HEAVY LIFT INSTALLATION STUDY OF OFFSHORE STRUCTURE 2004

HEAVY LIFT INSTALLATION STUDY
OF
OFFSHORE STRUCTURES
LI LIANG
(MS. Eng, NUS)
A THESIS SUBMITTED
FOR THE DEGREE OF MASTER OF ENGINEERING
DEPARTMENT OF CIVIL ENGINEERING
NATIOANL UNIVERSITY OF SINGAPORE
2004

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HEAVY LIFT INSTALLATION STUDY
OF
OFFSHORE STRUCTURES
LI LIANG
(MS. Eng, NUS)
A THESIS SUBMITTED
FOR THE DEGREE OF MASTER OF ENGINEERING
DEPARTMENT OF CIVIL ENGINEERING
NATIOANL UNIVERSITY OF SINGAPORE

ACKNOWLEDGMENTS
The author would like to express his sincere appreciation to his supervisor Associate
Professor Choo Yoo Sang. The author is deeply indebted to his most valuable guidance,
constructive criticism and kind understanding. Appreciation is extended to Associate
Professor Richard Liew and Dr. Ju Feng for their assistance and encouragement.
In addition, the author would like to thank the National University of Singapore for
offering the opportunity for this research project.
Finally, the author is grateful to his family, the one he loves, and all his friends, whose
encouragement, love and friendship have always been the major motivation for his study.

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TABLE OF CONTENTS
CHAPTER 1 INTRODUCTION ...................................................................................... 1
1.1 Background
1.2 Objectives and Scope of Present Study
1.3 Organisation of Thesis
CHAPTER 2 REVIEW OF LIFTING DESIGN CRITERIA .......................................... 10
2.1 Review of Various Lifting Criteria
2.2 Practical Considerations for Standard Rigging Design
2.2.1 Sling Design Loads (SDL)
2.2.2 Shackle Design Loads
2.2.3 Lift Point Design Loads
2.2.4 Shackle Sizing
2.2.5 Tilt during Lifting
2.2.6 COG Shift Factor
2.3 Summary
CHAPTER 3 HEAVY LIFTING EQUIPMENT AND COMPONENTS....................... 24
3.1 Introduction
3.2 Heavy Lift Cranes
3.2.1 Crane Vessel Types
3.2.2 Frequently Used Crane Vessels
3.3 Heavy Lift Shackles
3.4 Heavy Lift Slings
3.4.1 Sling properties
3.4.2 Grommets versus Slings
3.4.3 Sling and Grommet Properties
3.5 Lift Points
3.6 Summary
CHAPTER 4 RIGGING THEORY AND FORMULATION ......................................... 57
4.1 Introduction
4.2 Rigging Sling System with Four Lift Points
4.2.1 Using Main or Jib Hook without Spreader Structure
4.2.2 Using Main or Jib Hook with Spreader Structure
4.2.3 Using Main and Jib Hooks at the Same Time
4.3 Rigging Sling System with Six Lift Points
4.3.1 Using Main or Jib Hook with Spreader Frame
4.3.2 Using Main and Jib Hooks without Spreader Structure
4.4 Rigging Sling System with Eight Lift Points
4.4.1 Using Main or Jib Hook with/without Spreader Structure
4.4.2 Using Main and Jib Hooks without Spreader Structure
4.5 Summary

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CHAPTER 5 JACKET LIFTING.................................................................................... 78
5.1 Introduction
5.2 Vertical Lift of Jackets
5.3 Horizontal Lift of Jackets
5.4 Summary
CHAPTER 6 MODULE LIFTING.................................................................................. 88
6.1 Introduction
6.2 Vertical Module Lift and Installation
6.3 Deck Panel Flip-Over
6.4 Summary
CHAPTER 7 FPSO STRUCTURE LIFTING ............................................................... 102
7.1 Introduction
7.2 Lift Procedures and Considerations for FPSO Modules
7.3 Rigging Systems with Multiple Spreader Bars
7.4 Lifting of Lower Turret
7.5 Lifting of Gas Recompression Module
7.6 Lifting of Flare Tower
7.7 Summary
CHAPTER 8 SPECIAL LIFTING FRAME DESIGN .................................................. 121
8.1 General Discussion
8.2 Effect of the Shift of the Centre of Gravity
8.3 Lift Point Forces
8.4 Padeye Checking
8.5 Trunnion Checking
8.6 Summary
CHAPTER 9 FINITE ELEMET ANALYSIS FOR LIFTING DESIGN ....................... 139
9.1 Introduction
9.2 Finite Element Analysis for Module Lifts
9.2.1 Structural and Material Details
9.2.2 Finite Element Modelling and Analysis
9.2.3 Discussions
9.3 Finite Element Analysis for Lifting Padeye Connection
9.3.1 Structural Details
9.3.2 Loading Cases
9.3.3 Finite Element Modelling
9.3.4 Result Analysis
9.4 Summary
CHAPTER 10 CONCLUSIONS AND FUTURE WORKS.......................................... 170
10.1 Conclusions
10.2 Recommendation for Future Work
BIOBLIOGRAPHY ....................................................................................................... 174
APPENDIX A FEM ANALYSIS FOR JACKET UPENDING PADEYE .................... 181