelines ~50km of total 3,000km is covered

    Samsung BP Chemical pipeline ~ 5km

    Gas distribution pipeline (Mokpo) 5km ~ 5km

    InstalledPlanned (2009)FutureFuture

  • Economic Feasibility Study on Remote CP MonitoringExample: CP Maintenance Cost for Water Pipelines in Koreap p

    80

    60

    70 Remote MonitoringManual Maintenance

    50

    C

    o

    s

    t

    30

    40

    R

    e

    l

    a

    t

    i

    v

    e

    20

    Assumption:

    10Assumption:- Lifespan: 15 y- One rectifier + Two TB in 2km region

    0 5 10 15 20 25 30

    Operation Period (yr)

  • 10

    9

    8OO

    = -2.5VCSE(-), (+) 7

    6

    R

    T

    CW ()

    5

    4

    OOOO

    OO

    3

    2

    2

    1

    OO

  • vs. 4 2

    3 P/S 4 P/S 2 P/S

    35+25=60(A)35+25=60(A)

  • / /

  • 16

    M MCIPS (data logger)

    (#13, #26, #28, #30)

  • () ()R19 on/off, 25 (on/off 27mV) R15 on/off, 13 (on/off 192mV)

    R18 on/off, 21 (on/off -1756mV) / , ( / )

    R17 on/off, 17 (on/off -74mV)

    20mV

  • () () (m R1 R2 R3 R4 R5 R7 R8 R9 R11 R12 R13 1 R13 2 R13 3 R14 R15 R17 R18 R19 R20 R21 R22 R23 R24 R25

    ) R1 R2 R3 R4 R5 R7 R8 R9 R11 R12 R13-1 R13-2 R13-3 R14 R15 R17 R18 R19 R20 R21 R22 R23 R24 R25

    30 -1000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 13 6 M1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 192 0 0 0 0 0 0 0 0 0 14 864 M2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 36 0 0 0 0 0 0 0 0 0 15 2028 M4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 28 0 24 0 0 0 0 0 0 28 18 2364 0 0 0 0 0 0 0 0 0 0 0 0 0 0 69 50 36 0 0 0 0 0 0 30 16 2970 M5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 29 0 43 0 0 0 0 0 0 45 17 3186 M6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 31 -74 100 0 0 0 0 0 0 43 19 3504 D2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -23 94 0 0 0 0 0 0 0 20 3732 M7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -22 208 0 0 0 0 0 0 0 21 4380 0 0 0 0 -200 0 0 0 0 0 0 0 0 0 0 0 -1756 0 0 0 0 0 0 0 22 4908 M9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 258 0 26 0 0 0 0 022 4908 M9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 258 0 26 0 0 0 0 0 23 5748 M10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 43 0 0 0 0 0 24 6762 M12 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 49 29 0 0 0 0 0 25 7488 M13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 27 0 0 0 0 0 0 26 7650 End 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 43 0 0 0 0 0 0 28 8650 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 76 0 0 0 0 0

  • , () (ECDA,

    ILI )

    IT ()

  • () () Design can never be absolute.

    A designer is seldom a corrosion engineer. Unlike conventional engineering, the basic difficulty is that

    corrosion is not a tangible propertycorrosion is not a tangible property. Decisions are often a compromise based on cost and availability of

    materials and resources.

    Communication is important.C i i f d f f il l Communication of agreed reasons for failures may not always reach the designer. (ASM Metals Handbook, Vol. 13A) Site personnel: 77%p Designers: 55% Materials suppliers: 37%

    C t t 11% Contractors: 11%

  • THE ENDTHE END