Advances In Pipeline Materials, Welding, and Inspection

by

Robin GordonEWI, Columbus, Ohio, USA Presented atFirst Annual PRCI R&D ForumApril 8, 2003

Pipeline Design and ConstructionMany new major Oil and Gas reserves are in remote locations and will require the construction of long distance pipelines.Pipeline construction costs can exceed:$1M - $1.5M per mile for cross country pipelines$3M - $5M per mile for offshore pipelinesIn many cases the cost of pipeline construction dominates the economics of Oil and Gas recovery.In addition to the capital investment associated with new pipeline construction, there is a need to extend pipeline design methods to cover increasingly demanding operating requirements.

Pipeline Industry - Business DriversReduce the cost of new pipeline design, construction, and operation without compromising pipeline integrity.Extend existing pipeline design codes to cover increasingly demanding operating requirements including strain-based loading.

Presentation OutlinePipeline Cost ReductionHigh Strength Pipe MaterialsHigh Productivity WeldingAdvanced NDE Methods

Pipeline DesignStrain-Based Design

Pipeline Construction CostsMaterials (Linepipe)OtherWelding & Inspection

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Pipeline Cost ReductionTechnology Options include:High Strength PipeReduced Material CostsHigher Operating PressuresHigher Design FactorsHigher Operating PressuresHigh Productivity Welding / InspectionImproved Construction Methods & Equipment

High Strength Pipelines - X80, X100, X120Current StatusX80 Pipeline TechnologyProven methods for X80 pipe productionGood material properties (including crack arrest)Proven construction methodsCross country X80 pipelines constructed in Europe and CanadaOffshore X80 pipelines are becoming increasingly common (pipeline, flowlines, and risers)SummaryX80 Pipeline Technology is Mature

High Strength Pipelines - X80, X100, X120Current StatusX100 Pipeline TechnologyX100 Pipeline Technology is at an advanced stage of development and demonstration.Crack arrest performance is still not fully proven, particularly for high pressure applications.TCPL constructed an X100 pipeline loop in the Fall of 2002 to gain experience with field construction.X120 and BeyondMajor proprietary R&D program to develop and assess X120 and X120+ pipeline technology.Initial results are very encouraging.

High Strength Pipelines - CRLPCurrent StatusComposite Reinforced Linepipe (CRLP) Technology CRLP is an alternative to high strength linepipeCRLP offers excellent crack arrest performance.Field Construction methods have been developed.Long term performance of composite wrap not fully proven.Composite wrap cannot be inspected or monitored using conventional in-line inspection methods.CRLP may not be suited to strain based design (i.e., pipelines that may experience high strains in service)

High Strength Pipeline - R&D PrioritiesNear TermDevelop and Validate X100 Pipeline TechnologyPipe Production and Pipe PropertiesValidate Construction Methods (Field Welding)Operational Integrity (Fitness for Service)Medium TermDevelop and Validate CRLP TechnologyLong Term Structural PerformanceLong Term Corrosion PerformanceStrain Based LoadingMonitoring and in-line inspection (embedded sensors)Long TermDevelop and Assess X120 Pipeline Technology

High Productivity Pipeline WeldingHigher pipeline welding productivity can be achieved through a combination of:High Speed Root Pass WeldingHigh Productivity Fill Pass WeldingHigh Speed Root Pass WeldingOptions include Laser / GMAW Hybrid Welding or advanced Automated GMAW Welding (VP-GMAW).High Productivity Fill Pass WeldingOptions include Laser / GMAW Hybrid Welding or Dual Tandem GMAW Welding (e.g., CAPS)

Schematic of Hybrid Process Used

CAPS Welding System

High Productivity Welding - Future R&DNear TermContinue to validate high productivity GMAW Welding for High Strength PipelinesWelding productivity and weldabilityConsumable developmentWeld joint characterizationDevelop process monitoring capabilitiesMedium Term Continue to monitor Laser Welding DevelopmentsLong TermMonitor and evaluate future developments with new high productivity and / or single shot welding methods.

Pipeline Girth Weld InspectionCurrent StatusAutomated Ultrasonic Testing (AUT) is now recognized as the preferred inspection method for new pipelines.AUT system performance is generally very good although there is uncertainty as to the actual performance (POD & Sizing Errors) of AUT.Phased Array AUT Technology has been introduced in the last few years for pipeline inspection and appears to offer improved performance.There is a need to determine the limits of AUT and Phased Array AUT (particularly for larger wall thickness pipes) to verify fitness-for-service design methods and ECAs

Pipeline Girth Weld Inspection - R&D PrioritiesNear TermCompare performance of AUT and Phased Array AUT NDE for pipeline girth weld inspection:Probability of DetectionSizing ErrorsMedium TermAssess Performance of AUT and Phased Array AUT for heavy wall high pressure pipelines.Long TermExtend and improve Phased Array AUT Technology

Pipeline DesignCurrent StatusThe majority of pipeline design codes are based on stress based design methods. Although conventional stress based design covers most pipeline applications, it does not cover the design of pipelines that may experience high strains in service. High strains can occur in service due to ground movement, bending over an unsupported span and seismic loading. In such cases pipelines should be designed based on strain capacity. Girth welds can be source of strain localization and can be a limiting factor in strain based design.

Pipeline Design - R&D PrioritiesNear TermDevelop and validate ECA and strain based design methods for cross country and offshore pipelines.Design Guidance (Material Selection, Welding Recommendations, Full Scale Validation)ECA Guidance (Material Property Characterization, FFS Models)Medium TermIncorporate strain based design methods with overall pipeline reliability methods.

SummaryThe cost of pipeline construction can be reduced through the adoption of next generation technologies. High Strength PipeHigh Productivity WeldingAdvanced Inspection MethodsHigher Design Factors and Operating PressuresMaximum benefit obtained by adopting multiple parallel technologies simultaneously.New Oil and Gas discoveries in remote geographically demanding regions will require the development of new improved design methods for pipelines.