Flexible Pipes
Advances in Pipes and Pipelines
1. Edition June 2017
640 Pages, Hardcover
Wiley & Sons Ltd
ISBN:
978-1-119-04126-9
John Wiley & Sons
Further versions
Recent changes in the codes for building pipelines has led to a boom in the production of new materials that can be used in flexible pipes. With the use of polymers, steel, and other new materials and variations on existing materials, the construction and, therefore, the installation and operation of flexible pipes is changing and being improved upon all over the world. The authors of this work have written numerous books and papers on these subjects and are some 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.
This is the most comprehensive and in-depth book on this subject, covering not just the various materials and their aspects that make them different, but every process that goes into their installation, operation, and design. The thirty-six chapters, divided up into four different parts, have had not just the authors of this text but literally dozens of other engineers who are some of the world's leading scientists in this area contribute to the work. 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.
Preface xxi
About the Authors xxiii
Part I Design and Analysis
1 Flexible Pipes and Limit-States Design 3
1.1 I ntroduction 3
1.2 Applications of Flexible Pipe 3
1.2.1 Metal-Based Flexible Pipes 5
1.2.2 Composite-Based Flexible Pipes 7
1.2.3 D esign Codes and Specifications 10
1.3 Comparison between Flexible Pipes and Rigid Pipes 12
1.3.1 Unbonded Flexible Riser vs. Rigid Steel Riser 12
1.3.2 Flexible Jumper vs. Rigid Steel Jumper 12
1.3.3 Flexible Composite Pipe vs. Rigid Pipe 13
1.3.3.1 Material Costs 14
1.3.3.2 I nstallation Costs 14
1.3.3.3 Operational Costs 15
1.3.3.4 Comparison Example 15
1.4 Failure Mode and Design Criteria 15
1.4.1 Unbonded Flexible Pipe 15
1.4.1.1 Failure Modes 15
1.4.1.2 D esign Criteria 17
1.4.2 Flexible Composite Pipe 20
1.4.2.1 Failure Modes 20
1.4.2.2 D esign Criteria 20
1.5 L imit State Design 24
1.5.1 L imit States 24
1.5.2 Reliability-Based Methods 25
References 26
2 Materials and Aging 29
2.1 I ntroduction 29
2.1.1 Unbonded Flexible Pipes 30
2.1.2 Flexible Composite Pipes 34
vi Contents
2.2 Metallic Material 35
2.2.1 Stainless Steel 35
2.2.2 Carbon Steel 36
2.3 Polymer Material 36
2.3.1 Annulus 36
2.3.2 Chemical Resistance 39
2.3.3 Permeation and Permeation Control Systems 41
2.3.3.1 Theory of Gas Permeation 41
2.3.3.2 Permeation Calculation 42
2.3.4 Anti H2S Layer 44
2.4 Aging 45
2.4.1 N onmetallic Material 46
2.4.2 Metallic Material 48
References 49
3 Ancillary Equipment and End Fitting Design 51
3.1 I ntroduction 51
3.1.1 D esign Criteria 51
3.2 Bend Stiffeners and Bellmouths 53
3.2.1 I ntroduction 53
3.2.2 D esign Criteria and Failure Modes 55
3.2.3 D esign Considerations 56
3.2.4 Bellmouths 57
3.3 Bend Restrictor 58
3.4 Buoyancy Modules 59
3.5 Cathodic Protection 60
3.6 Annulus Venting System 61
3.7 E nd Fittings 63
3.7.1 Unbonded Flexible Pipes 64
3.7.1.1 D esign Criteria 64
3.7.1.2 Metallic Materials 66
3.7.1.3 E nd Fittings by Different Manufacturers 66
3.7.2 Flexible Composite Pipes 68
3.7.2.1 D esign Criteria 70
3.7.2.2 Materials 70
3.7.2.3 E nd Fitting Types 71
3.7.2.4 I nstallation 72
References 74
4 Reliability-Based Design Factors 75
4.1 Introduction 75
4.2 Failure Probability 76
4.2.1 L imit State and Failure Mode 76
4.2.2 Failure Probability 76
4.3 Safety Factor Based on Reliability 77
4.3.1 Uncertainties of Resistance and Load Effect 78
4.3.2 L RFD Formulation 79
4.3.3 D esign Process 79
Contents vii
4.4 D esign Example 82
4.4.1 L imit State Function 83
4.4.1.1 Resistance Model for Inner Pressure Load 83
4.4.1.2 L imit State Function 83
4.4.2 Probability Model of Resistance 83
4.4.2.1 Probability Distribution of Resistance Parameters 83
4.4.2.2 Probability Model of Resistance 84
4.4.3 Probability Model of Load Effect 85
4.4.4 Target Reliability 85
4.4.5 Safety Factor Design Results 85
References 87
Part II Unbonded Flexible Pipes
5 Unbonded Flexible Pipe Design 91
5.1 I ntroduction 91
5.2 Applications of Flexible Pipe 92
5.2.1 Flexible Risers 92
5.2.2 Flexible Flowlines 94
5.2.3 L oading and Offloading Hoses 94
5.2.4 Jumper Lines 96
5.2.5 D rilling Risers 97
5.3 Flexible Pipe System and Components 97
5.3.1 I nterlocked Steel Carcass 98
5.3.2 I nternal Polymer Sheath 99
5.3.3 Armor Layers 99
5.3.3.1 Pressure Armor 99
5.3.3.2 Tensile Armor 100
5.3.3.3 Composite Armor 100
5.3.4 E xternal Polymer Sheath 102
5.3.5 Other Layers and Configurations 102
5.3.6 Main Ancillaries 103
5.3.6.1 E nd Fittings 103
5.3.6.2 Bend Stiffener and Bellmouths 104
5.3.6.3 Bend Restrictor 105
5.3.6.4 Buoyancy Modules 106
5.3.6.5 Annulus Venting System 106
References 106
6 Design and Analyses of Unbonded Flexible Pipe 109
6.1 I ntroduction 109
6.2 Flexible Pipe Guidelines 110
6.2.1 API Specification 17K 110
6.2.2 API Specification 17J 111
6.2.2.1 Safety Against Collapse 112
6.2.2.2 D esign Criteria 112
6.2.3 API RP 17B 112
viii Contents
6.3 Material and Mechanical Properties 113
6.3.1 Properties of Sealing Components 114
6.3.1.1 Polymer 114
6.3.1.2 Steel 114
6.3.1.3 Fibres 115
6.3.2 Properties of Armor Components 115
6.3.2.1 Submerged Weight 116
6.3.2.2 Bending Stiffness and Curvature Radius 116
6.3.2.3 Axial Stiffness and Tension Capacity 116
6.3.2.4 Torque Stiffness and Torque Capacity 117
6.4 Analytical Solutions in Flexible Pipe Design 117
6.4.1 Overview 117
6.4.2 Analytical Modeling of Flexible Pipes 117
6.4.3 Analytical Method of Unbonded Flexible Pipes 118
6.4.4 Axis-Symmetric Behavior 120
6.4.4.1 Kinematic Restraint 120
6.4.4.2 Governing Equations 121
6.4.5 Bending Behavior 122
6.5 FE Analysis of Unbonded Flexible Pipe 123
6.5.1 Static Analysis 123
6.5.2 Fatigue Analysis 124
References 126
7 Unbonded Flexible Pipe Under Internal Pressure 129
7.1 I ntroduction 129
7.2 Analytical Solution 130
7.2.1 Polymeric Layer 131
7.2.2 Helically Wound Steel Layer 132
7.2.3 Assembly of Layers 134
7.3 FE Analysis 134
7.4 Results and Discussion 137
7.4.1 General 137
7.4.2 Axial Tension and End Displacement 138
7.4.3 Hoop Stress 138
7.4.4 Axial Stress 141
7.4.4.1 Axial Stress of Model A and Model B 141
7.4.4.2 Axial Stresses of Model C and Model D_141
7.4.5 Comparison of Mises Stress 144
7.5 Conclusions 145
References 146
8 Unbonded Flexible Pipe Under External Pressure 149
8.1 I ntroduction 149
8.2 Finite Element Analysis 151
8.2.1 Simplification 152
8.2.2 Modeling Description 152
8.2.3 Models with Different Stiffness Ratios 153
8.2.4 Models with Different D/t Ratios 154
Contents ix
8.3 FEM Results and Discussion 155
8.3.1 Prediction of Confined External Pressure 155
8.3.1.1 Same D/t Ratio with Different Stiffness Ratios 155
8.3.1.2 D ifferent D/t Ratios with Different Stiffness Ratios 157
8.3.2 Confined Post-Buckling Behavior 158
8.4 Analytical Solution 158
8.5 Test Study 161
8.5.1 Material Characteristics 162
8.5.2 Confined Collapse Tests 163
8.5.3 Test Results 165
8.6 Comparison of Three Methods 167
8.7 Conclusions 168
References 169
9 Unbonded Flexible Pipe Under Tension 171
9.1 I ntroduction 171
9.2 Tension Load 172
9.2.1 Helical Layer 172
9.2.2 Tube Layer 175
9.2.3 Principle of Virtual Work 175
9.3 Results and Discussion 177
9.4 Parametric Study 180
9.4.1 L ay Angle 181
9.4.2 D iameter-to-Thickness 183
9.5 Conclusions 184
References 185
10 Unbonded Flexible Pipe Under Bending 187
10.1 I ntroduction 187
10.2 Helical Layer within No-Slip Range 188
10.2.1 Geometry of Helical Layer 188
10.2.2 Bending Stiffness of Helical Layer 191
10.3 Helical Layer within Slip Range 192
10.3.1 Critical Curvature 192
10.3.2 Axial Force in Helical Wire within Slip Range 194
10.3.3 Axial Force in Helical Wire within No-Slip Range 194
10.3.4 Bending Stiffness of Helical Layer 196
References 197
11 Unbonded Flexible Pipe Under Tension and Internal Pressure 199
11.1 I ntroduction 199
11.2 Analytical Solution 200
11.3 FE Analysis 200
11.3.1 Case 1: Tension Only 201
11.3.2 Case 2: Internal Pressure Only 202
11.3.3 Case 3: Combined Tension and Internal Pressure 202
x Contents
11.4 Results and Discussion 202
11.5 Conclusions 208
References 208
12 Cross-Sectional Design and Case Study for Unbonded Flexible Pipes 211
12.1 I ntroduction 211
12.2 Cross-Sectional Design 212
12.2.1 General Design Requirements 212
12.2.2 Manufacturing Configuration and Material Qualification 213
12.2.2.1 Carcass 213
12.2.2.2 Pressure Sheath 213
12.2.2.3 Pressure Armor 213
12.2.2.4 Tensile Armor 214
12.2.2.5 Tape 214
12.2.2.6 Shield 214
12.3 Case Study 214
12.3.1 D esign Procedure 214
12.3.2 D esign Requirement 214
12.3.3 D esign Method 215
12.3.3.1 Strength Design for Axisymmetric Loads 215
12.3.3.2 Collapse Resistance Design 216
12.3.4 D esign Results 216
12.3.5 L oad Analysis 217
12.3.6 FE Analysis 218
12.4 Conclusions 219
References 220
13 Fatigue Analysis of Unbonded Flexible Pipe 223
13.1 I ntroduction 223
13.2 Theoretical Approach 224
13.2.1 Assumptions 224
13.2.2 E nvironment Conditions 224
13.2.3 Transposition of Forces and Bending Moments 225
13.2.4 Fatigue Design Criteria 225
13.2.4.1 S-N Curves 225
13.2.4.2 Miner's rule 225
13.3 Case Study 226
13.3.1 I ntroduction 226
13.3.2 Base Case 227
13.4 Conclusions 230
References 230
Contents xi
Part III Steel Reinforced Flexible Pipes
14 Steel Reinforced Flexible Pipe Under Internal Pressure 235
14.1 I ntroduction 235
14.2 Applications 235
14.2.1 Offshore 236
14.2.2 Onshore 236
14.2.3 Rehabilitation 237
14.3 D esign and Manufacturing 237
14.3.1 D esign Codes 237
14.3.2 Manufacturing 237
14.3.2.1 I ntroduction 237
14.3.2.2 I nner and Outer Layers 238
14.3.2.3 Steel Strip Reinforcement Layers 238
14.3.2.4 E nd Fitting 238
14.4 Analytical Solution 240
14.4.1 Mechanical Properties 240
14.4.2 Assumptions 242
14.4.3 Stress Analysis 242
14.4.3.1 L ayer Properties 244
14.4.3.2 Stress-Strain Relations of HDPE Layers 246
14.4.3.3 Stress-Strain Relations of Steel Strip Layers 247
14.4.4 Boundary Condition 248
14.4.4.1 Stress Boundary Condition 248
14.4.4.2 I nterface Condition 248
14.4.4.3 E quilibrium Equation of Axial Force 248
14.4.4.4 Torsion Balance Equation 248
14.5 FE Analysis 249
14.6 Results and Discussion 249
14.6.1 Stress Analysis on Layer 2 249
14.6.2 Stress Analysis Between Layers 252
14.7 Conclusions 253
References 254
15 Steel Reinforced Flexible Pipe Under External Pressure 255
15.1 I ntroduction 255
15.2 E xperimental Tests 256
15.2.1 Material Characteristics 256
15.2.2 Collapse Experiment 256
15.2.3 E xperimental Results 258
15.3 FE Analysis 258
15.4 Simplified Estimation for Collapse Pressure 262
15.5 Parametric Study 264
15.6 Conclusions 266
References 267
xii Contents
16 Steel Reinforced Flexible Pipe Under Pure Tension 269
16.1 I ntroduction 269
16.2 E xperimental Tests 270
16.2.1 Test Processes 270
16.2.2 Test Results and Discussions 270
16.3 FE Analysis 273
16.3.1 E lements and Interactions 273
16.3.2 L oad and Boundary Conditions 274
16.3.3 Material Properties 274
16.4 Comparison and Discussions 275
16.4.1 Comparison between Test and FE Analysis 275
16.4.2 Mechanical Response of PE Layers 276
16.4.3 Mechanical Response of Steel Strips 279
16.5 Conclusions 281
References 282
17 Steel Reinforced Flexible Pipe Under Bending 283
17.1 I ntroduction 283
17.2 FE Analysis 284
17.2.1 Model and Material Properties 284
17.2.2 L oads and Boundary Conditions 285
17.2.3 Analysis Results 285
17.3 Mechanical Behaviors and Discussions 287
17.3.1 I nner PE Layer 287
17.3.2 Outer PE Layer 289
17.3.3 Steel Strip Layers 290
17.4 Conclusions 291
References 291
18 Steel Reinforced Flexible Pipe Under Combined Internal
Pressure and Tension 293
18.1 I ntroduction 293
18.2 Analytical Solution 293
18.2.1 Strain Analysis 293
18.2.2 Stress Analysis 294
18.2.3 Boundary Conditions 297
18.3 I nner HDPE layer 297
18.3.1 Reinforcement Layers 298
18.3.2 Outer HDPE Layer 298
18.3.3 E quilibrium Equation 299
18.3.4 Solution Chart 299
18.4 Finite Element Analysis 300
18.4.1 I ntroduction 300
18.4.2 Material Properties 300
18.4.3 FE Model 301
18.4.4 Boundary Conditions 304
Contents xiii
18.5 Results and Discussion 304
18.5.1 Comparison of Methods 304
18.5.2 L oad Steps 305
18.5.3 Axial Tension Followed by Internal Pressure 306
18.5.3.1 Stress Response 306
18.5.3.2 Failure Behavior 306
18.5.4 I nternal Pressure Followed by Axial Tension 307
18.6 Conclusions 309
References 310
19 Steel Reinforced Flexible Pipe Under Combined
Internal Pressure and Bending 311
19.1 I ntroduction 311
19.2 Analytical Solution 312
19.3 FE Analysis 316
19.3.1 Finite Element Model 316
19.3.2 Boundary Conditions 316
19.3.3 Analysis Results 317
19.4 Summary 319
References 321
20 Steel Reinforced Flexible Pipe Under Combined
Bending and External Pressure 323
20.1 I ntroduction 323
20.2 E xperimental Tests 324
20.2.1 Test Procedure 324
20.2.2 Test Results and Discussions 325
20.3 FE Analysis 326
20.3.1 Finite Element Modeling 327
20.3.2 Comparison of Test and Analysis Results 327
20.4 Analysis Results and Discussions 329
20.5 Conclusions 330
References 331
21 Cross-Sectional Design and Case Study for Steel Reinforced Flexible Pipe 333
21.1 I ntroduction 333
21.2 Mechanical Behaviors 334
21.3 Cross-Sectional Design 335
21.3.1 D esign Requirement 335
21.3.2 Strength Capacity 336
21.4 Case Study 338
21.4.1 General 338
21.4.2 D esign Analysis 339
21.4.2.1 Preliminary Analysis 339
21.4.2.2 FE Analysis 339
21.5 Conclusions 340
References 340
22 Damage Assessment for Steel Reinforced Flexible Pipe 343
22.1 I ntroduction 343
22.2 D amage Analysis of Outer Layer 344
22.2.1 General 344
22.2.2 FE Analysis 344
22.2.3 Material Parameters 345
22.2.4 Modeling of Damage Analysis 346
22.2.5 Analysis Results 347
22.3 I nfluence of Different Intervals 351
22.4 E ffects of Insufficient Strength in Steel Strip 352
References 354
Part IV Bonded Flexible Pipes
23 Bonded Flexible Rubber Pipes 357
23.1 I ntroduction 357
23.1.1 Constructions of Bonded Flexible Pipe 358
23.1.2 Types of Bonded Flexible Pipe 359
23.2 D esign and Applications 360
23.2.1 I ntroduction 360
23.2.2 D esign Criteria 361
23.2.3 Hose Design Activities 361
23.2.4 Bonded Flexible Hose Design 363
23.2.5 E nd Fittings 365
23.2.6 Materials 366
23.2.7 Applications 369
23.3 Failure Modes 371
23.3.1 E arly Failures 372
23.3.2 Random Failures 373
23.3.3 Wear-Down Failures 373
23.3.4 E xamples of Hose Failures 373
23.4 I ntegrity Management 374
23.4.1 Risk Analysis 374
23.4.2 Risk Evaluation Process 374
23.4.3 Actions Following Risk Assessment 375
References 376
24 Nonmetallic Bonded Flexible Pipe Under Internal Pressure 377
24.1 I ntroduction 377
24.1.1 N omenclature 378
24.2 E xperimental Tests 379
24.2.1 Material Properties 379
24.2.2 Burst Tests 380
24.3 Analytical Solution 381
24.3.1 I ntroduction 381
24.3.2 Assumptions 381
xiv Contents
Contents xv
24.3.3 Coordinate Systems 382
24.3.4 I nner Layer and Outer Layer 383
24.3.5 Reinforced Layers 385
24.3.6 Boundary Conditions 387
24.3.7 Failure Criterion 388
24.3.8 Burst Pressure Calculation 388
24.4 Finite Element Analysis 389
24.5 Results and Comparison 391
References 392
25 Nonmetallic Bonded Flexible Pipe Under External Pressure 393
25.1 I ntroduction 393
25.2 Analytical Solution of Collapse 394
25.2.1 Kinematics 394
25.2.2 Materials of Each Layer 395
25.2.2.1 PE_395
25.2.2.2 Reinforced Layer 395
25.2.2.3 The Material Plasticity 396
25.2.3 Principle of Virtual Work 397
25.2.4 Amendment of Radius and Wall Thickness 398
25.2.5 Analytical Method 399
25.3 FE Analysis 400
25.3.1 I ntroduction 400
25.3.2 FE Modeling 401
25.4 E xample of Collapse Analysis 401
25.4.1 I ntroduction 401
25.4.2 I nput Data 401
25.4.3 Pressure-Ovality Curves 402
25.5 Sensitivity Analysis 403
25.5.1 E ffect of Initial Imperfections 404
25.5.2 E ffect of Shear Deformation 404
25.5.3 E ffect of Pre-Buckling Deformation 405
References 406
26 Nonmetallic Bonded Flexible Pipe Under Bending 407
26.1 I ntroduction 407
26.2 Analytical Solution 409
26.2.1 Assumptions 409
26.2.2 Kinematics 409
26.2.3 Models of Material 410
26.2.3.1 Mechanical Behaviors of HDPE_410
26.2.3.2 Mechanical Behaviors of Fiber Reinforced Layer 412
26.2.4 Constitutive Model for RTP 415
26.2.5 Principle of Virtual Work 415
26.3 FE Analysis 416
26.4 E xperiment Test 418
xvi Contents
26.5 Results and Discussion 419
26.6 Parametric Studies 421
26.6.1 Wall-Thickness 421
26.6.2 D iameter of Pipe 422
26.6.3 D /t Ratio 422
26.6.4 I nitial Ovality 423
26.7 Conclusions 424
References 424
Appendix 426
27 Nonmetallic Bonded Flexible Pipe Under Combined
Tension and Internal Pressure 429
27.1 I ntroduction 429
27.2 N onlinear Analytical Solution 431
27.2.1 Fundamental Assumptions 431
27.2.2 Simplification of Reinforcement Layers 432
27.2.3 Kinematics of a Single Wire 433
27.2.4 D eformation of Cross Section 434
27.2.5 E quilibrium Equation 440
27.2.6 Constitutive Model 442
27.2.7 Solution Method 442
27.3 Finite Element Model 442
27.3.1 Model Design and Meshing 443
27.3.2 Materials 444
27.3.3 Constraints 444
27.3.4 Boundary Conditions and Loadings 445
27.4 Results and Discussion 445
27.4.1 Tension-Extension Relation 445
27.4.2 Stress in Kevlar Wires 446
27.4.3 Radial Deformation 446
27.4.4 D iscussion 446
27.5 Parametric Study 448
27.5.1 I nternal Pressure 449
27.5.2 L ay Angle 450
27.5.3 D /t Ratio 450
27.5.4 Amount of Kevlar Wires 451
27.6 Conclusions 452
References 453
28 Nonmetallic Bonded Flexible Pipe Under Combined
External Pressure and Bending 455
28.1 General 455
28.2 I ntroduction 455
28.3 Analytical Solution 457
28.3.1 Kinematics 457
28.3.2 Material Simplification 458
28.3.3 Constitutive Model 462
Contents xvii
28.3.4 Principle of Virtual Work 462
28.3.5 Amendment of Radius and Wall Thickness 463
28.3.6 Solution Method 463
28.4 Finite Element Model 464
28.5 Results and Discussions 465
28.5.1 Collapse of RTP Under External Pressure 465
28.5.2 Collapse of RTP Under Pure Bending 468
28.5.3 Collapse of RTP Under Combined Bending
and External Pressure 471
28.6 Conclusions 473
References 474
29 Fibre Glass Reinforced Flexible Pipes Under Internal Pressure 475
29.1 I ntroduction 475
29.2 Analytical Solution 476
29.2.1 Assumptions 476
29.2.2 Stress Analysis 476
29.2.3 Boundary Conditions 479
29.3 Finite Element Analysis 480
29.4 Results and Discussions 481
29.5 Winding Angle 483
29.6 Conclusions 484
References 485
30 Fibre Glass Reinforced Flexible Pipe Under External Pressure 487
30.1 I ntroduction 487
30.2 FE Analysis 488
30.2.1 I ntroduction 488
30.2.2 Geometrical Parameters and Material Properties 489
30.2.3 FE Modeling 490
30.3 Results and Discussions 491
30.3.1 I ntroduction 491
30.3.2 I nitial Imperfection 491
30.3.2.1 I nitial Ovality 491
30.3.2.2 I nitial Wall Eccentricity 492
30.3.3 Geometrical Configurations 494
30.3.3.1 D iameter Over Thickness Ratio D1/t1 of
Outer PE Layer 494
30.3.3.2 N umber of Reinforced Layers 495
30.3.3.3 D iameter Over Thickness Ratio D2/t2
of Inner Layer 496
30.3.4 Material 496
30.5 Conclusions 497
References 498
xviii Contents
31 Steel Wire Bonded Flexible Pipe Under Internal Pressure 499
31.1 I ntroduction 499
31.2 Analytical Solution 501
31.2.1 General 501
31.2.2 Stress and Strain Analysis 501
31.2.3 Simplification of Reinforced Layers 503
31.3 Finite Element Analysis 504
31.3.1 General 504
31.3.2 ABAQUS Modeling 504
31.4 Analysis Results 506
31.4.1 Comparison of Strains 506
31.4.2 E ffect of Winding Angle 507
31.5 E xperimental Test 508
31.5.1 General 508
31.5.2 Test Results 508
31.6 E ngineering Burst Pressure Formula 509
References 510
32 Steel Wire Bonded Flexible Pipe Under External Pressure 513
32.1 I ntroduction 513
32.2 Analytical solution 514
32.2.1 Fundamental Assumptions 514
32.2.2 N onlinear Ring Theory 514
32.2.3 Constitutive Relation of Material 516
32.2.4 Principle of Virtual Work Equation 518
32.3 N umerical Simulations 520
32.4 E xperimental Test 523
32.5 Conclusions 525
References 525
33 Steel Wire Bonded Flexible Pipe Under Bending and Internal Pressure 527
33.1 I ntroduction 527
33.2 Analytical Solution 528
33.2.1 Principle of Virtual Work 529
33.2.2 Burst Pressure of PSP in Axial Direction 531
33.2.3 Burst Pressure of PSP in Circumferential Direction 531
33.2.4 Constitutive Model for Materials 532
33.3 N umerical Simulations 535
33.4 Pure Bending Experimental Test 535
33.4.1 Test 535
33.4.2 Results and Discussion 537
33.5 Combined Internal Pressure and Bending Experimental Test 538
33.5.1 Test Facilities 539
33.5.2 Test Procedure 539
33.5.3 Test Results 540
33.6 Comparison of Results 540
33.7 Conclusions 541
References 542
Contents xix
34 Cross-Sectional Design and Case Study for Steel Wire
Bonded Flexible Pipe 543
34.1 I ntroduction 543
34.2 Cross-Sectional Design 544
34.2.1 D esign Procedure 544
34.2.2 D esign Parameters 544
34.2.3 Properties and Capacities 546
34.3 Case Study 550
34.4 V alidation by FE Model 551
34.5 Conclusions 555
References 555
35 Damage Assessment for Steel Wire Bonded Flexible Pipes 557
35.1 I ntroduction 557
35.2 Analytical Method 558
35.2.1 Basic Assumptions 558
35.2.2 Stress-Strain Relationship 558
35.3 Finite Element Analysis 564
35.4 Comparison between Analytical Method and FEM 565
35.4.1 E ffect of Steel Wire Winding Angle 567
35.4.2 E ffects of Steel Wire Diameter 568
35.4.3 E ffects of Missing Steel Wire 568
35.4.4 E ffect of Damaged Inner and Outer PE Layers 569
35.4.5 E ffects of Layer Interfacial Peeling 569
35.5 Summary 572
References 573
36 Third-Party Damage for Steel Wire Bonded Flexible Pipe 575
36.1 I ntroduction 575
36.2 Pipeline, Soil and Tamper Parameters 576
36.3 Finite Element Model 577
36.4 L oading and Boundary Conditions 578
36.5 Analysis Results 578
36.5.1 D ynamic Response 579
36.5.2 Tamping Velocity 581
36.5.3 Buried Depth 581
36.6 Summary 583
References 583 Index 585
About the Authors xxiii
Part I Design and Analysis
1 Flexible Pipes and Limit-States Design 3
1.1 I ntroduction 3
1.2 Applications of Flexible Pipe 3
1.2.1 Metal-Based Flexible Pipes 5
1.2.2 Composite-Based Flexible Pipes 7
1.2.3 D esign Codes and Specifications 10
1.3 Comparison between Flexible Pipes and Rigid Pipes 12
1.3.1 Unbonded Flexible Riser vs. Rigid Steel Riser 12
1.3.2 Flexible Jumper vs. Rigid Steel Jumper 12
1.3.3 Flexible Composite Pipe vs. Rigid Pipe 13
1.3.3.1 Material Costs 14
1.3.3.2 I nstallation Costs 14
1.3.3.3 Operational Costs 15
1.3.3.4 Comparison Example 15
1.4 Failure Mode and Design Criteria 15
1.4.1 Unbonded Flexible Pipe 15
1.4.1.1 Failure Modes 15
1.4.1.2 D esign Criteria 17
1.4.2 Flexible Composite Pipe 20
1.4.2.1 Failure Modes 20
1.4.2.2 D esign Criteria 20
1.5 L imit State Design 24
1.5.1 L imit States 24
1.5.2 Reliability-Based Methods 25
References 26
2 Materials and Aging 29
2.1 I ntroduction 29
2.1.1 Unbonded Flexible Pipes 30
2.1.2 Flexible Composite Pipes 34
vi Contents
2.2 Metallic Material 35
2.2.1 Stainless Steel 35
2.2.2 Carbon Steel 36
2.3 Polymer Material 36
2.3.1 Annulus 36
2.3.2 Chemical Resistance 39
2.3.3 Permeation and Permeation Control Systems 41
2.3.3.1 Theory of Gas Permeation 41
2.3.3.2 Permeation Calculation 42
2.3.4 Anti H2S Layer 44
2.4 Aging 45
2.4.1 N onmetallic Material 46
2.4.2 Metallic Material 48
References 49
3 Ancillary Equipment and End Fitting Design 51
3.1 I ntroduction 51
3.1.1 D esign Criteria 51
3.2 Bend Stiffeners and Bellmouths 53
3.2.1 I ntroduction 53
3.2.2 D esign Criteria and Failure Modes 55
3.2.3 D esign Considerations 56
3.2.4 Bellmouths 57
3.3 Bend Restrictor 58
3.4 Buoyancy Modules 59
3.5 Cathodic Protection 60
3.6 Annulus Venting System 61
3.7 E nd Fittings 63
3.7.1 Unbonded Flexible Pipes 64
3.7.1.1 D esign Criteria 64
3.7.1.2 Metallic Materials 66
3.7.1.3 E nd Fittings by Different Manufacturers 66
3.7.2 Flexible Composite Pipes 68
3.7.2.1 D esign Criteria 70
3.7.2.2 Materials 70
3.7.2.3 E nd Fitting Types 71
3.7.2.4 I nstallation 72
References 74
4 Reliability-Based Design Factors 75
4.1 Introduction 75
4.2 Failure Probability 76
4.2.1 L imit State and Failure Mode 76
4.2.2 Failure Probability 76
4.3 Safety Factor Based on Reliability 77
4.3.1 Uncertainties of Resistance and Load Effect 78
4.3.2 L RFD Formulation 79
4.3.3 D esign Process 79
Contents vii
4.4 D esign Example 82
4.4.1 L imit State Function 83
4.4.1.1 Resistance Model for Inner Pressure Load 83
4.4.1.2 L imit State Function 83
4.4.2 Probability Model of Resistance 83
4.4.2.1 Probability Distribution of Resistance Parameters 83
4.4.2.2 Probability Model of Resistance 84
4.4.3 Probability Model of Load Effect 85
4.4.4 Target Reliability 85
4.4.5 Safety Factor Design Results 85
References 87
Part II Unbonded Flexible Pipes
5 Unbonded Flexible Pipe Design 91
5.1 I ntroduction 91
5.2 Applications of Flexible Pipe 92
5.2.1 Flexible Risers 92
5.2.2 Flexible Flowlines 94
5.2.3 L oading and Offloading Hoses 94
5.2.4 Jumper Lines 96
5.2.5 D rilling Risers 97
5.3 Flexible Pipe System and Components 97
5.3.1 I nterlocked Steel Carcass 98
5.3.2 I nternal Polymer Sheath 99
5.3.3 Armor Layers 99
5.3.3.1 Pressure Armor 99
5.3.3.2 Tensile Armor 100
5.3.3.3 Composite Armor 100
5.3.4 E xternal Polymer Sheath 102
5.3.5 Other Layers and Configurations 102
5.3.6 Main Ancillaries 103
5.3.6.1 E nd Fittings 103
5.3.6.2 Bend Stiffener and Bellmouths 104
5.3.6.3 Bend Restrictor 105
5.3.6.4 Buoyancy Modules 106
5.3.6.5 Annulus Venting System 106
References 106
6 Design and Analyses of Unbonded Flexible Pipe 109
6.1 I ntroduction 109
6.2 Flexible Pipe Guidelines 110
6.2.1 API Specification 17K 110
6.2.2 API Specification 17J 111
6.2.2.1 Safety Against Collapse 112
6.2.2.2 D esign Criteria 112
6.2.3 API RP 17B 112
viii Contents
6.3 Material and Mechanical Properties 113
6.3.1 Properties of Sealing Components 114
6.3.1.1 Polymer 114
6.3.1.2 Steel 114
6.3.1.3 Fibres 115
6.3.2 Properties of Armor Components 115
6.3.2.1 Submerged Weight 116
6.3.2.2 Bending Stiffness and Curvature Radius 116
6.3.2.3 Axial Stiffness and Tension Capacity 116
6.3.2.4 Torque Stiffness and Torque Capacity 117
6.4 Analytical Solutions in Flexible Pipe Design 117
6.4.1 Overview 117
6.4.2 Analytical Modeling of Flexible Pipes 117
6.4.3 Analytical Method of Unbonded Flexible Pipes 118
6.4.4 Axis-Symmetric Behavior 120
6.4.4.1 Kinematic Restraint 120
6.4.4.2 Governing Equations 121
6.4.5 Bending Behavior 122
6.5 FE Analysis of Unbonded Flexible Pipe 123
6.5.1 Static Analysis 123
6.5.2 Fatigue Analysis 124
References 126
7 Unbonded Flexible Pipe Under Internal Pressure 129
7.1 I ntroduction 129
7.2 Analytical Solution 130
7.2.1 Polymeric Layer 131
7.2.2 Helically Wound Steel Layer 132
7.2.3 Assembly of Layers 134
7.3 FE Analysis 134
7.4 Results and Discussion 137
7.4.1 General 137
7.4.2 Axial Tension and End Displacement 138
7.4.3 Hoop Stress 138
7.4.4 Axial Stress 141
7.4.4.1 Axial Stress of Model A and Model B 141
7.4.4.2 Axial Stresses of Model C and Model D_141
7.4.5 Comparison of Mises Stress 144
7.5 Conclusions 145
References 146
8 Unbonded Flexible Pipe Under External Pressure 149
8.1 I ntroduction 149
8.2 Finite Element Analysis 151
8.2.1 Simplification 152
8.2.2 Modeling Description 152
8.2.3 Models with Different Stiffness Ratios 153
8.2.4 Models with Different D/t Ratios 154
Contents ix
8.3 FEM Results and Discussion 155
8.3.1 Prediction of Confined External Pressure 155
8.3.1.1 Same D/t Ratio with Different Stiffness Ratios 155
8.3.1.2 D ifferent D/t Ratios with Different Stiffness Ratios 157
8.3.2 Confined Post-Buckling Behavior 158
8.4 Analytical Solution 158
8.5 Test Study 161
8.5.1 Material Characteristics 162
8.5.2 Confined Collapse Tests 163
8.5.3 Test Results 165
8.6 Comparison of Three Methods 167
8.7 Conclusions 168
References 169
9 Unbonded Flexible Pipe Under Tension 171
9.1 I ntroduction 171
9.2 Tension Load 172
9.2.1 Helical Layer 172
9.2.2 Tube Layer 175
9.2.3 Principle of Virtual Work 175
9.3 Results and Discussion 177
9.4 Parametric Study 180
9.4.1 L ay Angle 181
9.4.2 D iameter-to-Thickness 183
9.5 Conclusions 184
References 185
10 Unbonded Flexible Pipe Under Bending 187
10.1 I ntroduction 187
10.2 Helical Layer within No-Slip Range 188
10.2.1 Geometry of Helical Layer 188
10.2.2 Bending Stiffness of Helical Layer 191
10.3 Helical Layer within Slip Range 192
10.3.1 Critical Curvature 192
10.3.2 Axial Force in Helical Wire within Slip Range 194
10.3.3 Axial Force in Helical Wire within No-Slip Range 194
10.3.4 Bending Stiffness of Helical Layer 196
References 197
11 Unbonded Flexible Pipe Under Tension and Internal Pressure 199
11.1 I ntroduction 199
11.2 Analytical Solution 200
11.3 FE Analysis 200
11.3.1 Case 1: Tension Only 201
11.3.2 Case 2: Internal Pressure Only 202
11.3.3 Case 3: Combined Tension and Internal Pressure 202
x Contents
11.4 Results and Discussion 202
11.5 Conclusions 208
References 208
12 Cross-Sectional Design and Case Study for Unbonded Flexible Pipes 211
12.1 I ntroduction 211
12.2 Cross-Sectional Design 212
12.2.1 General Design Requirements 212
12.2.2 Manufacturing Configuration and Material Qualification 213
12.2.2.1 Carcass 213
12.2.2.2 Pressure Sheath 213
12.2.2.3 Pressure Armor 213
12.2.2.4 Tensile Armor 214
12.2.2.5 Tape 214
12.2.2.6 Shield 214
12.3 Case Study 214
12.3.1 D esign Procedure 214
12.3.2 D esign Requirement 214
12.3.3 D esign Method 215
12.3.3.1 Strength Design for Axisymmetric Loads 215
12.3.3.2 Collapse Resistance Design 216
12.3.4 D esign Results 216
12.3.5 L oad Analysis 217
12.3.6 FE Analysis 218
12.4 Conclusions 219
References 220
13 Fatigue Analysis of Unbonded Flexible Pipe 223
13.1 I ntroduction 223
13.2 Theoretical Approach 224
13.2.1 Assumptions 224
13.2.2 E nvironment Conditions 224
13.2.3 Transposition of Forces and Bending Moments 225
13.2.4 Fatigue Design Criteria 225
13.2.4.1 S-N Curves 225
13.2.4.2 Miner's rule 225
13.3 Case Study 226
13.3.1 I ntroduction 226
13.3.2 Base Case 227
13.4 Conclusions 230
References 230
Contents xi
Part III Steel Reinforced Flexible Pipes
14 Steel Reinforced Flexible Pipe Under Internal Pressure 235
14.1 I ntroduction 235
14.2 Applications 235
14.2.1 Offshore 236
14.2.2 Onshore 236
14.2.3 Rehabilitation 237
14.3 D esign and Manufacturing 237
14.3.1 D esign Codes 237
14.3.2 Manufacturing 237
14.3.2.1 I ntroduction 237
14.3.2.2 I nner and Outer Layers 238
14.3.2.3 Steel Strip Reinforcement Layers 238
14.3.2.4 E nd Fitting 238
14.4 Analytical Solution 240
14.4.1 Mechanical Properties 240
14.4.2 Assumptions 242
14.4.3 Stress Analysis 242
14.4.3.1 L ayer Properties 244
14.4.3.2 Stress-Strain Relations of HDPE Layers 246
14.4.3.3 Stress-Strain Relations of Steel Strip Layers 247
14.4.4 Boundary Condition 248
14.4.4.1 Stress Boundary Condition 248
14.4.4.2 I nterface Condition 248
14.4.4.3 E quilibrium Equation of Axial Force 248
14.4.4.4 Torsion Balance Equation 248
14.5 FE Analysis 249
14.6 Results and Discussion 249
14.6.1 Stress Analysis on Layer 2 249
14.6.2 Stress Analysis Between Layers 252
14.7 Conclusions 253
References 254
15 Steel Reinforced Flexible Pipe Under External Pressure 255
15.1 I ntroduction 255
15.2 E xperimental Tests 256
15.2.1 Material Characteristics 256
15.2.2 Collapse Experiment 256
15.2.3 E xperimental Results 258
15.3 FE Analysis 258
15.4 Simplified Estimation for Collapse Pressure 262
15.5 Parametric Study 264
15.6 Conclusions 266
References 267
xii Contents
16 Steel Reinforced Flexible Pipe Under Pure Tension 269
16.1 I ntroduction 269
16.2 E xperimental Tests 270
16.2.1 Test Processes 270
16.2.2 Test Results and Discussions 270
16.3 FE Analysis 273
16.3.1 E lements and Interactions 273
16.3.2 L oad and Boundary Conditions 274
16.3.3 Material Properties 274
16.4 Comparison and Discussions 275
16.4.1 Comparison between Test and FE Analysis 275
16.4.2 Mechanical Response of PE Layers 276
16.4.3 Mechanical Response of Steel Strips 279
16.5 Conclusions 281
References 282
17 Steel Reinforced Flexible Pipe Under Bending 283
17.1 I ntroduction 283
17.2 FE Analysis 284
17.2.1 Model and Material Properties 284
17.2.2 L oads and Boundary Conditions 285
17.2.3 Analysis Results 285
17.3 Mechanical Behaviors and Discussions 287
17.3.1 I nner PE Layer 287
17.3.2 Outer PE Layer 289
17.3.3 Steel Strip Layers 290
17.4 Conclusions 291
References 291
18 Steel Reinforced Flexible Pipe Under Combined Internal
Pressure and Tension 293
18.1 I ntroduction 293
18.2 Analytical Solution 293
18.2.1 Strain Analysis 293
18.2.2 Stress Analysis 294
18.2.3 Boundary Conditions 297
18.3 I nner HDPE layer 297
18.3.1 Reinforcement Layers 298
18.3.2 Outer HDPE Layer 298
18.3.3 E quilibrium Equation 299
18.3.4 Solution Chart 299
18.4 Finite Element Analysis 300
18.4.1 I ntroduction 300
18.4.2 Material Properties 300
18.4.3 FE Model 301
18.4.4 Boundary Conditions 304
Contents xiii
18.5 Results and Discussion 304
18.5.1 Comparison of Methods 304
18.5.2 L oad Steps 305
18.5.3 Axial Tension Followed by Internal Pressure 306
18.5.3.1 Stress Response 306
18.5.3.2 Failure Behavior 306
18.5.4 I nternal Pressure Followed by Axial Tension 307
18.6 Conclusions 309
References 310
19 Steel Reinforced Flexible Pipe Under Combined
Internal Pressure and Bending 311
19.1 I ntroduction 311
19.2 Analytical Solution 312
19.3 FE Analysis 316
19.3.1 Finite Element Model 316
19.3.2 Boundary Conditions 316
19.3.3 Analysis Results 317
19.4 Summary 319
References 321
20 Steel Reinforced Flexible Pipe Under Combined
Bending and External Pressure 323
20.1 I ntroduction 323
20.2 E xperimental Tests 324
20.2.1 Test Procedure 324
20.2.2 Test Results and Discussions 325
20.3 FE Analysis 326
20.3.1 Finite Element Modeling 327
20.3.2 Comparison of Test and Analysis Results 327
20.4 Analysis Results and Discussions 329
20.5 Conclusions 330
References 331
21 Cross-Sectional Design and Case Study for Steel Reinforced Flexible Pipe 333
21.1 I ntroduction 333
21.2 Mechanical Behaviors 334
21.3 Cross-Sectional Design 335
21.3.1 D esign Requirement 335
21.3.2 Strength Capacity 336
21.4 Case Study 338
21.4.1 General 338
21.4.2 D esign Analysis 339
21.4.2.1 Preliminary Analysis 339
21.4.2.2 FE Analysis 339
21.5 Conclusions 340
References 340
22 Damage Assessment for Steel Reinforced Flexible Pipe 343
22.1 I ntroduction 343
22.2 D amage Analysis of Outer Layer 344
22.2.1 General 344
22.2.2 FE Analysis 344
22.2.3 Material Parameters 345
22.2.4 Modeling of Damage Analysis 346
22.2.5 Analysis Results 347
22.3 I nfluence of Different Intervals 351
22.4 E ffects of Insufficient Strength in Steel Strip 352
References 354
Part IV Bonded Flexible Pipes
23 Bonded Flexible Rubber Pipes 357
23.1 I ntroduction 357
23.1.1 Constructions of Bonded Flexible Pipe 358
23.1.2 Types of Bonded Flexible Pipe 359
23.2 D esign and Applications 360
23.2.1 I ntroduction 360
23.2.2 D esign Criteria 361
23.2.3 Hose Design Activities 361
23.2.4 Bonded Flexible Hose Design 363
23.2.5 E nd Fittings 365
23.2.6 Materials 366
23.2.7 Applications 369
23.3 Failure Modes 371
23.3.1 E arly Failures 372
23.3.2 Random Failures 373
23.3.3 Wear-Down Failures 373
23.3.4 E xamples of Hose Failures 373
23.4 I ntegrity Management 374
23.4.1 Risk Analysis 374
23.4.2 Risk Evaluation Process 374
23.4.3 Actions Following Risk Assessment 375
References 376
24 Nonmetallic Bonded Flexible Pipe Under Internal Pressure 377
24.1 I ntroduction 377
24.1.1 N omenclature 378
24.2 E xperimental Tests 379
24.2.1 Material Properties 379
24.2.2 Burst Tests 380
24.3 Analytical Solution 381
24.3.1 I ntroduction 381
24.3.2 Assumptions 381
xiv Contents
Contents xv
24.3.3 Coordinate Systems 382
24.3.4 I nner Layer and Outer Layer 383
24.3.5 Reinforced Layers 385
24.3.6 Boundary Conditions 387
24.3.7 Failure Criterion 388
24.3.8 Burst Pressure Calculation 388
24.4 Finite Element Analysis 389
24.5 Results and Comparison 391
References 392
25 Nonmetallic Bonded Flexible Pipe Under External Pressure 393
25.1 I ntroduction 393
25.2 Analytical Solution of Collapse 394
25.2.1 Kinematics 394
25.2.2 Materials of Each Layer 395
25.2.2.1 PE_395
25.2.2.2 Reinforced Layer 395
25.2.2.3 The Material Plasticity 396
25.2.3 Principle of Virtual Work 397
25.2.4 Amendment of Radius and Wall Thickness 398
25.2.5 Analytical Method 399
25.3 FE Analysis 400
25.3.1 I ntroduction 400
25.3.2 FE Modeling 401
25.4 E xample of Collapse Analysis 401
25.4.1 I ntroduction 401
25.4.2 I nput Data 401
25.4.3 Pressure-Ovality Curves 402
25.5 Sensitivity Analysis 403
25.5.1 E ffect of Initial Imperfections 404
25.5.2 E ffect of Shear Deformation 404
25.5.3 E ffect of Pre-Buckling Deformation 405
References 406
26 Nonmetallic Bonded Flexible Pipe Under Bending 407
26.1 I ntroduction 407
26.2 Analytical Solution 409
26.2.1 Assumptions 409
26.2.2 Kinematics 409
26.2.3 Models of Material 410
26.2.3.1 Mechanical Behaviors of HDPE_410
26.2.3.2 Mechanical Behaviors of Fiber Reinforced Layer 412
26.2.4 Constitutive Model for RTP 415
26.2.5 Principle of Virtual Work 415
26.3 FE Analysis 416
26.4 E xperiment Test 418
xvi Contents
26.5 Results and Discussion 419
26.6 Parametric Studies 421
26.6.1 Wall-Thickness 421
26.6.2 D iameter of Pipe 422
26.6.3 D /t Ratio 422
26.6.4 I nitial Ovality 423
26.7 Conclusions 424
References 424
Appendix 426
27 Nonmetallic Bonded Flexible Pipe Under Combined
Tension and Internal Pressure 429
27.1 I ntroduction 429
27.2 N onlinear Analytical Solution 431
27.2.1 Fundamental Assumptions 431
27.2.2 Simplification of Reinforcement Layers 432
27.2.3 Kinematics of a Single Wire 433
27.2.4 D eformation of Cross Section 434
27.2.5 E quilibrium Equation 440
27.2.6 Constitutive Model 442
27.2.7 Solution Method 442
27.3 Finite Element Model 442
27.3.1 Model Design and Meshing 443
27.3.2 Materials 444
27.3.3 Constraints 444
27.3.4 Boundary Conditions and Loadings 445
27.4 Results and Discussion 445
27.4.1 Tension-Extension Relation 445
27.4.2 Stress in Kevlar Wires 446
27.4.3 Radial Deformation 446
27.4.4 D iscussion 446
27.5 Parametric Study 448
27.5.1 I nternal Pressure 449
27.5.2 L ay Angle 450
27.5.3 D /t Ratio 450
27.5.4 Amount of Kevlar Wires 451
27.6 Conclusions 452
References 453
28 Nonmetallic Bonded Flexible Pipe Under Combined
External Pressure and Bending 455
28.1 General 455
28.2 I ntroduction 455
28.3 Analytical Solution 457
28.3.1 Kinematics 457
28.3.2 Material Simplification 458
28.3.3 Constitutive Model 462
Contents xvii
28.3.4 Principle of Virtual Work 462
28.3.5 Amendment of Radius and Wall Thickness 463
28.3.6 Solution Method 463
28.4 Finite Element Model 464
28.5 Results and Discussions 465
28.5.1 Collapse of RTP Under External Pressure 465
28.5.2 Collapse of RTP Under Pure Bending 468
28.5.3 Collapse of RTP Under Combined Bending
and External Pressure 471
28.6 Conclusions 473
References 474
29 Fibre Glass Reinforced Flexible Pipes Under Internal Pressure 475
29.1 I ntroduction 475
29.2 Analytical Solution 476
29.2.1 Assumptions 476
29.2.2 Stress Analysis 476
29.2.3 Boundary Conditions 479
29.3 Finite Element Analysis 480
29.4 Results and Discussions 481
29.5 Winding Angle 483
29.6 Conclusions 484
References 485
30 Fibre Glass Reinforced Flexible Pipe Under External Pressure 487
30.1 I ntroduction 487
30.2 FE Analysis 488
30.2.1 I ntroduction 488
30.2.2 Geometrical Parameters and Material Properties 489
30.2.3 FE Modeling 490
30.3 Results and Discussions 491
30.3.1 I ntroduction 491
30.3.2 I nitial Imperfection 491
30.3.2.1 I nitial Ovality 491
30.3.2.2 I nitial Wall Eccentricity 492
30.3.3 Geometrical Configurations 494
30.3.3.1 D iameter Over Thickness Ratio D1/t1 of
Outer PE Layer 494
30.3.3.2 N umber of Reinforced Layers 495
30.3.3.3 D iameter Over Thickness Ratio D2/t2
of Inner Layer 496
30.3.4 Material 496
30.5 Conclusions 497
References 498
xviii Contents
31 Steel Wire Bonded Flexible Pipe Under Internal Pressure 499
31.1 I ntroduction 499
31.2 Analytical Solution 501
31.2.1 General 501
31.2.2 Stress and Strain Analysis 501
31.2.3 Simplification of Reinforced Layers 503
31.3 Finite Element Analysis 504
31.3.1 General 504
31.3.2 ABAQUS Modeling 504
31.4 Analysis Results 506
31.4.1 Comparison of Strains 506
31.4.2 E ffect of Winding Angle 507
31.5 E xperimental Test 508
31.5.1 General 508
31.5.2 Test Results 508
31.6 E ngineering Burst Pressure Formula 509
References 510
32 Steel Wire Bonded Flexible Pipe Under External Pressure 513
32.1 I ntroduction 513
32.2 Analytical solution 514
32.2.1 Fundamental Assumptions 514
32.2.2 N onlinear Ring Theory 514
32.2.3 Constitutive Relation of Material 516
32.2.4 Principle of Virtual Work Equation 518
32.3 N umerical Simulations 520
32.4 E xperimental Test 523
32.5 Conclusions 525
References 525
33 Steel Wire Bonded Flexible Pipe Under Bending and Internal Pressure 527
33.1 I ntroduction 527
33.2 Analytical Solution 528
33.2.1 Principle of Virtual Work 529
33.2.2 Burst Pressure of PSP in Axial Direction 531
33.2.3 Burst Pressure of PSP in Circumferential Direction 531
33.2.4 Constitutive Model for Materials 532
33.3 N umerical Simulations 535
33.4 Pure Bending Experimental Test 535
33.4.1 Test 535
33.4.2 Results and Discussion 537
33.5 Combined Internal Pressure and Bending Experimental Test 538
33.5.1 Test Facilities 539
33.5.2 Test Procedure 539
33.5.3 Test Results 540
33.6 Comparison of Results 540
33.7 Conclusions 541
References 542
Contents xix
34 Cross-Sectional Design and Case Study for Steel Wire
Bonded Flexible Pipe 543
34.1 I ntroduction 543
34.2 Cross-Sectional Design 544
34.2.1 D esign Procedure 544
34.2.2 D esign Parameters 544
34.2.3 Properties and Capacities 546
34.3 Case Study 550
34.4 V alidation by FE Model 551
34.5 Conclusions 555
References 555
35 Damage Assessment for Steel Wire Bonded Flexible Pipes 557
35.1 I ntroduction 557
35.2 Analytical Method 558
35.2.1 Basic Assumptions 558
35.2.2 Stress-Strain Relationship 558
35.3 Finite Element Analysis 564
35.4 Comparison between Analytical Method and FEM 565
35.4.1 E ffect of Steel Wire Winding Angle 567
35.4.2 E ffects of Steel Wire Diameter 568
35.4.3 E ffects of Missing Steel Wire 568
35.4.4 E ffect of Damaged Inner and Outer PE Layers 569
35.4.5 E ffects of Layer Interfacial Peeling 569
35.5 Summary 572
References 573
36 Third-Party Damage for Steel Wire Bonded Flexible Pipe 575
36.1 I ntroduction 575
36.2 Pipeline, Soil and Tamper Parameters 576
36.3 Finite Element Model 577
36.4 L oading and Boundary Conditions 578
36.5 Analysis Results 578
36.5.1 D ynamic Response 579
36.5.2 Tamping Velocity 581
36.5.3 Buried Depth 581
36.6 Summary 583
References 583 Index 585
Qiang Bai, PhD, has more than 20 years of experience in subsea and offshore engineering. He has taught at Kyushu University in Japan, UCLA in the USA, and he has worked at OPE, JP Kenny, and Technip. He is also the coauthor of three influential books on pipelines, which are standard in the industry.
Yong Bai, PhD, is the president of Offshore Pipelines & Risers Inc. in Houston, and is a professor and the director of the Offshore Engineering Research Center at Zhejiang University. He has previously taught at Stavanger University in Norway where he was a professor of offshore structures and has also worked with ABS as manager of the Offshore Technology Department as the JIP project manager and has also worked for Shell International E & P, JP Kenny, and MCS, where he was vice president of engineering. He is the co-author of two books on pipelines and over 100 papers on the design and installation of subsea pipelines and risers.
Weidong Ruan, PhD, is the author of numerous papers in the field of flexible pipelines and has co-authored chapters of books on pipelines and risers.
Yong Bai, PhD, is the president of Offshore Pipelines & Risers Inc. in Houston, and is a professor and the director of the Offshore Engineering Research Center at Zhejiang University. He has previously taught at Stavanger University in Norway where he was a professor of offshore structures and has also worked with ABS as manager of the Offshore Technology Department as the JIP project manager and has also worked for Shell International E & P, JP Kenny, and MCS, where he was vice president of engineering. He is the co-author of two books on pipelines and over 100 papers on the design and installation of subsea pipelines and risers.
Weidong Ruan, PhD, is the author of numerous papers in the field of flexible pipelines and has co-authored chapters of books on pipelines and risers.
