Preface xix Acknowledgment xxi About the Author xxiii Part 1: Local Analysis 1 1 Introduction 3 1.1 Flexible Pipelines Overview 3 1.2 Environmental Conditions 4 1.3 Flexible Pipeline Geometry 7 1.4 Base Case-Failure Modes and Design Criteria 9 1.5 Reinforcements 10 1.6 Project and Objectives 12 References 12 2 Structural Design of Flexible Pipes in Different Water Depth 15 2.1 Introduction 15 2.2 Theoretical Models 15 2.3 Comparison and Discussion 24 2.4 Conclusions 34 References 34 3 Structural Design of High Pressure Flexible Pipes of Different Internal Diameter 35 3.1 Introduction References 35 3.2 Analytical Models 37 3.2.1 Cylindrical Layers 37 3.2.2 Helix Layers 39 3.2.3 The Stiffness Matrix of Pipe as a Whole Helix Layers 40 3.2.4 Blasting Failure Criterion 41 3.3 FEA Modeling Description 42 3.4 Result and Discussion 46 3.5 Design 50 3.6 Conclusions 54 References 55 4 Tensile Behavior of Flexible Pipes 57 4.1 Introduction 57 4.2 Theoretical Models 58 4.2.1 Mechanical Model of Pressure Armor Layer 58 4.2.2 Mechanical Behavior of Tensile Armor Layer 61 4.2.3 Overall Mechanical Behavior 63 4.3 Numerical Model 64 4.3.1 Pressure Armor Stiffness 64 4.3.2 Full Pipe 69 4.4 Comparison and Discussion 71 4.5 Parametric Study 77 4.6 Conclusions 79 References 80 5 Design Case Study for Deep Water Risers 83 5.1 Abstract 83 5.2 Introduction 83 5.3 Cross-Sectional Design 85 5.4 Case Study 87 5.5 Design Result 94 5.6 Finite Elements Analysis 97 5.7 Conclusion 100 References 101 6 Unbonded Flexible Pipe Under Bending 103 6.1 Introduction 103 6.2 Helical Layer Within No-Slip Range 104 6.2.1 Geometry of Helical Layer 104 6.2.2 Bending Stiffness of Helical Layer 108 6.3 Helical Layer Within Slip Range 109 6.3.1 Critical Curvature 109 6.3.2 Axial Force in Helical Wire Within Slip Range 111 6.3.3 Axial Force in Helical Wire Within No-Slip Range 112 6.3.4 Bending Stiffness of Helical Layer 114 References 116 7 Coiling of Flexible Pipes 117 7.1 Introduction 117 7.2 Local Analysis 120 7.2.1 Dimensions and Material Characteristics 120 7.2.2 Tension Test 120 7.2.3 Bending Test 123 7.2.4 Summary 124 7.3 Global Analysis 126 7.3.1 Modeling 126 7.3.2 Interaction and Mesh 127 7.3.3 Load and Boundary Conditions 128 7.3.4 Discussion of the Results 128 7.4 Parametric Study 134 7.4.1 Diameter of the Coiling Drum 134 7.4.2 Sinking Distance of the Coiling Drum 135 7.4.3 Reeling Length 138 7.4.4 The Location of the Bearing Plate 139 7.5 Conclusions 142 References 143 Part 2: Riser Engineering 145 8 Flexible Risers and Flowlines 147 8.1 Introduction 147 8.2 Flexible Pipe Cross-Section 147 8.2.1 Carcass 149 8.2.2 Internal Polymer Sheath 150 8.2.3 Pressure Armor 150 8.2.4 Tensile Armor 151 8.2.5 External Polymer Sheath 151 8.2.6 Other Layers and Configurations 152 8.3 End Fitting and Annulus Venting Design 152 8.3.1 End Fitting Design and Top Stiffener (or Bellmouth) 152 8.3.2 Annulus Venting System 153 8.4 Flexible Riser Design 154 8.4.1 Design Analysis 154 8.4.2 Riser System Interface Design 155 8.4.3 Current Design Limitations 156 References 158 9 Lazy-Wave Static Analysis 159 9.1 Introduction 159 9.2 Fundamental Assumptions 162 9.3 Configuration Calculation 162 9.3.1 Cable Segment 163 9.3.1.1 Hang-Off Section 163 9.3.1.2 Buoyancy Section 166 9.3.1.3 Decline Section 166 9.3.2 Boundary-Layer Segment 167 9.3.3 Touchdown Segment 168 9.3.4 Boundary Conditions 170 9.4 Numerical Solution 171 9.5 Finite Element Model 174 9.5.1 Environment 175 9.5.2 Riser 175 9.5.3 Boundary Conditions 175 9.6 Comparison and Discussion 175 9.7 Parameter Analysis 180 9.7.1 Effect of Seabed Stiffness 180 9.7.2 Effect of Hang-Off Inclination Angle 182 9.7.3 Effect of Buoyancy Section Length 185 9.8 Conclusions 187 References 188 10 Steep-Wave Static Configuration 189 10.1 Introduction 189 10.2 Configuration Calculation 190 10.2.1 Touch-Down Segment 191 10.2.2 Buoyancy Segment 194 10.2.3 Hang-Off Segment 195 10.2.4 Boundary Conditions 195 10.3 Numerical Solution 196 10.4 Comparison and Discussion 198 10.5 Parametric Analysis 203 10.5.1 Effect of Buoyancy Segment’s Equivalent Outer Diameter 203 10.5.2 Effect of Buoyancy Segment Length 205 10.5.3 Effect of Buoyancy Segment Location 207 10.5.4 Effect of Current Velocity 209 10.6 Conclusions 212 References 212 Contents ix 11 3D Rod Theory for Static and Dynamic Analysis 213 11.1 Introduction 213 11.2 Nomenclature 215 11.3 Mathematical Model 216 11.3.1 Governing Equations 216 11.3.2 Bending Hysteretic Behavior 220 11.3.3 Bend Stiffener Constraint 222 11.3.4 Pipe-Soil Interaction 224 11.4 Case Study 225 11.5 Results and Discussion 227 11.5.1 Static Analysis 227 11.5.2 Dynamic Analysis 231 11.5.2.1 Top-End Region 231 11.5.2.2 Touchdown Zone 233 11.5.3 Effect of Bend Stiffener Constraint 236 11.5.4 Effect of Bending Hysteretic Behavior 238 11.5.5 Effect of Top Angle Constraint 240 11.6 Conclusions 242 References 243 12 Dynamic Analysis of the Cable-Body of the Deep Underwater Towed System 247 12.1 Introduction 247 12.2 Establishment of Towed System Dynamic Model 248 12.3 Numerical Simulation and Analysis of Calculation Results 251 12.3.1 The Effect of Different Turning Radius 252 12.3.2 The Effect of Different Turning Speeds 253 12.3.3 Dynamic Analysis of the Towed System with the Change of the Parameters of the Cable 254 12.3.4 The Effect of the Diameters of the Towed Cable 257 12.3.5 The Effect of the Drag Coefficients of the Towed Cable 257 12.3.6 The Effect of the Added Mass Coefficient of the Towed Cable 261 12.4 Conclusions 263 Acknowledgments 264 References 264 13 Dynamic Analysis of Umbilical Cable Under Interference 267 13.1 Introduction 267 13.2 Dynamic Model of Umbilical Cable 269 13.2.1 Establishment of Mathematical Model 269 13.2.2 The Discrete Numerical Method for Solving the Lumped Mass Method 271 13.2.3 Calculation of the Clashing Force of Umbilical Cable 277 13.3 The Establishment of Dynamic Simulation Model in OrcaFlex 279 13.3.1 The Equivalent Calculation of the Stiffness of the Umbilical Cable 279 13.3.2 RAO of the Platform 281 13.3.3 The Choice of Wave Theory 281 13.3.4 Establishment of Model in OrcaFlex 282 13.4 The Calculation Results 283 13.4.1 The Clashing Force of Interference 283 13.4.2 The Variation of the Effective Tension Under Interference 285 13.4.3 The Variation of Bending Under Interference 287 13.5 Conclusion 291 References 294 14 Fatigue Analysis of Flexible Riser 295 14.1 Introduction 295 14.2 Fatigue Failure Mode of Flexible Riser 296 14.3 Global Model of Flexible Risers 297 14.3.1 Pipe Element 297 14.3.2 Bending Stiffener 298 14.3.3 Sea Condition 299 14.3.4 Platform Motion Response 300 14.3.5 Time Domain Simulation Analysis 301 14.4 Failure Mode and Design Criteria 302 14.4.1 Axisymmetric Load Model 302 14.4.2 Bending Load Model 303 14.5 Calculation Method of Fatigue Life of Flexible Riser 305 14.5.1 Rainflow Counting Method 305 14.5.2 S-N Curve 305 14.5.3 Miner’s Linear Cumulative Damage Theory 307 14.5.4 Modification of Average Stress on Fatigue Damage 308 14.6 Example of Fatigue Life Analysis of Flexible Riser 309 References 314 15 Steel Tube Umbilical and Control Systems 317 15.1 Introduction 317 15.1.1 General 317 15.1.2 Feasibility Study 318 15.1.3 Detailed Design and Installation 319 15.1.4 Qualification Tests 320 15.2 Control Systems 320 15.2.1 General 320 15.2.2 Control Systems 321 15.2.3 Elements of Control System 322 15.2.4 Umbilical Technological Challenges and Solutions 323 15.3 Cross-Sectional Design of the Umbilical 326 15.4 Steel Tube Design Capacity Verification 327 15.4.1 Pressure Containment 328 15.4.2 Allowable Bending Radius 328 15.5 Extreme Wave Analysis 329 15.6 Manufacturing Fatigue Analysis 330 15.6.1 Accumulated Plastic Strain 330 15.6.2 Low Cycle Fatigue 331 15.7 In-Place Fatigue Analysis 331 15.7.1 Selection of Sea State Data From Wave Scatter Diagram 332 15.7.2 Analysis of Finite Element Static Model 332 15.8 Installation Analysis 332 15.9 Required On-Seabed Length for Stability 333 References 334 16 Stress and Fatigue of Umbilicals 337 16.1 Introduction 337 16.2 STU Fatigue Models 338 16.2.1 Simplified Model 339 16.2.1.1 Axial and Bending Stresses 339 16.2.1.2 Friction Stress 340 16.2.1.3 Simplified Approach: Combining Stresses 342 16.2.1.4 Simplified (Combining Stresses) Fatigue Damage 342 16.2.1.5 Simplified Model Assumptions 343 16.2.2 Enhanced Non-Linear Time Domain Fatigue Model 343 16.2.2.1 Friction Stresses 344 16.2.2.2 Effect of Multiple Tube Layers 344 16.2.2.3 Combined Friction Stresses 345 16.2.2.4 Axial and Bending Stresses 345 16.2.2.5 Combining Stresses 346 16.2.2.6 Fatigue Life 346 16.2.2.7 Benefits of Enhanced Non-Linear Time Domain Fatigue Model 347 16.3 Worked Example 348 16.3.1 Time Domain vs. Simplified Approaches 350 16.3.2 Effect of Friction on STU Fatigue 351 16.3.2.1 Influence of High Tube Friction on Umbilical Fatigue 352 16.3.2.2 Influence of Low Tube Friction on Umbilical Fatigue 352 16.3.2.3 Influence of Metal-to-Metal Friction vs. Metal-to-Plastic Contact on Umbilical Fatigue 352 16.3.3 Effect of Increasing Water Depth 353 16.3.4 Effect of Increasing the Tube Layer Radius 354 16.4 Conclusions 355 16.5 Recommendations 356 References 357 17 Cross-Sectional Stiffness for Umbilicals 359 17.1 Introduction 359 17.2 Theoretical Model of Umbilicals 361 17.3 Bending Stiffness of Umbilicals 362 17.4 Tensile Stiffness of Umbilicals 366 17.5 Torsional Stiffness of Umbilicals 368 17.6 Ultimate Capacity of Umbilicals 368 17.6.1 Minimum Bending Curvature 368 17.6.2 Minimum Tensile Load 369 17.6.3 Tensile Capacity Curve 369 References 372 18 Umbilical Cross-Section Design 375 18.1 Introduction 375 18.1.1 General 375 18.1.2 Sectional Composition of the Umbilical Cable 375 18.1.3 Umbilical Cable Structure Features 376 18.2 Umbilicals Cross-Section Design Overview 377 18.2.1 Umbilical Cross-Section Design Flowchart 377 18.2.2 Load Analysis 378 18.3 Umbilical Cable Cross-Section Design 380 18.3.1 Umbilical Cable Cross-Section Layout Design 380 18.3.2 Tensile Performance Design 381 18.3.3 Bending Performance Design 382 References 384 Part 3: Fiber Glass Reinforced Deep Water Risers 385 19 Collapse Strength of Fiber Glass Reinforced Riser 387 19.1 Introduction 387 19.2 External Pressure Test 388 19.2.1 Testing Specimen 388 19.2.2 Testing System 389 19.2.3 Testing Results 389 19.3 Theoretical Analysis 390 19.3.1 Fundamental Assumptions 390 19.3.2 Constitutive Model of Materials 391 19.3.3 Establish the Equations of Motion 393 19.3.4 Establish Virtual Work Equations 394 19.4 Numerical Analysis 394 19.5 Finite Element Analysis 395 19.5.1 Establish the Finite Element Model 396 19.5.2 The Results of the Finite Element Analysis 397 19.6 Conclusion 401 References 402 20 Burst Strength of Fiber Glass Reinforced Riser 405 20.1 Introduction 405 20.2 Experiment 406 20.2.1 Dimensions and Material Properties of FGRFP 406 20.2.2 Experiment Device 407 20.2.3 Experiment Results 407 20.3 Numerical Simulations 407 20.3.1 Mesh and Interaction 407 20.3.2 Load and Boundary Conditions 408 20.3.3 Numerical Results 409 20.4 Analytical Solution 409 20.4.1 Basic Assumptions 409 20.4.2 Stress Analysis 411 20.4.3 Boundary Condition 414 20.5 Results and Discussion 416 20.6 Parametric Analysis 417 20.6.1 Winding Angle of Fiber Glass 417 20.6.2 Diameter-Thickness Ratio 418 20.7 Conclusions 419 References 419 21 Structural Analysis of Fiberglass Reinforced Bonded Flexible Pipe Subjected to Tension 421 21.1 Introduction 421 21.2 Experiment 423 21.2.1 Basic Assumptions 423 21.2.2 Material Characteristics 425 21.2.3 Experimental Results 426 21.3 Theoretical Solution 427 21.3.1 Basic Assumptions 429 21.3.2 Cross-Section Simplification 429 21.3.3 Fiber Deformation 430 21.3.4 Cross-Section Deformation 431 21.3.5 Equilibrium Equations 434 21.4 Finite Element Model 434 21.5 Comparison and Discussion 436 21.5.1 Tension-Extension Relation 436 21.5.2 Cross-Section Deformation 437 21.5.3 Fiberglass Stress 439 21.5.4 Contribution of Each Material 439 21.5.5 Summary 440 21.6 Parametric Study 442 21.6.1 Winding Angle 442 21.6.2 Fiberglass Amount 443 21.6.3 Diameter-Thickness Ratio 444 21.7 Conclusions 445 Acknowledgement 446 References 446 22 Fiberglass Reinforced Flexible Pipes Under Bending 449 22.1 Introduction 449 22.2 Experiment 451 22.2.1 Experimental Facility 451 22.2.2 Specimen 453 22.2.3 Experiment Process 453 22.2.4 Experimental Results 455 22.3 Analytical Solution 457 22.3.1 Fundamental Assumption 457 22.3.2 Kinematic Equation 457 22.3.3 Material Simplification 459 22.3.4 Constitutive Model 462 22.3.5 Principle of Virtual Work 464 22.3.6 Algorithm of Analytical Solutions 464 22.4 Finite Element Method 465 22.5 Result and Conclusion 466 22.6 Parametric Analysis 469 22.6.1 D/t Ratio 469 22.6.2 Initial Ovality 470 22.7 Conclusions 472 References 473 23 Fiberglass Reinforced Flexible Pipes Under Torsion 475 23.1 Introduction 475 23.2 Experiments 477 23.3 Experimental Results 478 23.4 Analytical Solution 481 23.4.1 Coordinate Systems 481 23.4.2 Elastic Constants of Reinforced Layers (k = 2, 3 … (n − 1)) 483 23.4.3 Reinforced Layers Stiffness Matrix k = 2, 3...(n – 1) 484 23.4.4 Inner Layer and Outer Layer Stiffness Matrix (k = 1, n) 486 23.4.5 Stress and Deformation Analysis 487 23.4.6 Boundary Conditions 491 23.4.7 Interface Conditions 492 23.4.8 Geometric Nonlinearity 493 23.5 Numerical Simulations 494 23.6 Results and Discussions 496 23.7 Parametric Analysis 498 23.7.1 Effect of Winding Angle 498 23.7.2 Effect of Thickness of Reinforced Layers 498 23.8 Conclusions 499 Acknowledgments 500 References 501 24 Cross-Section Design of Fiberglass Reinforced Riser 503 24.1 Introduction 503 24.2 Nomenclature 503 24.3 Basic Structure of Pipe 505 24.3.1 Overall Structure 505 24.3.2 Material 506 24.4 Strength Failure Design Criteria 506 24.4.1 Burst Pressure 506 24.4.2 Burst Pressure Under Internal Pressure Bending Moment 508 24.4.3 Yield Tension 508 24.5 Failure Criteria for Instability Design 510 24.5.1 Minimum Bending Radius 510 24.5.2 External Pressure Instability Pressure 510 24.6 Design Criteria for Leakage Failure 511 References 511 25 Fatigue Life Assessment of Fiberglass Reinforced Flexible Pipes 513 25.1 Introduction 513 25.2 Global Analysis 515 25.3 Rain Flow Method 517 25.4 Local Analysis 519 25.5 Modeling 519 25.6 Result Discussion 520 25.7 Sensitivity Analysis 524 25.8 Fatigue Life Assessment 527 25.9 Conclusion 528 References 529 Part 4: Ancillary Equipments for Flexibles and Umbilicals 531 26 Typical Connector Design for Risers 533 26.1 Introduction 533 26.2 Carcass 534 26.3 Typical Connector 535 26.4 Seal System 536 26.5 Termination of the Carcass 537 26.6 Smooth Bore Pipe 539 26.7 Rough Bore Pipe 540 26.8 Discussion 542 26.9 Conclusions 544 References 545 27 Bend Stiffener and Restrictor Design 547 27.1 Introduction 547 27.2 Response Model 548 27.3 Extreme Load Description 549 27.4 General Optimization Scheme 550 27.5 Application Example 552 27.6 Non-Dimensional Bend Stiffener Design 553 27.7 Alternative Non-Dimensional Parameters 556 27.8 Conclusions 558 References 558 28 End Termination Design for Umbilicals 561 28.1 Introduction 561 28.2 Umbilical Termination Assembly 561 28.2.1 General 561 28.2.2 UTA Design 562 28.2.3 UTA Structural Design Basis 565 28.3 Subsea Termination Interface 566 References 568 29 Mechanical Properties of Glass Fibre Reinforced Pipeline During the Laying Process 569 29.1 Introduction 569 29.2 Theoretical Analysis 570 29.2.1 Wave Load 570 29.2.2 Motion Response of the Vessel 572 29.2.3 Dynamic Numerical Solution 573 29.3 Static Analysis 575 29.4 Dynamic Characteristic Analysis 579 29.4.1 Influence of the Wave Direction 579 29.4.2 Influencing of Different Lay Angle 582 29.4.3 Influencing Submerged Weight 584 29.5 Conclusions 584 References 586 Index 589

This second volume in the Advances in Pipes and Pipelines series focuses on flexible pipelines, risers, and umbilicals, offering the engineer the most up-to-date and comprehensive coverage of pipeline engineering available today. The technology, processes, materials, and theories surrounding pipeline construction, application, and troubleshooting are constantly changing, and this new series, "Advances in Pipes and Pipelines", has been created to meet the needs of engineers and scientists to keep them up to date and informed of all of these advances. This second volume in the series focuses on flexible pipelines, risers, and umbilicals, offering the engineer the most thorough coverage of the state-of-the-art available. The author of this work has written numerous books and papers on these subjects and is one of the most influential authors on flexible pipes in the world, contributing much of the literature on this subject to the industry. This new volume is a presentation of some of the most cutting-edge technological advances in technical publishing. The first volume in this series, published by Wiley-Scrivener, is Flexible Pipes, available at www.wiley.com. Laying the foundation for the series, it is a groundbreaking work, written by some of the world's foremost authorities on pipes and pipelines. Continuing in this series, the editor has compiled the second volume, equally as groundbreaking, expanding the scope to pipelines, risers, and umbilicals. This is the most comprehensive and in-depth series on pipelines, covering not just the various materials and their aspects that make them different, but every process that goes into their installation, operation, and design. This is the future of pipelines, and it is an important breakthrough. A must-have for the veteran engineer and student alike, this volume is an important new advancement in the energy industry, a strong link in the chain of the world's energy production. Deepwater Flexible Risers and Pipelines: Following up on the first volume in the series, introduces a new approach to the design, construction, and installation of flexible pipes, adding risers and umbilicalsPresents both the theory and practical applications of flexible pipes with a view toward its use in pipelines and other industrial settingsDescribes the new materials, technologies, and practical applications of flexible pipelines, risers, and umbilicals, one of the hottest topics in the oil and gas industryIntroduces engineering students to a profound theory for stronger and more efficient designs in pipelines and provides the veteran engineer a valuable reference