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					                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
                                                                                                          Doc. Class :

                                                        Discipline : Error! Unknown Revision : D1
Document type:            System/Subsystem :                                                              Rev. Date :
                                                        document property name.

Contractor Job No : 365                Contract No : 4600006595                                          Page 1 of 17




                                          UJUNG PANGKAH DEVELOPMENT
                                                    OFFSHORE PHASE II

 HESS (INDONESIA-PANGKAH) LTD
                                                         (WHP-B EPCC)




       Strandjack Bracket Design For Jacket and Topside




 D1       22-July-09                Issued For Approval                    DBES          HKM          MARK

  A       18-May-09                  Issued for Review                     DBES          HKM          MARK
                                                                             By         Check          App         By      Date
Rev.          Date                       Description                            Contractor Approval              Company Approval
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
            DESIGN OF JACKET STRAND JACK SUPPORT
                                                                                                          Doc. Class :

                                                        Discipline : Error! Unknown Revision : D1
Document type:            System/Subsystem :                                                              Rev. Date :
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                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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                                               TABLE OF CONTENTS

     CHAPTER                                                                                                      PAGE

     1.0         INTRODUCTION                                                                                     4

     2.0         SCOPE OF WORK                                                                                    4

     3.0         DESIGN SPECIFICATION                                                                             4

     4.0         DESIGN APPROACH                                                                                  5

     5.0         DESIGN OF STRAND JACK SUPPORT                                                                    6

     6.0         MANUAL DESIGN VERIFICATION                                                                       11



     APPENDICES

     APPENDIX – A STRAND JACK SPECIFICATION

     APPENDIX – B WEIGHT CONTROL SUMMARY & ESTIMATION OF REQUIRED PULL
                  FORCE

     APPENDIX – C STRAND JACK SUPPORT DRAWINGS

     APPENDIX – D FEM INPUT & OUTPUT FILES
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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     1.0 INTRODUCTION
     This document presents the analysis and structural design of strand jack support for loading out
     WHP-B Jacket Structure at Bakrie Fabrication Yard. The WHP-B Jacket Structure will be skidded out
     from its fabrication position onto the transportation barge using hydraulic strand jack system. These
     strand jacks will be mounted on the existing skid frame temporary support structures that support the
     entire weight of the WHP-B Jacket Structure.
     For typical strand jack specification and details, refer to Appendix – A.


     2.0 SCOPE OF WORK
     Design checks are limited to global and local strength of the strand jack support and its attachments
     where the strand jack supports are to be mounted and maximum pull forces are supported.
     Detailed skid frame, tie back system and jacket member structural integrity strength checks are
     beyond the scope of this report.


     3.0 DESIGN SPECIFICATION

     (1) API RP 2A 21st Edition – Recommended Practice fo Planning, Designing and Constructing
         Fixed Offshore Platforms (WSD) by American Petroleum Institute
     (2) AISC Manual of Steel Construction (Allowable Stress Design) – by American Institute of Steel
         Construction

     Generally, increases in basic allowable stresses ARE NOT allowed for load out condition.

     The following basic and combined allowable stressed criteria are adopted (Fy is material yield
     strength):

     Axial Tension, Fat                = 0.60Fy
     Axial Compression, Fac            = Max 0.60Fy
     Bending Stress, Fby               = 0.66Fy
     Shear Stress, Fv                  = 0.40Fy
     Von Mises Stress, Fvm             = 0.80Fy for combined axial, bending and shear stresses
                                                                                      Doc. No :

                                                                                                      UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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Contractor Job No : 365                  Contract No : 4600006595                                          Page 5 of 17



     4.0 DESIGN APPROACH


     (a) Strand Jack Support Arrangement
     The Strand Jack Support System are to be arranged in such the manner that the induced forces due to
     skidding operation will be adequately transferred to the existing temporary support structures and skid
     frame system.


     (b) Design Loadings / Assumptions
     The following design loadings are considered:
                 Weight Control Report No:            UPD-BC-W2-WC-RP-0002, Rev 3
                 Factored Weight                       = 403.7MT
                 Assumed vertical static load on support can = 73MT per leg
                 Assumed coefficient of friction = 20% during initial skidding stage,
                 Nos of Strand jack, N                  = 2 Nos
                 Estimated pull force per jack         = 43.4MT / jack
                 (Refer to Appendix – B for Weight Control Summary & Estimation of Required Pull
                 Capacity)


     (c) Analysis and Design Methodology
     Analysis and design are performed using SAP2000 Finite Element Software (FEM) and verified by
     manual calculation.


     (d) Materials
     All plate materials shall be of ASTM 36 (Min. Yield Strength = 248MPa) or equivalent, unless
     specified otherwise. All welding shall comply with AWS1.1 and shall be of full penetration welds,
     unless specified otherwise.
                                                                                                     Doc. No :

                                                                                                                      UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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Contractor Job No : 365                           Contract No : 4600006595                                                       Page 6 of 17




     5.0 DESIGN OF STRAND JACK SUPPORT


     5.1 GENERAL ARRANGEMENT
     The Strand Jack Support System are to be arranged in such the manner that the induced forces due to
     skidding operation will be adequately transferred to the existing temporary support structures and skid
     frame system. It shall be ensured that the all the strands are clash-free with jacket or other temporary
     structures. For detail strand jack support drawings, refer to Appendix – C.


     SAP2000 Ver.10 software is used for structural modelling and analysis of the strand jack support
     system. The temporary support can and strand jack supports are modelled as finite element (shell
     element) with appropriate restraint conditions (fixed-supported).


     The following presents the isometric view of the simplified structural model of strand jack support
     system:



                                             Temporary Support Can Dia1181x32thk




                 Strand Jack Support (Typ)        Top FLG/Ring Plate PL25




                                                                                                      Exist'g Bottom FLG/Ring PL25
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                                                                                                       UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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     5.2 ELEMENT PROPERTIES
     The following table summarizes the element and material properties assumed in the analysis:

                                                                                                                                Material
                                                                                                       Shell Thk
          S/N      Description                               Element Type           Shell Grp                            Yield Strength
                                                                                                           [mm]                  [Mpa]
           1       Strand Jack Support                               Shell            PL25                  25                    248
           2       Support Can Dia1181mm                             Shell            PL32                  32                    248
           3       Exist'g Bottom Flange Plate                       Shell            PL25                  25                    248
           4       Additional Top Flange/Stiff Plate                 Shell            PL25                  25                    248



     5.3 LOAD COMBINATION
     The following table summarizes all the basic load cases, associated load factors and combined load
     condition:

                                                            Load             Combined Load Condition
      Basic Load Case
                                                            Case                1000                   -
      Jacket Weight = 73MT* per leg                         STA1                1.00
      Stand Jack Pull Force = 44MT per leg                  PUL2                1.00
      Note *Assumed max static vertical load on each leg for design purpose only.
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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Contractor Job No : 365                Contract No : 4600006595                                          Page 8 of 17




     5.4 ANALYSIS RESULT
     The following presents the Finite Element Model Analysis results – Max Von Mises Stresses
     (Combined Axial, bending, and shear stresses) of the proposed strand jack design:


     (a) Von Mises Stress – Overall




     (b) Von Mises Stress – Support Can (32mm thk Pipe Wall)
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           DESIGN OF JACKET STRAND JACK SUPPORT
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     (c) Von Mises Stress – Strand Jack Support Bottom Flange / Skid Frame Top Flange Plate




     (d) Von Mises Stress – Strand Jack Support Top Flange Plate (with additional flange plate)
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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Contractor Job No : 365                Contract No : 4600006595                                          Page 10 of 17



     Findings
     Generally, the overall stress level (Von Mises Stress) is less than 105MPa.
     High stress zones (i.e. 186MPa) are limited to areas such as the strand jack bearing surface, mainly
     attributed to modelling technique using point load at strand jack supporting joint locations.
     Stress levels on Temporary Support Can are also less than 90MPa (at interface between strand jack
     support and support can).
     For detailed FEM Input & Output Files, refer to Appendix – D.


     Summary
     Conservatively, max Von Mises Stress is found to be 186.7MPa, which is within the allowable stress
     (0.80Fy = 0.80 x 248 = 198MPa) as specified in Section 3.0.
     Therefore, the strand jack design appears to be structurally fit.
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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     6.0 MANUAL DESIGN VERIFICATION
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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Contractor Job No : 365                Contract No : 4600006595                                          Page 12 of 17
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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                                                                                    Doc. No :

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           DESIGN OF JACKET STRAND JACK SUPPORT
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                                                  APPENDIX – A

                              STRAND JACK SPECIFICATION
                                                                                      Doc. No :

                                                                                                      UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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                                                    APPENDIX – B

                              WEIGHT CONTROL SUMMARY
                                         AND
                          ESTIMATION OF REQUIRED PULL FORCE
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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                                                  APPENDIX – C

                          STRAND JACK SUPPORT DRAWINGS
                                                                                    Doc. No :

                                                                                                    UPD-BC-G4-CS-DR-6003
           DESIGN OF JACKET STRAND JACK SUPPORT
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                                                  APPENDIX – D

                                  FEM INPUT & OUTPUT FILE

				
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