3. Marco teórico
3.2 La teoría del reconocimiento de Axel Honneth
3.2.2 Del menosprecio a la solidaridad en el entorno escolar
Committee: Pipeline Materials
Project Title:
Mechanical Damage Direct Assessment - RPTG-0321
-Author: L. Blair Carroll
Principal Researcher: L. Blair Carroll / Robert Lazor
Name of Organization: BMT Fleet Technology Limited (BMT FTL)
Project Type: New
1) Statement of the Problem (What is to be solved):
There are a number of tools and methods available for characterizing and assessing the structural significance of corrosion or cracking that are not directly applicable to mechanical damage. Such a tool for direct assessment will require the ability to combine the relative impact of several features of the mechanical damage, which include associated pipe deformation, gouging and the presence of other localized effects such as weld seams or corrosion. A mechanical damage assessment methodology will require consideration of stress analysis techniques, materials damage models and fracture mechanics based algorithms.
2) Background (What is the historical data):
A significant amount of research effort has been attributed to denting and mechanical damage. Programs of note include the API 1156 study and the GRI-97/0413 study.
In conjunction with industry support, BMT Fleet Technology has developed a Dent Assessment Model aimed at evaluating the impact of the presence of dents on the integrity of a pipeline. The model incorporates finite element analysis of the dented pipe geometry and a fracture mechanics based fatigue crack growth algorithm, and is currently being used in an industry consortium to develop a dent criticality criteria that can be applied to dents found in-service (in-line inspection) or during excavation programs. Phase I of this project was completed in May 2002 and Phase II will commence in Fall 2002. Part of the Phase II project scope will consider the impact of localized effects including gouging and weld seams.
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Project Summary
-3) Proposed Research Action Plan (How will the problem be solved):
In order to develop an assessment model, several areas of investigation will be required:
Year 1 - Task 1 - Assessment of Pipe Deformation on the Integrity of the Pipeline This work was developed in Phase I of the industry consortium project at BMT FTL and will be further developed in Phase II. The dent ranking criteria developed in the Phase I project was a function of pipe and dent geometry and pipeline operating conditions and was used to develop a relative ranking of the severity of a list of dents.
The Phase II work will carry this forward to assign residual lives to a dented pipe segment.
Year 1 - Task 2 - Modeling the Impact of Line Strike Material Damage This phase of the project will first require a review of all available literature to determine the extent of the past projects related to characterizing the severity and failure modes for mechanical damage. This work is scheduled as part of the Phase II industry consortium project and can be carried further in conjunction with the funding proposed by PRCI. The next stage of this work will involve numerical modeling of mechanical damage in pipelines to obtain a calibrated model to predict the
morphology of mechanical damage features and their effects on localized stress distributions. The LS Dyna finite element analysis package is well suited for modeling impact, contact and material cold working and will be used in this phase of the
analysis process. The conclusions will be added to the dent characterization criteria to expand the methodology beyond smooth dents to dents with associated material damage.
Year 1 - Task 3 - Consideration of Other Localized Effects
The dent characterization model will be further modified to account for the impact of additional features which may be associated with mechanical damage (metal loss, cracking, weld seams) and can further impact the integrity of the pipeline. Numerical modeling will be validated using the published results from full-scale trials.
Year 2 - Task 4 - Further Model Validation and Implementation.
As a further measure of the validity of the model, the funding made available in Year 2 will be used to conduct further testing to ensure that all appropriate information is available when validating the model. Any shortcomings in available published data will be identified during Year 1.
Project Summary
Committee: Pipeline Materials
Project Title:
Mechanical Damage Direct Assessment - RPTG-0321
-4) Expected Deliverables (List Specifically what PRCI will get out of the work):
A validated and robust methodology for characterizing the impact of mechanical damage on the integrity of a pipeline. The methodology will be developed using numerical modeling, but will be adapted so that it can be applied without the need for detailed numerical analysis.
A set of guidelines with examples of how the methodology can be applied to various forms of data, whether it was collected using in-line inspection tools or during field excavation.
A report documenting the results of the modeling processes.
5) Resource Requirements (total cost, year-by-year breakdown, capital costs vs.
overhead, and outside resources to be used):
It is anticipated that the total expenditures required to complete this work will be in the order of $460,000 USD and will be broken down as follows:
In-kind contributions:
• $100,000: Initial development of the BMT FTL Dent Assessment Model
• $100,000: Phase I work of the dent characterization consortium project
• $60,000: Contribution of the Phase II work from the dent characterization consortium project supported by the consortium members
• $50,000: Licensing fees for FEA modeling packages covered by BMT FTL.
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Project Summary
-6) Organization Information (Describe major business of contractor, facilities available for use in this project, related concurrent/recent projects):
BMT FTL provides engineering research and services to the pipeline industry in the welding, materials characterization, and damage tolerance (ECA) areas of interest. Research efforts at BMT FTL have resulted in the development of dent and buckle/wrinkle assessment models. These tools support the integrity assessment of mechanically damaged pipes segments. Beyond the assessment of dents and wrinkles, the metallurgical, mechanical testing, welding and numerical simulation labs at BMT FTL have been involved in the following related projects:
• Development of a hot tap tee design model
• Development and calibration of pipeline pressure retaining sleeve design models
• Development of fatigue and fracture analysis tools and courses for industry
8) Alternative Funding Sources:
The proposed program will be subsidised and progress facilitated through:
• the use of pre-existing mechanical damage (dent and wrinkle) modeling tools developed under separate contracts,
• the use of previously completed full-scale trial data to validate the numerical modeling tools,
• the use of previously developed pipeline operation characterization techniques and tools
• the use of previously collected and characterised pipeline material and operational data.
Co-operative funding will also be sought from on-going parallel industry group sponsored projects to subsidise the work in this project.
BMT FLEET TECHNOLOGY LIMITED 5561P BMT FTL Document Quality Control Data Sheet
Report: Mechanical Damage Direct Assessment – RPTG-0321 –
Project No. 5561P
Date: 5 August 2002
Prepared by:
L. Blair Carroll, Project Engineer
Reviewed by:
R. B. Lazor, Manager BMT FTL Western Canada Office
Approved by: A. Dinovitzer, Vice-President
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BMT FLEET TECHNOLOGY LIMITED 5561P TABLE OF CONTENTS
Page
1. INTRODUCTION... 1
1.1 Proposal Layout/Administrative Details ...1
1.2 Background and Incentives ...1
1.2.1 Project Objective ...2
2. WORK PLAN... 2
2.1 Overview ...2
2.2 Scope of Work ...2
2.2.1 Task 1 – Literature Review ...2
2.2.2 Task 2 – Formalization of Pipeline Specific Parameters ...2
2.2.3 Task 3 – Formalization of Inspection Information Parameters ...4
2.2.4 Task 4 – Evaluation of Model on Test Sections...4
2.2.5 Task 5 – Final Report...6
2.3 References...6
3. PROJECT TEAM AND QUALIFICATIONS... 7
3.1 Project Team...7
3.2 Related Projects ...8
4. PROJECT MANAGEMENT... 9
4.1 Project Schedule...9
APPENDICES
APPENDIX A: RESUMES
APPENDIX B: CORPORATE CAPABILITIES
vi
BMT FLEET TECHNOLOGY LIMITED 5561P LIST OF FIGURES AND TABLES
Figure 2.1: BMT Fleet Technology Dent Assessment Modeling Process [3]...5
Figure 2.2: Effect of D/t on Remaining Life Estimates for Dented Pipe [2] ...6
Figure 3.1: Proposed Project Team and Additional Available Staff ...8
Figure 4.1: Project Management Control ...10
Figure 4.2: Example of Weekly Project Cost Summary Sheet...11
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BMT FLEET TECHNOLOGY LIMITED 5561P
1. INTRODUCTION
In this section we describe the proposal layout, provide our understanding of the need for the project, its objectives and summarize the technical approach proposed for the project.
1.1 Proposal Layout/Administrative Details
This proposal is prepared in response to PRCI Request for Proposal No. RPTG-0321. It is submitted by BMT Fleet Technology Limited (BMT FTL) of Kanata, Ontario, who will act as the prime contractor.
The proposal is presented in two parts contained in one volume:
• Part I - Technical and Management Proposal, and
• Part II - Price Proposal
The proposal includes a copy of the pre-proposal submitted by BMT FTL as a summary of the following information:
Section Contents
Proposal Summary (PRCI Pre-Proposal) 1 Proposal Introduction and Technical Summary 2 Details of the Technical Approach by Task 3 Project Team Qualifications
4 Project Management Approach 1.2 Background and Incentives
With the increased emphasis placed upon pipeline integrity management programs, new
approaches to detecting and repairing pipeline flaws have been, and continue to be, developed.
Current requirements placed on pipeline operators mandate the inspection of pipeline systems on regular intervals via either pressure testing or in-line inspection. Unfortunately, a large
percentage of pipeline systems are neither equipped to allow the passage of in-line inspection tools, nor can one readily isolate the lines for hydrostatic testing. Furthermore, many pipelines provide single product sources so downtime related to in-line inspections and pressure testing would result in significant disruption for the end user of the product.
In an effort to address these issues, new processes are under development to mitigate corrosion and stress corrosion cracking related degradation process using the concept of ‘Direct
Assessment’. Some of the recent developments include:
• NACE International has implemented working groups to develop recommend practices for Direct Assessment Procedures related to external corrosion (TG-041);
• The draft version of the revised ASME B31.8 contains summary information to address internal corrosion direct assessment approaches;
• Formalized procedures are being developed to address Direct Assessment methodologies to mitigate stress corrosion cracking [1].
Each of the above utilizes databases of information collected on pipeline systems combined with known features of the degradation mechanism to predict the most probable locations the of degradation on a pipeline. After these locations are identified, exploratory excavation programs are planned to assess the current condition of the pipeline and address long-term integrity concerns. The methodologies essentially employ four categories of data:
1. Pipeline specific: material properties, pipe geometry, coating type, operating pressure history, past excavation history, failure history, etc.
2. Inspection information: closed spaced CP surveys, etc.
BMT FLEET TECHNOLOGY LIMITED 5561P
3. Environmental: soil type along right of way, drainage, etc.
4. Degradation mechanism specific
Overlaying the four categories of data in a risk-based approach, models can be developed to highlight the most probable locations of the damage along a pipeline right of way.
The prevention of mechanical damage related failures using direct assessment type methodologies have not been formalized. Unlike corrosion or environmental cracking, the environmental and degradation specific degradation data is not applicable. It is proposed that pipeline specific and inspection information can be used to develop a direct assessment approach to mitigate mechanical damage on a pipeline system.
1.2.1 Project Objective
The work proposed in this document will seek to develop a recommended practice based upon direct assessment concepts to address mechanical damage concerns on a pipeline system that cannot be inspected using applicable ILI technologies or be easily pressure tested. The process will incorporate pipeline specific data, land use information, inspection results and operating history details.
2. WORK PLAN
2.1 Overview
This proposal includes the technical experience and expertise of personnel at BMT Fleet Technology Limited (BMT FTL) in the development of techniques to determine the damage tolerance of, or significance of damage to, pipeline systems. The full-scale evaluation of the range of mechanical damage induced failure modes proposed in this project would be a
monumental task financially, therefore a numerical modeling approach has been proposed. The scope of the model development is limited by previous work completed by the staff at FTL. The six tasks proposed for this work are summarized in Figure 1.9 and the section that follow provide detailed descriptions of the work to be carried out in this project. These tasks include a first year of model refinement and validation followed by their application to develop damage acceptance criteria.
2.2 Scope of Work
2.2.1 Task 1 – Literature Review
An extensive literature summary will be compiled to identify key elements contributing to mechanical damage related failures using several data sources, which include available regulatory agency or operating company failure reports, and sponsor company maintenance excavation histories. This information gathering phase of the project will summarize failure mechanisms associated with mechanical damage, and also to develop statistics related to pipe contact incidents by third parties that had not failed. The focus will be to identify common occurrences associated with the failures that may lead to previously unanticipated elements of a direct assessment procedure. It is proposed that the elements will be subdivided into two primary categories:
• Pipeline Specific Parameters
• Inspection Information Parameters
2.2.2 Task 2 – Formalization of Pipeline Specific Parameters
The pipeline specific parameters identified from Task 1 will be assessed as to their potential use in a direct assessment methodology. It is anticipated that the weighting applied to the different parameters will address both the contribution to the possibility of failure and also their usefulness
Mechanical Damage Direct Assessment 2
BMT FLEET TECHNOLOGY LIMITED 5561P
in a direct assessment approach. It is anticipated that the following pipeline specific parameters will be included in the methodology:
• Pipe material properties: The material properties may impact the potential for mechanical damage related failures. If a pipeline was constructed over a series of several years, different pipe material may have been used to construct different
segments of the pipeline. Older lower toughness pipe would have a higher risk of failure from mechanical damage. Additionally, the consequences of a failure in low toughness pipe could be more severe than in high toughness pipe since resulting fractures could be larger and run for longer distances before arresting.
• Pipe geometry: The pipe D/t ratio influences the risk of a failure on a pipeline. If the diameter and wall thickness changes along a pipeline then certain areas may be more susceptible to failure than others. Larger diameter pipe also is more likely to be struck during excavation because of its greater size.
• Pipe manufacturing process: If pipe from different sources and/or manufacturing practices was used to construct a pipeline, the end result could have similar results on the risk of failure as the material properties since the two are related. If a mix of low frequency ERW pipe and DSAW pipe were used then mechanical damage associated with LFERW welds would have a higher potential for failure because of the low toughness traditionally associated with the fusion line of this welding process.
• Land use: Land use in the vicinity of a pipeline can identify regions with a higher likelihood for the presence of mechanical damage. Pipelines running through farmers’
fields, for instance, have a higher probability of a line strike than a pipeline running through a wilderness area. Pipelines near residential areas would similarly have a higher likelihood and consequence of failure than a pipeline in a remote location. Recent development and changes in class location would be additional factors to consider.
Separate risk and consequence indices would have to be applied.
• Historical Failure Data: Some regions may have experienced a higher number of mechanical damage failures than others. Factors affecting this could be related to work conducted around the pipeline right of way. If for instance several failures occurred in an area where a particular contractor was working and the entire region was not excavated and visually inspected, then there is a potential for additional line strikes in the same region.
• Pipeline Route: Pipelines routed through areas with deep clay soil layers would be less likely to have dents resulting from pipe laying or in-service dents resulting from pipe movement than pipelines routed through regions where the bedrock is nearer to the surface. The soil could also include large boulders, which are known to be associated with pipe deformation.
• Pipeline Operating Pressure History and Pressure Profile: For time dependent failures related to mechanical damage, fatigue crack growth is likely a contributor to the failure process. Operating pressure data from the pipeline system can be analyzed to identify regions with the potential for the highest fatigue crack growth rates.
The pipeline specific parameters could be used to rank the highest risk locations along a pipeline right of way using a pipeline indexing measure, Ip, of the form:
(
RiskParameters)
f(ConsequenceParameters)f
IP= +
The functions applied to the risk and consequence parameters could include weighting features that would be applied to the individual parameter.