0
Research Papers: Offshore Technology

Integrity Assessment of Offshore Subsea Wells: Evaluation of Wellhead Finite Element Model Against Monitoring Data Using Different Soil Models

[+] Author and Article Information
Massimiliano Russo

Mem. ASME
Statoil ASA,
2103 Citywest Boulevard,
Houston, TX 77042
e-mail: masr@statoil.com

Arash Zakeri

Mem. ASME
BP America Inc.,
501 WestLake Park Boulevard,
Houston, TX 77079
e-mail: arash.zakeri@bp.com

Sergey Kuzmichev

Statoil ASA,
Martin Linges vei 33,
Fornebu 1364, Norway
e-mail: skuzm@statoil.com

Guttorm Grytøyr

Statoil ASA,
Martin Linges vei 33,
Fornebu 1364, Norway
e-mail: gugry@statoil.com

Edward Clukey

BP America Inc.,
501 WestLake Park Boulevard,
Houston, TX 77079
e-mail: edward.cluckey@bp.com

Elizbar B. Kebadze

BP Exploration Operating Co. Ltd.,
Chertsey Road,
Sunbury, London TW16 7LN, UK
e-mail: buba.kebadze@uk.bp.com

Contributed by the Ocean, Offshore, and Arctic Engineering Division of ASME for publication in the JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING. Manuscript received November 6, 2015; final manuscript received June 20, 2016; published online July 29, 2016. Assoc. Editor: Colin Chun Fai Leung.

J. Offshore Mech. Arct. Eng 138(6), 061301 (Jul 29, 2016) (11 pages) Paper No: OMAE-15-1115; doi: 10.1115/1.4034099 History: Received November 06, 2015; Revised June 20, 2016

Understanding well conductor–soil interaction mechanism plays an important role in well integrity assessment. Evaluation of field data obtained from monitored offshore wells can provide valuable insights into the matter. This paper presents a comparison of the numerical results obtained from a full three-dimensional (3D) finite element (FE) analyses model of the blowout preventer (BOP), wellhead (WH), conductor, and surface casing versus the field measured data obtained during drilling operations. Sensitivity studies were also performed for several parameters that were considered important in the local well response analysis under observed sea state conditions. The conductor–soil analyses were simulated using the Winkler spring p–y curves obtained by two different approaches: American Petroleum Institute (API) RP2GEO and a recently developed model by Zakeri et al. The results of bending moments in conductor and surface casing have indicated good agreement between FE model results and the field measurements.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Myhre, E. , Eilertsen, L. E. , Russo, M. , Johansen, F. , Hart, C. , and Kalhovd, T. J. , 2015, “ Successful Real Time Instrumentation of the Conductor and Surface Casing of an Exploration Subsea Well in the North Sea to Measure the Actual Loads Experienced During Drilling Operations,” Offshore Technology Conference, Houston, TX, May, 4–7, Paper No. OTC-25770-MS.
Russo, M. , Myhre, E. , Wolak, U. , and Grytøyr, G. , 2015, “ Measured Wellhead Loads During Drilling Operations: Paper 1—Data Processing and Preliminary Results,” ASME Paper No. OMAE2015-41445.
API, 2011, “ API Recommended Practice 2GEO/ISO 19901-4,” Geotechnical and Foundation Design Considerations, 1st ed., American Petroleum Institute, Washington, DC.
Matlock, H. , 1970, “ Correlations for Design of Laterally Loaded Piles in Soft Clay,” Offshore Technology Conference, Houston, TX, Apr. 22–24, pp. 577–594.
Zakeri, A. , Clukey, E. , Kebadaze, B. , Jeanjean, P. , Walker, D. , Piercey, G. , Templeton, J. , Connelly, L. , and Aubeny, C. , 2015, “Recent Advances in Soil Response Modeling for Well Conductor Fatigue Analysis and Development of New Approaches,” Offshore Technology Conference, Houston, TX, May, 4–7, Paper No. OTC-25795-MS.
Zakeri, A. , Clukey, E. C. , Kebadze, B. E. , and Jeanjean, P. , 2016, “ Fatigue Analysis of Offshore Well Conductors—Part I: Study Overview and Evaluation of Series 1 Centrifuge Tests in Normally Consolidated to Lightly Over-Consolidated Kaolin Clay,” Appl. Ocean Res., 57, pp. 78–95. [CrossRef]
Zakeri, A. , Clukey, E. C. , Kebadze, B. E. , and Jeanjean, P. , 2016, “ Fatigue Analysis of Offshore Well Conductors—Part II: Development New Approaches for Conductor Fatigue Analysis in Clays and Sands,” Appl. Ocean Res., 57, pp. 96–113. [CrossRef]
Jeanjean, P ., 2009, “ Re-Assessment of P-Y Curves for Soft Clays From Centrifuge Testing and Finite Element Modeling,” Offshore Technology Conference, Houston, TX, May 4–7, Paper No. 20158.
Authen, K. , and Grytøyr, G. , 2015, “ Reliable, Low Footprint and Cost-Effective Monitoring of Wellhead Loads Using Autonomous IMUs For Fatigue Estimates,” ASME Paper No. OMAE2015-41882.
Grytøyr, G. , Coral, F. , Lindstad, H. B. , and Russo, M. , “ Wellhead Fatigue Damage Based on Indirect Measurements,” ASME Paper No. OMAE2015-41379.
Buitrago, H. , Krishnan, V. , and Sommerfield, P. M. , 2011, “ Fatigue Assessment of Subsea Tree Connectors and Wellheads,” ASME Paper No. OMAE2011-49853.
Reinås, L. , Hørte, F. , Sæther, M. , and Grytøyr, G. , 2011, “ Wellhead Fatigue Analysis Method,” ASME Paper No. OMAE2011-50026.
Holden, H. , Bjønnes, P. , and Russo, M. , 2013, “ A Simplified Methodology for Comparing Fatigue Loading on Subsea Wellheads,” ASME Paper No. OMAE2013-11529.
Sparks, C. P. , 2007, Fundamentals of Marine Riser Mechanics: Basic Principles and Simplified Analyses, PennWell, Tulsa, OK.
ISO, 2005, “ Design and Operation of Subsea Production Systems—Part 7: Completion/Workover Riser Systems,” International Organization for Standardization, Geneva, Switzerland, Standard No. ISO 13628-7.
Abaqus, 2013, “ Abaqus 6.13,” Dassault Systèmes Simulia Corp., Waltham, MA.

Figures

Grahic Jump Location
Fig. 1

MSU1—motion sensor location below the LFJ

Grahic Jump Location
Fig. 2

Strain gauges locations on conductor casing

Grahic Jump Location
Fig. 3

Strain gauges locations on surface casing

Grahic Jump Location
Fig. 4

Wave conditions considered (weather for events)

Grahic Jump Location
Fig. 6

p–y data—LB soil strength, clay, 6 m depth, only no damping curves used in the paper

Grahic Jump Location
Fig. 7

p–y data—upper bound (UB) soil strength, sand, 2 m depth

Grahic Jump Location
Fig. 8

Damping ratio and dashpot coefficients used with Zakeri et al. [5] fatigue p–y model for LB soil model

Grahic Jump Location
Fig. 9

FE model description and BC (soil spring elevations taken from the seabed surface in meters are: 0.0, 1.0, 2.0, 3.76, 5.96, 7.96, 10.50, 13.60, 16.90, 20.70, 25.10, 30.10, 35.80, 42.40, and 50.0)

Grahic Jump Location
Fig. 10

Comparison between stress field in detailed and simplified rigid lock models, with resulting load sharing of sectional bending moment

Grahic Jump Location
Fig. 11

Comparison of full 3D model and beam/solid hybrid model for conductor and surface casing section bending moment

Grahic Jump Location
Fig. 12

Simplified beam system

Grahic Jump Location
Fig. 13

Simplified beam system—shear force at section C

Grahic Jump Location
Fig. 14

Simplified beam system—end riser shear force correction factor

Grahic Jump Location
Fig. 15

Indirect procedure—definitions

Grahic Jump Location
Fig. 16

Elevations of the sections for bending moment extraction in FE model

Grahic Jump Location
Fig. 17

Conductor section bending moment around X axis, event 5

Grahic Jump Location
Fig. 18

Surface casing section bending moment around X axis, event 5

Grahic Jump Location
Fig. 19

Conductor section bending moment distribution along vertical elevation below mud line

Grahic Jump Location
Fig. 20

Conductor section bending moment around Y axis for section at 6 m below mud line

Grahic Jump Location
Fig. 21

Rotations at BOP measured location around X axis, event 5

Grahic Jump Location
Fig. 22

Probability distribution of mud line conductor displacements versus mud line soil spring for different soil models, event 4

Grahic Jump Location
Fig. 23

Probability distribution of mud line conductor displacements versus mud line soil spring for different soil models, event 5

Grahic Jump Location
Fig. 24

Probability distribution of mud line conductor displacements versus mud line soil spring for different soil models, event 6

Grahic Jump Location
Fig. 25

Rotations at BOP measured location around X axis, event 4

Grahic Jump Location
Fig. 26

Rotations at BOP measured location around X axis, event 6

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In