Behaviour of Corroded X46 Steel Pipe under Internal Pressure and Axial Load

274 Pages·2015·4.02 MB·English

University of Windsor
Scholarship at UWindsor
Electronic Theses and Dissertations
2009
Behaviour of Corroded X46 Steel Pipe under
Internal Pressure and Axial Load
Halima Dewanbabee
University of Windsor
Follow this and additional works at:http://scholar.uwindsor.ca/etd
Recommended Citation
Dewanbabee, Halima, "Behaviour of Corroded X46 Steel Pipe under Internal Pressure and Axial Load" (2009).Electronic Theses and
Dissertations.Paper 78.
This online database contains the full-text of PhD dissertations and Masters’ theses of University of Windsor students from 1954 forward. These
documents are made available for personal study and research purposes only, in accordance with the Canadian Copyright Act and the Creative
Commons license—CC BY-NC-ND (Attribution, Non-Commercial, No Derivative Works). Under this license, works must always be attributed to the
copyright holder (original author), cannot be used for any commercial purposes, and may not be altered. Any other use would require the permission of
the copyright holder. Students may inquire about withdrawing their dissertation and/or thesis from this database. For additional inquiries, please
contact the repository administrator via email ([email protected]) or by telephone at 519-253-3000ext. 3208.
Behaviour of Corroded X46 Steel Pipe under Internal
Pressure and Axial Load

By

Halima Dewanbabee

A Thesis
Submitted to the Faculty of Graduate Studies
through Civil and Environmental Engineering
in Partial Fulfillment of the Requirements for
the Degree of Master of Applied Science at the
University of Windsor

Windsor, Ontario, Canada
2009

© 2009 Halima Dewanbabee
Behaviour of Corroded X46 Steel Pipe under Internal Pressure and Axial Load

by

Halima Dewanbabee

APPROVED BY:
_____________________________________________
Dr. D. Green, Outside Department Reader
Mechanical, Automotive and Materials Engineering

______________________________________________
Dr. M. K. S. Madugula, Department Reader
Department of Civil and Environmental Engineering

______________________________________________
Dr. S. Das, Principal Advisor
Department of Civil and Environmental Engineering

______________________________________________
Dr. J. B. Kennedy, Co-Advisor
Department of Civil and Environmental Engineering

______________________________________________
Dr. T. Bolisetti, Chair of Defense
Department of Civil and Environmental Engineering

19 June 2009
Author’s Declaration of Originality

I hereby certify that I am the sole author of this thesis and that no part of this thesis has
been published or submitted for publication.

I certify that, to the best of my knowledge, my thesis does not infringe upon anyone’s
copyright nor violate any proprietary rights and that any ideas, techniques, quotations, or
any other material from the work of other people included in my thesis, published or
otherwise, are fully acknowledged in accordance with the standard referencing practices.
Furthermore, to the extent that I have included copyrighted material that surpasses the
bounds of fair dealing within the meaning of the Canada Copyright Act, I certify that I
have obtained a written permission from the copyright owner(s) to include such
material(s) in my thesis and have included copies of such copyright clearances to my
appendix.

I declare that this is a true copy of my thesis, including any final revisions, as approved
by my thesis committee and the Graduate Studies office, and that this thesis has not been
submitted for a higher degree to any other University or Institution.

ii i
Abstract

Corrosion is a major cause for buried gas pipeline failure. Current design guidelines are
limited to pressure loading for assessing corroded pipeline’s integrity. A few studies were
conducted by other researchers to determine the remaining bending or pressure strength
of the corroded pipelines under combined loading. No study was conducted to determine
the axial compressive strength of the corroded pipelines although it could be the major
cause of pipeline failure.
Therefore, the current study was completed using full-scale tests and a parametric study
using FEA to assess the integrity of X46 corroded pipe subjected to severe axial
compression and internal pressure.
Test specimens showed high ductility and never ruptured. The finite element analysis,
however, showed that this pipe may rupture if internal pressure and/or corrosion
dimensions are changed. The parametric study helped to develop a guidelines that the
pipeline operators can use for assessing the safety of their corroded pipelines.
iv
Dedication

To My Children
Maliha and Mehran

v
Acknowledgements

I am deeply indebted to my supervisor Dr. S. Das whose help, stimulating suggestions,
continuous support and encouragement helped me in all the time of this research work
and writing of this thesis. Dr. Das devoted his time and sincere efforts to provide all
necessary research facilities for this work. I am also heartily thankful to my co-advisor
Dr. J. B. Kennedy for his financial support. I would like to express my appreciation to the
committee members: Dr. D. Green and Dr. M. K. S. Madugula for their valuable and
constructive suggestions to improve this thesis work.

I also would like to express my gratitude to all technical staff: Lucian Pop, Patrick
Seguin, and Matthew St. Louis for their assistance in laboratory work.

I must acknowledge the financial assistance and scholarship that I received from the
Department of Civil and Environmental Engineering and the Faculty of Graduate Studies
of the University of Windsor.

v i
Table of Contents

Author’s Declaration of Originality...................................................................................iii
Abstract..............................................................................................................................iv
Dedication...........................................................................................................................v
Acknowledgements............................................................................................................vi
List of Figures..................................................................................................................xiii
List of Tables....................................................................................................................xx
List of Symbols................................................................................................................xxi
1 Introduction......................................................................................................................1
1.1 General......................................................................................................................1
1.2 Statement of Problem................................................................................................2
1.3 Objectives and Scope................................................................................................2
1.4 Organization of the Thesis........................................................................................3
2 Literature Review............................................................................................................5
2.1 General......................................................................................................................5
2. 2 Causes of Pipeline Corrosion...................................................................................5
2.3 Types of Corrosion...................................................................................................7
2.3.1 External Corrosion.............................................................................................8
2.3.2 Internal Corrosion..............................................................................................9
2.4 Classification of Corrosion in Pipeline Industry.......................................................9
2.5 Current Codes and Standards..................................................................................11
vi i
2.5.1 ASME B31G-1991 Equation...........................................................................11
2.5.2 CSA Z662-07 Guideline..................................................................................13
2.5.3 DNV RP-F101 Criterion..................................................................................16
2.6 Studies on load deformation behaviour of corroded pipeline.................................22
2.6.1 Analytical and Experimental Models...............................................................22
2.6.2 Numerical Models............................................................................................29
3 Experimental Program...................................................................................................40
3.1 General....................................................................................................................40
3.2 Selection of Specimen Parameters..........................................................................40
3.3 Selection of Boundary Conditions..........................................................................41
3.4 Selection of Corrosion Shape..................................................................................41
3.5 Selection of Internal Pressure.................................................................................42
3.6 Modelling of Field Conditions................................................................................42
3.6.1 Axial Load Caused by the Thermal Effects.....................................................42
3.6.2 Axial Load Caused by the Landslide...............................................................43
3.6.3 Axial Load Resulting From the Poisson's Ratio Effect for Hoop Stresses......43
3.6.4 Axial Load Caused by Internal Pressure Acting on Closed Ends of Specimens
...................................................................................................................................44
3.6.5 Total Axial Load..............................................................................................45
3.7 Test Variables.........................................................................................................45
3.8 Preparation of the Specimen...................................................................................46
3.9 Detail of the Corrosion............................................................................................46
3.10 Designation of the Specimen................................................................................47
3.11 Material Property..................................................................................................47
3.12 Details of Test Specimen......................................................................................48
3.12.1 Control Specimen...........................................................................................48
3.12.2 Group 1 Specimens........................................................................................48
vi ii
3.12.3 Group 2 Specimens........................................................................................48
3.13 Test Setup..............................................................................................................49
3.14 Instrumentation.....................................................................................................50
3.14.1 Electrical Resistance Strain gauges...............................................................50
3.14.2 LVDT (Linear Voltage Displacement Transducer)......................................51
3.14.3 Rotation Meters..............................................................................................51
3.14.4 Fluid Pump.....................................................................................................51
3.14.5 Data Acquisition System................................................................................51
3.15 Test Procedure......................................................................................................51
4 Experimental Results.....................................................................................................79
4.1 General....................................................................................................................79
4.2 Discussion on behaviour of Group 1A....................................................................80
4.2.1 Load Deformation Behaviour..........................................................................80
4.2.2 Local Strain Behaviour....................................................................................81
4.3 Discussion on behaviour of Group 1B....................................................................82
4.3.1 Load Deformation Behaviour..........................................................................82
4.3.2 Local Strain Behaviour....................................................................................83
4.4 Discussion on behaviour of Group 2A....................................................................83
4.4.1 Load Deformation Behaviour..........................................................................84
4.4.2 Local Strain Behaviour....................................................................................85
4. 5 Discussion on Behaviour of Group 2B..................................................................85
4.5.1 Load Deformation Behaviour..........................................................................85
4.5.2 Local Strain Behaviour....................................................................................86
4.6 Effect of Pressure and Corrosion Dimensions........................................................87
4.6.1 Effect of Internal Pressure...............................................................................87
4.6.2 Effect of Corrosion Depth................................................................................88
4.6.3 Effect of Circumferential Length of Corrosion Defect....................................89
4.7 Summary.................................................................................................................90
ix