fatigue performance of high strength riser materials rpsea project no. dw 1403
DESCRIPTION
Fatigue Performance of High Strength Riser Materials RPSEA Project No. DW 1403 TAC Quarterly Meeting June 2, 2009 Houston, Texas Presented by Stephen J. Hudak, Jr. Materials Engineering Department Southwest Research Institute. Research Partnership to Secure Energy for America. - PowerPoint PPT PresentationTRANSCRIPT
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Fatigue Performance of High Fatigue Performance of High Strength Riser MaterialsStrength Riser Materials
RPSEA Project No. DW 1403RPSEA Project No. DW 1403
TAC Quarterly MeetingTAC Quarterly MeetingJune 2, 2009June 2, 2009
Houston, TexasHouston, Texas
Presented byPresented byStephen J. Hudak, Jr.Stephen J. Hudak, Jr.
Materials Engineering DepartmentMaterials Engineering DepartmentSouthwest Research InstituteSouthwest Research Institute
Research Partnership to Secure Energy for America
22
Project ObjectiveProject Objective
Assess the fatigue resistance of new Assess the fatigue resistance of new high strength HPHT riser materials in high strength HPHT riser materials in representative environmentsrepresentative environments
• Fatigue Crack Growth Rates (FCGR)• Classical S-N fatigue life
• EnvironmentsAir (baseline)Sour brineSeawater
33
MaterialsMaterialsMaterialMaterial YS, ksiYS, ksi SourSour StatusStatus
11 114 ksi 114 ksi yesyes Specimens machined; Specimens machined; frequency-scan tests completefrequency-scan tests complete
22 131 ksi 131 ksi yesyes Specimens machined; Specimens machined; frequency-scan tests completefrequency-scan tests complete
33 ~125 ksi ~125 ksi yesyes Awaiting materialAwaiting material
44 132 ksi 132 ksi nono Specimens machined; Specimens machined; frequency-scan tests completefrequency-scan tests complete
55 156 ksi 156 ksi nono Specimens being machinedSpecimens being machined
66 ~120 ksi ~120 ksi yesyes Awaiting materialAwaiting material
44
EnvironmentsEnvironments Lab air (baseline):Lab air (baseline): 70-75°F, 40-60% RH 70-75°F, 40-60% RH
Seawater:Seawater: ASTM D1141 substitute ocean ASTM D1141 substitute ocean water open to the air with cathodic water open to the air with cathodic protection: - 1050mv vs. Saturated protection: - 1050mv vs. Saturated Calomel ElectrodeCalomel Electrode
Sour Brine:Sour Brine: Production brine with oxygen Production brine with oxygen below 10 ppb and 35% Hbelow 10 ppb and 35% H22S + 65% COS + 65% CO22
55
Task 1: FCGR TestingTask 1: FCGR Testing
Frequency scan (FS) tests at Constant-Frequency scan (FS) tests at Constant-K K to determine optimum cyclic loading to determine optimum cyclic loading frequency for subsequent testingfrequency for subsequent testing
FCGR testing as a function of FCGR testing as a function of K to K to determine cracking kinetics that can be determine cracking kinetics that can be used in fracture mechanics design and/or used in fracture mechanics design and/or fitness-for-service assessmentsfitness-for-service assessments
66
FCGR SpecimenFCGR Specimen
77
MaterialYSksi
AirTests
Seawater PlusCP Tests
Sour BrineTests
ApplicationsTargeted
6 ~120 (data available) (data available) 2plus 1-f scan
SCR, Hybrids,Dry tree
1* 114 2 2plus 1 f-scan
2plus 1-f scan
Inner Casing,SCR, Hybrid
2* 131 2 2plus 1 f-scan
2plus 1-f scan
Outer, Inner Casing,SCR, Hybrid
3 ~125 2 2plus 1-f scan
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plus 1 f-scanplus 1 f-scan
Outer, inner Casing, SCR, Hybrid
4* 132 2 2plus 1-f scan
Outer Casing, Non-Sour SCR/ Hybrid
5* 156 2 2plus 1-f scan
Outer Casing, NonSour SCR/ Hybrid
Total FCGR tests 10 15 9+3 Grand Total: 34+3
Orange = tests completed Red = tests not in current SOW
Task 1: FCGR Test MatrixTask 1: FCGR Test Matrix
* Materials in-hand
Crack Length, in.
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
da/
dN
, in
./cy
cle
10-6
10-5
10-4
10-3
10-2
10 Hz - air10 Hz - seawater1Hz - seawater0.33 Hz - seawater0.1 Hz - seawater0.01 Hz - seawater
YS = 132 ksiSeawaterK=20 ksiinR=0.5
88
Frequency Scan TestingFrequency Scan Testing
Corrosion fatigue Corrosion fatigue performance performance sensitive to loading sensitive to loading frequencyfrequency
Fatigue crack Fatigue crack growth rates at growth rates at constant-constant-K used K used to characterize to characterize frequency effect in frequency effect in frequency scan (FS) frequency scan (FS) teststests
13x
Seawater
Seawater vs. Sour BrineSeawater vs. Sour Brine
99
Crack Length, in.
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
da/
dN
, in
./cy
cle
10-6
10-5
10-4
10-3
10-2
10 Hz - air10 Hz - seawater1Hz - seawater0.33 Hz - seawater0.1 Hz - seawater0.01 Hz - seawater
YS = 114 ksiSeawaterK=20 ksiinR=0.5
6X
Seawater
Crack Length, in.
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
da/
dN
, in
./cy
cle
10-6
10-5
10-4
10-3
10-2
10 Hz - air10 Hz - sour brine1Hz - sour brine0.33 Hz - sour brine0.1 Hz - sour brine0.01 Hz - sour brine
YS = 114 ksiSour BrineK=20 ksiinR=0.5
24X
Sour Brine
YS = 114 ksi
Seawater vs. Sour BrineSeawater vs. Sour Brine
1010
YS = 131 ksi
Crack Length, in.
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
da/
dN
, in
./cy
cle
10-6
10-5
10-4
10-3
10-2
10 Hz - air10 Hz - seawater1Hz - seawater0.33 Hz - seawater0.1 Hz - seawater0.01 Hz - seawater
YS = 131 ksiSeawaterK=20 ksiinR=0.5
Seawater
15X
Crack Length, in.
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
da/
dN
, in
./cy
cle
10-6
10-5
10-4
10-3
10-2
10 Hz - air10 Hz - sour brine1Hz - sour brine0.33 Hz - sour brine0.1 Hz - sour brine0.01 Hz - sour brine
YS = 131 ksiSour BrineK=20 ksiinR=0.5
250X
Sour Brine
Yield Strength, ksiYield Strength, ksi
114 131 132114 131 132
Material-Environment InteractionsMaterial-Environment Interactions
1111
Environment:Environment:
Sour BrineSour Brine
SeawaterSeawater
24X 250X ---
6X 15X 15X
Corrosion-Fatigue Acceleration* vs. Air Baseline
* At K= 20 ksi√in. R=0.5 and Frequency = 0.01 Hz
Frequency Response vs. YS Frequency Response vs. YS
1212
Cyclic Frequency, Hz
0.01 0.1 1 10
Ave
rag
e d
a/d
N, i
n./c
ycle
10-6
10-5
10-4
10-3
10-2
Sour BrineK = 20 ksiinR=0.5
green: YS = 131 ksiblue: YS = 114 ksi
Sour Brine
Air Baseline
Cyclic Frequency, Hz
0.01 0.1 1 10
Ave
rag
e d
a/d
N, i
n./c
ycle
10-6
10-5
10-4
10-3
10-2
SeawaterK = 20 ksiinR=0.5
green: YS = 131 ksiblue: YS = 114 ksi
Seawater
Air Baseline
Procured four of six test materials – at no cost to projectProcured four of six test materials – at no cost to project Completed specimen machining on three of six materialsCompleted specimen machining on three of six materials Specimen machining on fourth material is in-progressSpecimen machining on fourth material is in-progress Completed frequency scan tests on 62% of material-Completed frequency scan tests on 62% of material-
environment combinationsenvironment combinations Analyzed frequency-scan data and identified the importance of Analyzed frequency-scan data and identified the importance of
material strength level on corrosion-fatigue resistancematerial strength level on corrosion-fatigue resistance Determined that saturation frequency likely depends on Determined that saturation frequency likely depends on
material-environment combinationmaterial-environment combination Machined grips for baseline air tests to be performed at NETL-Machined grips for baseline air tests to be performed at NETL-
Albany, OregonAlbany, Oregon Initiated air S-N testing at SwRI to assess inter-laboratory Initiated air S-N testing at SwRI to assess inter-laboratory
reproducibility with NETLreproducibility with NETL Took receipt of ConocoPhillips Ti-alloy data baseTook receipt of ConocoPhillips Ti-alloy data base
1313
Last-Quarter ProgressLast-Quarter Progress
1414
ScheduleSchedule
1515
CostsCosts
RPSEA Contract AmtRPSEA Contract Amt$800K$800K
BP Cost ShareBP Cost Share $200K$200K
Total Contracted Amt $1,000KTotal Contracted Amt $1,000K
Costs to DateCosts to Date $218K$218K
BalanceBalance $782K$782K
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Next-Quarter PlanNext-Quarter Plan Procure remaining two test materialsProcure remaining two test materials Machine remaining specimensMachine remaining specimens Complete frequency-scan testsComplete frequency-scan tests Meet with PWC to select optimum test frequenciesMeet with PWC to select optimum test frequencies Complete air S-N tests at SwRIComplete air S-N tests at SwRI Initiate air S-N tests at NETLInitiate air S-N tests at NETL Initiate seawater S-N testsInitiate seawater S-N tests Initiate sour brine S-N testsInitiate sour brine S-N tests Initiate air FCGR testsInitiate air FCGR tests Initiate seawater FCGR testsInitiate seawater FCGR tests Initiate sour brine FCGR testsInitiate sour brine FCGR tests