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8/11/01 Data Integration 1
Alyeska Experience with Data Integration on Trans Alaska Pipeline
Experience with Data Integration on theTrans Alaska Pipeline
8/11/01 Data Integration 2
TAPS Background
800 Mile - Crude Oil Transmission Pipeline North Slope to Valdez Alaska 48 “ Dia. 0.5” wall thickness Three Construction Modes to Consider
376 Miles Conventional Below Ground pipeline 420 Miles Above Ground to avoid unstable permafrost 4 Miles Insulated/Refrigerated Buried
System Startup - August 1977 24 Yrs of Operation 2.1 MMBPD Capacity, 1.0 MMBPD Throughput Over 13 B bbls transported
8/11/01 Data Integration 3
TAPS ILI Background
TAPS - History of In Line Inspection (ILI) Annual Inspections Since 1979 58 Smart Pig Runs over operating life Both UT and MFL wall loss pigs used - UT is now primary
tool Curvature/Deformation Pigs used
Predominate Operating Risks Addressed by ILI Corrosion Settlement/Curvature Deformation/Third Party damage -
During construction and operation
8/11/01 Data Integration 4
Experience with Data Integration
Data Integration Depends on Decisions Required Focus on Decision Support not just Data Management
A Management System needed - to manage changes Decisions Based on Risk - Contain Uncertainty
Decisions depend on defect type Corrosion, Dents, Curvature, Interaction of defects
Decisions depend on pipeline location and data limitations High Risk v Normal Risk Locations
Intervention Criteria Based on Risk
Interaction with ILI Vendors a Must Pig Data Can Be Used to Assess Cathodic Protection
8/11/01 Data Integration 5
Data Integration Description
Oracle Data Base - Intranet Application- By Pipe Joint (Contains 105,000) Pipe Data - Grade, Thickness, MAOP, Hydrotest data, Bend data, Mode Pipe Features - Insulation, Casing, Coating, River Weights, etc, Hydraulics Data - Functional MOP Pig Data - Corrosion/Curvature/Deformation - Contains Graded, Not Raw Data, CP Data - CIS, CP Coupon Data
Embeds Routine Queries and Decisions Corrosion Defect Evaluations, RSTRENG
Outputs Routine Reports Ranking by penetration, bursting pressure, SF, Years to Dig, Etc. Integrated Data Displays - GIS not mandatory
Contains Information needed for Maintenance Decisions
8/11/01 Data Integration 6
Management System Elements
A management system is needed to manage change Alyeska Integrity Management System (AIMS) has 5
elements
Scope & Objectives defined Secure, readily accessible environment Allows Accurate and efficient maintenance decisions Distributes data in a single source Maintains a record of decisions made
Procedures written Data Collection, Quality Assurance, Security etc.
8/11/01 Data Integration 7
Mgmt System Elements (Cont)
Accountable Resources - Roles Defined Data Base Developer Data Base Administrator Data Owners, Data Entry System Users IT Maintenance Support
Data Management Performance Measures established Based on Objectives
Feedback Processes established AIMS Assessment - Improvement of Decision Support Management Plan Risk Assessment - Assess risks e.g. bad algorithm, data corruption, human error Technology Assessment - Take advantage of new technologies, i.e. GIS Compliance Assessment - Adapt to new regulations, new industry standards Business Assessment - Strategic planning and budgeting
8/11/01 Data Integration 8
Defect Types and Failure Modes
Corrosion Penetration Bursting
Dents Outside Force/Third Party Damage - Top Half of Pipe Bottom Half of Pipe -
Dents w Stress Riser (Metal Loss or Contact with Weld)
Curvature and Curvature w Corrosion Straight Pipe Field Bends
8/11/01 Data Integration 9
Risk Classification Sets Urgency
Decisions depend on Risk Consequences depend on pipeline location Data Limitations increase risks (pig data, CP data)
High Risk Areas - 6 different types DOT High Consequence Areas ~ 40 miles
Locations where leak “Could Affect” • Commercially Navigable Waterways• High or Other Population Areas• Unusually Sensitive Areas - Endangered Species
Other (Discretionary) High Consequence Areas ~ 20 miles Locations “Within”
• Major Streams or Floodplains• Inaccessible Areas
8/11/01 Data Integration 10
Action Urgency (Continued)
High Risk Areas (Continued) Areas where Pig Performance is Limited ~ 15 miles
Near Welds, 3D Bends, Slack Line, Wax affected locations
Active Corrosion Areas - 9 miles Statistically Active Corrosion, High projected corrosion
Areas with Limited Cathodic Protection - 5 miles Under Insulation, Shorted Casings, Known Disbonded Coatings
Notably Corroded Areas - 1 mile High Probability of Exceedance, Potential for NAC, SCC, MIC
Normal Risk Areas - Other areas not designated “High Risk” 90/800 miles (11%) designated high risk
8/11/01 Data Integration 11
Intervention Criterion (Triage)
No Action - Required Intervene - Corrective Maintenance within Year of
Discovery1 or as required by regulation Expose pipe, evaluate defect, repair if necessary lower operating pressure
Investigate - Predictive Maintenance within 3 Years Rank Severity based on all available data Expose pipe, evaluate and repair in order of Severity Rank
Note1: Discovery Means - Data is available, of sufficient reliability, for an operator
to clearly determine that intervention is required.
8/11/01 Data Integration 12
Intervention Criterion (Cont)
High Risk Normal RiskDefect Type Investigate Intervene Investigate Intervene
Corrosion/Metal LossPenetration RWT < 65 % NWT RWT < 60% NWT RWT < 55 % NWT RWT < 50% NWT
Bursting YTD <= M*Inspct Intvl PRSTREN < 95 % MOP YTD <= 1*Inspct Intvl PRSTREN < 100 % MOP
Dent/OvalityTop Half Def > 0.75 in (1.5% Dia) Fatigue Unacceptable Def > 0.96 in (2% Dia) Fatigue Unacceptable
Bottom Half Def > 2.88 in (6% Dia) Fatigue Unacceptable Def > 2.88 in (6% Dia) Fatigue Unacceptable
Dent w Stress Riser Any Dent w Metal Loss If no mitigating factors Any Dent w Metal Loss If no mitigating factors
CurvatureStraight Pipe Curv > 70 % Kcr Wave Form > .25 in Curv > 85 % Kcr Wave Form > .25 in
Delta Curv > 10 % Delta Curv > 20 % Delta Curv > 10 % Delta Curv > 20 %
Field Bends Delta Curv > 10 % Delta Curv > 20 % Delta Curv > 10 % Delta Curv > 20 %
Wave Form > .25 in Wave Form > .25 in
Curvature w Metal LossStraight Pipe Curv > 70 % Kcr SAFE Unacceptable Curv > 85 % Kcr SAFE Unacceptable
Delta Curv > 10 % Delta Curv > 10 %
RWT < 65 % NWT RWT < 55 % NWT
YTD <= 2*Inspct Intvl YTD <= 1*Inspct Intvl
Field Bends Delta Curv > 10 % SAFE Unacceptable Delta Curv > 10 % SAFE Unacceptable
RWT < 65 % NWT RWT < 55 % NWT
YTD <= M*Inspct Intvl YTD <= 1*Inspct Intvl
8/11/01 Data Integration 13
Decision ProcessDecision Criteria High Risk Areas,
Defect Types,Intervention
Criterion, Min Digs
Pig Data
CDMCorrosion DataManagement
System
Start PigFeature
EvaluationProcess
FeatureExceeds
InvestigationCriterion
RecommendCorrective
Maintenance
FeatureExceeds
InterventionCriterion
PredictiveMaintenance
Ranking Process
IsRanking<
Minimum NoDigs
RecommendPredictive
Maintenance
ConductMaintenance
No ActionDocument Results
Update CDM
Corrective ActionDocument Results
Update CDM
Predictive ActionDocument Results
Update CDM
EndProcess
VendorInteraction
Criterion
Current Data
PreviousData
No
Yes
YesYes
No
YesYes
No ActionDocument Results
Update CDM No
EvaluateLessons Learned
8/11/01 Data Integration 14
Interaction Needs with ILI Vendors
Raw data interpretation by Operator needed
Pig Performance assessment Routine Coordination w Vendor Comparison between Field and
Pig data
Pig Run Type Begin End Deep Length DEG RWT 85%M RSTRENG
1998 NKK UT 3168678.9 3168688.3 3168688.1 4.8 221 362 1004 984
1997 NKK UT 3168687.6 3168689.8 3168688.1 26.4 222 335 849 958
1996 NKK UT 3168687.5 3168693 3168688 66 226 362 869
1994 Pipetronic UT 3168687.6 3168693 3168688 64.8 211 382 905
1992 Pipetronic MAG 3168687.9 316868802 3168688 3.6 212 370 1025
Field Analysis 3168687.8 3168691.8 3168688.1 48 216 365 882 954
8/11/01 Data Integration 15
CP Mitigation Decisions
Pig Data Can Be Used for more than dig decisions Statistically Active Corrosion -
Based on 100 foot Moving Average Pig Call Depth Identifies “Statistically Active Corrosion” (3-10 mpy vs 0-3 mpy) May indicate need for CP Mitigation in spite of Good CP Data
Projected Pig Features - “Years to Dig” Projected to determine number of corrosion investigations
likely in future. Economic Model Compares Cost of Corrosion Investigations vs.
Alternative Maintenance such as Additional CP or Coating Refurbishment.
Corrosion Data Overlays - GIS like display Used to Display Relevant Corrosion Data in one source Supports corrosion decision making and planning
8/11/01 Data Integration 16
Corrosion Data Overlays
8/11/01 Data Integration 17
Summary - Lessons Learned
Data Integration Depends on Decisions Required Focus on Decision Support not just Data Management
A Management System needed - to manage changes Decisions Based on Risk - Contain Uncertainty
Decisions depend on defect type Corrosion, Dents, Curvature, Interaction of defects
Decisions depend on pipeline location and data limitations High Risk v Normal Risk Locations
Intervention Criteria Based on Risk
Interaction with ILI Vendors a Must Pig Data Can Be Used to Assess Cathodic Protection
8/11/01 Data Integration 18