Page 426 - Pipelines and Risers
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Chapter 21
Design Codes and Criteria for Risers
21.1 Design Guidelines for Marine Riser Design
Different authorities and classification societies have developed riser design guidelines such
as NPD, HSE, NS, BS, CSA, ISO, API, DNV and ABS (see Chapter 22.8 for example).
In particular codes relevant for design are e.g.
APIRP16Q, 17A, 17B, 17C
Two design formats have been applied:
1. Working Stress Design (WSD)- API
2. Limit State Design (LSD)- DNV, IS0
The key issues in strength design are:
- Loads
- Resistance
- Acceptance Criteria
Where acceptance criteria are typically formulated as Sc<Rcly for the following failure
modes:
- Stress yielding
- Bursting (hoop)
- Global Buckling
- Local Buckling and Plastic Collapse
- Fracture
- Fatigue
